PAPC 333- 

United States Office of Air Quality EPA-45012-78-003b 

Environmental Protection Planning and Standards OAQPS NO. 1 2-091 

Agency Research Triangle Park NC 2771 1 March 1979 

Air 

GEPA Kraft Pulping 

Control of TRS 

Emissions from 

Existing Mills 

Guideline 

Series 

E PA-450/2-78-003b 

OAQPS NO. 1.2-091 

Kraft Pulping 

Control of TRS Emissions from 

Existing Mills 

Emission Standards and Engineering Division 

U.S. ENVIRONMENTAL PROTECTION AGENCY 

Office of Air, Noise, and Radiation 

Office of Air Quality Planning and Standards 

Research Triangle Park, North Carolina 2771 1 

March 1979 
OAQPS GUIDELINE SERIES 

The guidance series of reports is being issued by the Office of Air Quality 

Planning and Standards (OAQPS) to provide information to state and local 

air pollution control agencies; for example, to provide guidance on the 

acquisition and processing of air quality data and on the planning and 

analysis requisite for the maintenance of air quality. 

in this series will be available - as supplies permit - from the Library 

Services Office (MD-35), U.S. Environmental Protection Agency, Research 

Triangle Park, North Carolina 27711; or, for a nominal fee, from the National 

Technical Information Service, 5285 Port Royal Road, Springfield, Virginia 22161. 

Reports published 

Pub1 i cation No. EPA-450/2-78-003b 

(OAQPS NO. 1.2-091) 

ii 
Background Information and Final 

Environmental Impact Statement 

For Existing Kraft Pulp Mills 

Type of Actiop: Administrative 

Prepared by: 

-- -c 5-6 // 

(Date) . .- n-. .-- -A^.- 

Emission Staddards and Engineering Division 

U.S. Environmental Protection Agency 

Research Triangle Park, North Carolina 27711 

n Approved by: 

MAR 15 1979 

(Date 1 

Assistant Administrator for Air, 

Noise, and Radiation 

U.S. Environmental Protection Agency 

Washington, D.C. 20460 

Final Statement Submitted to EPA's Office of 

Federal Activities for Review on 

(Date) 

This document may be reviewed at: 

Central Docket Section 

Room 2903B, Waterside Mall 

401 M Street 

Washington, D.C. 20460 

Additional copies may be obtained at: 

U.S. Environmental Protection Agency Library (MD-35) 

Research Triangle Park, North Carolina 27711 

National Technical Information Service 

5285 Port Royal Road 

Springfield, Virginia 22161 

iii 
TABLE OF CONTENTS 

. 

Pa qe 

1 . Introduction 

1.1 Purpose of Document .................... 

1.2 TRS Compounds and Their Control .............. 

1.3 Standards of Performance for New Stationary Sources .... 

1.4 Emission Guidelines .................... 

Health and Welfare Effects of TRS Compounds 

2.1 Introduct’on ....................... 

2.2 Effects on Human Health .................. 

2.2.1 Odor Perception .................. 

2.3 Effects on Animals .................... 

2.4 Effects on Veqetation ................... 

2.5 We1 fare Effects of Atmospheric TRS ............ 

2.5.1 Effect on Property Values ............. 

2.5.2 Effects on Paint ................. 

2.5.3 Effects on Metals ................. 

2.6 Rationale ......................... 

2 . 

3 . Industry Characterization 

3.1 Geographic Distribution ................. 

3.2 Integration and Concentration ............... 

3.3 International Influence .................. 

4 . Process Descri pti on 

4.1 Kraft Pulping Process ................... 

. 4.2 Description of Individual Process Facilities ....... 

1-1 

1-4 

1-5 

1-6 

2-1 

2-3 

2-6 

2-8 

2-9 

2-9 

2-9 

2-10 

2-11 

2-11 

3-1 

3-1 

3-2 

4-1 

4-4 

iv 
Page 

5 . Emissions 

5.1 Nature of Emissions .................... 

5.2 Uncontrolled TRS Emissions ................ 

5.3 Typical TRS Emissions ................... 

6 . Control Techniques for TRS from Kraft Pulp Mills 

6.1 A1 ternative Control Techniques .............. 

6.1.1 Recovery Furnace .................. 

6.1.2 Digesters and Multiple Effect Evaporator Systems . . 

6.1.3 Lime Kiln ..................... 

6.1.4 Brown Stock Washer System ............. 

6.1.5 Black Liquor Oxidation System ........... 

6.1.6 Smelt Dissolving Tank ............... 

6.1.7 Condensate Stripper System ............. 

6.2 Summary of Retrofit Models ................ 

6.3 Installation and Start-up Time .............. 

7 . Emission Monitorinq and Compliance Testinq Techniaues and Costs 

7.1 Emission Measurement Techniques .............. 

7.1.1 Emission Monitorinq ................ 

7.1.2 Compliance Testinq ................. 

8 . Cost Analysis Of A1 ternative Emission Control Systems 

5-1 

5-3 

5-8 

6-1 

6-1 

6-9 

6-11 

6-13 

6-15 

6-17 

6-18 

6-19 

6-23 

7-1 

7-1 

7-2 

8.1 Introduction ....................... 8-1 

8.2 Methodology ....................... 8-3 

8.3 Costs of Affected Facilities ............... 8-6 

8.4 Incremental Costs for Model Mills ............. 8-21 

8.5 Aggregate Costs for Industry ............... 8-32 

8.6 Cost Effectiveness .................... 8-35 

V 
.. . 

. 

Paqe 

9 . Environmental Impact of TRS Controls 

9.1 Air Pollution Impact .................... 9-1 

9.1.1 Annual Air Emission Reductions ........... 9-1 

9.1.2 Annual Air Emission Increase ............ 9-3 

9.1.3 Atmospheric Dispersion of TRS Emissions ....... 9-5 

9.1.4 Changes in Solid and Liquid Wastes ......... 

9.1.5 Enerqy Consumption ................. 

10 . Emission Guidelines for Existing Kraft Pulp Mills 

10.1 General Rationale ..................... 

10.2 Evaluation of Individual Process Facilities ........ 

10.2.1 Recovery Furnace System .............. 

10.2.2 Digester System ................... 

10.2.3 Multiple Effect Evaporator System ......... 

10.2.4 Lime Kiln ..................... 

10.2.5 Brown Stock Washer System .............. 

10.2.6 Black Liquor Oxidation System ........... 

10.2.7 Condensate Stripper System ............ 

10.2.8 Smelt Dissolvinq Tank ............... 

10.2.9 Excess Emissions ................. 

10.3 Summary of the Rationale for Selectina the Best Control 

System .......................... 

10.4 Selection of the Format of the Emission Guidelines .... 

10.5 Monitoring Requirements .................. 

Appendix A . Summar.y of Kraft Mills in the United States 

Appendix B . Data Summary 

Appendix C . Dispersion Studies Results 

9-72 

9-12 

10-1 

10-3 

10-3 

10-7 

10- 

lo-! 0 

10-1 2 

10-13 

10-1 3 

10-14 

10-14 

10-17 

10-13 

10-20 

vi 
1. INTRODUCTION 

1.1 PURPOSE OF DOCUMENT 

This document has been prepared in accordance with regulations established 

under Section lll(d) of the Clean Air Act. 

EPA has established procedures whereby states submit plans to control existing 

sources of "designated pol 1 utants'l . Designated pol 1 utants are pol 1 utants 

whiih are not included on a list published under Section 108(a) (National 

Ambient Air Quality Standards) or 112(b)(l)(A) (Hazardous Air Pollutants), 

but to which a standard of performance forrew sources applies under Section 111. 

Under Section lll(d), emission standards are to be adopted by the states and 

submitted to EPA for approval. 

designated pollutants from existing facilities which, if new, would be 

subject to the standards of performance for new stationary sources. 

faci 1 i ties are called "designated facil i ties". 

Under the regulations, 

The standards will limit the emissions of 

Such 

In accordance with Section 111 of the Clean Air Act, standards of 

performance (NSPS) for eight source categories in the kraft pulp industry 

were promulgated on February 23, 1978. 

for total reduced sulfur (TRS) and particulates. 

pollutant. 

by which the states may develop emission standards for designated facilities. 

The standards include emission limits 

TRS is a designated 

This document is therefore being prepared to establish criteria 

1-1 
Subpart B of 40 CFR 60 contains the procedures under which states submit 

these plans to control existing sources of designated pollutants. 

requires the states to develop plans for the control of designated pollutants 

within Federal guidelines. As indicated in Subpart B, EPA will publish 

guide1 ines documents for development of state emission standards simultaneous 

Subpart B 

with promulgation of any new source standard of performance for a designated 

pollutant. These guidelines will apply to designated facilities which emit 

those designated pollutants and will include useful information for states, 

such as discussior, of the pollutant's effects, description of control 

techniques and their effectiveness, costs, and potential impacts. Finally, 

as guidance for the states, recommended emission limits (emission guidelines) 

and times for compliance are set forth and control equipment which will achieve 

these emission limits is identified. 

After publication of the final guideline document for the pollutant in 

question, the States will have nine months to develop and submit plans for 

control of that pollutant from designated facilities. Within four months 

after the date for submission of plans, the Administrator will approve or 

disapprove each plan (or portions thereof). 

is disapproved, the Administrator will promulgate a plan (or portion thereof) 

within six months after the date for plan submission. 

provisions of subpart B are basically patterned after Section 110 of the Act 

and 40 CFR Part 51 (concerning adoption and submittal of state implementation 

plans under Section 110). 

If a state plan (or portion thereof) 

These and related 

As discussed in the preamble to Subpart B, a distinction is drawn 

- between designated pollutants which may cause or contribute to endangerment 

of pub1 ic health (referred to as "health-related pollutants") and those for 

1-2 
which adverse effects on public health have not been demonstrated (referred 

to as "welfare-related pollutants"). For heal th-related pollutants, emission 

standards and compliance times in state plans must ordinarily be at least 

as stringent as the corresponding emission guidelines and compliance times 

in EPA's guideline documents. 

less stringent requirements for particular facilities or classes of facilities 

As provided in Subpart B, states may apply 

when economic factors or physical limitations make such application significantly 

more reasonable. Such justification may include unreasonable control costs 

resulting from plant age, location, process design, or the physical impossibility 

of installing the specified control system. 

time if sufficient justification is proven. 

unusual time del ays caused by unavai 1 abi 1 i ty of 1 abor , cl imatologi cal factors , 

scarcity of strategic materials, and large work backlogs for equipment vendors 

States may also relax compliance 

Such justification may include 

or construction contractors. 

For Welfare-related pollutants, states may balance the emission guidelines, times for compliance, and other information provided in a guideline 

document against other factors of public concern in establishing emission 

standards, compliance schedules, and variances provided that appropriate 

consideration is given to the information presented in the guideline document 

and c*t public hearing(s) required by Subpart B and that all other requirements 

of Subpart B are met. Where sources of pollutants that cause only adverse 

effects to crops are located in non-agricultural areas, for example, or 

where residents of a comunity depend on .an economically marginal plant 

for their livelihood, such factors may be taken into account (in addition to 

those that would justify variances if a heal th-related pollutant was involved). 

Thus, states will have substantial fqexibility to consider factors other than 

technology and costs in establishing plans for the control of welfare-related 

pollutants if they wish. 

1-3 

P 
For reasons discussed in Chapter 2 of this document, the Administrator 

has determined that TRS emissions from kraft pulp mills may cause or 

contribute to endangerment of the public welfare but that adverse effects on 

public health have not been demonstrated. As discussed above, this means 

that TRS emissions will be considered a welfare-related pollutant and the 

states will have greater flexibility in establishing plans for the control 

of TRS thanwould be the case if public health might be affected. 

This state guidelines document briefly discusses the effects of reduced 

sulfur compounds on health, and on crops, materials, and animals. 

process categories having reduced sulfur emissions are discussed. 

greatest emphasis, however, has been placed on the technical and economic 

evaluation of control techniques that are effective in reducing total reduced 

sulfur emissions, with particular emphasis on retrofitting existing mills. 

Section 6.2 proposes several control systems available to the states. The 

costs of these control systems is analyzed in Chapter 8, while Chapter 9 

assesses the environmental and energy impact of these control systems. Finally, 

as guidance for the states, recommended emission limitations are set forth 

and control equipment which will achieve these emission 1 imitations is suggested. 

1.2 TOTAL REDUCED SULFUR COMPOUNDS AND THEIR CONTROL 

Eight 

The 

For purposes of new sorces performance standards (NSPS) and the attendant 

requirements of Section lll(d), "total reduced sulfur'' (TRS) is the designated 

pollutant to be controlled. 

compounds consisting primarily of hydrogen sulfide, methyl mercaptan, dimethyl 

sulfide, and dimethyl disulfide. Control of TRS emissions at kraft pulp mills 

is well demonstrated by proper operation of the combustion sources or incineraTRS in this document refers to a combination of 

tion of the exhaust gases. 

1-4 
The limited information currently available on the health and welfare 

effects of TRS generally deals with hydrogen sulfide (HzS). 

effects are noticeable down to 20 ppmv, but this concentration is much 

higher than expected in the ambient air as a result of even uncontrolled 

TRS emissions from kraft pulp mills. HzS at concentratiomdown to a few 

parts per billion is recognized as an odor nuisance. 

Adverse health 

The OSHA occupational 

exposure maximum for'H25 is 29 ppmv, not to be.exceeded at any time. 

1.3 STANDARDS OF PERFORMANCE FOR NE14 STATIONARY SOURCES 

In accordance with Section 111 of the Clean Air Act, standards of 

performance for eight affected facilities or emission sources in the kraft 

pulping industry have been promulgated (Subpart RB of 40 CFR Part 60). These 

sources are the recovery furnace (both straight kraft and cross-recovery 

furnaces)*, digester system, mu1 tiple-effect evaporator system, li,me kiln, 

brown stock washer system, black 1 iquor oxidation system, smelt dissolvincl 

tank, and condensate stripper system. Information and emission data collected 

during development of the proposed new source performance standards indicate 

that best demonstrated control technology can limit the TRS emissi\ons to five 

parts per million by volume dry gas basis for all new sources except lime 

kilns and cross-recovery furnaces, which can be limited to 8 ~pm and 25 ppm, 

respectively. 

Water treatment ponds, however, are not covered by the proposed NSPS 

because data on actual TRS emissions are not available and accurate sampling 

methods for determining TRS and other odorous emissions from treatment ponds 

are not sufficiently developed or demonstrated. Therefore, water treatment 

ponds will not be covered in this document. 

-7 

*NOTE: 

straight kraft recovery furnaces and cross-recovery furnaces, unless otherwise 

specified. 

Throughout the document, the term "recovery furnaces'' will imply both 

1-5 
1.4 EMISSION GUIDELINES 

1.4.1 Recodended TRS Emission Limitations for the States 

Emission guidelines for control of TRS emissions that may be achieved 

by application of best adequately demonstrated technology to existing facilities 

are listed in Table 1-1. These emission guidelines are less stringent in 

some cases than the standards proposed for new sources since the application 

of the best adequately demonstrated technology for new sources could result 

in excessive control costs at existing sources. However, emission guidelines 

do require the sawe type of control as judged to be best adequately demonstrated 

technology for new sources for the three major TRS sources (recovery furnace, 

digester system, and mu1 tiple-effect evaporator system). The justification 

for these emission guidelines are discussed more completely in Chapters 8 and 9. 

Adoption of these guidelines would result in an overall nationwide TRS 

emission reduction of about 82 percent. 

1-6 
Table 1-1. TRS EMISSION GUIDELINES FOR EXISTING 

KRAFT PULP MILLS 

Emission Guidelines 1 

Affected Fact 1 i ty 

Recovery Furnace 2 

01 d Design Furnaces3 20 PPm 

New Design Furnaces4 5 PPm 

Cross Recovery Furnaces 25 PPm 

Di ges ter Sys tern 

Mu1 tiple-Effect Evaporator System 

5 PPm 

5 PPm 

Lime Kiln 20% ppm5 

Brown Stock Washer System No Control 

Black Liquor Oxidation System No Control 

Condensate Stripper System 5 PPm 

Smelt Dissolving Tank 0.0084 g/kg BLS 

'Guidelines given are in terms of twelve-hour averages, e.g., from 

fw'discrete contiguous twelve-hour periods of time, 

20ne percent of all twelve-hour TRS averages per quarter year above 

midnight to noon. These are not "running" averages, but are instead 

Lhe specified level, under conditions of proper operation and 

maintenance, in the absence of start-ups, shutdowns and malfunctions, 

are not considered to be excess\emissions. 

3Furaaces not constructed with air pollution control as an 

objective (see definitions on pages 6-7 and 10-3). 

4Furnaces designed for low TRS emissions and having stated in 

their contracts that they were constructed with air Pollution 

control as an objective (see definitions on pages 6-7 and 10-3)- 

5Tw0 Dercent of all twelve-hour TRS averages per quarter year above 

20 ppm, under conditions of proper operation and maintenance, in the 

absence of start-ups, shutdowns and malfunctions, are not considered 

to be excess emissions. 

~ 

1-7 

2. HEALTH AND WELFARE EFFECTS OF 

TOTAL REDUCED SULFUR COMPOUNDS 

2.1 INTRODUCTION 

In accordance with 40 CFR 60.22(b), promulgated on November 17, 

1975 (40 FR 53340), this chapter presents a summary of the available 

information on the potential health and welfare effects of total 

reduced sulfur (TRS) compounds and the rationale for the Administrator's 

determination that TRS is a welfare-related pollut7nt for purposes of 

section lll(d) of the Clean Air Act. 

The Administrator first considers potential health and welfare effects 

of a designated pollutant in connection with the establishment of 

standards of performance for new sources of that pollutant under 

section lll(b) of the Act. 

Administrator must find that the pollutant in question "may contribute 

significantly to air pollution which causes or contributes to the 

endangerment of public health or welfare" [see section 111 (b)(l)(a)]. 

Because this finding is, in effect, a prerequisite to the same pollutant 

being identified as a designated pollutant under section lll(d), all 

designated pollutants will have been found to have potential adverse 

effects on public health, public welfare, or both. 

Before such standards may be established, the 

2- 1 
As discussed in section 1.1 of this document, Subpart B of Part 60 

distinguishes between designated pollutants that may cause or contribute 

to endangerment of pub1 ic health (referred to as "heal th-related pollutants") 

and those for which adverse effects on public health have not been 

demonstrated ("welfare-related pollutants"). 

of the distinction is that states have more flexibility in establishing 

plans for the control of welfare-related pollutants than is provided for 

plans involving heal th-related pollutants. 

In general , the significance 

In determining whether a designated pollutant is health-related or 

welfare-related for purposes of section 111 (d) , the Administrator 

'considers such factors as: 

pollutant on public health and welfare; (2) potential ambient concentrations 

of the pollutant; (3) generation of any secondary pollutants for which 

the designated pollutant may be a precursor; (4) any synergistic effect 

with other pollutants; and (5) potential effects from accumulation in 

the environment (e.g., soil, water, and food chains). 

(1) known and suspected effects of the 

It should be noted that the Administrator's determination of whether 

a designated pollutant is heal th-related or welfare-related for purposes 

of section lll(d) does not affect the degree of control represented by 

EPA's emission guidelines. 

Subpart B, EPA's emission guidelines [like standards of performance for 

new sources under section 111 (b)] are based on the degree of control 

achievable with the best adequately demonstrated control systems (considering 

costs), rather than on direct protection of public health or welfare. 

For reasons discussed in the preamble to 

This 

2- 2 
is true whether a particular designated pollutant has been found to be 

health-related or welfare-related. 

that finding is the degree of flexibility that will be available to the 

states in establishing plans for control of the pollutant, as indicated 

above. 

Thus, the only consequence of 

Very little information is available on the effects of the total 

reduced sulfur compounds discharged from kraft pulp mi 11 s on human heal th , 

animals, vegetation, and materials. Almost all the information that was 

found during this investigation deals with only hydrogen sulfide (H2S). 

Essentially no information on the health and welfare effects of the other 

reduced sulfur compounds (methyl mercaptan, dimethyl sulfide, and dimethyl 

disulfide) emitted from kraft pulp mills was found. Therefore, this 

chap er discusses the effects of hydrogen sulfide on y. 

sulf de is the predominant TRS compound emitted by kraft pulp mills. 

2.2 

However, hydrogen 

EFFECTS OF ATMOSPHERIC TRS ON HUMAN HEALTH’ 

At sufficiently high concentrations, hydrogen sulfide is very toxic 

to humans. It generally enters the human body through the respiratory 

tract, from which it is carried by the blood stream to various body organs. 

Hydrogen sulfide that enters the blood can lead to blocking of oxygen 

transfer, especially at high concentrations. 

sulfide acts as a cell and enzyme poison and can cause irreversible changes 

in nerve tissue. 

In general, the hydrogen 

Some of the effects of hydrogen sulfide and the air concentrations at 

which they occur are shown in Table 2-1. At high concentrations 
Table 2-1 

EFFECTS OF HYDROGEN SULFIDE INHALATION ON HUMANS 

Hydrogen Sulfide 

Concentration, pg/m (ppm) Effects 

1-45 (7.2 x - 3.2 x lo-’) Odor threshold. No reported injury 

to health 

IO (7.2 Threshold of reflex effect on eye 

sensitivity to light 

150 (0.10) Smell slightly perceptible 

500 (0.40) 

15,000 (10.0) 

30,000 (20.0) 

30,000-60,000 (20.0-40.0) 

75D,OOO (1 10) 

270,000-480,000 (200-350) 

640,000-1,120,000 (460-810) 

900,000 (650) 

1,160,000-1,370,000 (840-990) 

1,500,000+ (1 1 OO+) 

Smell definitely perceptible 

Minimum concentration causing eye 

irritation 

Maximum a1 lowable occupational 

exposure for 8 hours (ACGIH 

To1 erance Limit ) 

Strongly perceptible but not intolerable smell. Minimum concentration causing lung irritation 

Olfactory fatigue in 2-15 minutes; 

i r r i t a t i on of eyes and respiratory tract after 1 hour; death in 

8 to 48 hrs 

No serious damage for 1 hour but 

intense local irritation; eye 

irritation in 6 to 8 minutes 

Dangerous concentration after 30 

minutes or less 

Fatal in 30 minutes 

Rapid unconsciousness, respiration 

arrest, and death, possibly 

without odor sensation 

Immediate unconsciousness and rapid 

death 

2- 4 
3 (over 1,000,000 pg/m ), hydrogen sulfide can cause death quickly by 

paralysis of the respiratory center. 

quickly to uncontaminated air and respiration is initiated before heart 

action stops, rapid recovery can be expected. 

(30,000 to 500,000 pg/m ), hydrogen sulfide causes conjunctivitis, lachrymal 

secretion , respiratory tract irritation , pulmonary edema, damage to the 

heart muscle, psychic changes , disturbed equi 1 i brium, nerve paralysis , 

spasms, unconsciousness, and circulatory collapse. Some common symptoms 

are metallic taste, fatigue, diarrhea, blurred vision, intense aching of 

the eyes, insomnia, and vertigo. 

However, if the victim is moved 

At lower concentrations 

3 

The Occupational Safety and Health Administration (OSHA) has established 

a maximum allowable exposure concentration (not to be exceeded at any time) 

3 for hydrogen sulfide of 30,000 pg/m In comparison, OSHA has 

set a maximum allowable exposure concentration for methyl mercaptans of 

(20 ppm). 

only 15,000 ug/m’ (10 ppm). 

Concentrations 

to be realized near 

of ambient hydrogen 

period in 1961 and 

3 of TRS as high as 30,003 pg/m 

existing kraft pulp mills. 

sulfide concentration were made during a six-month 

962 in the Lewiston, Idaho, area where the major 

(20 ppm) ar? not likely 

For example, measurements 

contributor of gaseous pollutants was a pulp mill which had only the recovery 

furnace controlled for TRS emissions. The levels of hydrogen sulfide were 

pollution episode in November 

were measured. These levels 

onal exposure concentration 

3 generally less than 15 pg/m . During an air 

1961 , peak 2-hour concentrations of 77 pg/m’ 

are well below the maximum allowable occupat 

es tab 1 i s hed by OSHA. 

2- 5 
For the purpose of evaluating the air pol 1 ution impacts associated 

with alternative emission limits (see Chapter 9), dispersion studies were 

performed by EPA on model kraft pulp mills. 

that the maximum ground-level ambient concentration of hydrogen sulfide 

resulting from an uncontrolled 1 arge sized (907 megagrams/day) kraft pulp 

mill would be about 10,300 pg/m (one-hour average). 

though much higher than actually measured at the existing mill mentioned 

above, is still lower than the minimum exposure concentration that causes 

eye irritation. 

These studies indicated 

3 This level, even 

2.2.1 Odor Perception 

The odor characteristic of kraft mills is principally due to the 

presence of a mixture of hydrogen sulfide, methyl mercaptan, dimethyl 

sulfide, and dimethyl disulfide. 

and are detectable at concentrations as low as 1 part per billion (ppb). 

However, the odor perception thresholds of these gases vary considerably 

These sulfides are extremely odorous 

among individuals and apparently depend on the age and sex of the 

individuals, the size of the town where they live, and whether they 

smoke. 

1 and 45 pg/m 

concentration increases. 

The reported odor t hres hol d of hydrogen sul fide varies between 

3 (see Table 2-2). The odor becomes more intense as the 

At very high concentrations (H2S above 320,000 

pg/m’), the smell is not as pungent, probably due to paralysis of the 

olfactory nerves. 

there is little sensation of odor and death can occur rapidly. 

this dulling of the sense of smell constitutes a major danger to persons 

3 

Therefore, 

At hydrogen sulfide concentrations over 1,120,000 pg/m , 

-potentially exposed to high concentrations of hydrogen sulfide. The 

reported odor thresholds for mettiyl mercaptan, dimethyl sulfide, and 

dimethyl disulfide are shown in Table 2-3. 

2-6 
Table 2-2 

ODOR DETECTION THRESHOLD FOR HYDROGEN SULFIDE 

(PPmv) 3 i yg/m 

PPm 

9-45 

7.1a 

.71 b 

15 

6.8‘ 

12-30 

1nm3 

(.007-.032) 

(. 005) 

(.0005) 

(.017) 

t.005) 

( . oog-. 022) 

0.0021 

0.0010 

0.0056 

Hydrogen sulfide from sodium sulfide. a 

bHydrogen sul fide gas. 

‘Mean value ratio of highest to lowest odor 

threshold concentration detected by all 

observers in successive tests is 3.18. 

4.5 

2.9 

23.7 

Table 2-3. ODOR THRESHOLDS OF REDUCED SULGUR 

9 

COMPOUNDS OTHER THAN HYDROGEN SULFIDE 9 

Compound 

Methyl Mercaptan-CH3SH 

Dimethyl Sul fide- ( CH3)2S 

Di me thy1 Di su 1 f i de- (CH3 2S2 

1 I 

2- 7 
At the ambient ground-level concentrations likely to occur near an 

uncontrolled kraft pulp mill, as determined by EPA dispersion estimates, 

odors would definitely be perceptible. 

typical controls (see Chapter 5) would likely have an odor level that is 

sl ightly perceptible. 

A kraft pulp mill that operates 

Most studies dealing with health effects of kraft pulp mill odors are 

inconclusive. 

kraft pulp mill are annoyed by the odor, and that short-term effects 

(vomiting, headaches, shortness of breath, dizziness) occur in some 

individuals after prolonged exposure. 

The studies show that populations in the area of an uncontrolled 

These effects have been reported to 

be of a psychosomatic nat~re;~ however, the evidence in this reaard is not 

conclusive.6 Studies indicate that the sense of smell becomes rapidly 

fatigued in the presence of H2S at levels above the odor th~eshold.~ This 

olfactory fatigue prevents the odor from beina perceived over the lona 

term. &en perception of the odor becomes weaker or disappears, the effects 

of the odor also cease. 

8 

2.3 EFFECTS OF ATMOSPHERIC TRS ON ANIMALS’ 

Hydrogen sulfide produces about the same health effects in domestic 

animals as in man, at approximately the same air concentrations. 

Air Pollution Control Association Committee on Ambient Air Standards stated 

that spontaneous injury to animals occurs at 150,000 to 450,009 ug/m of 

The 

3 

hydrogen sulfide, These concentrations are, however, much higher than are 

expected to result from existing kraft pulp mill operation. 

2 -8 
2.4 EFFECTS OF ATMOSPHERIC TRS ON VEGETATION” 

There is little evidence that hydroqen sulfide causes sianificant 

injury to field crops at environmental air conditions. 

Experiments have indicated that little or no injury occurred to 29 

3 species of plants when they were fumigated with less than 60,000 pq/m of 

hydrogen sulfide for five hours. After five hours at 600,000 pq/m3, some 

species were injured, but not all. 

and coleus showed appreciable injury at concentrations of 600,000 pa/m . 

At concentrations between 60,000 and 600,000 pq/m , qladiolus, rose, 

Boston Fern, apple, cherry, peach 

3 

3 

castor bean, sunflower, and buckwheat showed moderate in-jurv. Tobacco, 

cucumber, salvia, and tomato were sliahtly more sensitive. 

In general, hydrogen sulfide injures the vounaest plant leaves rather 

than the middle-aged or older ones. Youna, rapidlv elonaatina tissues are 

the most severely injured. Typical exterior s.ymptoms are wiltina without 

typical discoloration (which starts at the tip of the leaf). The scorchina 

of t.he younqest leaves of the plant occurs first. 

2.5 WELFARE EFFECTS OF ATMOSPHERIC TRS 

2.5.1 Effect on Property Values 11,12 

Sociologically, such noxious odors can ruin personal and community pride, 

i n t e r f e r e w i t h human relations in various ways, discourage capital improvements, 

lower socioeconomic status, and damage a community’s reputation. Economically, 

they can stifle, growth and development of a community. 

labor prefer to locate in a desirable area in which to live, work, and play; 

Both industrv and 

and the natural tendency is to avoid communities with obvious odor Droblems. 

Tourists also shun such areas. 

revenues, payrolls, and sales can be disastrous to a community. 

The resultina decline in property values, tax 

2 -9 
In summary, the presence of odors may reduce the value of property 

within the affected area, dependinq upon the extent to which the odors are 

considered objectionable to the buyer and seller of the property. 

2.5.2 Effects on Paint 13 

Hydrogen sulfide in the atmosphere reacts with paint containina heavy 

metal salts in the pigment and the drier to form a precipitate which darkens 

or discolors the surface. Lead, mercury, cobalt, iron, and tin salts cause 

a gray or black dfscoloration; cadmium salts cause a yellowish-oranae 

discoloration. Damage to house paint caused by hydrogen sulfide emissions 

from a kraft pulp mill has been reported in the communities of Lewiston, 

Idaho, and Clarkston, Washington. 14 

Lead is probably the most common metal to exhibit discoloration 

caused by the formation of black lead sulfides. The most comnonlv used 

white piqment in the past was basic lead carbonate. 

pigments have now aenerally replaced the use of lead carbonate in the paint 

industry. 

coatings because of the added durability they impart to paint films. 

Titanium dioxide 

However, lead pigments continue to be used in the area of road 

Experiments have shown that old lead-base paints are more susceptible 

to hydrogen sulfide damage than are new ones. These experiments have also 

shown that darkening is dependent on duration of exposure and concentration, 

and can occur after exposure to hydrogen sulfide concentrations as low as 

75 pg/m for two hours. 

by hydrogen sulfide depends on: 

perature and moisture; (3) hydrogen sulfide concentration; (4) aae and 

condition of paint; and (5) presence of other contaminants in the air. 

3 These experiments indicate that paint darkenina 

(1) heavy metal content of paint; (2) tem2-1 0 
15 2.5.3 Effects on Metals 

Copper and silver can tarnish rapidly in the presence of hydroqen 

sulfide. 

time resists attack by hydrogen sulfide. Experiments have indicated that 

hydrogen sulfide-sensitive metals, such as silver and copper, will tarnish 

when exposed to hydrogen sulfide concentrations above 4 pq/m for 40 hours 

However, copper that has been exposed to unpolluted air for some 

3 

at room temperature. 

to occur. 

Both moisture and oxygen must be present for tarnishing 

The sulfide coating formed on copper and silver electrical 

contacts can increase resistance when the contacts are closed. In some 

cases, this can result in the contacts becomina welded shut. 

Some alloys of gold, even such a hiah-carat alloy as 69 percent aold, 

25 percent silver and 6 percent platinum, will tarnish when exposed to 

hydrogen sulfide. However, aold (14-carat and above) and aold leaf 

(95 percent gold and above) usually will not tarnish appreciably from 

exposure to atmospheric hydroqen sul fide. 

Hydrogen sulfide will attack zinc at room temperature. A zinc sulfide 

film is formed which prevents further corrosion. At hiqh temperatures, the 

attack is quite vigorous. 

and at ambient temperatures, hydrogen sulfide is not corrosive to ferrous 

metals. 

At concentrations normally found in the atmosphere 

2.6 RATIONALE 

Based upon the information provided in the precedinq sections of Chapter 2, 

is it clear that TRS emissions from kraft pulp mills have no sianificant 

effect on human health. TRS emissions, however, are hiqhly odorous and 

studies show that the population in the area of an existina kraft pulp mill 

2-1 1 
is annoyed by the odor. Hydrogen sulfide also has effects on paints and 

metals at concentrations that can occur in the vicinity of existina kraft 

pulp mills. 

pulp mills do not contribute to the endangerment of public health. Thus, 

TRS emissions wi 11 be considered a we1 fare-re1 ated pol 1 utant for purposes 

of Section 111 (d) and Subpart B of Part 60. 

The Administrator has concluded that TRS emissions from kraft 

2-1 2 
REFERENCES FOR CHAPTER 2 

1. I Preliminary Air Pollution Survey of Hydrogen Sulfide, A Literature 

Review. U. S. Department of Health, Education, and Welfare. October 1969. 

pp 2-4; 29-32. 

2. Op City Reference 1. Table 1. 

3. Adams, D. F., and F. A. Young. Kraft Odor Detection and Objectionability 

Thresholds. Washington State University Progress Report on U. S. Public 

Health Service Grant. 1965. 

4. Leonardos, G., et al. Odor Threshold Determinations of 53 Odorant 

Chemicals. 

Association. St. Paul , Minnesota. June 1968. 

Presented at 61st Annual Meeting of the Air Pollution Control 

5. Pavanello, R., and D. Rondia. “Odor Nuisance and Public Health, Part 2”. 

Water Waste Treatment. June 1971. 

6. 

I1 1 inois Institute for Environmental Quality. PB-233-843. March 1974. 

Hydrogen Sul fide Heal th Effects and Recommended Air Qual i ty Standard. 

7. Sullivan, R. J. Preliminary Air Pollution Survey of Odorous Compounds. 

Department of Health, Education, and Welfare. Raleigh, North Carolina. 

APTD 69-42. October 1969. pp 8-9. 

8. Op Cit, Reference 6. pp 17-22. 

9. Op Cit, Reference 1. pp 6-7. 

10. Op City Reference 1. p 12. 

11. Op Cit, Reference 7. pp 1-2. 

12. A Study of the Social and Economic Impact of Odors. Copley International 

Corporation. EPA Contract No. 68-02-0095. February 1973. 

2-1 3 
I 

z 

I 

13. Op Ci t, Reference 1. pp 16-19. 

14. “A Study of Air Pollution in the Interstate Region of Lewiston, Idaho, 

and Clarkston, Washington”. Pub1 ic Health Service Publication 999-AP-8. 

1964. 

15. Op Cit, Reference 1. pp 19-20. 

2-1 4 
3. INDUSTRY CHARACTERIZATION 

3.1 Geographic Distribution 

As of December 1975, there were 56 firms operating about 120 

kraft pulping mills in 28 states. 

and mill capacity is found in the South. Alabama, Georgia, and 

Louisiana are the leaders. Alabama has 13 mills and 10 percent 

of U.S. mill capacity. Georgia has 11 mills and 13 percent of U.S. 

mill capacity. And Louisiana has 11 mills and 11 percent of U.S. 

capacity. 

industry has occurred mainly in the South.' 

modific'ations to existing mills as well as plans for new mills are found in 

all sections of the country. 

Most U.S. kraft pulping mills 

Over the past 20 years, growth in the kraft pulping 

However, recent and planned 

2 

3.2 Integration and Concentration 

Only about 1/3 of the 56 firms are producers of pulp, paper, 

and/or paperboard exclusively. 

variety of activities. The activities include chemical manufacture, 

detergent production, magazine publishing, land development, and can 

production. 

The others are engaged in a wide 

The degree of dependency on kraft pulping and related 

activities varies anong these horizontally integrated firms. 

International Paper Company derived 55.6 percent of their 1974 

sales from pulp, paper, and paperboard production,Ethyl Corporation 

derived 11 percent of 1974 sales from pulp and paper operations. 

Whereas 

Besides being horizontally integrated, the U.S. kraft pulping 

industry is highly concentrated. The 6 largest firms in terms of mill 

Capacity account for 40 percent of U.S. kraft pulp capacity. 

10 largest account for 56 percent of U.S. kraft pulp capacity. 

The 

3-1 
Vertical integration is another characteristic of the U.S. kraft 

pulping industry. Only 41 U.S. kraft pulping mills are listed in the 

directory of world market pulp producers. 

grade listed is bleached 

wood. 

The most prevalent kraft 

hardwood followed closely by bleached softMoreover, appearance in the directory does not mean the mills' 

pulp cannot be used captively. 

produced at the designated mills. However, nearly all kraft pulp 

(about I30 percent) produced in the U.S. is not marketed but is used 

~aptively.~ In fact, 109 kraft pulping mills also have facilities at 

When available, pulp for market is 

the same location for producing paper and paperboard. 

mills cannot always satisfy the kraft pulping requirements of the 

paper and paperboard facilities. 

from other U.S. and Canadian mills are required to fill the kraft 

pulping voids. 

3.3 International Inf 1 uence 

However, these 

Oftentimes, intracompany transfers 

The U.S. kraft pulping industry is not devoid of foreign influence. 

Pulp, paper, and paperboard production in other countries, especially 

Canada, has a pronounced influence on U.S. kraft pulping firms and 

trade balances. 

kraft pulp and the fourth leading exporter (behind Canada, Sweden, 

and Finland), the U.S. has been a net importer of kraft pulp. 

90 percent of the kraft pulp imported to the U.S. comes from Canada. 

This is not surprising in view of the earlier statement about intracompany transfers and the fact that a third of the U.S. kraft pulp 

producers have kraft pulping facilities in Canada. 

Although the U.S. is the world's largest producer of 

Over 

- 

The aforementioned industry characterization statements were 

derived primarily from Appendix A and Tables 3-1 and 3-2. Appendix A displays 

3-2 
Table 3-1. SUMMARY INDUSTRY STATISTICS: FIRMS-MILL NUMBER AND CAPACITY 

DISTRIBUTION 

Capacity 

U.S. Mills 

Megagram Tons % of U.S. 

- Firm # U.S. Mills % U.S. Total Per Day Per Day Total 

Allied Paper, Inc. 

(sub. of SCM) 

A1 ton Box Board Co. 

American Can Co. 

Appl eton Papers , Inc. 

(Div. of NCR) 

Boise Cascade Corp. 

Bowa ter , Inc. 

1 1 445 (490) <1 

1 1 590 (650) <1 

2 2 1,125 (1,240) 1 

1 1 163 (180) negligible 

5 4 3,438 (3,790) 4 

2 2 1,360 (1,500) 1 

Brown Co. 1 1 635 (700) <1 

Champion-International 3 3 2,430 (2,680) 3 

Chesapeake Corp. of Va. 1 1 1,043 (1,150) 1 

Container Corp. of Amer. 2 2 2,040 (2,250) 2 

Continental Can Co. 4 3 3,355 (3,700) 4 

Crown Zel 1 erbach 5.5 5 3,824 (4,216) 4 

Consolidated Papers, Inc. 1 1 358 (395) neglibible 

(sub. of Marcor) 

Diamond Int'l Corp. 1 1 385 (425) negligible 

Federal Paper Board 

Co., Inc. 

1 1 1,088 (1,200) 1 

Fibreboard Corp. 1 1 408 (450) negligible 

Georgia-Pacific Corp. 4 3 5,007 (5,520) 5 

Gilman Paper Co. 1 1 998 (1,100) 1 

Great Northern Nekoosa 3 3 2,276 (2,510) 2 

Green Bay Packaging, Inc. 1 1 590 (6501 <1 

Gulf States Paper Corp. 2 2 794 (875) <1 

Hammermill Paper Co. 2 2 777 (856) <1 

Hoerner Mal dorf Corp. 2 2 1,950 (2,150) 2 

P.H. Glatfelter Co. 1 1 454 (500) negligible 

Corp. 

Hudson Paper Co. 

ITT Rayonier, Inc. 

1 861 (950) <1 

1 1,133 (1,250) 1 

Inland Container Corp. 1.5 1 1,100 (1,213) 1 

3-3 
Table 3-1 (Continued). SUMMARY INDUSTRY STATISTICS: FIRMS-MILL NUMBER AND 

CAPACITY DISTRIBUTION 

Capacity 

U.S. Mills 

Megaqram Tons % of U.S. 

- Firm # U.S. Mills % U.S. Total Per Day Per Day Total 

International Paper Co. 

Interstate Container Corp. 

Kemberly-Clark Corp. 

Lincoln Pulp & Paper Co. 

(Div. of Premoid) 

Longview Fibre Co. 

Louisiana Pacific Corp. 

MacMi 11 an B1 oedel Ltd. 

Mead Corp. 

Mosinee Paper Corp. 

Olin Kraft, Inc. 

Owens-Ill inois, Inc. 

Oxford Paper 

(Div. Ethyl Corp.) 

Packaging Corp. of 

Amer. (A Tenneco Co.) 

Penntech Papers, Inc. 

Pineville Kraft Corp. 

Potlatch Corp. 

Procter & Gamble Co. 

St. Joe Paper Co. 

St. Regis Paper Co. 

Scott Paper Co. 

Simpson Lee Paper Co. 

Southland Paper Mills, Inc. 

Southwest Forest Industries 

South Carolina Industries 

(79% owned by Stone Container Corp. ) 

(sub. of Time, Inc.) 

Temple-Eastex, Inc. 

Union Camp Corp. 

Western Kraft 

Westvaco Corp. 

Weyerhauser Co. 

Totals 56 

14 

1 

1 

1 

1 

1 

1 

4 

1 

1 

2 

1 

1 

1 

1 

2 

1 

1 

4 

3.5 

1.5 

2 

1 

1 

1 

3 

3 

4 

7 

119 

- 

12 

1 

1 

1 

1 

1 

1 

3 

1 

1 

2 

1 

1 

1 

1 

2 

1 

1 

3 

3 

1 

2 

1 

1 

1 

3 

3 

3 

6 

3-4 

14,500 

500 

530 

2 90 

1,723 

635 

840 

2,837 

160 

1,043 

1,610 

530 

703 

163 

800 

1,225 

81 6 

1,180 

4,880 

2,450 

690 

81 6 

545 

61 2 

1,180 

4,517 

1,243 

3,858 

5,620 

95,750 

(15,985) 14 

(550) <1 

(585) <1 

(320) <1 

(775) <1 

negligible 

<1 

1 

<1 

1 

5 

3 

<1 

<1 

<1 

<1 

(1,300) 1 

( 4 , 980 1 

(1,370) 1 

(4,254) 5 

5 

(6,195) - 6 

(105,567) 
Table 3-2. SUMMARY INDUSTRY STATISTICS: STATES-MILL NUMBER AND CAPACITY 

DISTRIBUTION 

State 

A1 abama 

Arizona 

Arkansas 

California 

Florida 

Georgia 

Idaho 

Kentucky 

Louisiana 

Maine 

Mary1 and 

Michigan 

Minnesota 

Mississippi 

Montana 

New Hamps hi re 

New York 

North Carol ina 

Ohio 

0 kl a homa 

Oregon 

Pennsyl van i a 

South Carolina 

Tennessee 

Texas 

Virginia 

Washington 

Wisconsin 

Totals 28 

Number of 

Mills 

13 

1 

6 

4 

8 

11 

1 

2 

11 

6 

1 

2 

2 

4 

1 

1 

1 

5 

1 

1 

7 

3 

4 

2 

% of U.S. 

Total 

11 

1 

5 

3 

7 

9 

1 

2 

9 

5 

1 

2 

2 

3 

1 

1 

1 

4 

1 

1 

6 

3 

3 

2 

6 5 

4 3 

7 6 

- 

4 3 

- 

119 

State Mill 

Capacity 

Megagram Tons % of U.S. 

Per Day Per Day Total 

9,325 

545 

4,925 

1,732 

8 , 400 

12,250 

860 

835 

10,570 

3 , 583 

603 

7 50 

785 

4,270 

1,090 

635 

535 

5,125 

490 

1,450 

5,357 

780 

4 , 983 

1,156 

4,145 

4,127 

5,310 

1,140 

- 

95 , 750 (1 05,567) 

3-5 
kraft mill characteristics. Table 3-1 exhibits mill number and 

capacity distribution by firm. Table 3-2 exhibits mill number and 

capacity distribution by state. 

3-6 
k 

REFERENCES FOR CHAPTER 3 

1. Guthrie, John A. An Economic Analysis of the Pulp and Paper Industry. 

I Pullman, Washington, Washington State University Press, 1972, pp. 1-15. 

2. Van Derveer, Paul D. Profiles of the North American Pulp and Paper 

Industry, Pulp & Paper. June 30, 1975. pp. 32-33; 36-38; 43-44; 

48-49. 

3. Wood Pulp Statistics 36th Edition. 

American Paper Institute, Inc., October 1972. pp. 63-83. 

Pulp & Raw Materials Group, New York, 

3-7 

4. PROCESS DESCRIPTION 

Manufacturing of paper and paper products is a complex process which is 

carried out in two distinct phases: 

of the paper. 

a material suitable for use in paper, paperboard, and building materials. 

the pulping of the wood and the manufacture 

Pulping is the conversion of fibrous raw material, wood, into 

are 

te , 

The fibrous material ready to be made into paper is called pulp. There 

four major chemical pulping techniques: (1) kraft or sulfate, (2) sulf 

(3) semichemical, and (4) soda. 

.. 

Of the two phases involved in paper-making, the pulping process is 

largest'source of air pollution. Of the four major pulping techniques, 

the 

the 

kraft or sulfate process produces over 80 percent of the chemical pulp produced 

annually in the United States. 

4.1 KRAFT PULPING PROCESS 

1 

Pulp wood can be considered to have two basic components, cellulose and 

lignin. The fibers of cellulose, which comprise the pulp, are bound together 

in the wood by the lignin. To render cellulose usable for paper manufacture, 

any chemical pulping process must first remove the lignin. 

The kraft process for producing pulp from wood is shown in Figure 4-1. 

In the process, wood chips are cooked (digested) at an elevated temperature and 

pressure in "white liquor", which is a water solution of sodium sulfide (NaZS) and 

4-1 
T 

No nc o nd e rl s ab 1 es Verli Gases 

I- Condensate 

Weak Black Liquo 1\ 

Exhaust Gas Vent Gases 

ILIQUOR EFFECT 

I 1 OX I DATI ON EVAPORATOR 

I SYSTEM 

RECOVEPY 

FURNACE 

SYSTEM 

I 

I 

I 

I ----- 

STACK 

i I 

I 

Vent Gases I\ ( Na$03+Na2S) 

Vent’ Gases 

SMEl .T 

ter---) I DI SSOLVIFIG I TANK 

I 

I 

Green Liquor 

Y I 

TO treatment pondj 

Exha ‘c st Gases 

Fuel 

I 

CAUSTI CI ZI NG ‘L ~~~~~r - i TANK _. i<dimw 

Calcium 

carbonate 

mud 

(recycle to 

digester) 

Figure 4-1. KRAFT PULPING PROCESS 

4 -2 
sodium hydroxide (NaOH). 

the wood. 

liquor and washed with water. 

The white liquor chemically dissolves lignin from 

The remaining cellulose (pulp) is filtered from the spent cooking 

Usually, the pulp then proceeds through 

various intermittent stages of washing and possibly bleaching, after which 

it is pressed and dried into the finished product (paper). 

The balance of the process is designed to recover the cooking chemicals 

and heat. Spent cooking liquor and the pulp wash water are combined to 

form a weak black liquor which is concentrated in a multiple-effect evaporator 

system to about 55 percent solids. 

to 65 percent solids in a direct-contact evaporator, which evaporates water 

The black liquor can then be further concentrated 

by bringing the liquor in contact with the flue gases from a recovery furnace, or 

in an indirect-contact evaporator. The strong black liquor is then fired in 

a recovery furnace. 

provides heat for generating process steam and converting sodium sulfate (Na2S04) 

to Na2S. To make up for chemicals lost in the operating cycle, salt cake (sodium 

sulfate) is usually added to the concentrated black liquor before it is sprayed 

into the furnace. 

a molten smelt at the bottom of the furnace. 

Combustion of the organics dissolved in the black liquor 

Inorganic chemicals present in the black liquor collect as 

The smelt, consisting of sodium carbonate (Fla2C03) and sodium sulfide, 

is dissolved in water to form green liquor which is transferred to a 

causticizing tank where quicklime (CaO) is added to convert the sodium 

carbonate to sodium hydroxide. Formation of the sodium hydroxide completes 

the regeneration of white liquor, which is returned to the digester system. 

A calcium carbonate mud precipitates from the causticizing tank and is 

calcined in a lime kiln to regenerate quicklime. 

4-3 
4.2 DESCRIPTION OF LNDIVIDUAL PROCESS FACILITIES 

4.2.1 Digester System 

Mood chips are cooked with Bmfte liquor at aEiout 170 to 175°C; and at 

5 

pressures ranging from 6.9 to 9.3 x 10 pascals (100 to 135 psiq). Gases 

formed during digestton are vented to "re1 ieve" the digester and maintain 

proper cookinq pressure. 

and recover turpentine before venting. 

the heat and may be used in some other process. 

system: 

digester system, the contents of the digester are transferred to an atmospheric 

tank.uusua1ly referred to as a blow tank. 

cooking liquor containing the dissolved lignin is drained and the pulp is 

transferred to the initial stage of washing. 

from the blow tank are piped to a heat recovery unit. 

is not applicable to continuous digester systems. 

done in batch digesters, a1 though increasing numbers of continuous diqesters 

are being employed in the industry. 

4.2.2 Brown Stock Washer System 

At some mtlls the gases are first cooled to condense 

The condenser cooling water recovers 

There are two types of digester 

batch and continuous. At the end of the cooking cycle in a batch 

Here the major portion of the spent 

Steam and other qases that flash 

This blow of the diuester 

Most kraft pulping is presently 

Pulp from the digester system normally passes through the knotter which 

removes chunks of wood not digested during cooking. The pulp then is washed 

countercurrently with water in several sequential staqes. On leaving each 

stage, the pulp is dewatered on a vacuum filter, and the water drains into 

filtrate tanks. The washers are normally boded to collect the vapors that 

steam off the open washers. 

4.2.3 Multfple-Effect Evaporator System 

- Spent cooking liquor from the digester system is combined with the 6rom 

stock washer discharge to form weak (dilute] 61 ack 1 iquor. Mu1 tip1 e-effect 

4-4 
evaporators are utilized to concentrate the weak black liquor from an initial 

12 to 18 percent soltds to a final level of 40 to 55 percent solids. 

five or six evaporation units (effects] make up the system. 

consists of a vapor head and a heatina element. 

head of a previous effect pass to the heating element of the followinq effect. 

The effects are operated at successively lower pressures, which causes a 

decrease in the boiling point of the liquor. 

are condensed rapidly enough to maintain a high vacuum. 

condensers are used: direct contact condensers and surface condensers. Each 

type of condenser is equipped with a steam ejector to remove noncondensables. 

4.2.4 Recovery Furnace System 

Usually, 

Each effect 

Hot vapors from the vapor 

Vapors after the final effect 

Two types of barometric 

The purposes of burning concentrated black liquor in the kraft recovery 

furnace are: 

(c) to dispose of unwanted dissolved wood components in the liquor. 

instances, liquor of 60 to 65 percent solids content will burn in a selfsupporting combustion. 

(a) to recover sodium and sulfur, (6) to produce steam, and 

In most 

The recovery furnace theoretically is divided into three sections: the 

drying zone, the reducing zone, and the oxidizing zone. The black liauor is 

introduced to the furnace through spray guns located in the drying zone. 

heat in the furnace is sufficient to evaporate the remaininq water from the 

liquor. The dried solids fall to the hearth to form the char bed. 

The 

Combustion of the black liquor char begins on the hearth of the furnace. 

Air for combustion is supplied by a forced-draft system to the reducing and 

oxidizing zone of the furnace. 

convert sodium sulfate and other sodium-base sulfur compounds to sodium 

Since a reducinq atmosphere is required to 

4-5 
sulfide, only a portion of the air required for complete combustion is supplied 

to the char bed through the lower or primary air ports. The heat released by 

the combustion in the zone is sufficient to liquefy the chemicals in the char 

and to sustain the endothermic reduction. The liquefied chemical, or molten 

smelt, is continuously drained from the furnace hearth. 

Air is admitted through secondary and tertiary air ports above the primary 

zone to complete the combustion of the volatile gases from the char in the furnace. 

There are two main types of recovery furnace systems. The first type 

employs a direct-contact evaporator to provide the final stage of evaporation 

for the black liquor. 

direct contact with the furnace's exhaust gases. 

a conventional or direct-contact system. A conventional system is shown in 

This is accomplished by bringing the black liquor in 

This furnace type is called 

Figure 4-2. The second type of recovery furnace system employs an indirectcontact evaporator as the final evaporation stage; this type is called a 

noncontact direct-fired, or "low odor" system. A noncontact system is shown 

in Figure 4-3. The majority of the furnace systems in operation are the conventional 

type 9 

In addition, so-called cross-recovery is practiced at several mills. This 

practice is where the waste liquor from neutral sulfite semi-chemical (NSSC) 

cooking is combined with the black liquor from the kraft mill prior to burning. 

The inorganic content of the NSSC liquor will join the bulk of inorganics 

and occur in the smelt from the furnace, substituting for the sodium sulfate 

normally added in the kraft recovery cycle to cover losses of chemicals. 

4-6 
e--+ I I 

I--- 

ln 

ww 

I 

I 

I e-$% 

I 

- I --- 

1 

V 

ta 

I-- 

m 

I 

-1 1. IC 

4 -7 

*I-- 

X 

0 

L 

r 

w 

> 

S 

0 

V 

v 

0 

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I 

I------ .. --- 

I 

.I 

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f 

I 

I 

I 

I 

?Je 

h 

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1 

2 

aJ 

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u 

aJ 

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4-8 
4.2.5 Smelt Dissolving Tank 

The smelt dissolver is a large tank located below the recovery furnace 

hearth. 

on the floor of the furnace is dissolved in water to form green liquor in the 

tank. 

or liquid shatterjet system to break up the smelt stream before it enters the 

Molten smelt (sodium carbonate and sodium sulfide) that accumulates 

The tank is equipped with an agitator to assist dissolution, and a steam 

solution. Contact of the molten smelt with the water causes the evolution of 

large volumes of steam, which must be vented. 

The sodium carbonate (Na2C03) in the green liquor is converted to sodium 

hydroxide (NaOH) in the causticizing tank. 

(cao) to the liquor. 

with Na2C03; calcium carbonate precipitates out and is converted back into quicklime 

in a lime kiln. 

This is done by adding quicklime 

The quicklime forms sodium hydroxide, Ca(OH)2, which reacts 

4.2.6 Lime Kiln 

The lime kiln is an essential element of the closed-loop system that 

converts green liquor (solution of sodium carbonate and sodium sulfide) to white 

liquor. The kiln calcines the lime mud (calcium carbonate which precipitates 

from the causticizer) to produce calcium oxide (quicklime, CaO). The quicklime is 

wetted (slaked) by the water in the green liquor solution to form calcium hydroxide, 

Ca(OH)2, for the causticizing reaction. 

The kraft pulp industry typically uses large rotary kilns that are capable 

of producing 36 to 360 megagrams (40 to 400 tons) of quicklime per day. 

mud is fed in at the elevated end as a 55 to 60 percent solid-water slurry. 

mud is contacted by hot gases produced by the combustion of natural gas or fuel oil 

and proceeding through the kiln in the opposite direction. Large motors turn the 

entire kiln at low speeds (1-2 rpm), causing the lime to proceed downward thrGugh 

Lime 

The 

4-9 
the kiln toward the high-temperature zone (980 to 1090OC; 1800 to 2000°F) 

to discharge at the lower end. 

upper section, which may be equipped with chains or baffles to give the wet mud 

Setter contact with the gases. 

agglomerates into small pellets and finally is calcined to calcium oxide 

in the high-temperature zone near the burner. 

As the mud moves along, it dries in the 

As the lime mud moves down farther, it 

Fluidized bed calciners are presently being used at four kraft pulp mills, 

but the production rate of each kiln at this time is under 136 megagrams (150 tons) 

of lime per day. 

4.2.7 Black Liquor Oxidation System 

Black liquor oxidation is the practice of oxidizing the sodium sulfide in 

either weak or strong black liquor to sodium thiosulfate or possibly higher 

oxidation states. 

from the direct contact evaporator by producing a negligible sodium sulfide 

concentration in the black liquor. 

air is most often used. 

air at two mills. 

have been used in singular or multiple stages to provide intimate contact 

between the liquor and air. 

air at two mills. 

between the liquor and air. 

4.2.8 

Black liquor oxidation is designed to decrease the emissions 

In those mills which oxidize black liquor, 

However, molecular oxygen has been used instead of 

Sparging reactors, packed towers, and bubble tray columns 

Sparging reactors, packed towers, and bubble tray columns 

When digester and multiple-effect evaporator off-gases are condensed, 

some TRS gases are partially dissolved in the condensate. To prevent the 

release of kraft odor from the water treatment ponds, the TRS compounds can 

be stripped from the digester and multiple-effect evaporator condensates 

prior to being discharged to the ponds. 

are air stripping and steam stripping. 

(multiple tray) columns with U large countercurrent flow of air or steam. 

The two principal ways of stripping 

Stripping can be performed in multistage 

4-10 
REFERENCES FOR CHAPTER 4 

1. Atmospheric Emissions from the Pulp and Paper Manufacturing Industry, 

tPA-450/1-73-002, September 1973, page 5. 

Technical Bulletin No. 69, February 1974). 

(Also published by NCASI as 

4-1 1 

F 

5. EMISSIONS 

5.1 NATURE OF EMISSIONS 

The characteristic kraft mill odor is caused princioally bv a variable 

mixture of hydrogen sulfide, methyl mercaptan, dimethyl sulfide , and dimethyl 

disulfide. All of these gases contain sulfur, which is a necessary component 

of the kraft cooking liquor. 

Hydrogen sulfide emissions originate from the breakdown of sodium sulfide, 

which is a component of the kraft cooking liquor. Methyl mercaptan and 

dimethyl sulfide are formed in reactions with the wood component lignin. 

Dimethyl disulfide is formed through the oxidation of mercaptan groups derived 

from the thiolignins. 

5.1 . 1 Hydrogen Sul fide 

Hydrogen sulfide (H2S) is a weak acidic aas which Dartiallv ionizes in 

aqueous solution. The ionization proceeds in two staaes with the formation 

of hydrosulfide and, with increasing pH, sulfide ions 

H2S HS- + H+ S= + 2H+ (5-1 1 

increasing nH -+ 

Black liouor contains a hiah concentration of dissolved sodium sulfide 

in strongly alkaline solution. 

would hydrolyze to sodium hydrosulfide. Below oH 8, appreciable unionized 

hydrogen sulfide would form as the reaction equilibrium in equation‘ 5.-1 moves 

from right to left. 

If the pH were depressed, the sodium sulfide 

It is reported that at a pH of about 8.0, most hydrogen 

5-1 
sulfide forms hydrosulfide ions. 

there is very little dissolved hydrogen sulfide in the liquor. 

Consequently, in normal black 1 iauor conditions, 

1 

Due to the equilibrium between the hydrosulffde ion and water vapor, 

hydroaen sulfide gas can be stripped from black liquor at steam vents. 

could be, therefore, a significant concentration of H2S in the evaporator 

areas of the kraft mill. 

There 

Hydrogen sulfide is formed in the recovery furnace and lime kiln as the 

sulfur-containing compounds from the black liouor or lime mud are volatilized 

and reduced. Hydrogen sulfide generally represents the 1 araest aaseous emission 

from the kraft process. 

5. J .2 Methyl Mercaptan 

Methyl mercaptan (MeSH) is a reduced sulfur compound which is formed 

during the kraft cook by the reaction of hydrosulfide ion and the methoxy-lignin 

component of the wood: 2 

Lignin - OCH3 + HS- + MeSH + Lignin - 0- (5-2) 

Methyl mercaptan will also dissociate in an aqueous solution to methyl mercaptide 

ion. It is reported that this dissociation is essentially complete above a 

pH of 1~0,~ Methylmercaptan is, therefore, present in low concentrations as 

a dissolved gas in the black liquor. As the pH decreases, MeSH qas is evolved. 

Methyl mercaptan is primarily emitted from the digester relief and blow 

where it is formed, and from the brown stock washers where the pH of the liauor 

drops below the equilibrium point. 

concentration in the liquor diminishes. 

5.1.3 Dimethyl Sulfide 

Emissions decrease as the residual 

4 

Dimethyl Sulfide (MeSMe) is primarily formed through the reaction of methyl 

2 mercaptide ion with the methoxy-lignin component of the wood: 

5 -2 
Lignin - OCH3 + MeS--+ Lignin - 0- + MeSMe 

Dimethyl sulfide may also be formed by the disproportionation of methyl mercaptan. 

At normal liquor temperature (150-2OO'IF) it is highly volatile. It does not, however, dissociate as hydrogen sulf.ide and methyl mercaptan do. 

5.1.4 Dimethyl Disulfide 

Dimethyl disulfide (MeSSMe) is formed by the oxidation of methyl mercaptan 

throuqhout the recovery system, especiallv in oxidation towers: 

4 MeSH + 02 2 2 MeSSFle + 2 H20 (5-4) 

Dimethyl disulfide has a hiqher boiling point than any of the other compounds 

and its retention in the liquor is therefore greater. 

5.2 UNCONTROLLED TOTAL REDUCED SULFUR EMISSIONS 

Uncontrolled total reduced sulfur (TRS) emissions are listed in Table 5-1 

for each of the TRS sources under consideration. These emission rates are for 

a 907 megagrams per day (1000 tons per day) kraft pulp mil 1. 

also lists typical gas volume rates for each source. 

5.2.1 Recovery Furnace System 

Table 5-1 

TRS emissions are generated both in the furnace and in the direct-contact 

evaporator. 

hundred parts per million (ppm) and as low as 1 ppm depending on the furnace 

design and operation. 

quantity and distribution of combustion air, rate of solids (concentrated black 

liquor) feed, spray pattern and drpplet size of the liquor fed, turbulence in 

the oxidation zone, smelt bed disturbance, and the combination of sulfidity 

and heat content value of the liquor fed. The impact of these variables on 

TRS emissions is independent of the absence or presence of a direct-contact 

evaporator. 

The furnace-generated TRS concentration is as hiah as several 

Recovery furnace emissions are affected by the relative 

TRS emissions generated in the direct-contact evaporator depend largely 

on the concentration of sodium sulfide in the black liquor. Acidic gases such 

5-3 
as carbon dioxide in the flue gas can change the black liquor equilibrium, 

resulting in the release of increased quantities of hydrogen sulfide and methyl 

mercaptan. 

Wcuh'trolled TRS emissions from a conventional recovery furngce system 

range ftwr 0.75 to 31 grants per kilogram (1.5 to 62 pounds per ton) of air 

dried pulp and average about 7.5 grams per kilogram (15 pounds per ton) of air 

dried pulp (ADP) .6 This is an averaae of about 550 ppm. 

5.2.2 Digester System 

The noncondensable gases from the relief system and the blow tank vent 

contain TRS concenttations as high as 30,000 ~pm.~ Both streams are sometimes 

referred to as digester "noncondensables". 

are mainly methyl mercaptan, dimethyl sulfide and dimethyl disulfide. 

TRS compounds formed in the diqester 

Uncontrolled 

TRS emissions from a digester system range between 0.24 and 5.25 g/kq ADP 

(0.47 and 10.5 lb/ton ADP) and average about 0.75 g/kg ADP (1.5 lb/ton ADP) 

at a concentration of 9,500 ppm.' Operating variables that affect diqester 

TRS emissions include the black liquor recycle rate, cook, duration, cooking 

liquor sulfidity (percentage of sodium sulfide to total alkali, Na2S and NaOH, 

in white 1 iquor) , and residual a1 kal i level . 

5.2.3 Mu1 tiple-Effect Evaporator System 

The noncondensable gases from a mu1 tiple-effect evaporator (MEE) system 

consist of air drawn in through system leaks and reduced sulfur compounds that 

were either in the dilute black liquor or formed during the evaporation process. 

TRS emissions from the MEE system are as high as 44,000 ppm.8 Uncontrolled 

TRS emissions from a MEE system average about 0.5 g/ka ADP (1 .O lb/T ADP) at 

a concentration of 670C ppm. 

- 

8 

The type of condenser used can influence the concentration of TRS emissions. 

Certain types of condensers (e. g. direct-contact) allow the noncondensabl e aases 

and the condensate to mix, which results in a limited quantity of hydroqen 

5 -4 
Table 5-1. TRS EMISSIONS FROM AN UNCONTROLLED 907 GRAMS PER DAY 

(1000 TONS PER DAY) KRAFT PULP MILL(^) 

Typical 

F1 ow Rate 

Exhaust Gas TRS Emission Ranqe Average(2) TRS Emission Rate 

Source m3/s (acfm) ppm g/ka ADP (lb/T ADP) ppm q/s(lb/hr) g/kq ADP(lb/T ADP) 

Recovery Furnace 

Digester System 

Mu 1 ti pl e- Ef f ect 

Evaporator Sys tem 

Lime Kiln m 

Brown Stock 

Washer System 

Black Liquor 

Oxidation System 

Smel t Dissolving Tank 

Condensate Stripper 

System 

212(450,000) 

3(6,200) 

1(2,200) 

37 (79,200) 

71 (1 50,000) 

14( 30,000) 

27 (58,100) 

2 (4,000) 

18-1 303 0.75-31 (1.5-62) 

1525-30,000 0.24-5.3 (0.47-1 0.5) 

92-44,000 0.01 5-3.2(0.03-6.3) 

3-61 3 0.01 -2.1 (0.02-4.2) 

- 0.005-0.5 (0.01 -0.9) 

3-335 0.005-0.37( 0.01 -0.73) 

5-81 1 0.007-1 .9( 0.01 3-3.70) 

- - 

550 

9,500 

6,700 

170 

30 

35 

60 

5000 

7.5( 15 .O) 

0.75t1.5) 

0.5(1 .O) 

0.4(0.8) 

0.15( 0.3) 

0.05(0.1) 

0.1 (0.2) 

1.0(2.0) 

-- 

(1 )Uncontrolled emission data for condensate strippers were obtained from Reference 13. 

were obtained from Reference 5. 

(*)Average values listed are calculated from data listed in P.eference 5. 

Reference 5 to evaluate the operation of the units for which data were reported. 

Data for all other sources 

Insufficient information was available in 
sulfide and methyl mercaptan gases dissolved in the water. This reduces the 

TRS concentration from the system, but increases the sulfide level in the 

condensate. 

the TRS concentration from the mu1 tiple-effect evaporators. 

levels result in higher TRS emissions. TRS levels increase with decreasing pH levels. 

5.2.4 Lime Kiln 

Sulfidity and pH of the weak black liquor also have an effect on 

Higher sulfidity 

TRS emissions can be generated in the lime kiln proper and in the downstream 

scrubber which is normally installed to control particulate emissions. 

TRS emissions originating in the lime kiln are affected by the oxygen 

content of the exhaust, the kiln length to diameter ratio, the lime mud sulfide 

cont.int, cold-end exit gas temperature, and simultaneous burning of sulfur 

bearing materials contained in the lime mud (e.g., green liquor dregs, the 

impurities resulting from clarifying the green liquor). 9 

If digester and evaporator condensates are used as lime kiln scrubber water, 

reduced sulfur compounds can be stripped into the exist gas stream. If the 

scrubbing liquor contains sodium sulfide, as it does in Some installations, 

H2S may be released in the scrubber as a result of the equilibrium shift 

caused by the absorption of C02 in the liquor. 

Uncontrolled TRS emissions from a lime kiln average about 0.4 g/kg ADP 

(0.8 lb/T ADP) at a concentration of 170 ppm. TRS emissions from lime kilns 

range between 3 and 600 ppm (0.02 to 4.2 lb/T ADP) depending on combustion 

characteristics of the individual kilns. 

5.2.5 Brown Stock Washer System 

10 

TRS emissions from the brown stock washers arise primarily from the 

vaprization of the volatile reduced sulfur compounds. TRS compounds emitted 

are principally dimethyl sulfide and dimethyl disulfide. 

5 -6 
Uncontrolled TRS emissions from the brown stock washer system average 

about 0.14 g/kg ADP (0.27 lb/T ADP) at a concentration of 30 ppm. 

0.05 g/kg ADP (5-37 ppm) are emitted from the hood vent and about 0.08 g/kg ADP 

(240-600 ppm) are emitted from the filtrate tank (under) vent. 

About 

11 

Brown stock washer TRS emissions are affected by the wash water source, 

water temperature, degree of agitation and turbulence in filtrate tank, and 

blow tank pulp consistency.” TRS emissions will increase significantly if 

contaminanted condensate from the digester and evaporator systems are used for 

washing. 

the TRS during the washing. 

5.2.6 Black Liquor Oxidation System 

the reduced sulfur compounds from the black liquor by air passing through the 

liquor. Uncontrolled TRS emissions (principally dimethyl sulfide and dimethyl 

disulfide) are in the range of 0.005 to 0.37 g/kg ADP (about 3 to 335 ppm) 

and average 0.05 g/kg ADP (35 ppm).” Oxidation systems that use only molecular 

oxygen have the advantage of emitting virtually no off-gases because the 

total gas stream re,acts in the sparge system. 

Higher temperatures and agitation result in increased stripping of 

TRS emissions from the oxidation system are created by the stripping of 

Primary factors affecting TRS emissions from black liquor oxidation 

systems are the inlet sulfide content, the temperature of the black liquor, 

residence time, and the air flow rate per unit volume. TRS emissions tend to 

increase for higher liquor temperatures and greater air flow rates because of 

greater volatility of the gases and stripping action of the air, respectively. 

TRS emissions also tend to increase with increasing sulfide concentrations in 

the incoming black liquor and with increashg residence time. 

5.2.7 Smelt Dissolving Tank 

Because of the presence of a small percentage of reduced sulfur compounds 

in the smelt, some of these odorous materials escape the tank with the flashed 

5 -7 
steam. 

as low as non-detectable. 

Uncontrolled TRS emissions are as high as 2.0 g/kg ADP (871 ppm) and 

13 The average is about 0.1 g/kg ADP (60 ppm) . 

Several factors affect the TRS emissions. Among these are the water 

used in the smelt tank, turbulence of the dissolving water, scrubbing liquor 

used in the particulate control device, pH of scrubbing liquor, and sulfide 

content of the particulate collected in the control device.” 

contaminated condensate in the smelt tank or the scrubber can result in the 

The use of 

stripping of TRS compounds into the gas stream. Turbulence can increase the 

stripping action. Incr2ased H2S formation can occur with a increase in sulfide 

content of the scrubbing liquid and a decrease in pH of the scrubbing liquor. 

5.2.8 Condensate Stripping System 

Presently there are only five condensate strippers in operation in the 

U.S. kraft pulp industry. Actual TRS emission data are unavailable, but TRS 

emissions from condensate strippers are expected to be high because the condensate 

contains high concentrations of dissolved TRS compounds.14 The stripping 

efficiency is greater than 95 percent.14 Uncontrolled TRS emissions are 

estimated to be about 1 g/kg ADP (5000 ppm) from a condensate stripping system. 15 

5.3 TYPICAL TRS EMISSIONS 

Typical controlleci TRS emissions are listed in Table 5.2 for each of the 

sources under consideration. These values represent average TRS emissions 

from existing facilities, based on the information listed in Appendix A. 

Appendix A lists emission rates for five sources (recovery furnaces, lime kilns, 

digesters, mu1 tiple-effect evaporators, and brown stock washers) at each kraft 

pulp mill in the United States. 

the literature, state pollution contrul agencies, and the kraft pulp mills. 

Information in Appendix A was obtained from 

Emission rates for uncontroll ed sources are average uncontrolled values (See 

section 5.2) for the industry, except where actual levels are known. Controlled 

5 -8 
Table 5-2. TRS EMISSIONS FROM THE EXISTING KRAFT PULP INDUSTRY 

Average Uncontvc led Level Percent Capacity Typical CBntrol led Level Average National Emissions 

ppm (lb/T ADP) "mrams glkg AD g/kg ADP g/kg ADP 

Source PPm (lb/T ALP) Controlled(1) PPm (lb/T ADP) 

Recovery Furnace 

Digester System 

Mu1 tiple-Effect 

Evaporator Sys tem 

Lime Kiln 

Brown Stock 

& Washer System 

Black Liquor 

m 

Oxidation System 

Smelt Dissolving Tank 

Condensate Stripper 

System 

550 

9500 

6800 

170 

30 

35 

60 

5000 

7.5 

(15.0) 

0.75 

(1.5) 

(1 -0) 

(0 -8) 

(0.3) 

0.5 

0.4 

0.15 

0.05 

(0.1) 

(0.2) 

(2.0) 

0.1 

1 .o 

88.7 

58.4 

58.6 

28.2 

2.8 

2.1 

100 

5-70 

5 

5 

5-40 

5 

0-1 0 

- 

5 

0.075-1.05 

(0.1 5-2.1 ) 

0.01 

(0.02) 

(0.02) 

0.01 

0.01 25-0.1 

(0.025-0.2) 

0.01 

(0.02) 

0.0-0.01 

(0.0-0.02) 

- 

0.01 

(0.02) 

92 

4050 

2920 

130 

30 

35 

60 

500 

1.25 

(2.5) 

0.32 

(0.64) 

0.22 

(0.43) 

0.31 

(0.62) 

0.15 

(0.3) 

0.05 

(0.1) 

(0.2) 

(0.22) 

0.1 

0.11 

39 , 000 

10,000 

6,700 

9,700 

4,420 

1,470 

2,940 

0.4 

(l )Percentage based on mills controlled by existing state regulations, plus information collected 

during previous surveys. 
levels listed are the actual levels where these were known; otherwise the 

applicable state standard is listed. 

Table 5.2 also gives an estimate of the percentage of facilities presently 

controlled, and the TRS level to which they are most frequently controlled. 

These estimates on the percent of facilities controlled are based on existing 

or soon to be adopted state regulations. The estimates also include information 

obtained from various surveys of the industry on controlled facilities which 

are not presently covered by state regulations. 

In most cases the typical emissions from existing facilities are equal 

to or near the uncontrolled levels. 

emissions from the brown stock washers, smelt dissolving tanks, lime kilns, 

and black liquor oxidation system. 

to some extent by a large percentage of the industry. 

emissions from these sources are discussed in the following sections. 

A few mills presently control TRS 

The other TRS sources have been controlled 

The typical TRS 

5.3.1 Recovery Furnace System 

TRS emissions from direct contact systems depend on the design and operation 

of the recovery furnace and, if utilized, an oxidation system. A survey of 

32 recovery furnace systems where black liquor oxidation is not used shows TRS 

emissions ranging from 35 to 1300 ppm, regresentlng 0.75 to 31 g/kg ADP (1.5 to 

62 lb/T ADP). 

units that utilize black liquor oxidation indicates a broad TRS emission range 

of 0.1 to 13.0 g/kg ADP (0.2 to 25.9 lb/T ADP), with an average value of 3.7 

g/kg ADP (170 ppm).16 TRS emissions from non-contact systems are usually 

confined to a narrow range of about 0.015 to 0.15 g/kg ADP (1 to 11 ppm) . 

The average is 7.7 g/kg ADP (15.4 1 b/T ADP). A survey of 17 

- Based on Appendix A, it is estimated that TRS emissions from about 89 

percent of the existing furnaces are either controlled by black liquor oxidation 

5-1 0 
or have been replaced with or converted to a non-contact system. 

It is also estimated that the average national emission level is 1.25 g/kg ADP 

(92 PPmv). 

5.3.2 Digester and Mu1 tiple-Effect Evaporator Systems 

The digester and mu1 tiple-effect evaporators wi 11 be considered together 

because their emissions are normally combined for treatment. Until recently, 

the noncondensable gases were in most cases vented to the atmosphere uncontrolled. 

However, several mills now incinerate the gases to control odors. Most CmOn1Y, 

the gases are burned in the lime kiln. 

reduce TRS emissions to less than 5 ppm (0.0075 g/kg ADP). 

thit approximately 58 percent of the mills are incinerating these gases or are 

installing systems to incinerate these noncondensables. White liquor (caustic) 

scrubbers are used at a few mills. These scrubbers are only effective in 

removing hydrogen sulfide and methyl mercaptan. TRS emissions from these 

scrubbers are estimated to be aboht 0.5 g/kg ADP (1 lb/T ADP). 

Based on EPA tests,17 incineration can 

It is estimated 

Based on Appendix A, the average national emission rate from digester 

systems is calculated to be 0.32 g/kg ADP (0.64 lb/T ADP). The average 

national emission rate from mu1 tiple-effect evaporators is calculated to be 

0.22 g/kg ADP (0.43 lb/T ADP). 

controlled to 5 ppm and 42 percent being uncontrolled. 

5.3.3 Lime Kiln 

These values are based upon 58 percent being 

TRS emissions from a lime kiln installation are dependent on the operation 

of the kiln, the mud washing efficiency, and the type of water used in the 

scrubber. Only about 28 percent (See Appendix A) of the kilns are actually 

operated to control TRS emissions. This percentage is mostly based on kilns 

affected by existing state or local regulations. Based on this percentage of 

5-1 1 
controlled kilns, the calculated average national emission rate for lime kilns 

is 0.31 g/kg ADP (130 ppm). 

5.3.4 Condensate Stripping System 

All the condensate strippers in operation are controlled for TRS emissions. 

Incineration is the control technique used at four mills. The TRS emissions 

from these sources are estimated to be 5 ppm as mentioned in section 5.3.2. 

A caustic scrubber is utilized at the remaining one mill, but no data is 

available on the TRS emissions. 

The average national emission rate is estimated to be 0.11 g/kg ADP 

(0.22 lb/T ADP). This is based on 5 ppm TRS being achieved at 4 mills and 

50 percent control at the mill that uses a caustic scrubber. 

5.3.5 Brown Stock Washer Systems, Black Liquor Oxidation Systems, and 

Sinel t Dissolving Tanks 

These three sources are generally not controlled for TRS emissions. 

However, two U.S. mills incinerate the vent gases from the brown stock washer 

systems. Two other U.S.mills use molecular oxygen in their black liquor 

oxidation system, which results in no vent gases and no TRS emissions. 

mill is controlling TRS emissions from the brown stock washers by a chlorine 

!&e 

scrubber. One other mill is controlling TRS emissions from their brown stock 

washers and black liquor oxidation system by a chlorine gas injection system. 

5-12 
REFERENCES FOR CHAPTER 5 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12-. 

13. 

Shih, T. T., Hrutfiord, B. F., Sarkanen, K, V., and Johanson, L. N., 

Hydrogen Sulfide Vapor-Liquid Equilibrium in Aqueous Systems As a 

Function of Temperature and pH, TAPPI, 50(12), 630-4, 1967. 

McKean, W. R., Hrutfiord, B. F., Sarkanen, K. V., Kinetic Analysis of 

Odor Formation in the Kraft Pulping Process, TAPPI, 48(12), 699-703, 1965. 

Shih, T.>T., Hrutfiord, B. F., Sarkanen, K. V., Johonson, L. N., 

Methyl Mercaptan Vapor-Liquid Equilibrium in Aqueous Systems As a 

Function of Temperature and pH, TAPPI, 50(12), 634-8, 1967. 

Control of Atmospheric Emissions in the Wood Pulping Ifidustry, Environmental Engineering Inc., and J. E. Sirrine Company, Final Report, EPA 

Contract No. CPA-22-69-18, March 15, 1970. 

Atmospheric Emissions from the Pulp and Paper Manufacturing Industry, 

EPA-450/1-73-002, September 1973. 

Bul lehin No. 69, February 1974). 

Reference 5, Table 14. 

Reference 5, Table 3. 

Reference 5 , Table 7. 

Buggested Procedures for the Conduct of Lime Kiln Studies to Define 

Emissions of Reduced Sulfur Through Control of Kiln and Scrubber Operating 

Variables, NCASI Special Report No. 70-71 , January 1971. 

Reference 5. Table A-5. 

Factors Affecting Emission of Odorous Reduced Sulfur Compounds from 

Miscellaneous Kraft Process Sources, NCASI Technical Bulletin No. 60, 

March 1972. 

Reference 5, Table 21. 

Reference 5. 

(Also pub1 ished by NCASI as Technical 

5-1 3 
14. Butryn, 6. L. and Ayers, K. C., Mead Experience in Steam Strippina 

Kraft Mill Condensate, presented at TAPPI Environmental Conference, 

May 14-16, 1975. 

15. Air Emission - Control Program For Hoerner Waldorf Corporation Mill 

Expansion Pissoula, Montana, submitted by Hoerner Waldorf Cornoration 

to Montana State, March 12, 1974. 

16. Reference 5, Table 15. 

17. Malodorous Reduced Sulfur Emissions From Incineration of Non-condensable 

Off-gases, EPA Test Report 73-KPM-1A. 

5-14 
6. CONTROL TECHNLQUES FOR TRS FROM KRAFT PULP MILLS 

6.1 ALTERNATIVE CONTROL T€CHNIQU€S 

The various control techniques that have been or can be applied 

to the emission sources affected by NSPS are discussed in this section. 

The affected sources are the recovery furnace, digester system, 

multiple-effect evaporator system, lime kiln, brown stock washer 

system, 6lack liquor oxidation system, smelt dissolving tank, and 

condensate s tri pper system. The appl i cabi 1 i ty and effecti veness of the 

control techniques when retrofitted on existing facilities is also 

discussed. Table 6-1 summarizes the control techniques and corresponding 

TRS levels achievable for each source of TRS. Section 6.2 discusses 

alternative control systems for entire kraft pulp mills. Retrofit 

models are presented wkich permit estimates to be made of required 

costs for retrofitting existing facilities with the a1 ternative 

control systems. 

6.1 ..l Recovery Furnace System 

TRS emissions from a recovery furnace system can originate in the 

recovery furnace itself, or in the direct contact evaporator if this 

type of evaporator is, used. 

have direct contact evaporators. About 75 percent of the new recovery 

furnaces that have been installed in the last 5 years are, however, of 

the non-contact design. 

Most existing recovery. furnace systems 

In these furnaces, the furnace flue gases 

- never directly contact the black liquor and TRS cannot be formed in the 

6 -1 
Table 6-1. TECHNIQUES FOR CONTROLLING TRS EMISSIONS 

FROM SOURCES IN A KRAFT PULP MILL 

Control Achievable TRS 

Source Technique Leve 1 

Recovery furnace 

Di ges ter system 

Mu1 tiple-effect 

evaporator system 

Lime ki In 

Brm stock 

washer system 

Black liquor oxi dation system 

Smelt dissolving 

tank 

Condens ate s tri ppi n g 

system 

Process controls + 

bl ack 1 iquor oxidation 

Process controls 3. 

conversion to non-contact 

evaporator 

Caus ti c scrubbing 

Incl nerati on 

Caustic scrubbing 

In ci nera ti on 

Process controls 

Process controls + good 

mud washing 

Process controls, good mud 

washing + caustic scrubbing 

Inci nerati on 

Molecular oxygen 

Incineration 

Fresh water usage 

Caus ti c scrubbing 

Incineration 

20 ppm (Old desi n' 

5 ppm (New desi n2 

furnaces 3 

furnaces 3 

furnaces 3 

furnaces 3 

25 ppn (Cross recovery 

20 ppm (Old desi n 

5 ppm (New desi n 

furnaces ) 

25 ppm (Cross recovery 

furnaces ) 

7,000 ppm3 

5 Ppm 

350 ppm3 

5 Ppn 

40 Ppm 

20 Ppm 

5 Ppm 

0 PPm 

5 PPm 

0.0084 g/kg BLS 

- 

5 PPm 

lOld - design furnaces are defined as furnaces without welded wall or membrane wall 

2New - design furnaces are defined as furnaces with welded wall or membrane wall 

3Calcul ated based upon scrubber removing only hydrogen sulfide and methyl mercaptan 

construction or emission-control designed air systems. 

construction and emission-control designed air systems. 

and using reference 5 to determine percent of hydrogen sulfide and methyl mercaptan 

Present In vent stream. 

6-2 
evaporator. 

1967. 

The non-contact furnace was first introduced in 

Several operating and design variables that have Some effect on, 

or relationship to, the generation of TRS emissions, in a recovery 

furnace have been identi-fied. These include the quantity and manner 

of introduction of comhustion air, the rate of solids (concentrated 

black liquor) feed, the degree of turbulence in the oxidation zone, 

the oxygen cortent of the flue gas, the spray pattern and droplet 

size of the liquor fed the furnace, and the degree of disturbance of 

the smelt 

absence or presence of a direct contact evaporator. 

evidence that sulfide content of the liquor combusted in the furnace 

The effect of these variables is independent of the 

There is no 

bears any relationship to the TRS emissions from the recovery furnace. 

This is not to be confused, however, with sulfur compounds generated 

or stripped in a direct contact evaporator. 

The age of existing furnaces has been reported to be a significant 

indicator of the furnace's ability to control TRS emission^.^ 

typical life of a recovery furnace is considered to he 25 

GL,ierally,the 

controls and instrumentation that assist the operator in maintaining 

close control of the process. 

recent manufacturers' impravements., such as new. means of introducing 

air, flexibility in distributing air in the furnace and means to change 

air velocity at injecti-on ports. 

was made to recovery furnaces in late 1964. 

(The 

age reflects an absence or lack of refinement in 

Also, older furnaces may not incorporate 

6 Furthermore, a major design change 

This change consisted of 

6 -3 
installing a membrane between the wall tubes located in front of the 

furnace's wall insulation. This design change made the furnace airtight. The wall insulati.on on furnaces without this membrane wall 

concept tends to deteriorate. 

This in turn affects. the combustion in the furnace and reduces 

significantly the capability of the operator to control TRS emissions. 

These older recovery furnaces could be modified to incorporate 

these new design features but the modifications wuld be extremely 

expensive. 

made. 

This allows air to leak into the furnace. 

7 

HoMver, changes in operating procedures can more easi ly be 

Tkre are two control techniques to reduce TRS emissions from the 

direct contact evaporator: black 1 iquor oxidation and conversion to 

a non-contact evaporator. 

between the combustion gases and black liquor that normally generate 

hydrogen sulfide. 

Na2S203 in the black liquor before it enters the direct contact 

evaporator. 

contact between furnace gases and black liquor is eliminated, and 

hydrogen sulfide formation is prevented. 

Black 1 iquor oxidation inhibits the reactions 

This is accomplished by oxidizing the Na2S to 

In converting to a non-contact evaporator, the direct 

There are several modes. of operation of hlack liquor oxidation 

systems.. The black liquor is sometimes oxidized before being 

concentrated in the mu1 tiple-effect evaporators (weak black liquor 

oxidation), sometimes following evaporation [strong black liquor 

oxidation) and sometimes both, before and after. Air is the normal 

oxidizing agent, 6ut molecular oxygen is also used Khen available on 

site. Air sparging reactors are the most comnon units, but 

6-4 
packed towers and buhhle tray towers are also used. 

In modifying an existing recovery furnace with a direct contact 

evaporator to a non-contact design, a black liquor evaporator 

Cconcentrator) and a second feed Mater economizer is necessary. 

addition, elimination of the existing direct contact evaporator will 

result in an increased particulate concentration discharge from the 

furnace system into tfie particulate control device. To maintain 

particulate emissions at the original leve1,it may be necessary 

to replace the existing collector with a new higher efficiency 

precipitator or ins,tall an additional secondary collector, 

In 

This 

conversion to a non-contact design has been accomplished by at least 

Two pulp mills. 

At one recovery furnace system, erected in 1966, where the 

conversion was made, TRS emissions decreased from approximately 400 

ppm to about 10 ppm.’ Modifications also included changes to the 

operation of the furnace, such as oxygen content and air distribution. 

Therefore, a portion of the TRS reduction is attrihutable to decreased 

emissions of TRS from the furnace system. 

TRS emissions from direct contact systems depend on the design 

and operation of the recovery furnace and the black liquor oxidation 

system. 

hetween oxidation efficiency and TRS emissions, presented in Table 6-2. 

Since these samples were taken at stacks on new recovery furnaces, the 

furnace TRS contribution i.s assumed to be negligible.” The data 

An analysis. of 200 s,tack gas samples shoved the relation 

show a clear relationship between oxidation efficiency and TRS 

6 -5 
Table 6-2 

Relationship of Oxi\dati,on Effi~ciency and t$S Emis,si.ons 11 

Oxi,dati.on Nuroher tL,S Emi\ssions 

Efficiency, of g ~s/Ks'Pulp"-~ - ' - Lb S/Ton Pulp 

Percent Sam? 1 es - Max -. Min -. Mean & & - Mean 

80-85 

85 -90 

8 

15 

4.1 0.75 2.3 8.1 1.5 4.6 

3.0 Q.05 1.6 6.0 0.1 3.2 

9a-94 29 3.3 0.25 1.2 6.6 0.5 2.4 

94-96 18 2.2 0.05 0.9 4.3 0.1 1.8 

96-98 

98-99 

15 

19 

1.4 0.05 0.65 2.8 0.1 1.3 

1.1 o.a 0.35 2.1 0.0 0.7 

99-1 oa 96 1.6 0.0 0.2 3.2 0.0 0.4 

6 -6 
emissions. 

eliminated by conversion to a non-contact type system. 

Emissions from the direct contact evaporator will be 

TRS emission tests conducted during the NSPS development program 

indicate that TRS emissions from new recovery furnaces can be control led 

to at least 5 ppm.12 During the NSPS program, three recovery furnaces 

(two direct contact systems and one non-contact system) were tested 

by EPA. 

ppm (6 tests, each 4-hours) 0.6 ppm (-6 tests, each 4-nours), and 

3.9 ppm (5 tests, each 4-hours). 

greater Cabout 7 ppm) than 5 ppm. 

TRS emissions averaged from the individual furnaces are 1.4 

Only one 4-hour test showed emissions 

One furnace manufacturer indicates that many recovery furnaces built 

since 1965 are basically the same design as new furnaces built today, and 

that these should also be capable of achieving 5 ppm TRS with good process 

control and either black liquor oxidation or conversion to a non-contact 

evaporator. These exi s ti nq recovery furnaces , defined as "new des i an" 

furnaces, were desiqned for low TRS emissions (i .e., incorporates manufacturer's 

improvements) and will have stated in their contracts that these furnaces 

were constructed with air pollution control as an objective. Recovery 

furnaces, mainly those built before 1965, that were not constructed with 

air pollution control as an objective, have a somewhat different desisn, 

as mentioned previously, and are not capable of achievinq 5 ppm TRS 

(4-hour average basis). These furnaces, defined as "old desiqn" furnaces, 

14 

6-7 
can generally achieve about 15 to 20 ppm TRS with good process control 

and black liquor oxidation or conversion to a non-contact evaporator. 

This TRS level (15 to 20 ppm) is presently being achieved by existing 

recovery furnaces (see AppendixB) , many built before 1965, in those 

16 

states which have TRS regulations of 17.5 ppm (daily averaqe). Some 

existing furnaces may have difficulty achieving even this level (20 ppm) 

if they are operating at a much hiqher firinq rate than oriqinally 

designed or do not have sufficient combustion control capability. 

15 

Cross recovery liquors are somewhat different than straiqht kraft 

liquor, and, therefore, it is possible that the TRS emissions from a cross 

recovery furnace are not controllable to the same degree as are those from 

the straight kraft furnace. 

may be higher from cross recovery furnaces.17 The first relates to the 

sulfur content of the liquor which is higher with this process than in 

straight kraft processes. 

of the black liquor is lower than found in straight kraft mills. 

because the NSSC process gives higher pulp yields than the kraft process 

and, as a consequence, the spent liquor associated with the YSSC process 

contains less organic content. 

with kraft black liquor. 

excess oxygen available in cross recovery furnaces to oxidize the relatively 

large quantities of volatile sulfur compounds given off as a consequence 

of the heavy sulfur loading and lower furnace operatina temperatures. 

enough excess oxyqen is supplied to completely oxidize all volatile sulfur 

compounds, a sticky dust problem will develop which can plug up the 

precipitator and render furnace operation impossible. 

There are three reasons why TRS emissions 

In cross recovery operations, the heat content 

This is 

Therefore, its Rtu value is lower as compared 

The third reason pertains to the restriction on 

If 

6-8 
Based on a study18 conducted on one cross-recovery furnace, cross-. 

recovery furnaccs which experience arwn liquor sulfidities in excess of 

28 percent and liquor mixtures of more than 7 percent NSSC on an air dry 

ton basis can not achieve the same TRS levels as straight kraft recovery 

furnaces. Emission data reported in the study indicate that TRS emission 

levels of 25 ppm, corrected to 8 percent oxygen, can be achieved from 

we1 1 -control led cross-recovery furnaces. 

A recently developed control technique for recovery furnaces is a1 kal ine 

adsorption with carbon activated oxidation of the scrubbing solution. 

Pilot plant studies indicate that this technique can reduce TRS emissions 

from 20 to 2500 ppm to between 1 and 10 ppm.” Reduction in particulate and 

SO 

to control TRS emissions on those older existing furnaces or cross recovery 

furnaces which do not have the combustion control capability for low TRS 

emissions. 

load on older existing furnaces that are not capable of achievinq the 

necessary TRS regulations. 

emissions are also reportedly achieved. This technique could be used 2 

This technique could prevent the need to replace or reduce the 

6.1.2 Digester and Mu1 tiple-Effect Evaporator Systems 

The digesters and mu1 tiple-effect evaporators will be considered 

together because non-condensable gases discharged from these two 

sources are nermally combined for treatment. 

incinerating the gases. to destroy odors. 

burned in the lime kiln. 

are also used, either as hackup for the kiln when it is shutdown, or 

as the full-time control deyice. 

At least half the mills are 

Most commonly, the gases are 

However, a few special gas-fired incinerators 

Retrofitting an exi.sting mill to handle and incinerate these 

non-condensable gases is apparently no significant problem. 

it is, simply a matter of ducting the gases to the kiln or incinerator 

and i ns tal 1 i ng necessary condensers and gas hol ding equipment . 

Generally, 

- 

The 

6-9 
non-condensable gases are added to the primary air to the kiln. 

This retrofit situation has now been performed at over sixty mills. 

The blow gases from batch digesters are generated in strong 

hursts that normally exceed the capacity of the lime kiln. 

reason, special gas handling equipment has been developed to make 

the gas flows more uniform?OAdjustable volume gasholders, with 

movable diaphragms or floating tops, receive the gas surges, and a 

small steady stream is 61ed to the kiln. 

gasEs form exploeive mixtures in air, possible explosion hazards 

have been minimized by the development of appropriate gasholding 

For this 

Although the non-condensable 

.Systems, flame arrestors and rupture disks in the gasholding ducts, 

and flame-out controls at the lime kiln. Incineration of these 

the lime kiln is particularly 

red to achieve effective 

gases in existing process equipment 

attractive since no additional fuel 

emission control. 

Scrubbers are used at a few ex 11s. Uhite liquor, the 

usual scrubbing medium, is effective for removing hydrogen sulfide and 

methyl mercaptan, but not dimethyl sulfide or dimethyl disulfide. 

At least 3 mills 

cl1 recover sulfur, (2) condense steam, and (3) remove turpentine 

vapors and mist, therehy reduci.ng the explosion hazards. 

21 

scrub the noncondensable gases before incineration to: 

Combustion of noncondensahle gases in a lime kiln or gas-fired 

i.ncineaator provides nearly complete destruction of TRS compounds. 

During an EPA test (conducted for NSPS) on a separate incinerator 

- burning noncondensahles from a digester system and a multiple effect 

such as 

is requ 

sting m 

6-1 0 
evaporator system, the residual unburned TRS was less than 5 ppm 

(0.01 g/kg ADP) The TRS test results (4-hour averages) of the 

four tests conducted ranged betKeen 0.5 and 3.Q ppm, and averaged 

1.5 ppm (dry gas basis). 

operating at 1000°F (measuredl with a calculated retenti.on time for 

the gases of at least 0.5 seconds. 

22 . 

During the tests, the incinerator was 

Scrubber efficiencies are much lower than properly operated 

incinerators because only hydrogen sulfide and methyl mercaptan 

react with the alkaline medium. 

gases is highly variable, but on the average hydrogen sulfide and 

methyl mercaptan comprise about half the TRS compounds. 

emissions are 9,500 ppm from the digester system and 6700 ppm 

from the mu1 tiple-effect evaporator system.z4 

is only effective in controlling hydrogen sulfide and methyl mercaptan, 

alkaline scrubber efficiencies are roughly only 50 percent. 

TRS emissions from a scrubber are calculated to be about 0.63 g/kg ADP 

(0.59 g/kg ADP from digester system and 0.04 g/kg ADP from multipleeffect evaporator system1 or abut-7500 ppm. 

The composition of noncondensable 

23 

Uncon troll ed 

Since caustic scrubbing 

6.i.3 Lime Kiln 

TRS emissions, principally hydrogen sulfide, can originate from 

two areas in the lime kiln installation, the lime kiln proper and a 

scrubber that serves as the particulate control device. 

from the lime kiln installation are controlled by maintaining proper 

process conditions. 

in an industry (National Council of the Pulp and Paper Industry for 

Air and Stream Improvement) study 25include the temperature at the 

TRS emissions 

The most important parameters that were identified 

6-1 1 
cold end (point of exhaust discharge) of the kiln, the oxygen 

content of the gases leaving the kiln, the sulfide content of the 

lime mud fed to the kiln, and the pH and sulfide content of the 

water used in a particulate scrubber. 

used as the scrubbing medium, tke exhaust gases could strip out the 

dissolved TRS and increase the TRS emissions from the lime kiln 

installation. 

can reduce the TRS emissions from a lime kiln. 

If contaminated condensate is 

Scrubbing the exhaust gases with a caustic solution 

26 

The amount of retrofitting necessary to achieve proper process 

conditions depends on the design of the existing kiln installation. 

If the existing kiln does not achieve sufficient oxygen levels, 

increased fan capacity or changes to the scrubber system may be 

necessary to increase the air flow through the kiln. Molecular 

oxygen can also be used to replace a portion of the combustion air 

to increase oxygen levels. Additional lime mud washing capacity may 

also be necessary to reduce the sulfide content of the mud and 

thereby reduce TRS emissions. This may require replacement of 

existing centrifuges with more efficient vacuum drum fi 1 ters, and 

the addition of another mud washing stage. 

presently using condensate that contains dissolved reduced sulfur 

compounds for a scrubhi ng medium would have to either instal 1 a 

condensate stripper to remove the dissolved TRS prior to the scruhber 

or replace the condensate with fresh water. 

* 

Furthermore, a mill 

TRS emissions from existing lime kilns range from about 0.01 to 

2.0 g/kg ADP (4 to 840 ppml, depending on the degree of control, with 

6-1 2 
an average of about 0.4 g/kg ADP (168 ppm) . 27 EPA tests (conducted 

for NSPS development) on txo lime kilns indicate that lime kiln TRS 

emissions can be reduced to below 20 ppm (12-hour averaqe) using process controls. 

Another lime kilr, using caustic scrubbing in addition to process 

control is capable, based on EPA results, of TRS emissions helow 8 

ppm (12-hour average). When tested by EPA, all three lime kilns were burning 

non-condensable gases from the digester system and mu1 tiple-effect 

evaporator system. 

It appears that existing lime kilns can be retrofitted to also 

achieve low TRS emissions. 

installations have reportedly heen reduced from over 100 ppm to less 

than 20 ppm by modifying the lime mud washing systems and making 

adjustments in the process operation. 28 

TRS emissions from two existing lime kiln 

However, the TRS levels 

to which existing kilns can fie retrofitted depends on the load at 

which the kiln is normally operated. 

sufficiently over design capacity, it may be very d i f f i c u l t t o obtain 

the oxygen levels necessary for low TRS emissions [about 20 ppm). 

Discussions with the kraft i,ndustry indicate that TRS emissions from 

these lime kilns can be reduced, however, to ahout 40 ppm. 

If the kiln is operated 

6.1.4 Brown Stock Masher System 

Nearly all existing kraft mills vent the hr0w.n stock washing 

system gases directly to the atmosphere without control. 

least three mills in the United States and Candda, and one 

in Sweden, utilize the gases as combustion air in a recovery furnace. 

However, at 

The furnace systems handling these gases are newer furnace systems 

6-1 3 
which were designed to burn the washer gases. 

(not designed for burning these gases) has yet been used to incinerate the 

washer gases. 

No existing recovery furnace 

As discussed in section 6.1.2 the residual TRS after incineration is 

very low, less than 5 ppm (0.01 g/kg ADP). Since the gas volume from the 

washer drums is larqe, about 112 m /Mq (150 CFWJTPD), the most likely 

equipment for combustion is a recovery furnace or power boiler. 

due to their large volume, would have to supplement the recoverv furnace's 

combustion air requirements. Even if the washers were enclosed with tiaht 

3 29 

The oases, 

hoods, the gas volume would be too larae to burn in a lime kiln. The 

actyal gas volume handled at one mil 1 is 75 m3/Mg (100 CFMITPD) , The 

volume that would need to be handled at other existing mills can be h 

or lower depending upon tightness of hooding and degree of condensing 

gas 

qher 

The vent gases from the filtrate tank are considerably smaller in 

volume, about 4.5 m3/Mg (6 CFM/TPD).30 This stream is sufficiently small 

for combustion in a lime kiln, or blended with the hood vent gas and 

burned in a recovery furnace. 

Incineration of the washer gases in a recovery furnace will not 

affect furnace operation provided the moisture content of the qases 

is not too c~reat.~' 

sulfur emissions and produce unsafe operating conditions. 

(furnace) temperature decreases almost 1 inearly with increased content 

of vaporized water in the combustion air because of sensible heat 

losses. With decreased bed temperatures, SO2 emissions increase at a 

rapid rate and reduced sulfur compounds become increasinqly difficult 

High moisture content can increase aaseous 

Red 

6-14 
to control .32 

extremely dangerous conditions such as smelt-water explosions. 

Water entrained in the combustion qases can create 

One furnace manufacturer recommends that the washer gases be 

incinerated only in the secondary or tertiary air zones of the furnace. 

This would keep the moist washer gases away from the smelt bed. 

the gases only in the secondary or tertiary zones may affect the flexibility 

of the recovery furnace, 

Burning 

however, since the operator would not have the 

33 ability to vary the air flow rate to each zone. 

High moisture content would result in an increase in gas flow and 

reduce the capacity of the recovery furnace. 

An alternative to incineration of brown stock washer gases is 

chemical scrubbing. 

mentioned, is only effective in controlling hydrogen sulfide and methyl 

White 1 iquor (caustic) scrubbing, as previously 

mercaptan. 

system are principally dimethyl sulfide and dimethyl disulfide.34 A 

more effective system is reportedly a chlorination-caustic scrubbinq 

system. 

However, the TRS emissions from a brown stock washer 

In this system, the chlorine absorbs and oxidizes the dimethyl 

sulfide and dimethyl disulfide.35 This technique was installed at one 

mlll in February 1976 and tests conducted at that time demonstrated TRS 

emissions of less than 5 p~m.~~ Another technique is chlori,ne 9as injection. 

This technique is used at one mill and tests conducted demonstrated TRS 

emissions of less than 5 ppm and a control efficiency of 80 percent. 37 

6.1.5 Black Liquor Oxidation System, 

The vent gases from nearly all existinq black liquor oxidation (BLO) 

systems are emitted directly to the atmosphere without control. 

6-1 5 
One control technique is incineration. Incineration has proved 

highly effective in controlling similar streams in some mills, for 

example, the vent gases from pulp washing systems, the noncondensable 

gases from digesters and mu1 tiple-effect evaporators , and vent qases from 

condensate strippers. 

the recovery furnace or power boiler is most likely, since the BLO gas 

volume is usually too large to be handled by an existing kiln. 

would result in no significant fuel penalty. 

Similar to the pulp washing system, incineration in 

This 

Because of the high moisture content of the RLO gases, it would be 

necessary to use condensers to reduce the moisture content before 

burning, especially if the moist washer gases are burned in the same 

furnace. Incineration of these moist qases in the furnace would probab1.y 

cause increased corrosion problems in the forced-draft fan ductwork and 

the forced-draft fan itself. This would probably necessitate the replacement of this equipment with corrosion-resistant equipment. 

forced-draft fan may be necessary to handle the increased mass flow due 

to the high moisture content of the gases, even after usinq condensers. 

The recovery furnace operation should not be adversely affected by 

A larqer 

38 

burning the BLO gases, even in combination with the washer gases, 

provided the moisture content is sufficiently reduced and the qases are 

burned high in the f~rnace.~’ Since the BLO gases are deficient in oxygen, 

one furnace manufacturer suggests burning them in the sec0ndar.y or 

tertiary air zone but states that the gases should still contain 

sufficient oxygen to preclude adversely affecting the furnace operation. 

6-1 6 
As mentioned in Section 6.1.4, the operational flexibility of the furnace is 

reduced because a portion (BLO gases and washer gases) of the total combustion 

secondary and tertiary air zones and 

when air in this zone is needed to 

air must always be introduced into the 

cannot be used in the primary air zone 

adjust furnace operation. 

Emissions will be reduced to low 

burned. Since these gases contain the 

evels if oxidation vent qases are 

same TRS compounds present in the 

digester and mu1 tiple-effect evaporator off-qases which EPA tested after 

incineration, TRS combustion residuals of the BLO vent qas will be less than 

A second control technique is the use of molecular oxygen in oxidation 

systems instead of air. At least two mills in the United States now oxidize 

black liquor by pumping oxygen directly into the black liquor lines. There 

are no vent gases from this closed system. The economic feasibility of such 

a system depends largely on the price and availability of oxygen. 

Another technique is chlorine gas injection. This technique is used at 

one mill on the vent gases from primary oxidation system. Tests conducted 

demonstrated TRS emissions of less than 5 ppm and a control efficiency of 

40 95 percent. 

6.1.6 Smelt Dissolving Tank 

Smelt dissolving tank TRS emissions are governed by process conditions; that is; the presence of reduced sulfur compounds either in the 

smelt or the water. 

choice of water in the smelt dissolving tank or the particulate control 

device. 

The principal control option available is the 

Clean water, low in dissolved sulfides, is preferable, although 

6-1 7 
low emissions have been reported with nearly all process streams. a4 

If TRS emissions are hiqh and no particulate control device (scrubber) 

is used, a wet scrubber (e.q., packed tower) can be used to control the 

TRS emissions. 

emissions. One mill reportedly reduced TRS emissions over 95 percent 

This scrubber would also result in controlling particulate 

from a level of about 0.19 g/kg of black liquor solids (BLS) (0.56 lb/T ADP) 

when a packed scrubber tower was installed. 42 . 

TRS emissions from smelt dissolving tanks are normally low and average 

about 0.007 g/:.g BLS (0.02 lb/T ADP).43 EPA tests on two smelt dissolving 

tanks indicate TRS emissions below 0.0084 g/kg BLS (8 ppm). 

These levels can be achieved on both new and existing smelt tanks. 

Both these smelt tanks have wet scrubbers for control 1 ing particulates. 

Weak wash liquor was used as the scrubbing medium in both scrubbers. 

6.1.7 Condensate Stripping System 

In at least four United States mills, dissolved sulfides and other 

vol ati 1 e compounds are stripped from the di ges ter and evaporator condensates prior to discharge to treatment ponds. One mill, which uses steam 

as the stripping medium, discharges the gases from the stripper column 

to a lime kiln. Two mills use air as the stripping medium. One of these 

incineratesthe stripper gases in a separate incinerator, while the other 

incinerates the gases in the recovery furnace. One mil 1 , which uses steam, 

is presently scrubbing the stripper gases with white liquor, but this 

technique is not as effective as incineration. 44 

As mentioned in Section 6.1.2, incineration has proven to reduce 

~ TRS levels from digester and multiple-effect evaporator systems to less 

than 5 ppm. Since the vent gas from condensate strippers contains the 

6-18 
same TRS compounds present in the digester and multiple-effect 

evaporator aases, TRS emissions in the condensate stripper gases after 

incineration can be reduced to 5 ppm (0.01 g/kq ADP). 

6.2 SUMMARY OF RETROFIT MODELS 

Section 6.1.1 through Section 6.1.7 have examined the various 

control techniques that can be applied to each source of TRS emissions and 

have quantified the emission levels that can be achieved by applyinq 

these control 5. 

alternative control techniques will be discussed in Chapters 8 and 9, 

respectively. 

Simultaneously to the various TRS sources in the entire mill, various 

a1 ternati ve control systems (retrof i t model s 1 were devel oped. 

alternative systems chosen range from controllinq each TRS source to the 

best achievable level, to controllinq only the major TRS sources with 

techniques less effective than best available technology. The six 

retrofit models that use alternative control systems are listed in 

Table 6-2. These six control systems were selected because the 

differences between systems reflect major differences in the types 

and costs of retrofits that would be carried out at an existinq kraft 

mill. The economic and environmental impacts of these retrofit models 

will be analyzed in conjunction with the present controls already 

installed at each existing kraft pulp mill. 

are discussed bel ow. 

The economic and environmental impact of applying these 

In order to assess the impacts of applying controls 

The 

The six control systems 

Retrofit Model No. 1: All eight TRS sources are controlled to 

- the level of best available control technology. This s.ystem will 

6-19 
Table 6-2, POSSIBLE CONTROL SYSTEMS FOR 

EXISTING KRAFT PULP MILLS 

Source No, 1 

Control Systems/emission level (ppm) 

No. 2 No. 3 No. 4 No. 5 No. 6 

Recovery furnace Process control + 

Digester system Incineration/5 ppm 

Mu1 ti pl e-effect Inci neration/5 ppm 

BL0/5 ppm 

evaporator system 

Q, Lime kiln Process controls N + caustic scrub- I 

0 bing/8 ppm 

Brown stock Inci nerat i on/5ppm 

Black liquor Inci neration/5 ppm 

Smelt dissolving Frpzh wa+ar/P DM): 

I. 0084 g/kg BLS I 

Condensate Incineration/5 ppm 

washer system 

oxidation system 

tank 

stripper system 

Process control + 

Incineration/5 ppm 

Incineration/5 ppm 

BL0/5 ppm 

Process controls 

t caustic scrubbing/8 ppm 

No control 

No control 

Fresh water/8 ppm 

Incineration/5 ppm 

Process control + Process control t Process control + Process control + 

Incineration/5 ppm Incineration/5 ppm Incineration/5 ppm Incineration/5 ppm 

Incineration/5 ppm Incineration/5 ppm Incineration/5 ppm Incineration/5 ppm 

BL0/20 ppm* BL0/20 ppm* BL0/20 ppm* BL0/5 ppm 

Process controls Process controls/ Process controls/ Process controls/ 

bing/8 pDm 

No control No control No control No control 

+ caustic scrub 20 PPm 40 PPm 40 PP~ 

No control No control No control No control 

Fresh water/8 ppm Fresh water/8 ppm Fresh water/8 PPm Fresh water/8 PPm 

Incineration/5 ppm Incineration/5 ppm Incineration/5 ppm Incineration/5 ppm 

*The 20 ppm levels applies to old design furnaces; new design furnaces can achieve 5 ppm with application of the same control technology 

(two-stage BLO). 
result in the lowest TRS emissions from a kraft pulp mill and will 

require installation of a new furnace if the existinq furnace is 

relatively old and cannot achieve 5 ppm TRS. In most cases, this 

system will also requi 

and the improvement or 

order to achieve a TRS 

from the smelt dissolv 

e caustic addition to the existinq scrubber 

replacement of the lime mud washing facility in 

level of 8 ppm from the lime kiln. TRS emissions 

ng tank will be controlled by using fresh water 

in the tank and the particulate control device. Incineration will be 

used to control TRS emissions from the digester system, multiple-effect 

evaporator system, brown stock washer system, black liquor oxidation 

System and condensate stripping system. 

multiple-effect evaporators and condensate strippers will be incinerated 

in the lime kilns. 

for purposes of impact analysis are assumed to be burned in a separate 

incinerator since no existing recovery furnace has been modified to 

handle these gases. 

The gases from the digesters, 

The gases from the washers and oxidation system 

Retrofit Model No. 2: This control system is similar to 

Retrofit Model No. 1 except that the vent gases from the washer system 

and the BLO system are not incinerated. This system was chosen as 

a model because, based on the economic analysis performed for NSPS 

development, these two smaller TRS emission sources are less cost effective 

to control than the other sources. It is assumed that these two sources 

would be combined for treatment. 

related to the cost of controlling the other source because one 

incinerator would be installed to handle both gas streams. 

modifications made to an existing mill would generally be the same 

whether both or only one of these sources is controlled. 

The cost of controlling one source is 

Therefore, 

6-21 
Retrofit Model No. 3: This control system is similar to Retrofit 

Model No. 2 except that less effective control of the recovery furnace 

is allowed, resulting in a higher TRS level from this unit. This system 

was chosen because the higher TRS level (20 ppm) will allow mainly older 

recovery furnaces (mostly those built before 1965) to remain in operation. 

The 5 ppm level as required in Retrofit Models No. 1 and No. 2 would 

probably require these older furnaces to be replaced. 

of Models No. 1 and 2, if furnace replacement is necessary, will be 

substantially greater than that of Model No. 3. 

The cost impact 

Retrofit Hodel No. 4: This control system is similar to retrofit 

.Model No. 3 except that the lime kiln TRS level has been relaxed from 

8 to 20 PDm. 

level without using caustic scrubbing. 

This system would permit many kilns to achieve this 

The TRS emissions from the lime 

kiln would be controlled by process controls and require the lime mud 

washing facility to be improved or replaced. Caustic scrubbing would 

be a major expense if the caustic cannot be used in the pulping process 

or a wet scrubber is not already used for particulate control. 

Retrofit Model No. 5: This control system is similar to 

Retrofit Model No. 4 except that the lime kiln TRS level has been 

relaxed from 20 to 40 ppm. 

achieve the level without modifying the lime mud washing installation. 

TRS emissions from the lime kilns would be controlled by using process 

controls on the kiln itself. Modifications to the mud washing system 

are a major expense (see Chapter 8) in controlling TRS emissions from an 

existing kraft pulp mill. 

This system would permit many kilns to 

6-22 
Retrofit Model No. 6: This system is similar to Retrofit Model 

No. 5 except that all recovery furnaces are controlled to 5 ppm TRS 

rather than 20 ppm. 

on the impacts in relaxing controls on the lime kiln (Model No. 5) in 

comparison to relaxing controls on the recovery furnace (Model No. 3). 

This system was chosen to determine the differences 

6.3 INSTALLATION AND START-UP TIME 

The amount of time necessary to retrofit an existing kraft mill 

depends on what TRS sources are to be controlled and what technologies 

are to be used. 

ments to implement a given control technology can vary widely depending 

vpon such factors as space limitations, weather conditions, lack of 

available utilities, delays in equipment delivery, and time required to 

devel op engineering data. 

It should also be pointed out that actual time requireTable 6-3 presents estimates of the normal length of time required 

to retrofit the various sources in order to bring them into compliance. 

Table 6-3 shows that the time necessary for initial design and approval 

can vary from 6 months to 3 years, depending on the source and the 

complexity of retrofitting that source. This time period includes: 

a. Engineering design of the overall project; 

b. Project fund approval ; 

c. Control agency approval ; 

d. Order placement. 

Table 6-3 also presents estimates of the amount of time required 

for installation of the necessary equipment. This time is for the 

6-23 
Table 6-3. DESIGN AND INSTALLATION TIMES* 

. 

Design and 

approval** Instal lation*** 

TRS source (months ) (months ) 

Recovery furnace 18-36 12-36 

Digester system 6 18 

Mu1 tiple-effect 

evaporator sys tem 

6 18 

Lime kiln 6-24 24 

Brown stock 

was her sys tem 

Black liquor 

oxi da ti on system 

Smelt dissolving 

tank 

Condensate stripping 

system 

6-24 12-1 5 

6 12 

6 18 

6 18 

qased on discussions with various companies and manufacturers. The actual times 

of aooroval and installation may over-lar, to some extent. 

**This time period includes: engineering design of the overall project; project 

fund approval ; control agency approval ; and order pl acement. 

***From the order date to start-up (start-up excldded). 

6-24 
period from the order date to start-up (start-up excluded). 

time varies from about one year for installing black liquor oxidation system 

to three years for installing a new recovery furnace. 

This installation 

6-25 
REFERENCES FOR CHAPTER 6 

1. 

Furnace and Direct Contact Evaporator, NCASI Technical Bulletin No. 44, 

December 1969. 

Factors Affecting Reduced Sulfur Emissions from the Kraft Recovery 

2. 

Compounds from a Kraft Recovery Furnace, Thoen, G. N. , De Haas G. G. 

Tallent, R. G., and Davis, A. S., TAPPI, 51(8):329-333, August 1968. 

3. Op. ci t. , Reference 1, page 28. 

The Effect of Combustion Variables on the Release of Odorous Sulfur 

4. Op. ci t., Reference 1 , page 31. 

5. Meeting Report - Babcock & Wilcox Company and EPA, Durham, NC, 

May 1, 1975. 

6. Op. cit., Reference 4. 

7. Op. cit., Reference 5. 

8. Op. cit., Reference 5. 

9. Improved Air Pollution Control for a Kraft Recovery Boiler: 

Recovery Boiler No. 3, Henning, K., Anderson, W. , and Ryan, 3. , EPA 

Report No. 650/2-74-071-a, August 1974. 

Modified 

10. 

Industry, NCAS; Technical Bulletin No. 39, December 1968. 

11. 

Survey of Current Black Liquor Oxidatlon Practices in the Kraft 

Op. cit., Reference 10, Table 6. 

12. Standards Support and Environmental Impact Document , Vol ume 1 : 

Proposed Standards of Performance for Kraft Pulp Mills, Environmental 

Protection Agency , September 1976. 

13. Letter from J. W. Kisner of Babcock & Wilcox Company to James 

Eddinger of EPA, dated May 27, 1975. 

14. 

NAPCTAC meeting in Raleigh, North Carolina, on March 3, 1977. 

Presentation given by Julius Gommi of Combustion Engineering at the 

6-26 

E 
15. Op. cit., Reference 13. 

16. 

Ecology and the Oregon Department of Envi ronmental qual i ty . 

17. 

Container Corporation of America, March 9, 1977. 

18. Op. cit,, Reference 17, page 2. 

Ecology and the Oregon Department of Environmental Qual i ty. 

19. Considerations in the Design for TRS and Particulate Recovery from 

Effluents of Kraft Recovery Furnaces, Teller, A. J., and Amberg, H. R., 

Preprint, TAPPI Environmental Conference, May 1975. 

20. 

Kraft Industry, NCASI Technical Bulletin No. 34, November 1967. 

Monthly Reports obtained from the Washington Department of 

A Report on the Study of TRS Emissions from a NSSC-Kraft Recovery Boiler, 

Current Practices in Thermal Oxidation of Noncondensable Gases in the 

21. 

EPA-450/1-73-002, September 1973. 

Bulleton No. 69, February 1974.) 

22. 

Off-Gases, EPA Test Report No. 73-KPM-lA, 1973. 

23. 

24. 

25. 

Emissions of Reduced Sulfur Through Control of Kiln and Scrubber Operating 

Variables, NCASI Special Report No. 70-71, January 1971. 

26. 

Adams, A. B., TAPPI, September 1974. 

27. Op. cit. , Reference 21, Table A-5. 

Atmospheric Emissions from the Pulp and Paper Manufacturing Industry, 

(Also published by NCASI as Technical 

Malodorous Reduced Sulfur Emissions from Incineration of Noncondensable 

Op. ci t., Reference 21 , Tables 3, 5, and 7. 

Op. cit., Reference 21, Tables 3, 5, and 7. 

Suggested Procedures for the Conduct of Lime Kiln Studies to Define 

Kraft Odor Control at Mead Papers, Ayers, K. C. , Clutter, L. W., and 

- 28. Trip Report on Visit to the Champion International Mill in Pasadena, 

Texas, on April 4, 1975. 

6-27 
29. Factors Affecting Emission of Odorous Reduced Sulfur Compounds ----- II_ ----_- ll---ll_-- 

from Miscellaneous Kraft Process Sources, WAS1 Technical Bulletin 

No. 60, March 1972. 

30. Op. cit., Reference 29. 

31. Op. cit., Reference 13. 

,32. Letter from S. T. Potterton of Babcock & Wilcox Company to James 

Eddinger of EPA, dated July 23, 1974. 

33. Op. cit. , Reference 5. 

34. Op. ci t. , Reference 29, page 6. 

35. Letter from H. M. Patterson of Oregon Department of Environmental 

Quality to James Eddinger of EPA, dated April 4, 1975; and letter from 

L. A. Broeren of Crown Zellerbach Corporation to Doug Ober of Oregon 

Department of Environmental Qual i ty , dated January 10 , 1975. 

36. 

of Environmental Quality and James Eddinger of EPA on December 6, 1976. 

37. 

Control District. 

38. Letter from Russell Blosser of NCASI to Paul Boys of EPA dated 

November 17, 1972. 

39. Op. cit., Reference 19. 

40. Op. cit., keference 37. 

Telephone conversation between Chuck C1 inton of Oregon Department 

Monthly Reports obtained from the Humboldt County Air Pollution 

41. Op. cit. , Reference 3, Table 25. 

42. 

Company and James Eddinger of EPA on July 19, 1973. 

43. Op. cit. , Reference 47. 

Telephone conversation between Richard Labrecque of S. D. Warren 

- 44. Private communication between Arthur Plummer of Chesapeake Corporation and James Eddinger of EP.l on February 13, 1975. 

6-28 
CHAPTER 7. EMISSION PIONIJORING AND COMPLIANCE 

TESTING TECHNIQUES AUD COSTS 

This chapter discusses the various monitoring and compliance testing 

methods that have or could be used in the kraft pulp industry, and also 

discusses the rationale leading to the selection of the reference test 

method used for the TRS source tests conducted during the SPNSS development 

program. 

7.1 EMISSION MEASUREMENT TECHNIQUES 

7.1.1 Emission Monitoring 

Performance specifications for oxygen continuous monitors have a1 ready 

been published in 40 CFR, Part 60, Appendix By Performance Specification Three, 

but it has not been demonstrated that these monitors will perform in the same 

manner when used at a kraft pulp mill. 

to believe that they will not be able to meet these requirements. 

commercially available instruments are capable of meeting the performance 

specifications. 

range of $9,000 to $11,000. 

There is, however, no technical reason 

A number of 

The cost of one of these instruments, installed, is in the 

Equipment is also commercially available for temperature monitoring. 

can be accomplished using a thermocouple, electronic cold junction, and a 

millivolt strip-chart recorder. 

less than $2,000. 

This 

A system such as this could be purchased for 

Instrumentation is also available for continuously monitorina 

the pressure loss of the gas stream through the scrubber and for monitoring the 

scrubbing liquid supply pressure to the scrubber. 

7-1 
- 

At present, there are several types of instruments that have been used 

to successfully measure TRS on a short-term basis. However, some questions 

remain about their reliability for data gathering on a continuous basis. 

GC technique described in Method 16 was not designed to be used as a continuous 

monitor and its suitability for this purpose has not yet been evaluated. 

There are other systems which have been used on a long-term basis but necessary 

maintenance and quality control procedures to insure that these monitors are 

The 

operating properly are still being developed, 

cooperation with the National Council for Air and Stream Improvement to evaluate 

Work is presently underway in 

a number of different types of systems for their suitability as continuous 

monitors. 

for TRS monitors. 

7.1.2 Compliance Testing 

7.1.2.1 TRS Compounds - The need for an effective test method for measurement 

of reduced sulfur emissions from stationary sources resulted from a new source 

performance standard (NSPS) program to establish performance standards for a 

variety of kraft mill unit processes with respect to malodorous emissions. 

U1 timately, this should result in pub1 ished performance specifications 

As 

with previous NSPS programs, test methodology was needed to gather: 

data which would demonstrate emission limitations attainable through the use 

(a) accurate 

of best available emission control systems; and (b) enough sampling and analytical 

data such that a reference method for performance testing could be prescribed. 

At the inception of the NSPS kraft mill program in January 1972, a survey 

was made to evaluate existing test methods for potential use. This survey 

included a review of the literature, contact with mill personnel, and review of 

previous research and evaluation of analytical techniques by the Environmental 

Protection Agency (EPA). Since the degree to which methods are available for 

field use in odor measurements is directly related to the complexity of the 

odorant mixture to be measured, it was fortunate that the nature of emissions 

7-2 
from kraft pulping operations had been well-defined. 

primarily of sulfur dioxide (SO2) and four reduced sulfur compounds 

hydrogen sulfide (H2S) , methyl mercaptan (CH3SH), dimethyl sulfide (DMS) , 

and dimethyl disulfide (DMDS). These compounds are highly reactive, 

particularly the H2S-S02 mixture which may form elemental sulfur, and are 

present in low concentrations in well-controlled sources. In addition, the 

sources of these emissions (recovery furnaces, lime kilns , smelt dissolving 

tanks , digesters, mu1 tiple-effect evaporators , washer systems , oxidation 

Emissions consist 

- 

systems, and condensate strippers) are characterized by high temperatures and 

moist, particulate-laden effluent streams. 

After careful consideration, it was determined that an additive total 

reduced sulfur (TRS) standard, reflecting all sulfur compounds present minus 

SO , was desired. 

tions, a field method which could measure reduced sulfur compounds, either indiConsidering this and the previously mentioned source condi- 2 

vidual ly or col 1 ectively , was sought. 

7.1.2.1.1 Methods surveyed - A review of the literature revealed that 

analytical methods fell into four main categories: colorimetry, direct 

spectrophotometry, coulometry, and gas chromatography. Although most of the 

methods surveyed were developed for measurement of ambient concentrations, this 

did not preclude their possible application to the measurement of stack emissions. 

Colorimetry - A sample is bubbled through a solution which 

selectively absorbs the component or components desired. 

is then reacted with specific reagent to form a characteristic color which is 

measured spectrophotometrically. 

The absorbed compound 

An example of a colorimetric method is the methylene blue 

method which involves the absorption of TRS compounds in an alkaline suspension 

7-3 
of cadmium hydroxide to form a cadmium sulfide precipitate. 

is then reacted with a strongly acidic solution of N, N, dimethyl-p-phenylenediamine and ferric chloride to give methylene blue, which is measured spectrophotometrically. Automated sampling and analytical trains using sequen ial 

techniques are available for this procedure. 

sampling applications include variable collection efficiency, range lim tations, 

and interferences from oxidants. 

The precipitate 

Inherent deficiencies for stack 

Another colorimetric method is the use of paper tape samplers 

impregnated with either lead acetate or cadmium hydroxide. 

react specifically with H2S and the resultant colored compound can be measured 

djrectly with a densitometer. 

TRS compounds unless they were all reduced quantitatively to H2S. In addition, 

the range is limited and the method suffers from light sensitivity, fading, the 

necessity for precise humidity control, and variability in tape response. 

These compounds 

Tape samplers would not be appropriate for all 

Spectrophotometry - The use of infrared and mass spectrophotometry and other sophisticated spectroscopic methods for analysis of 

individual odorants is well established. However, these methods were considered 

expensive, time consuming, and not suitable for routine field applications. 

One promising method in this area was split-beam ultraviolet 

spectrophotometry, which utilizes the strong absorption of ultraviolet radiation 

at 282 nm by SO2. 

and split into two streams. 

furnace where sulfur constituents are oxidized to SO2 and then through an 

optical cell where its absorbance is measured. 

a dummy furnace and then into a reference optical cell. The difference in 

abosrbance values between the two cells is a measure of the non-S02 sulfur 

In this method, the gas sample is mixed with air, filtered, 

One stream passes through a catalytic oxidation 

The second stream passes through 

7-4 
constituents in the sample stream. 

in the range of 10 to 2500 ppm. 

The system is capable of S02/TRS concentrations 

Since well-controlled kraft mill sources fall 

below the minimum range of 10 ppm, this method was considered not applicable. 

Coulometry - Coulometric titration is based on the principle 

of electrolytically generating a selected titrant in a titration cell. The 

titrant may be a free halogen (bromine or iodine) in aqueous solution as an 

oxidizing agent, or a metal ion (silver), as a reducing agent. 

current required to generate the titrant, as it is consumed, is a linear 

measure of the concentration of reactive compounds in the gas sample. 

The electrolytic 

Gas Chromatography - This system is based on the ability of 

the gas chromatographic col umns to separate individual sul fur compounds, which 

are then determined individually by various analytical techniques. The most 

sensitive determination is the flame photometric detector (FPD). 

involves measurement of light emitted from the excited SO2 species formed when 

a sulfur compound is burned in a hydrogen-rich flame. 

This technique 

7.1.2.1.2 Methods used for data gathering - 

Analytical Techniques - Based on the survey, the GC/FPD 

technique was considered to be the most promising and was selected for field 

evaluation. At several of the plants, the coulometric titrator was also tried 

since this instrument was widely used by the industry at the time. 

Sample Collection - Considering the sulfur compound reactivity, 

high moisture, and presence of particulate matter, EPA developed a special 

sample handling system. 

steel sheath with inlet ports perpendicular to the stack wall. 

It utilizes a sampling probe enclosed in a stainless 

A deflector 

7-5 
shield is fixed on the underside to deflect the heavier particles while the 

proble is packed with glass wool to trap finer particles. Teflon tubing 

heated to 250°F is used to carry the sample from the probe to a dilution 

system where the sample is routinely diluted 1:9 with clean dry air. 

heated sample line prevents condensation and teflon does not react with sulfur 

compounds. After the sample is diluted in a heated dilution box, its moisture 

content is reduced so that the dew point is below ambient temperature, preventing 

condensation and sample 1 oss during analysis. 

The 

Calibration of Instruments - For delivery to and calibration 

of analytical instruments, a special system containing premeation tubes with 

appropriate concentrations of SO2, H2S, DMS, DMDS, and CH3SH were installed 

into the sampling and analytical system. These gas permeation tube standards 

were developed by EPA personnel specifically for use with GC systems. 

Field Evaluation - Since 1972, EPA has used the sample 

delivery system, dilution system, calibration system, and the GC/FPD methods 

at a number of kraft mills. Two separate GC/FPD systems were employed to 

facilitate the rapid analysis of both high and low molecular weight sulfur 

compounds. 

simultaneously resolved DMDS and other high molecular weight homologs. 

ensure reliabi 1 i ty 7f the data , the GC/FPD systems were frequently cal i brated 

One system resolved H2S, SO2, CH3SH, and DMS, while the other 

To 

with standards of each of the sulfur compounds. 

Field experience has shown that the GC/FPD method is the 

most reliable, sensitive, and precise for determination of TRS. 

a1 so been substantiated via verbal communications with industry experts. 

This has 

There, may, however, be some loss of precision in using this method on 

sources having high levels of SO2 in compari ;on LO the level of TRS. 

Further developmental work is underway to eliminate this problem and the 

necessary changes will be made in Method 16 as soon as the work is completed. 

7-6 
Conversely, at six of these kraft mills; two different 

coulometric instruments have yielded poor results, possibly due to the low 

concentrations encountered and operationai problems. This instrument is 

unacceptable for compliance testing. 

7.1.2.1.1 Compliance method - As the result of field experience of 

testing TRS compounds at kraft mills, Method 16 was prepared for determining 

compliance with new source performance standards. This method requires 

use of a GC/FPD system using the same measuring principle as used for 

the data gathering y-ocess. 

required dilution system, calibration techniques, and instrumentation that 

was considered necessary to insure accuracy, precision, and reliability 

Design specifications for the 

are specified. 

7-7 

8. COST ANALYSIS OF ALTERNATIVE EMISSION CONTROL SYSTEMS 

8.1 Introduction 

The purpose of this chapter is to develop estimates of retrofit costs 

for alternative emission control systems for reduction of total reduced 

sulfur (TRS) emissions at existing kraft pulp mills. 

costs will be developed for a1 ternative controls on each affected facility 

on three sizes of kraft pulp mills: 500, 1000, and 1500 ton per day mills. 

Following this, aggregate costs will be presented for six a1 ternative emission 

control systems on a 1000 TPD kraft pulp mill. 

analysis for estimating industry-wide costs will be presented. 

Capital and annualized 

Finally, a summary of an 

The determination of incremental costs for the various control alternatives over state regulatdons for kraft mill sources is a critical 

element in this analysis. 

which vary widely in their effectiveness of reducing TRS emissions. 

variability in regulations from state to state has been taken into account 

in the determination of total industry costs. 

Some 28 states with kraft mills have regulations 

The 

Throughout this chapter the terms capital cost and annualized cost 

are used; therefore, a brief definition is in order. 

includes all the items necessary to design, purchase, and retrofit either 

a control device or process equipment necessary to achieve the emission 

reduction. The capital cost includes the purchase of all factory assembled 

equipment, such as a recovery furnace boiler, black liquor oxidation system 

components, incinerator, and so forth; ancillary items, such as fans, instrumentation, pumps; equipment installation cost including demolition, site 

clearance, piping, wiring, and the cost of engineering, construction 

overhead, and contingencies. Capital costs are reported in third quarter 

The capital cost 

8- 1 
1976 dollars. The annualized cost of a retrofit project, whether it be a 

control device or replacement of process equipment, is a measure of what 

it costs the company to own and operate that system. The annualized cost 

includes direct operating costs such as labor, uti1 ities and maintenance; 

and capital related charges such as depreciation, interest, administrative 

overhead , property taxes , and insurance. The actual costs experienced by 

individual mills may vary considerably and often are difficult to collect. 

Nevertheless, attempts must be made to determine reasonable estimates of 

these costs. The following values were chosen as typical and should provide a reasonable estimate of the annualized costs of the retrofit control 

requirements. Operating labor is charged at a rate of $6 per hour with 

supervision at $8 per hour. Electricity is assumed to cost 2.5 cents per 

kilowatt-hour. Fuel costs are assessed at $2.00 per million BTU, For 

purposes of estimating annualized costs, 328.5 operating days per year 

were assumed. 

Recovery furnaces and 1 ime kil ns that would constitute replacements 

necessary to achieve TRS reduction are not allocated any charges for maintenance and repair. The reason for this is that such maintenance costs 

incurred for rep1 -cement would be offset by maintenance charges foregone 

in scrapping the old equipment. 

For gas collection and piping systems, including incinerators, maintenance costs are assessed at 2 percent of capital jnwestment. For 

black liquor oxidation systems and oxygen plants, a charge of 4 percent of 

capital investment is expensed. 

8-2 
i 

Capital charges have been calculated on the basis of 100 percent 

debt financing and recovery of capital by uniform periodic payments 

(capital recovery factor). Rate of interest for institutional lending 

is assumed to be 10 percent. The economic life assumed for all equipment 

is 15 years. 

percent. Administrative overhead costs involving records keeping, 

monitoring, etc. are also assessed at a rate of 2 percent. 

8.2 Methodology 

Property taxes and insurance are assessed at a rate of 2 

The affected facilities and control systems were previously discussed 

in Chapter 6. 

emission reductions, as outlined in Table 6-2, are summarized in Table 8-1 

The retrofit control techniques that can achieve the necessary 

for each affected facility and control system. These control techniques 

were based on certain assumptions, which reflect the content of information 

available for estimating retrofit costs. These assumptions will be discussed in detail in the following subsections for each affected facility. 

The cost information on retrofit controls for recovery furnaces nresented 

in this chapter applies to cross-recovery furnaces as well as straight kraft 

recovery systems. However, there is one precaution that should be noted. 

T!?e application of the control techniques for straight kraft recovery furnaces 

as discussed here and in Chapter 6 will not necessarily result in the same 

achievable emission levels for cross-recovery furnaces as reported in this 

chapter. 

For cost estimating purposes, a list of mill characteristics was 

compiled for each kraft pulp mill in the United States. 

com?iled includes Kraft production capacity; number, capacity, manufacturer, 

basis design (direct or indirect contact) and year of manufacture of the 

recovery furnace; the number and production rate for lime kilns; the number, 

The information 

8- 3 
SOURCE 

Recovery Furnace 

Table 8-1. SUMMARY OF RETROFIT CONTROL TECHNIQUES FOR ALTERNATIVE CONTROL SYSTEMS ON EXISTIilG KRAFT MILLS 

CONTROL SYSTEMS 

1 2 3 4 5 

a) Replace Furnaces Same as a) Replace Furnaces Same as Same as 

b) Add 2nd Stage Black 

>lo yrs. of age 1 '20 yrs. of age 3 3 

b) Add 2nd Stage Black 

Liquor Oxidation liquor oxidation for 

(IncludiRg furnaces all other furnaces. 

<lo yrs. of age). Also A1 so improve furnace 

inprove furnace air air distribution. 

distribution 

Digester System Incineration Incineration Incineration Incineration Incineration 

Mu1 tiple Effect Evaporators Incineration Inci nera t i on Inci nerat ion Incinera t i on Incineration 

Lime Kiln 

Y 

P 

a) Increase Lime Mud Same as Same as Washing Capacity 1 1 

b) Increase fan cap. 

c) ma caustic to 

& Monitor Oxygen 

and temp. (kiln) 

kiln scrubber 

a) Increase Lime .a) Increase Fan 

Mud Washing Cap. & Monitor 

Capacity Oxygen and 

b) Increase Fan temp. (Kiln) Cap. & Monitor 

oxygen p1 temp(ki1n) 

Brown Stock Washer System Incineration No Control No Control No Control No Control 

Black Liquor Oxidation Mol ecul ar Oxygen No Control No Control 

Smelt Dissolving Tank Substitute fresh Same as Same as 

Condensate Stripping Incineration Incinerat ion Inc i nerat i on 

System 

System Vents 

water for condensate 1 1 

No Control No Control 

Same as Same as 1 1 

Inc inera t ion Incineration 

6 

Same as 1 

Incineratioil 

Incinerati or, 

Same as 

5 

'.No Control 

No Control 

Same as 

1 

Incinerati or-) 

:I 
I 

type, and TRS control s for mu1 tiple effect evaporators and digesters; 

and the number of brown stock washing systems and number of washing stages 

per system. and 

Lockwoods' directories and updated wherever possible from contacts with 

pulp and paper companies. 

Mill capacity and other data were compiled from Posts' 

The approach used to estimate retrofit control costs is as follows. 

The National Council for Air and Stream Improvement (NCASI) was called 

upon to provide EPA both the contacts within individual paper companies 

for sources of cost data and the technical parameters, or guidelines, (3) 

for estimating costs. 

personnel for estimating costs. The following 8 companies were selected 

and contacted to provide maximum coverage in terms of mills and capacity: 

These guidelines were also made available to industry 

(a) International Paper 

(6) Weyerhaeuser 

(c) Georgia Pacific 

(d) Westvaco 

(e) Boise Cascade 

(f) St. Regis 

(9) 

(h) Mead Corpora t i,on 

Western Kraft (Wil lamette Industries) 

Actual corporate data covering both costs and mill characteristics were 

provided for 42 mills by these companies. This coverage constitutes 35 

percent of the number of total mills and about 41 percent of total U.S. 

capacity. 

furnaces in the U.S.,were contacted to provide information on ages of 

existing furnaces, as well as the cost of new furnaces. In-house information was used to generate cost estimates, which were then used as a forum 

for discussion during visits with the corporate staff of the eight paper 

companies. The time for the data gathering phase was the second quarter 

of 1975. 

Two boiler manufacturers, who have built all the kraft recovery 

- 

8-5 
The data received from the paper companies were analyzed for regression 

The next step was to develop model 

500 tons per day, 1000 tons per 

These model plant costs in 

possibilities with mill characteristics. 

plant costs for the following model mills: 

day, and 1500 tons per day production capacity. 

combination with the information on mill characteristics and furnace age 

were used to estimate costs for the remaining 65 percent of the mills in 

the U.S. 

8.3 Costs for Affected Facilities 

8.3.1 Recovery Furnaces 

The major problem from the standpoint of TRS emission in existing 

kraft mills is associated with the burning of black liquor in direct 

contact recovery furnaces. 

(1) close monitoring and control of the process variables in the recovery 

furnace and, (2) oxidizing the black liquor to reduce the sulfides content 

The methods used to reduce these emissions are: 

before evaporation of the black liquor in the direct contact evaporator. 

Control of the process variables depends significantly upon the original 

design and configuration of the recovery furnace. 

critical factor in determining the extent of retrofit costs. 

Hence, furnace age is a 

Recovery furpaces , including both direct contact and indirect contact , 

of new design - as defined in ChaDter 6 - are capable of achievinq a 5 ppm 

level of TRS without any additional costs for process controls, as indicated 

in Chapter 6. 

as flexibility in air distribution and the membrane insulation between wall 

Many of those process controls discussed in Chapter 6, such 

tubes, are inherently designed in most furnaces constructed since 1965. 

with a direct contact furnace of the design just mentioned are assumed to 

incur costs only for a second stage of black liquor oxidation as the 

rqills 

8-6 
requirement for achieving a 5 ppm level of TRS from the total recovery 

furnace affected facility. Mil 1s with indirect contact furnaces are 

assumed to achieve the 5 ppm without any additional costs. 

indirect contact furnace design concept has been commercially available 

only since 1967. 

Note that the 

Recovery furnaces built prior to 1965 are assumed to be incapable of 

achieving a 5 ppm level of TRS despite any attempts to achieve the most 

efficient black liquor oxidation system. 

is related to the earlier design of the furnace itself, which was not conducive toward reduction of TRS to low levels. Therefore, the control 

strategy for a 5 ppm level would require the replacement of the recovery 

furnace, which constitutes the retrofit cost. For furnaces built 

between 1955 and 1965, the 20 ppm level is assumed to be achievable, according 

to NCASI guidelines and discussion in Chapter 6. The only costs incurred 

are those associated with adding a second stage of black liquor oxidation. 

For furnaces built prior to 1955, the retrofit costs assumed include replacement of the furnace plus a complete 2-stage black liquor oxidation for 

The key element in the assumption 

both the 5 ppm and the 20 ppm control 

with NCASI guide1 ines. 

Another important factor besides 

need for additional black 1 iquor burn 

levels. This assumpt 

age that would affect 

ng capacity. In part 

on is in accord 

costs is the 

cular, mills 

that have not added a recovery furnace since 1965 may be overloading furnaces with black liquor from a design standpoint. 

to high TRS emissions. 

1965 and appear to have underrated furnace capability, according to 

available data on mill characteristics, are assumed to add additional 

Such a practice leads 

Mills that have furnaces built between 1955 and 

8-7 
black liquor burning capacity in order to achieve the 20 ppm strategy. 

Therefore, such mills would have to purchase a new furnace in order to 

achieve the 20 ppm level. 

Additional guidelines were developed by NCASI to provide these companies technical parameters for black liquor oxidation as a complement to 

process controls in the recovery furnace toward achieving the 5 ppm and 

the 20 ppm levels. 

The guidelines used for estimating coSts of black liquor oxidation 

requirements are stated as follows. 

of best technology consists of: 

stage of oxidation, (6) retention time of five hours for both stages combined, (c) stand-by blower capacity, and (d) monitoring of both oxidizing 

air and liquor flow rates. The NCASI provided these guidelines to each 

company, which in turn was to assess its requirements relative to their 

existing oxidation system capabilities. 

The oxidation system representative 

(a) two-stage oxidation with at least one 

The costs presented in Table 8-2 for model plants were analytically 

derived from the results received for some 42 mills. 

furnaces in 17 mills, which management felt may be required, correlated 

reasonably well with mill size as a parameter. 

from various companies for oxidation requirements as to the condition of 

existing oxidation systems, sulfidity of black liquor, and level of experience acquired with development of highly efficient oxidation systems 

did not correlate well with mill size. This result occurred despite the 

specific guidelines set forth by NCASI to the managerial staff of the 8 

Cost data for recovery 

Conversely, data received 

- companies. A probable explanation is that the nature of mi71 operations 

and mil 1 lay-out vary widely, which affect costs significantly. 

8- 8 
Tab1 e 8-2. RETROFIT CONTROL COSTS FOR RECOVERY FURNACES 

I 

CD 

Mill Size, TPD 

Capital Costs ($) 

Annual ized Costs ($/Yr. ) 

Annualized Costs per Ton ($/T) 

~~ 

Mill Size. TPD 

500 1000 

600 , 000 1,000,000 

153,000 242 , 000 

0.93 0.74 

Capital Costs ($) 

Annualized Costs ($/Yr.) 

Annualized Costs per Ton ($/T) 

A. Furnace Replac 

500 

13,400,000 

2,270 , 000 

13.82 

men 0 1 t 

1000 

23 , 300,000 

4,000,000 

12.18 

1500 

32 , 200,000 

5,470,000 

11.09 

1500 

1,500 , 000 

360,000 

0.73 

(1) Control strategy required to achieve 5 ppm for mills whose furnaces were built prior to 1965. 

(2) Control strategy required to achieve 20 ppm for furnaces built since 1955. 

Costs 

i ncl ude secondary 61 ac k 1 i quor oxidation. 

assumed unable to achieve 20 ppm; require replacement. 

Pre-1955 furnaces are 
8.3.2 Digesters and Mu1 tiple Effect Evaporators 

The control technique for achieving a 5 ppn level is incineration of 

the noncondensi bl e TRS compounds emitted from various vents. 

of the retrofit project involves the collection of the noncondensibles and 

piping them to the incineration point, as well as necessary upgrading of 

The nature 

the blow heat recovery system associated with the digesters. 

incineration point is the lime kiln; however, in some situations, a separate 

incinerator may be used as the back-up for the lime kiln or as the regular 

control device. 

Normally, the 

Data gathered from the selected paper companies did not reveal any 

significant correlation of cost with mill size. The probable explanation 

of this are the number of digesters, their spatial arrangement, condition 

of blow heat recovery system, and type of gas holding system, 

weak correlation of costs with capacity estimates were made for model plants 

to represent three conditions: 

requirements only (low retrofit penalty]; (21 batch digesters with extensive 

piping , refurbished blow heat recovery, and separate incineration; (high 

retrofit penalty) and (3) continuous digesters. Mu1 tip1 e effect evaporator 

vents are assumed to be combined with the digester vents for all three cases. 

The costs for incineration are presented in Table 8-3. 

for electricity and fuel were developed from data by an engineering construction company. (5) 

noncondensible TRS emissions are based on use of a separate incinerator as 

a stand-by control device for 33 days, or ten percent of the time. 

Despite the 

(1 ) batch digesters with extensive piping 

Utility requirements 

Fuel consumption assumed in Table 8-3 for destruction of 

This 

- represents an assumed duration of downtime fc; the lime kiln for maintenance 

when the kiln becomes unavailable as a control device for incinerating TRS 

emissions. 

8-10 
Table 8-3. RETROFIT CONTROL COSTS FOR DIGESTERS AND MULTIPLE EFFECT EVAPORATORS 

Mill Size, TPD 

A. Batch Digesters - Low Retrofit Penal 

500 

Mill Size, TPD 

Capital Costs ($) 

Annualized Costs ($/Yr.) 

Annualized Costs per Ton ($/T) 

500 1000 

400,000 

96,000 

0.58 

Mill Size 

1000 

900 , 000 

210,000 

0.64 

500 1000 1500 

B. Batch Digesters - High Retrofit Pena 

I I 

03 Capital Costs ($) d 

d 

Annual ized Costs ($/Yr. ) 

Annualized Costs per Ton ($/T) 

900,000 

207 , 000 

1.26 

2,000,000 

452 , 000 

1.38 

1500 

1,600,000 

360,000 

0.73 

1500 

3 , 500,000 

773,000 

1.57 

Capital Costs ($) 

Annualized Costs ($/Yr.) 

Annualized Costs per Ton ($/T) 

300,000 

67 , 000 

0.41 

400,000 

96 , 000 

0.29 

500,000 

125,000 

0.25 

I 

(1) Includes provision for extensive piping only. 

(2) Includes blow heat recovery system, extensive piping , separate incinerator. 
8.3.3 Brown Stock Washers 

The control technique for achieving the 5 ppm level of TRS emissions 

from washer vents is incineration. 

either in the recovery furnace or a separate incinerator. 

The incineration may be carried out 

As pointed out 

in Chapter 6, incineration in an existing recovery furnace may restrict 

the operation of the recovery furnace. The gas flows from the washer 

system are too great for the lime kiln to incinerate. For some mills, a 

separate incinerator may be the only available control device to treat the 

washer vent gases. 

a 

tion requirements of 100 scfm/TPD, a parameter which is documented In 

Chapter 6. The basis for estimating hooding and ducting requirements 

was information provided from NCASI for actual retrofit situations. 

The capital costs for a separate incinerator were developed from data by 

the Industrial Gas Cleaning Institute(7) for an incinerator [with heat 

recovery) appl ication on an asphalt saturator plant. 

Preliminary EPA costs were developed in-house on the basis of ventila- 

(6) 

The prel iminary EPA 

costs were dissiminated to the selected group of paper companies for comment. 

The responses from these companies was assimilated into revision of the 

estimates, which are presented in Table 8-4. 

It must be pointed out that some unusual retrofit problems can occur 

at specific mills, where hooding brown stock washers may be constrained 

severely by space limitations. 

the washing building and reconstruction may be required. 

In such mills, demolition of portions of 

In other mills, 

- the washers may have to be replaced with semi-closed drum washers. For 

these situations, retrofit costs may be much higher than those estimates 

presented in Table 8-4. 

8-12 
Table 8-4. RETROFIT CONTROL COSTS FOR BROWN STOCK WASHERS 

Mill Size, TPD 500 1000 1500 

Capital Costs ($) 

Annualized Costs ($/Yr.) 

Annualized Costs per Ton ($/T) 

1,600,000 

900 , 000 

5.48 

2 , 500,000 

1,670,000 

5.08 

3,200,000 

2,400,000 

4.87 

Mill Size, TPD 

Capital Costs ($) 

Annualized Costs ($/Yr.) 

Annualized Costs Per Ton ($/T) 

B. Destruction in 

50 0 

900 , 000 

192,000 

1.17 

ecovery Furnace 

1000 

1,500,000 

326 , 000 

0.99 

1500 

1,900,000 

423,000 

0.86 
For separate incineration, a fuel penalty of 1.76 million BTU per 

ton pulp was used. The basis for this is 22 million BTU per hour for a 

30,000 scfm incinerator uti1 izing primary and secondary heat recovery. (8) 

Responses from the industry indicated that this fuel penalty is just 

slightly above the industry average. It should be pointed out that fuel 

requirements would be sensitive to ventilation rates of the washers, the 

degree of heat recovery, and use of catalyst to reduce ignition temperature. 

The use of catalyst was not assurled fn the above estimate. 

8'.3.4 Lime Kilns 

Three levels of control are being considered for this affected 

facility. The level of 40 ppn represents process controls of adding 

more air and raising the cold-end temperature of the kiln by 100" F. 

Adding a fan and instrumentation are assumed to be the required cost 

items, 

available costs for fans and instrumentation. These costs were then 

In-house EPA estimates of costs were generated on the basis of 

reviewed with industry personnel for comparison with actual modification 

costs for lime kilns. 

The level of 20 ppm represents the combination of good lime mud 

washing and control of the kiln process variables. Costs were provided 

by companies on the basis of replacing centrifuges with vacuum drum 

filters and adding another mud washing stage. 

cost estimating purposes were approximately 0.5 ft /ton pulp for filtration and 12 to 21 hours of retention in the clarifier stage. 

NCASI guide1 ines") for 

2 

The level of 8 ppm represents the addition of caustic to the lime 

kiln scrubber as a complement to the aforementimed requirements for 

achieving 8 ppn. The costs for caustic addition are assumed to be the 

same as those reported in the Standards Support and Environmental Impact 

Statement. (1 01 

8-14 
The capital and annualized costs for the three control levels are 

presented in Table 8-5. 

should be discussed. 

costs for process controls was based on use of 142 million BTU fuel for a 

1000 ton per day mill. 

There are three points concerning Table 8-5 that 

First, the fuel penalty assumed in the annualized 

This is the enthalpy requirement to raise the 

cold-end temperature of the kiln 100" F. Second, either process controls 

or combined process controls with mud washing may not achieve the 40 ppm 

level. 

and would have to add another lime kiln unit. 

industry indicate that a kiln addition in the range of 160-200 TPD (CaO 

basiS) seemed typical , regardless of mill size. 

are $3 million; and annualized costs, $510,000. 

In this circumstance, the mill may be short on lime burning capacity 

Results from surveying the 

Capital costs for the kiln 

For this mill, the kiln 

addition plus process controls on the existing kiln would be the requirement 

to achieve 40 ppm. 

Lastly, the costs in Table 8-5 are presented to demonstrate retrofit 

problems with mud washing. 

To take account of this, costs were estimated for a low retrofit and a high 

retrofit case. 

be rnlated to space limitation, replacement of the entire washing system, 

or changing condensate wash water to fresh water by addition of a condensate 

Results from the industry survey varied widely. 

Some of the problems associated with high retrofit costs may 

stripper. 

8.3.5 Black Liquor Oxidation Vents 

The control techniques for achieving the 5 ppm level of TRS emissions 

from black liquor oxidation system vents are incineration and the use of 

mol-ecular oxygen for oxidation. The vent gases may be combined with the 

brown stock washer vents and destroyed in the recovery furnace or separate 

8-15 
Table 8-5. RETROFIT CONTROL COSTS FOR LIME KILNS 

A. Process Controls (1 1 

Mill Size, TPD 500 . 1000 1500 

Capital Costs ($) 75,000 100,000 200,000 

Annual ized Costs ($/Yr. ) 54,000 107,000 175,000 

Annualized Costs per Ton ($/T) 0.33 0.33 0.36 

B. Mud Washing Capacity - Low Retrofit Penalty (2) 

Mill Size. TPD 500 1000 1500 

Capital Costs ($) 

Annualized Costs ($/Yr. ) 

Annualized Costs per Ton ($/T) 

480,000 730 , 000 

91,200 139,000 

0.56 0.42 

950,000 

181,000 

0.37 

i 

C. Mud Washing Capacity - High Retrofit Penalty (3) 

9" 

4 

m 

Mill Size, TPD 500 1000 1500 

Capit~l Costs (8) 960 , 000 1,460,000 ~,900,000 

Annualized Costs ($/Yr.) 182,000 278,000 362 , 000 

Annualized Costs per Ton ($/T) 1.11 0.85 0.73 

D. Caustic Addition 

Nil1 Size, TPD 500 1000 1500 

Capital Costs (8) -0- -0- -0- 

Annual i zed Costs ($/Y r. ) 3000 6000 9000 

Annual ized Costs per Ton ($/T) 0.02 0.02 0.02 

(1) In some situations, mills may be short on lime burning capacity. Typical capacity requirements 

might be on the order of 160 to 200 TPD CaO, which was fouund to be independent of mill size, 

Capital costs would be $3 million; annualized costs of $510,000 per year. 

(2) Includes only additional filtration and clarifier capacity. 

(3) Includes condensate stripper for removal of TRS from water used for mud washing and/or charges 

for space 1 imitation. 
incinerator. However, incineration costs for the BLO vents will be considered separately from the brown stock washers. 

Costs for incineration in recovery furnaces were taken from the costs 

developed for new sources. (''I Very few responses were received from industry, but one company did report similar costs, ('*) which were found to be 

comparable with EPA estimates. 

developed on the basis of a 26,000 scfm incinerator required for a 1000 

ton per day mill. 

Costs for separate incinerators were 

The source of the basic cost information was information 

provided by the Industrial Gas Cleaning Institute. (13) Costs for a 500 ton 

per day and 1500 ton per day were developed by using a scale factor of 0.3. 

Fuel requirements were calculated to be 19 million BTU per hour for the 

26,QOO scfm incinerator on the basis of using primary and secondary heat 

recovery. No casts for separate incineration were reported from industry. 

Costs for molecular oxygen were developed on the basis of 45 tons 

oxygen per 800 ton pulp produced. (14) 

pressure oxygen plants were obtained from Airco, Inc. (15) The energy consumption for use of molecular oxygen is assumed to be 20 kilowatt-hours per 

Capital costs for skid-mounted lowton of pulp, or 380 kilowatt-hours per ton of oxygen produced, (16) 

A sumnary of capital and annualized costs for control of black liquor 

oxidation vents is presented in Table 8-6. 

recovery furnace should reflect minimal retrofit problems, On the other 

The costs for incineration in a 

hand, separate incineration and molecular oxygen should represent high 

retrofit costs. 

8.3.6 Smelt Dissolving Tank 

The control strategy for achieving 8 ppm is the use of fresh water in 

a scrubber. This scrubber should already be installed in most mills because 

of state regulations for controlling particulates. The use of fresh water 

8-17 
Table 8-6. RETROFIT CONTROL COSTS FOR BLACK LIQUOR OXIDATION VENTS 

I I 

Mill Size, TPD 

Capital Costs ($) 

Annualized Costs ($/Yr. ) 

Annualized Costs per Ton ($/T) 

1000 

330,000 

96,000 

0.29 

500 

220,000 

60,000 

0.37 

1500 

432,000 

133,000 

0.27 

Mill Size, TPD 500 

Capital Costs ($) 400,000 

Annualized Costs ($/Yr.) 233,000 

Annual ized Costs per Ton ($/T) 1.42 

1000 1500 

560,000 700,000 

420,000 605 , 000 

1.28 1.23 

Mill Size, TPD 

Capital Costs (8) 

Annualized Costs ($/Yr.) 

Annual ized Costs per Ton ($/T) 

1000 

1,640,000 

509,000 

1.55 

500 

1,080,000 

309,000 

1.88 

1500 

2,100,000 

645,000 

1.31 
isthe only additional requirement which may be needed to reduce the 

effect ivel y. 

It is expected that costs associated with use of fresh water \nl 

TRS 

11 be 

small. 

particulate scrubbers on this affected facility on one mill, 

this example, no other cuinpany reported any cost for substituting fresh 

water for process water with high sulfides content. 

8.3.7 Condensate Strippers 

During the survey, one company provided cost data for inshall ing 

Other than 

Th 

in the 

furnace 

co nden s 

densate 

control technique for achieving the 5 ppm level is incineration 

ime kiln for steam stripping and incineration in the recovery 

for air stripping. 

te strippers. 

stripper vents. 

Only five mills in the U.S. presently employ 

Four of these mills are presently incinerating conThose mills that may decide to install condensate strippers in the 

(171 future are assumed to incur costs similar to reported costs for new sources. 

Those costs which are in 1976 dollars are summarized in Table 8-7. These 

costs include a fan, duct, seal pot, and flame arrester with the incineration point being the lime kiln. No retrofit penalty has been assigned 

because there are very few condensate strippers in existing mills. 

controls for new strippers should incur minimal retrofit costs. However, 

it still is possible that some retrofit penalty could be incurred if prior 

provisions have not been made to tap into the mill's piping system for 

venting other noncondensibles to an incineration point within the mill. 

Future 

8-19 
Table 8-7. CONTROL COSTS FOR COND'ENSATE STRIPPER 

500 1000 I 

Tu Mill Size, TPD 

O/ 

1500 

Capital Cost ($) 

Annualized Costs 

Annualized Costs 

16,200 

6',30O 

,I 

0.04 

22,700 

7,800 

0.02 

28,100 

8,900 

0.02 
8.4 Incremental Costs For Model Mills 

The purpose of this section is to present incremental control costs 

over requirements for state regulations, on a total mi 11 basis. 

into account the interrelationships involved with the many significant 

To take 

factors in estimation of retrofit costs, three model mill situations will 

be utilized to depict costs. These model situations are described as 

follows: 

(1) a post-1965 modern mill 

(2) 

(3) 

The modern mill has a recovery furnace of modern design that can 

an old (pre-1965) mill with low retrofit penalty 

an old (pre-1965) mill with high retrofit penalty 

a 

achieve the 5 ppm level under good operating conditions. The black liquor 

burning unit may be either a direct contact furnace or an indirect contact 

furnace. 

1967. 

will be for secondary black liquor oxidation to assure achievement of the 

5 ppm level. 

The latter type of furnace has been installed in mills only since 

Only the direct contact furnace will incur any control costs, which 

As for as the remaining affected facilities, only low retrofit costs are assumed to be incurred. 

The old mill built before 1965, with low retrofit penalty, is assumed 

to have a recovery furnace(s) capable of achieving the 20 ppm level. 

Furnace replacement costs would be incurred only for a 5 ppm system. 

the remaining affected facilities, low retrofit costs would be associated 

wi th addi ti on of controls . 

On 

The old mill built before 1965, with a high retrofit penalty, is 

assumed to have a recovery furnace(s) that cannot achieve the 20 ppm 

level. This may be due to a very old furnace, greater than 20 years of age, 

2-21 
or insufficient black liquor burning caPacity. 

condition is that a new furnace will be required for all control systems. 

The remaining affected facilities will incur high retrofit costs with the 

addition of control. 

The result of this 

The next lmportant factor influencing incremental costs is the 

variability in state regulations. 

emission control regulations for existing sources. One set of costs will 

be presented for such states. 

which call for cortrols on existinq recovery furnaces and incineration of 

noncondensible gases from miscellaneous sources such as digesters , mu1 tiple 

6ffect evaporators, and condensate strippers. Another set of incremental 

costs will be presented for such states. Very few states, perhaps one or 

two, require controls on exl’stinq lime kilns, and no states require controls 

on existinq brown stock washers and black liquor oxidation system vents. 

Some states with pulp mills have no 

Many states with pulp mills have regulations 

Tables 8-8 and 8-9 present incremental costs for a modern mill under 

the two regulatory situations as described earlier. Capital and annualized costs are presented for the six alternative control systems detailed 

in Table 8-1. 

contact recovery furnace designs. 

liquor oxidation system vents, costs are presented only for destruction in 

a separate incineration. 

not be widely applicable due to attendant problems of inflexibility and 

possible explosions, as pointed out in Chapter 6. 

Costs are presented for the direct contact and indirect 

For brown stock washers and black 

Destruction of TRS in the recovery furnace may 

Where no regulations exist (Table 8-8) , incremental annualized control 

- costs for the model mill with the direct contact recovery furnace range 

from $1.73 per ton for control system 6 to $8.53 per ton for system 1. For 

8-22 
Table 8-8. INCREMENTAL RETROFIT CONTROL COSTS FOR A 1000 TPD MODERN MILL (BUILT AFTER 1965) 

Location: State with No Regulations 

No. 1 

Unit 

CaDital Anpualized Annualized 

costs costs costs 

j$lOOO) ($looO/yr) ($/TI 

A. Recovery Furnace 

a) Direct Contact 1,000 242 0.74 

b) Indirect Contact 0 0 0 

B. Batch Digester and (1) 

C. Brown Stock Washers (2) 

System Ventsyz) 

(Direct Contact Only) 

E. Lime Kiln (3) 

Multiple Effect Evaporator 900 21 0 0.64 

2,500 1,670 5.08 

D. Elack Liquor x'dation 560 420 1.28 

830 252 0.77 

F. Condensate Stripper 23 8 0.02 

03 TOTAL COSTS 

r\) a) Direct Contact 5,813 2,802 8.53 

w b) Indirect Contact 4,253 2,140 6.51 

I 

No. 2 

Capital Annual ized Annual i zed 

costs costs costs 

~$1000) ($lOOO/yr) ($IT) 

Unit 

1,000 242 0.74 

0 0 0 

900 210 0.64 

0 0 0 

0 0 0 

830 252 0.77 

23 8 0.02 

2,753 71 2 2.17 

1,753 470 1.43 

No. 3 

Unit 

Capital Annualized Annualized 

costs costs costs 

I810001 I$1ooO/yr) ($/T) 

1,000 242 0.74 

0 0 0 

900 21 0 0.64 

0 0 0 

0 0 0 

830 252 0.77 

23 8 0.02 

2,753 71 2 2.17 

1,753 470 1.43 

No. 4 No. 5 

A. Recovery Furnace 

a) Direct Contact 1,000 242 0.74 

b) Indirect Contact 0 0 0 

B. Batch Digester and (1 1 

C. Brown Stock Washers (2) 0 0 0 

Udation 

Mu1 ti pl e Effect Evaporator 900 21 0 0.64 

D. Black Liquor .o 0 0 

E. Lime Kiln(') 830 246 0.75 

System Vents 

(Direct Contact Only) 

F. Condensate Stripper 23 8 0.02 

TOTAL COSTS 

a) Direct Contact 2,753 706 2.15 

b) Indirect Contact 1,753 464 1.41 

- .- -.. 

1,000 242 0.74 

0 0 0 

900 21 0 0.64 

0 0 0 

-0 0 0 

100 107 0.33 

23 8 0.02 

2,023 567 1.73 

1,023 325 0.99 

1,000 242 0.74 

0 0 0 

900 21 0 0.64 

0 0 0 

0 0 0 

100 107 0.33 

23 8 0.02 

2,023 567 1.73 

1,023 325 0.99 

(1) Low retrofit penalty 

(2) Destruction in separate incinerator 

(3) Low retrofit penalty 
Table 8-9. IEICREHENTAL RETROFIT CONTROL COSTS FOR A 1000 TPD MODER MILL (WILT AFTER 1965) 

State with Typical Regulationsyl 

aJ 

N 

P 

Location: 

No. 1 

Unit 

Capital Annualized Annualized 

costs costs costs 

I$lOOO) ($1000/yr) ($/T) 

A. ,Recovery Furnace 

a) Direct Contact 1,000 242 0.74 

b) Indirect Contact 0 0 0 

Multiple Effect Evaporator 0 0 0 

B. Batch Digesters and 

C. Brown Stock Washers (*) 2,500 1,670 5.08 

D. Black Liquor xidation 560 420 1.28 

System Vents 'I 2) 

(Direct Contact Only) 

E. Lime Kiln(3) 830 252 0.77 

F. Condensate Stripper 0 0 0 

TOTAL COSTS 

a) Direct Contxt 4,890 2,584 7.87 

b) Indirect Contact 3,330 1,922 5.85 

- 

No. 4 

A. Recovery Furnace 

a) Direct Contact 0 0 0 

b) Indirect Contact 0 0 0 

Multiple Effect Evaporator 0 0 0 

C. Brown Stock Washers (2) 0 0 0 

D. Black Liquor x dation '0 0 0 

B. Batch Digester and 

System Vents (121 

(Direct Contact Only) 

E. Lime Kiln(3) 830 246 0.75 

F. Condensate Stripper 0 0 0 

TOTAL COSTS 

a) Direct Contact 830 246 0.75 

b) Indirect Contact 830 246 ' 0.75 

No. 2 

Unit 

Capital Annualized Annualized 

costs costs costs 

i$lOOO) l$1000/yr)- ($/TI 

1,000 242 0.74 

0 0 0 

'0 0 0 

0 0 0 

0 0 0 

83 0 252 0.77 

0 0 0 

1,830 494 1.50 

830 252 0.77 

No. 3 

Unit 

Capital Annualized Annual ized 

costs costs costs 

($1000) j$1000/yr) ($/T) 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

830 252 0.77 

0 0 0 

830 252 0.77 

830 252 0.77 

1;o. 5 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

100 107 0.33 

0 0 0 

1 OG 107 0.33 

100 107 , 0.33 

No. 6 

1,000 242 0.74 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

100 107 ' 0.33 

0 0 0 

1,100 349 1.07 

100 107 0.33 

(1) A typical state is assumed to require 20 ppm for the recovery furnace and incineration (5 ppm) of TRS emissions from digesters, multiple 

(2) Destruction in separate incinerator. 

(3) LOW retrofit penalty 

effect evaporators , and condensate strippers. 
the indirect contact furnace, the model mill incurs incremental annualized 

control costs ranging from $0.99 per ton for system 6 to $6.51 uer ton 

for system 1. In states with the typical composite of regulations (Table 

8-9), incremental annualized control costs range from $1.07 per ton for 

system 6 to $7.87 per ton for system 1 in a mill with a direct contact 

furnace. For the mill with the indirect contact furnace, incremental 

annualized costs for these respective systems range from $0.33 per ton to 

$5.85 per ton. 

For modern mills, the most significant cost is that associated with 

incineration of brown stock washer gases. 

-facility alone is $5.08 per ton for system 1 (Table 8-8 and 8-9) of which 

$3.59 oer ton is a fuel penalty. The fuel penalty would not be incurred 

in some mills where the washer qascs can be incinerated in a recovery furnace. 

It should be noted that the rather significant $1.28 per ton cost for 

controlling black liquor oxidation system vents only occurs for the mill 

with a direct contact furnace. 

Tables 8-10 and 8-11 present control costs for an old mill with a low 

The control of this affected 

retrofit penalty. Capital and annualized costs are presented for the 

six alternative control systems detailed in Table 8-1. The costs for 

control of brown stock washers and black liquor oxidation system vents is 

based on separate incineration. 

assumed to be required for systems 1, 2, and 6. Furthormore, the furnace 

is assumed to have ample capacitv to support the mill's normal production 

needs. This assumption eliminates any consideration of additional furnace 

investment for systems 3, 4, and 5. 

The replacement of the recovery furnace is 

Where no state regulations exist (Table S-lC)), incremental annualized 

8-25 
Table 8-10. INCREMENTAL RETROFIT COVTR9L COSTS FOR A 1090 TPD OLD MILL (BUILT BEFORE 1965) - LOW RETROFIT PENALTY 

‘ Location: State with No Requlations 

No. 1 

Unit 

Cap4 tal Annual 1 zed Annualized 

costs costs costs 

($1099) ($lr)O?/yr) ($/T) 

A. Recovery FurnaceIl) 23,300 4,000 12.18 

8. Batch Digester and 

Multiple Effect Evaporators 900’ 211) 9.64 

C. Brown Stock Washers (2) 2,500 ., ,670 5.08 

9. Black Liquor Orijation System Vents 560 420 1.28 

E. Lime Kiln 839 2 52 n. 77 

F. Condensate Stripper 23 8 0.02 

28,113 6,560 19 :97 TOTAL COSTS 

01 No. 4 -- 

A. Recovery Furnace(’ 1,000 242 i. 74 

C. Brown Stock Washers(2) 0 0 9 

B. Batch Digester and 

Multiple Effect Evaporators 900 210 9.64 

D. Black Liquor xidation 

System Vents 1 2) 9 1) 9 

E. Lime Kiln 890 246 ‘1.76 

F. Condensate Stripper 23 8 9.02 

TOTAL COSTS 2,753 706 2.15 

No. 2 , 

Unit 

Capital Annual ized Annual i zed 

costs Costs Costs 

I$i939j ($19r)7/yr) ($/T) 

23,300 4,030 12.18 

9VJ 21 9 0.64 

9 3 3 

0 3 0 

839 252 0.77 

23 8 0.92 

25,953 4,470 13.61 

Yo. 5 

1,090 242 rJ. 74 

900 210 0.64 

0 3 0 

0 0 0 

10’0 197 0.33 

23 8 0.92 

2,923 567 1.73 

No. 3 

Unit 

Caai tal Annual i zed Annual i zed 

costs costs costs 

I$l997)- ($l09O/yr) ($/T) 

1,090 242 0.74 

0.64 

3 0 0 

939 210 

9 9 0 

830 2 52 9.77 

23 R 0.02 

2,753 712 2.17 

Vo. 6 

23,390 4,093 12.18 

903 213 9.64 

9 3 0 

9 0 0 

100 107 0.33 

23 8 0.02 

24,323 4,325 13.17 

Recovery fumice would be a direct contact furnace only 

(2) Destruction in separate incinerator 
Table 8-11. INCREMENTAL RETqOFIT COIITROL COSTS'FOR A 1000 TPD OLD MILL (BUI BEFORE 1965) - LOW RETROFIT PEIIALTY 

Location: State with Typical Regulations 1 

Unit 

Capital Annualized Annualized 

costs costs costs 

($1000~ l$1000/yrl ($/TI 

hl 1 

Unit 

Capital Annualized Annualized 

costs costs costs 

($1000) j$1000/yr) ($/TI 

A. Recovery Furnace 23,300 4,000 12.18 

B. Batch Digesters and 

C. Brown Stock Washers (2) 2,500 1,670 5.08 

Multiple Effect Evaporators 0 0 0 

Unit 

Capital Annualized Annualized 

costs Costs costs 

i$lOOO) I$1000/yr) ($/TI 

D. Black Liquor Oxidation 560 420 1.28 

System ~ents(2) 

E. Lime Kiln 

F. Condensate Stripper 

830 252 0.77 

0 0 0 

TOTAL COSTS 27,190 6,342 19.31 

23,300 4 , 000 12.18 

0 0 0 

0 0 0 

0 0 0 

830 252 0.77 

0 0 0 

24,130 4,252 12.95 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

830 252 0.77 

0 0 0 

830 252 0.77 

A. Recovery Furnace 

B. Batch Digesters and 

Mu1 tiple Effect Evaporators 

C. Brown Stock Washers (2) 

E. Lime Kiln 

F. Condensate Stripper 

No. 4 

Unit 

Capital Annualized Annualized 

costs costs costs 

($1000) ($1000/yr) ($/TI 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

830 246 0.75 

0 0 0 

TOTAL COSTS 830 246 0.75 

No. 5 

Unit 

Capital Annualized Annualized 

Costs costs costs 

($1000) :$100c;/yr) ($/TI 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

100 107 0.33 

0 0 0 

100 107 0.33 

No. 6 

Unit 

Capital Annualized Annual ized 

costs costs costs 

($1000) ($1000/yr) ($/TI 

23,300 4,000 12.18 

0 0 0 

0 0 0 

0 0 0 

100 107 0.33 

0 0 0 

23,400 4,107 12.51 

(1) A typical state is assumed to require 20 ppn for the recovery furnace and incineration (5 ppm) of TRS emissions from digesters, multiple effect 

(2) Destruction in separate incinerator. 

evaporators, and condensate strippers 

I 
costs range from $1.73 per ton to $2.17 per ton for systems 3, 4, and 5. 

The incremental annualized costs for systems 1, 2, and 6 range from $13.17 

to $19.97 per ton. The replacement of the recovery furnace is responsible 

for $12.18 per ton of these costs. 

In a state with typical regulations, incremental annualized costs 

range from $0.33 to $0.77 per ton for systems 3, 4, and 5. 

1, 2, and 6, incremental annualized costs range from $12.51 per ton to 

$19.31 per ton, the most expensive being system 1. 

replacement is responsible for $12.18 per ton. 

For systems 

Again, recovery furnace 

Tables 8-12 and 8-13 present control costs for the old model mill with 

a the incidental high retrofit penalty. Capital and annualized costs are 

presented for the six alternative control systems similar to the previous 

models. Costs of control for the washer gases and the oxidation vents is 

based on separate incineration. The construction of new furnace sized to 

support the entire 1000 ton per day mill is assumed in the cost estimates 

for: 

control systems 1, 2, and 6 in states with typical regulations. 

of the high retrofit costs for this model mill involve the controlling of 

the digestors/evaporators and the lime kiln. 

with the lime kiln, namely additional requirements for lime mud washing 

and additional lime burning capacity, have been taken into account for this 

model mill. In summary, Table 8-12 would represent the worst situation - - 

an old mill with incidental high retrofit penalties in a state with no 

regulations. 

(1) all control systems in states with no regulations, and (2) 

The aspects 

The two factors associated 

Where no regulations exist (Table 5-12), incremental annualized costs 

- range from $15.46 per ton for system 6 to $22.68 per ton for system 1. 

furnace costs are responsible for $12.18 per ton of these costs. 

New 

In 

8-28 
A. 

B. 

c. 

0. 

E. 

F. 

(1 1 Recovery Furnace 

Table 8-12. INCREMtl.(TAL RETROFIT COtiTROL COSTS FOR A 1000 TPU OLD IlILL (BUILT CEFORI: 1965) 1 HIGH RETROFIT PEI!ALTY 

Location: State Kith No Regulations 

No. 1 No. 2 No. 3 

Unit Unit Unit 

Capital Annualized Annual ized Capital Annual ized Annualized Capital Annualized Annualized 

costs costs costs costs costs costs costs costs costs 

($1000) I$1000/yrl ($/TI l$loOO). ($1000/yrl ($/T) ($1 000) J$lOOO/yr) ($/TI 

23,300 4,000 12.18 23,300 4,000 12.18 23,300 4,000 12.18 

2,000 452 1.38 2,000 452 1.38 2 , 000 452 1.38 Ratch niystcr and 

Brown Stock Washers 

Multiple Effect Evaporator 

(2) 2,500 1,670 5.08 0 0 0 0 0 0 

. 560 420 1.28 0 0 0 0 0 0 

(3) 4,560 901 2.74 4,560 ' 901 2.74 4,560 901 2.74 Lime Kiln 

23 8 0.02 23 8 0.02 23 8 0.02 Condensate Stripper 

TOTAL COSTS 3z ,943 /,451 LZ. b8 L9,883 S,Jbl 16.2 LY ,883 5,361 16.32 

I No. 4 No. 5 No. 6 

.D A. Recovery Furnace n ,300 4.000 12.18 23,300 4,000 12. I8 n,300 4 ,00u IZ. 18 

2,000 452 1.38 2,000 452 1.38 2,000 452 1.38 

m _- N 

B. Batch Digester and 

C. Brown Stock Washers 

0. Black Liquor x'dation 

E. Lime Kiln 

F. Condensate Stripper 

Mu 1 ti pl e Effect Evaporator 

(2) 0 0 0 0 0 0 0 0 0 

0 0 0 0 0 0 0 0 0 

System Vents 921 . 

(3) 4,560 896 2.73 3,100 61 7 1.88 3,100 61 7 1.88 

23 8 0.02 23 8 0.02 23 8 0.02 

TOTAL COSTS cy, 883 5,355 16.30 28,401 5 , 071 15.46 28,401 5,071 15.46 

(1) Recovery furnace - direct contact only. 

(2) Destruction in separate incinerator. 

(3) High retrofit expenditures for the following: 

Furnace with an assumed age exceeding twenty years would have to be replaced for each control strategy. 

addition of a new lime kiln for each control strategy and addition of condensate stripper for 

strategy numbers 1 through 4. 
A. ile*.overy Furnace 

E. Sa ch Digester and 

C. Br,:in Stock Washers 

3 E: ck Liquor xidation 

'hl ti 01 e Effect Evaporators 

(2) 

:) stem Vents 9 2) 

i. Li e Kiln (3) 

F. Co densate Stripper 

No. 2 

I No. 1 

IS1 000) IS1 000/yr 1 ($/TI 

23,300 4,000 12.16 

0 0 0 

2,500 1,670 5.08 

560 420 1.28 

4,560 901 2.74 

0 0 0 

Unit 1 Unit 

($1000) (b1000/yr) ($/TI 

23,300 4,000 12.18 

0 0 0 

0 0 0 

0 0 0 

4,560 901 2.74 

0 0 0 

-- 

TOTAL COSTS 30,920 6,991 21.28 

co -. - - 

0 

w No. 4 

Unit 

Capital Annualized Annualized 

costs costs costs 

j $1 000) ($1 0@0/yr) ($/T f 

A. Rerwkry Furnace 0 0 0 

P. Gatch Digester and Multiple 0 0 0 

0 0 0 

-ffect Evaporators 

(2) C. Br, ./n Stock Washers 

?3fa D. El,.k Liquor 0 

lvstem Vents 

0 0 0 

E. Lii,: Kiln(3) 4,560 896 2.73 

F. Cor lensate Stripper 0 0 0 

TOTAL IOSTS 4,560 896 2.73 

27,860 4,901 14.92 

No. 5 - 

Unit 

Capital Annualized Annual ized 

costs costs costs 

l$lOOO). ($1000/yr) ($/TI 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

3,100 617 1.88 

0 0 0 

3,100 61 7 1.88 

' Unit 

Capital Annual ized Annual i zed 

costs Costs costs 

($1000) ($1000/yr) ($/TI 

0 0 0 

0 0 0 

0 0 0 

0 0 0 

4,560 901 2.74 

0 0 0 

4,560 901 2.74 

No. 6 

Unit 

Capital Annuallzed Annualized 

costs costs Costs 

($1000) ($1000/yrl (S/T I 

23,300 4,000 12.18 

0 0 0 

0 0 0 

0 0 0 

3,100 61 7 1.88 

0 0 0' 

26,403 4,617 14.05 

(1) A ypical state is assumed to require 20 ppm for the recovery furnace and incineration (5 ppm) of TRS emissions from digesters, multiple effect 

e: !p3rators, and condensate strippers. 

(213 5iruction in separate inciqerator 

(2) igh retrofit expcnditures =or the followinc: addition of a new lime kiln for rach control systeiii and addition of 

' w!ensate stripner for sYstel,, numbers 1 througb 4. . 
states with typi cal regul ati ons , the incremental annual i zed costs ranqe 

from $14.06 per ton to $21.28 per ton for control systems 1, 2, and 6, 

with system 1 being most expensive. For control systems 3, 4, and 5, t'7e 

incremental annualized costs range from $1.88 per ton to $2.74 per ton. 

From the previous discussion on old mills, the most significant 

factor that frequently re-appears in the total mill costs has been requirements for new recovery furnace investment. Up to this point all capital 

related charges dssociated with purchasing, installing, and ownershiP of 

the recovery furnace have been presented as control costs. However, the 

recovery furnace is a productive capital asset in the sense that it 

coneributes to the economics of pulp production with recovery of ensrq,y 

and chemicals. 

deducted from the control costs. However, it is ver.y difficult to estimate 

this credit on a source by source basis in terms of dollars per ton. 

Consequently, some credit for a productive asset should be 

Therefore , no credit was deducted. 

The extent of credit to be deductible is very source specific. The 

amount of credit would depend on the remaining economic 1 fe of existing 

furnace equipment. In a specific mill the recover,y furna e could be very 

old. like thirty years of age, and very inefficient. 

probably be scheduling for the replacement of the old furnace in the near 

future. Here, the replacement cost should be treated as a normal productive asset with no credit given for control costs. 

recovery furnace may have a significant amount of residual economic life, 

say 15 years. 

force the scrapping and replacement of this recovery furnace. 

situation, the capital value foreaorle in scrappinq the furnace sClould be 

Such a mill would 

In another mill , a 

Suppose a state should require a 5 ppm level which would 

In this 

8-31 
the approximate control cost. 

In a similar vein, mills that tend to overload 

be required to provide additional black liquor burn 

TRS emissions. The incremental capacity sufficient 

recovery furnaces may 

ng capac ty to reduce 

to reduce the emissions 

to a satisfactory level should be the approximate control cost although a 

mill would install a complete new recovery unit which would exceed the 

necessary incremental capacity. 

8.5 Aggregate Costs For Industry 

In this section the estimated incremental control costs are reported 

for the existing kraft pulp industry for the six alternative emission 

control systems outlined in Table 8-1. 

these costs for each individual mill on the basis of the best technical 

information avai lab1 e for each mi 11 regarding production rates, furnace 

capacity and age, type of controls used, status of state regulations, and 

other technical parameters. Section 8.3, Costs For Affected Facilities, 

which relates control costs as a function of mill size was used to make 

the estimates. 

considered suitable to estimate total industry costs because of the wide 

vari abi 1 i ty in mi 11 characteristi cs and state regul atory requirements. 

ever, the two approaches should give consistent results. 

the model mill approach with the results obtained by the individual mill 

approach does support this claim. 

The approach used was to estimate 

The model mill approach as outlined in Section 8.4 was not 

HowVerification of 

Actual cost information received from 42 mills during the EPA industry 

survey was used to derive the Section 8.3 costs. 

Qf capital and annualized were made individually for 77 mills which were not 

contacted in the industry survey. 

From these costs, estimates 

The costs for these mills were then 

5-32 
combined with the actual costs received for the 42 surveyed mills to 

derive industry totals. 

The summary of industry incremental costs are reported in Table 8-14 

for each system. Capital and annualized costs are presented for industry 

totals and on a unit basis. In addition, incremental capital costs are 

related to mill investment as a measured percentage. The investment for a 

battery limits mill is $150 million in 1976 dollars, which was derived 

from a study for EPA's Office of Solid Waste Management.('*) Similarly, 

incremental annualized costs are related to the market pulp price as a 

measured percentage. 

quoted contract price for domestic bleached kraft pulp. (I9) 

represents the average of pulps derived from hard and softwoods. 

The price used was $330, which is the currently 

This price 

The i ndustry-wi de incremental annual i zed control costs range from 

$1.99 per ton for system 5 to $12.72 per ton for system 1. 

ton figure is predicated on the basis of replacement of 18 recovery 

furnaces and 3 lime kilns. 

basis of replacement of 63 recovery furnaces and 33 lime kilns. 

be noted that systems 3 and 4 would require replacement of 18 recovery 

furnaces and 33 lime kilns. 

market pulp price are 0.6 percent for system 5 ($1.99 per ton) and 3.9 percent 

for system 1 ($12.72 per ton). 

The $1.99 per 

The $12.72 per ton figure is predicated on the 

It should 

The corresponding percentages in relation to 

Capital requirements for incremental controls range from $10.32 per 

ton capacity for system 5 to $46.20 per ton for system 1. 

requirements for new mill investment, these estimates amount to 1.8 percent 

In relation to 

for system 5 and 8.1 per cent for system 1. 

- The approach used to develop industry-wide costs represents a composite 

8-33 
Table 8-14. Stmary of Idustry Xmvwemtrl Contml Coats *r Six Alternatives Control Strategies 

Total Capi tal ($1 OO'I) 

Capital , per ton 

capacity ($/T) 

Capital, as a percent 

of new mill(1) 

Total Annualized Costs 

(? ($1000/yr) w 

P 

Unit An; ialized Costs ($/T) 

Annualized costs, as a 

percenf2yf market pulp 

price 

40. 1 

1,6C12,000 

46.20 

8.1 

441,000 

12.72 

3.9 

No. 2 

1,275,000 

36.78 

6.5 

237,000 

6.84 

2.1 

No. 3 

495,000 

14.27 

2.5 

94,300 

2.72 

9.8 

No. 4 

49 5,000 

14.27 

2.5 

93,600 

2.70 

0.8 

No. 5 

358,090 

10.32 

1.8 

69,000 

1.99 

0.6 

No. 6 

1,148,000 

33.11 

5.8 

200,000 

5.76 

1.7 

(1)Capital Costs for New Battery Limits 809 TPD Mill is $150 million, or $570 per ton (1976 dollars) Source: 

Arthur D. Little, Reference 18. 

(2)Market pulp price is $330 per ton, based on fourth quarter 1976 prices for domestic kraft bleached pulp. 

Source: Paner Trade Journal. 
of many different types of state regulations and the individual character 

of 119 mills. Although the model mill approach in Section 8.4 was 

considered inappropriate to estimate industry costs, there should be some 

linkage between the industry-wide costs and the model mill costs on a unit 

basis. 

costs in Table 8-14 fall about midway between cost requirements for a 

modern mill in a state with typical regulations (Table 8-9) and for an old 

mill with low rdtrofit penalty in a state with no regulations (Table 8-10) 

for systems 1, 2, and 6. Industry-wide costs in Table 8-14 are somewhat 

higher than the costs reported for an old mill (Table 8-10) for systems 

3, 4, and 5. A conclusion would be that there is some reasonable agreement 

in the magnitude of the costs developed from the two separate approaches. 

8.6 Cost-Effectiveness 

A comparison of the two approaches revealed that the industry-wide 

An analysis was made to evaluate the cost-effectiveness of the six 

alternative emission control systems in terms of their contribution to 

reducing national TRS emissions. The cost-effectiveness technique is a 

useful tool in selecting an appropriate control system as a recommended 

guideline. In this selection, those control systems that have significantly 

high control costs in terms of their pollutant removal are rejected as 

viable control recomnendations. It should be strongly emphasized that the 

cost-effectiveness approach for recomnending controls is only applicable 

for welfare-related Ill-d pollutants, such as TRS. 

pollutants , an economic impact analysis is a requirement for determining 

affordabi 1 i ty of best control s . 

For health-related Ill-d 

The industry aggregate annualized control costs presented in Table 

8-14 and the national emission reduction data reported in Table 9-2 were 

8-35 
used to make the cost-effectiveness calculations. The results are 

presented in Table 8-15. The control systems are ranked in ascending 

order in terms of emission reduction and costs, starting with system 5 as 

the least expensive. Two calculations of cost-effectiveness are presented 

for each control system in columns (E) and (F). The calculation in 

column (E) simply represents the costs per ton removed by a particular 

control system. The calculation in column (F) represents the marginal costs 

per ton removed by a particular control system relative to a system of 

lower ranking. The marginal cost calculation is a more sensitive indicator 

in revealing the more expensive control system. For example, in Table 

8-15, system 6 costs $75,500 per ton marginally. 

significant than the $1750 for system 3 or $11,180 for system 4. 

This is much more 

With 

respect to actual cost per ton, system 6 costs $3000 per ton, which is 

significantly higher, to a lesser degree, than the approximate $1400 per 

ton for systems 4 and 3. 

Based on the data in Table 8-15, it would seem reasonable to reject 

control systems 6, 2, and 1 as not being cost-effective. System 5 might be 

considered a minimal strategy, costing $1060 per ton. 

and 3 cost somewhat more, about $1400 per ton, which would not seem to be of such 

Control systems 4 

a magnitude to preclude consideration of these control systems as a viable 

control technology. 

8-36 
Control System 

Table 8-1 5. COST EFFECTIVENESS DATA FOR ALTERNATIVE CONTROL SYSTEMS 

A 

National 

Emission 

Redu c t i on 

ton s/y r . 

65,000 

67 , 200 

67 , 600 

69 , 000 

71,500 

77,700 

B 

Marginal 

Emi s si o n 

Reduct ion 

tonslyr. 

65,000 

2,200 

400 

1 ,400 

2 , 500 

6,200 

C 

I n du s try 

Annual i zed 

Control 

costs 

$1 000/yr 

69 , 000 

93 , 600 

94 , 300 

200,000 

237,000 

441,000 

D 

Marginal 

Annualized 

Control 

costs 

$1 000/yr. 

69 , 000 

24,600 

700 

105 , 700 

37,000 

204,000 

E 

Annualized 

Costs per 

ton Removed 

($/ton> 

(C) '(A , 

1,060 

1,390 

1,395 

3 , 000 

3,315 

5,675 

~ 

F 

Marginal 

Annual i zed 

Cost per ton 

Removed 

(D) '( B) ,$/ton 

1,060 

11 ,180 

1,750 

75,500 

14,800 

32,900 
References for Chapter 8 

1. Post's 1973 Pulp and Paper Directory,Miller Freeman Publications, 

Inc., San Francisco. 

2. Lockwood's Directory of the Paper and Allied Trades, Lockwood Publishing 

Co., New York, 1974. 

3. Correspondence from Mr. Russell Blosser, National Council for Air and 

Stream Improvement, Inc., to Mr. Frank L. Bunyard, EPA, OAQPS, 

April 22, 1975. 

4. See Reference 3. 

5. Correspondence from Mr. C. T. Tolar, Rust Engineering Co., Birmingham, 

Ala., to Mr. Paul A. Boys, October 20, 1972. 

6. Correspondence from Mr. Russell Blosser, National Council for Air and 

Stream Improvement, Inc., to Mr. Paul A. Boys, November 17, 1972. 

7. Air Pollution Control Technology and Costs: Seven Selected Emission 

Sources , .I_?dustrial Gas Cleaning Institute, EPA-450/3-74-060, 

National Technical Information Service, Springfield, Va., December, 1974. 

8. Report of Fuel Requirements, Capital Cost and Operating Expense for 

Catalytic and Thermal Afterburners , CE Air Preheater for Industrial 

Gas C1 eaning Institute, EPA-450/3-76-031 , National Technical Information Service, Springfield, Va., September 1976. 

9. See Reference 3. 

10. Standards Support and Environmental Impact Statement - Volume I: 

Proposed Standards of Performance for Kraft Pulp Mil ls, EPA-450/2-76-014a 

National Technical Information Service, Springfield , Va. , September 1976. 

11. See reference ' 0. 

12. Correspondence from Mr. Joe Kol berg , Boise Cascade, to Mr. Frank L. 

Bunyard, OAQPS, EPA, May 1975. 

13. See reference 8. 

14. See reference 5. 

15. Telephone conversation from F. L. Bunyard, OAQPS, EPA, to George 

Horvat , Airco , Inc. , December 30, 1974. 

8-38 
I 

16. 

17. 

18. 

19. 

Investment and Operating Cost Data for Low Pressure Oxygen Plant 

Applicability to Non-Ferrous Metallurgy, Volcan - Cincinnati , EPA 

Contract No. 68-02-2099, Task No. 2, September 29, 1972. 

See reference 10. 

Analysis of Demand and Supply for Secondary Fiber in the U.S. Paper 

and Paperboard Industry, Volume 2: Section IX - Process Economics, 

Arthur D . Little Report for Contract #68-0l-02220, Environmental 

Protection Agency, Office of Sol id Waste Management Programs, March, 1975. 

Paper Trade Journal ? January 1 , 1977. 

8- 39 

a 

9. ENVIRONMENTAL IMPACT OF TRS CONTROLS 

niques and contro 

on the impacts on 

for a relatively 

a national basis. 

The environmental impacts discussed are for each of the control techsystems mentioned in Chapter 6. This includes discussions 

air, water, and solid waste pollution and energy consumption 

arge kraft pulp mill (907 megagrams of pulp per day) and on 

9.1 AIR POLLUTION IMPACT 

9.1.1 Annual Air Emission Reductions 

Installation of the various control techniques described in Section 6.1 

are estimated to reduce TRS emissions from the existing kraft industry by 

the amounts indicated in Table 9-1. Emission reductions range from 20.6 

percent for digester systems to 96 to 97 percent for digester systems and lime 

kiln systems. All values presented in Table 9-1 are based on information 

presented in Chapters 5 and 6 and Appendix A of this study. 

The following procedure was used to arrive at the numbers listed in 

Table 9-1. The values listed in Column 2 (Current National Average Emission 

Rate) were previously mentioned in Chapter 5 and are based on the information 

listed in Appendix A. 

various kraft pulp mills and state control agencies. Column 5 presents the 

percentage of existing facilities presently using the control techniques 

described in Column 2 as based on the information listed in Appendix A. 

values in Column 6 were developed by applying the emission level achievable by 

Information in Appendix A is based upon discussions with 

The 

9-1 
TABLE 9-1 

ENVIRONMENTAL IMPACT OF CONTROLLING THE 

VARIOUS TRS SOURCES IN A KRAFT MILL 

Source . . - -. . . . - - - . - - . - - - - - - - __ - 

Recovery Furnace 

Digester 

Mu1 tiple-effect 

Evaporator 

Lime Kiln 

W 

N 

Brown Stock Washer 

Black Liquor Oxidation 

Smelt Oi ssolving Tank 

Condensate Strippers 

System 

System 

Current 

National 

9!!9-_40_4 

1.25 

1.25 

0.32 

0.32 

0.22 

0.22 

0.31 

0.31 

0.31 

0.15 

0.05 

0.05 

0.10 

0.11 

0.11 

Averaqe 

Emission 

( WT AOPL 

Control .__ ____-I^-I Technique - 

(2.5) 8LO ( 20 PPI 

(2.5) BLO ( 5 ppm) 

(0.64) Scrubber 

(0.64) Incineration 

(0.43) Scrubber 

(0.43) Incineration 

(0.62) 1) Process Controls 

(0.62) 2) Process Control 6 High 

(0.62) 3) Process Controls. High 

Eff. Mud Washing 

Eff. Mud Washing & 

Caustic Scrubbfng 

(0.3) Incineration 

(0.1) ' Incineration 

(0.1) Molecular Oxygen 

(0.2) Fresh Water 

(0.22) Incineration 

(0.22) Scrubber 

Emission Level 

Achievable With 

Control Technique g/Kg ADP (# T/ADP) 

0.31 (0.6) 

0.08 (0.15) 

0.59 (1.17) 

0.04 (0.08) 

0.01 (0.02) 

0.01 (0.02) 

0.10 (0.2) 

0.05 (0.a) 

I of Capacity Not Presently Achieving This 

Level 

35.7 

86.9 

41.8 

42.4 

41.4 

45.9 

71 .8 

90.5 

Estimated Average National 

Eiission If Control 

Technique is Required g/Kg ADP (W T/ADP) 

0.25 (0.5) 

0.08 (0.15) 

0.26 (0.51) 

0.03 (0.05) 

0.01 (0.02) 

0.01 (0.02) 

0.09 (0.18) 

0.05 (0.1) 

0.021 (0.04) 99.4 0.021 (0.04) 

0.01 (0.02) 99.1 0.01 (0.02) 

0.01 (0.02) 98.0 0.01 (0.02) 

0 (0) 98.0 0 (0) 

0.013 (0.025) -- 0.01 (0.02) 

o.oi (0.02) 20 0.01 (0.02) 

0.5 (1.0) 0 0.11 (0.22) 

I Emission 

Rr4c t i on 

Nationally Achieved 

80.0 

94.0 

20.6 

96.9 

89.1 

95.3 

71.0 

84.0 

92.0 

93.3 

80.0 

100.0 

87.5 

90.9 

0 

National 

Emission Reduction 

M/year (tons_/y_e_arl 

31,200 (34.400) 

36,690 (40.450) 

2.040 ( 2,250) 

9,300 (10,700) 

5,940 ( 6,550) 

6,400 ( 7.050) 

6,900 ( 7,600) 

8,900 ( 9,800) 

9.300 (10,250) 

4,350 ( 4,800) 

1.270 ( 1,400) 

1,540 ( 1,700) 

2.800 ( 3,100) 

3,130 ( 3,450) 

0 (0) 
a particulate control device (Column 4) to those existing mills which are not 

presently achieving that level, as listed in Appendix A, and calculatinq the 

national average emission level that would result. Column 7 (Percent Emission 

Reduction Achieved Nationally) is the percent difference between Columns 2 and 6. 

The national emission reduction achieved by a specific control device (Column 8) 

was calculated by multiplying the difference between Columns 2 and 6 by the annual 

kraft pulp production rate (31,196,000 megagrams/year). 

Table 9-1 shows +.hat the greatest reduction of TRS emissions is achieved 

by controlling the recovery furnace system with the digester system, lime kiln, 

mu1 ti pl e-effect evaporator system, brown stock washer system, smel t di ssol ving 

tank, black liquor oxidation system and condensate stripping system following 

in decreasing impact. 

Table 9-2 shows the impact of the various control systems mentioned in 

Section 6.2.- For example, if System No. 1 (best available technology as 

defined for NSPS) was applied to each source, the TRS emissions from the kraft 

industry would be reduced by about 70,500 megagrams 

per year) or 94.2 percent. 

impact but would still reduce TRS emissions by about 59,000 megagrams per 

year (65,630 tons per year) or 78.8 percent. Control of four sources in a 

kraft mill account for a major portion of the impact achieved by each of the 

control systems. These four sources are the recovery furnace, digester system, 

multiple-effect evaporator system, and the 1 ime kiln. 

9.1.2 Annual Air Emission Increase 

per year (77,700 tons 

System No. 5, if applied, would result in the least 

II_-~-. 

The only control techniques mentioned in Chapter 6 that would apparently 

result in increasing the emission rates of other pollutants is the incineration 

of the vent gases from the brown stock washer systems and the black liquor 

9-3 
TABLE 9-2 

ENVIRONMENTAL IMPACT OF VARIOUS CONTROL SYSTEMS 

FOR EXISTING KRAFT PULP MILLS 

Estimate Average Na ti onal 

TRS Emission With % Emission 

Control Con tro 1 Sys tem Emission Reduction 

Sys t em g/Kg ADP (#T ADP) Re du c ti on* megagramslyear ( tons/year ) 

No. 1 0.14 (0.28) 94.2 70,500 (77,700) 

No. 2 0.32 (0.64) 

No. 3 0.44 (0.87) 

No. 4 0.45 (0.89) 

No. 5 0.51 (1.02) 

No. 6 0.40 (0.79) 

86.7 

81.9 

64,900 (71 ,500) 

61,300 (67,600) 

81.5 61,000 (67,200) 

78.8 59,000 (65,000) 

83.5 62,600 (69,000) 

* Based on a current control level of 2.4 g/Kg ADP (4.8 lb/T ADP). 

9-4 
oxidation systems if these gases are burned in a separate incinerator. 

emission rates of nitrogen oxides (NOx) and sulfur dioxide (SO2) from a mill 

would increase by the amounts emitted from this separate incinerator. 

natural gas was fired in the incinerator at a 907 metric tons per day (1000 

tons per day) mill, the NO and SO2 emissions resulting are estimated to be 

160 and 220 kilograms per day (350 and 480 pounds per day), respectively. 

These are in comparison with a TRS reduction of 180 kilograms per day (400 

pounds per day). 

of natural gas, the NO, and SO2 emissions resulting are estimated to be about 

380 and 1040 kilograms per day (840 and 2280 pounds per day), respectively. 

Using a gas-fired or oil-fired incinerator to burn these gases is a realistic 

alternative since the industry feels that burning these gases safely in a 

The 

If 

X 

Furthermore, if fuel oil (1% sulfur content) was used instead 

recovery furnace has not yet been demonstrated. 

burned in a-recovery furnace or power boiler, no increase in the SO2 or NOx 

emissions from these sources are expected. 

No increase in other pollutants is expected from burning the noncondensable 

However, if these gases were 

gases from the digester systems, multiple-effect evaporator system or condensate 

stripper system since these gases will normally be burned in a lime kiln as 

part of the normal combustion air. SO2 generated should be absorbed by the 

lime dust (calcium oxide) present in the kiln.’ The scrubbers used on most 

lime kiln systems also are effective gas removal system. 

emitted from the kiln system for this reason. 

Very little SO2 is 

9.1.3 Atmospheric Dispersion of TRS Emissions 

4 disDersion ;Inal.ysis was made on model kraft pulp mills to evaluate the 

impact of the various control techniques and retrofit systems on ground-level 

TRS concentration downwind of a kraft pulp mill. 

average design and layout as shown in Figure 9-1, and included the eight 

The models chosen were of 

9- 5 
FIGURE 9-1. Typfcal Plant Layout (1001 ton per day kraft pulp mill) 

W 

I 

m 

. 

i TREATMENT 

PONO 

!4 -25 

.-loo0 

H = 50 Stacks : 

- 24--C --- a t 1. Recovery Furnace 

2. Smelt Dissolving 

Tank 

3. Lime Kiln 

4. Digesters 

5. Evaporators 

6. Brown Stock Washers 

m 

7. Oxidation System 

8. Condensate Stripper 

'00 

TPIK@-> A = 40' , F = 60' 

B - 75' C 15' 

C = 50' H = 10' 

D= 35' J = 12' 

E = 60' K = 20' 

E 
affected facilities being considered. Modeling was performed for mills of 

500, 1000, and 1500 tons per day of air-dried pulp (ADP) produced, a range 

within which the majority of kraft pulp mill capacities fall. 

Maximum ground-level concentrations of TRS were determined for the emission 

rates corresponding to each control technique and system. The concentrations 

decreased predictably with decreases in the emission rates. 

to adjust the meteorological conditions of the study to achieve the worst cases 

that would be expected to occur at and near a kraft pulp mill. 

It was possible 

Ambient concentrations of TRS due to the a1 ternative control techniques 

and systems were calculated using state-of-the-art modeling techniques. 

calculations are assumed to be reliable within about a factor of two. The 

following assumptions were applied for the analytical approach: 

These 

1. There are no significant seasonal or hourly variations in emission 

rates for these mills. 

2. The-mills are located in flat or gently rolling terrain. 

3. The meteorological regime is unfavorable to the dispersion of effluents. 

This assumption introduces an element of conservatism into the analysis. 

Calculations were performed assuming the presence of aerodynamic downwash 

effects on the emissions. 

mill such as: 

stack; 

and (3) a two-foot stack for the black liquor oxidation tank atop a 50-foot 

building will result in downwash in most situations. Maximum ground-level 

concentrations were estimated by assuming worst meteor01 ogical conditions. 

The correlation of those estimates with observed concentrations at any particular 

kraft pulp mill would depend upon many factors, including the accuracy of the 

emission data, the mill configuration, the distance from the mill at which 

Unfavorable design characteristics of the model 

(1) a 220-foot structure adjacent to a 250-foot recovery furnace 

(2) a 175-foot smelt dissolving tank stack next to a 175-foot building; 

9- 7 
samples are obtained, the sampling period and the climatology of the mill 

location. 

The estimated maximum ambient TRS concentration (10 second average) 

in a vicinity of a 907 megagrams (1000 tons) per day pulp mill resulting from 

the individual affected facilities with and without controls are listed in 

Table 9-3. The maximum concentrations occur at 300 meters from the source. 

Table 9-3 shows that the sources (excluding the condensate strippers) resulting 

in the greatest impact on ambient concentrations of TRS are, in decreasing 

order, the digester systems, multiple-effect evaporator systems, recovery 

furnace, and the lime kiln. 

maximum ambient TRS concentration of 20,000 vg/m whereas an uncontrolled 

brown stock washer system results in a maximum ambient concentration of 370 

vg/m . Table 9-3 also shows the percent reductions of applying each control 

technique on uncontrolled levels and the ambient levels at various distances 

under the control led case. 

An uncontrolled digester system can result in a 

3 

3 

Tables similar to Table 9-3 showing the impact of applying controls to 

the various TRS sources on ambient TRS concentrations in terms of one-hour and 

24-hour averages and for 454 and 1350 megagrams (500 and 1500 tons) per day 

kraft pulp mills are included in Appendix C. 

all averaging period maximum concentrations are noted at extremely close-in 

distances (300 meters). This is due to considerable aerodynamic effect 

influencing the plume rise in each case. 

distances from the stack in question. 

the 300 meters given may be even higher. 

the frequency of occurrence for the maximum ambient concentration due to each 

source. 

For the stacks of each mill, 

The distances given in the tables are 

Concentrations closer to the stack than 

These tables also give an estimate of 

The TRS concentrations with low frequencies of occurrence are the 
TABLE 9-3 

W I 

(0 

IMPACT OF CONTROLLING Ttli VARIOUS TRS SOURCES ON 

AMBIENT TRS CONCENTRATION FROM A 907 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentraifon: ugh3 Frequency - (10 second avera e % of Concentrations 

Uncontrol led Distance fr%n Source (km) \Greater than 1/2 Percent 

Source Control Techniques Leyel @ 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum Reducti ona 

Recovery Furnace BLO (20 ppm) 

Digester Scrubber 

BLO (5 ppm) 

Incineration 

Mu1 tip1 e-Effect Scrubber 

Incineration Evaporator 

a ,030 320 210 120 50 28 96.0 

a ,030 a0 50 30 13 28 99.0 

20 ,000 15,290 5580 3550 3 23.5 

20,000 Ob 100.0 

3,750 310 200 120 

3,750 Ob 

4 91.7 

- 100.0 

Lime Kiln 1) Process Controls aoo 200 70 55 45 40 1 75.0 

2) Process Controls + aoo 50 20 15 11 10 1 93. a 

High Eff. Mud Washing 

3) Process Controls + High aoo 25 10 76 5 1 96.9 

Eff. Mud Washing + 

Caustic Scrubbing 

Srown Stock Incineration 37 0 25 96 34 93.2 

Idasher System 

Black Liquor Incineration 310 60 20 95 3 25 ao. 6 

31 0 OC - 100.0 Oxidation System Molecular Oxygen 

Smelt Dissolving Fresh Water 

Tank 

Condensate Stripping Scrubber 

Incineration System 

560 70 26 16 3 87.5 

14,000 7,000 975 525 

14,000 Ob 

a Reduction from uncontrolled averape level 

Gases are assumed burned in the lime kiln. The levels from the lime kiln 

include unburned TRS portion of these aases. 

C wrt aases. 

25 50.0 

- 100.0 
10-second and 1-hour concentrations from the smelt dissolving tank, the 

digesters, and the multiple-effect evaporators, along with all three averaging 

period concentrations from the lime kiln. 

of the averages during the year were above half the maximum value for the 

respective averaging periods. These maxima, then, appear to be caused by 

conditions of usually high wind speed which bring about aerodynamic downwash. 

In each case, less than 5 percent 

Table 9-4 shows the estimated maximum ambient TRS concentrations resulting 

from the various control systems. If System No. 1 (best available control 

technology) was applied to each source, the estimated maximum ambient TRS 

concentration would be 97 micrograms per cubic meter (10-second average). 

Control Systems No. 2 and No. 6 would reduce the average ambient TRS concentration 

around a kraft mfll to about 308 pg/m (10-second average). 

Control Systems No. 3 and No. 5 mild result in a maximum TRS ambient concentration 

of about 487 pg/m3 (10-second average). These concentrations are mainly caused 

by emissions from three facilities: the recovery furnace, the smelt dissolving 

tank, and the brown stock washer system. 

concentration due to emissions from the lime kiln and black liquor oxidation 

system are negligible in all cases. 

multiple-effect evaporators and condensate strippers since it is assumed that 

the gases from thew systems would be burned in the lime kiln. 

3 Application of 

Contribution to the maximum TRS ambient 

No values are reported for the digesters, 

Averaging tines of 10 seconds, one hour, and twenty-four hours were 

selected for the TRS calculations, representing short and long-term exposures. 

The 10-second average would be considered a "whiff", and applicable to the 

study of odorous emissions. 

level of exposure experienced through casual contact, while the 24-hour average 

shows the level of exposure of a person living riear the mill. 

The one-hour average gives an indication of the 

9-10 
TABLE 9-4. ESTIMATED IMPACT OF THE CONTROL SYSTEMS ON MAXIMUM AMBIENT TRS LEVELS 

AROUND AN EXISTING (907 MEGAGRAMS PER DAY) KRAFT PULP MILL 

Max mum 

Comb i ned CONTRIBUTION OF EACH SOURCE (ug/m 3 ) Control Averaging Concentration 

- SYLtE! Ti me pg/m3 RF S DT LK B LO 8SW 

1 

5 

6 

10 sec 

1 hr 

24 hr 

10 sec 

1 hr 

24 hr 

10 sec 

1 hr 

24 hr 

10 sec 

1 hr 

24 hr 

10 sec 

1 hr 

24 hr 

10 sec 

1 hr 

24 hr 

97 

30 

7 

3 08 

95 

24 

487 

150 

38 

4 87 

150 

38 

48 7 

150 

38 

3 Q8 

95 

24 

81 

25 

6 

260 

25 

6 

2 60 

80 

20 

260 

80 

20 

260 

80 

20 

81 

25 

6 

16 

5 

1 

16 

5 

1 

16 

5 

1 

16 

5 

1 

16 

5 

1 

16 

5 

1 

Neg . Neg . 

Neg . Neg . Neg . 

Neg . Neg . Neg . Neg . Neg . Neg . Neg . Neg. 

Neg . Neg . Neg . Neg . Neg . 

-- 

Neg . Neg . 

Neg . Neg . 

Neg . Neg . Neg . Neg . 

Neg . 

Neq. 

Neg * 

Neg . 

Neg. 

Neg . 

Neg . 

21 1 

65 

17 

21 1 

65 

17 

21 1 

65 

17 

21 1 

65 

17 

21 1 

65 

17 
9.1.4 _- Changes 11--- in Solid and Liquid Wastes 

Increased control of gaseous TCiS compounds will not change the amount of 

solid waste generated by the kraft pulp industry since none of the control 

techniques result in collecting solids that can not be recycled to the process. 

Water effluent from a mill may increase, however, due to the various TRS 

controls. Controls requiring use of fresh water instead of contaminated 

condensate will result in an increase in the mill effluent of the amount of 

the Condensate. 

stripper and reusing the stripped water. 

prevent the TRS dissolved in the condensate from being emitted from the treatment pond during aeration. Increasing the mud washing efficiency to control 

TRS emissions from the lime kiln can also increase the mill's water effluent. 

However, this additional effluent from the mud washer can probably be recycled 

back to the process. 

9.1.5 Energy Consumption 

This increase could be eliminated by using a condensate 

A condensate stripper would also 

The energy (fuel or electricity) required for each of the control techniques 

mentioned in Chapter 6 are listed in Table 9-5. 

resulting from a coal-fired power plant supplying the necessary power (electricity) 

for these control techniques are also listed in Table 9-5. 

As indicated in Table 9-5, the additional particulate, SO2 and NO emissions 

The additional eniissions 

X 

that will occur at a coal-fired power plant due to producing the electricity 

that will be required to control emissions is small compared to the TRS 

reduction that will be achieved at the kraft mill. 

As indicated by Table 9-5, the only control techniques requiring additional 

fuel consumption at a kraft mill are incineration (in a separate incinerator) of 

the vent gases from the brown stock washer system and the black liquor oxidation 

system, and process controls used on the lime kiln. Incineration of the 

9-12 
TABLE 9-5 

COMPARISON OF CONTROL TECHNIQUES ON ENERGY IMPACT 

FOR A 907 MEGAGRAMS PER DAY KRAFT PULP MILL 

Emissions lblday 

Fuel Electrical Total Energy -Fired Power Plant Supplying TRS 

lo9 Jlday (10 Btulday) Kwhlday lo9 J/day (10 Btulday) Part. NO, SO,, Control Technw 

The Electrical Energy a Reduction from 

5.7 (12.6) 40 (88) 68 (150) 650 (1440) 

Control Requ i remen t Requ i remen t Requirement 

Source Technique ,. L . __ 

Recovery Furnace 8LOb 0 (0) 14,400 52 (49 1 

Non-contact 

evaporator 1150 (1 090) 0 1150 (1090) 0 (0) 

Digester System Scrubbing 0 (0) 2,880 11 (10) 1.1 (2.5) 8 (18) 14 (30) 180 (400) 

Incineration 0 (0) 2,880 11 (10) 1.1 (2.5) 8 (18) 14 (30) 680 (1500) 

Mu1 tip1 e-effect Scrubbing 

Evaporator System Incineration 

Lime Kiln 

W 

A 

w 

Brown Stock Washer 

System 

Black Liquor Oxidation System 

d Smelt Dissolving 

Tank 

Condensate Stripper 

System 

150 (142) 

High Eff. Mud 150 (142) 

Washing 

Process Controls, 150 (142) High Eff. Mud 

Washing & Caustic 

Scrubbing 

Process Controls 

Process Controls 1 

Incineration 234G (22201 

Incineration 

Oxygen 0 (0) 

Fresh Water 0 (0) 

Incineration 0 (0) 

INCLUDED IN DIGESTER SECTION 420 (920) 

450 (1000) 

1,075' 154 (146) 0.5 (1.0) 3 (7) 5 (12) 270 (600) 

1,075' 154 (146) 0.5 (1.0) 3 (7) 5 (12) 340 (750) 

1,075' 154 (146) 0.5 (1.0) 3 (7) 5 (12) 350 (775) 

5,376 2360 (2240) 2.1 (4.7) 15 (33) 25 (56) 140 (300) 

INCLUDED IN WASHER SECTION 45 (100) 

20,000 80 (68) 8.0 (17.5) 55 (122) 95 (210) 45 (100) 

2,400 8 (8) 1.0 (2.1) 7 (15) 11 (25) 80 (175) 

840 3 (3) 0.3 (0.7) 2 (5) 4 (8) 910 (2000) 

6 6 Data are based n the new source performance standards for coal-fired power plants (Part. - 0.1 lb/10 Btu; NOx - 0.7 lb/10 Btu; 

SO2 - 1.2 lb/10 Btu). 

Requirements are for two-stage oxidation. 

Electrical requirement is for operating a condensate stripper to TRS from scrubbing water, if contaiminated condensate is used. 

Requirements are for a scrubbing system, if a scrubber is not already used to control particulate emissions 

8 a 
noncondensable gases (digester, multiple-effect evaporator, and condensate 

stripper)would not require additional fuel if the? are burned in the lime kiln 

as part of the primary air feed. 

Incineration of the vent gases from the brown stock washers and black 

liquor oxidation system would require an additional fuel consumption of 2340 

X lo9 joules/day (2,220 million Btu/day). 

9 It is estimated that an additional 150 X 10 joules/day (142 million Btu/day) 

of fuel (without consideration of extra heat losses) will be required when process 

controls (higher cold end temperatures and higher oxygen levels) are used to 

control TRS compounds from a lime kiln. 

the normal fuel consumption of a lime kiln. 

This is approximately five percent of 

The additional electrical energy needed for each of these control techniques is estimated to be between zero and 15,000 kilowatt-hours per day. 

Control System 1 would reauire about 23,500 kilowatt-hours per day of additional 

electrical energy. 

kilowatt-hours per day of additional electrical energy. 

kilowatt-hour per day would be required for each system if a condensate stripper 

and a scrubber for the smelt dissolving tank are needed. 

Control Systems 2 through 6 would require about 18,125 

An additional 350 

Each contro system would result in an additional fuel requirement of 150 

9 X 10 

which would resu t in an additional fuel requirement of 2482 X 10 joules/day 

(incineration of BLO and washer gases). 

electrical requirement in the order of 700 to 1400 kilowatt-hours per ton of 

product.' 

between one to three percent of the total mill electrical usage. 

jouleslday (for lime kiln controls) except for Control System No. 1, 

9 

A pulp and paper mill requires an 

Therefore, these control systems will result in an increase of 

9-14 
REFERENCES FOR CHAPTER 9 

1. Incineration of Malodorous Gases in Kraft Pulp Mills, Burgess, T. L., 

Cater, D. N., and McEachern, D. E. Pulp and Paper Magazine of Canada. 

Volume 75, Number 5. May 1974. 

2. Energy and Air Emissions in the Pulp and Paper Indust=. James E. Roberson, 

J. E. Sirrine Company. Greenville, South Carolina. 

9-1 5 

10. EMISSION GUIDELINES FOR EXISTING 

KRAFT PULP MILLS 

Various alternative control systems can be applied to existing kraft pulp 

mills as described in Chapter 6. This chapter will select a system which is 

judged to be the best for existing plants when costs are taken into account, 

and will specify emission limitations that reflect the application of such a 

system. Time requirements to incorporate control techniques for each affected 

facility are discussed in Section 6.3. 

the other control systems were not selected as best retrofit technology. 

10.1 GENERAL RATIONALE 

Section 10.3 will briefly discuss why 

The best retrofit control technologies for the reduction of TRS emissions, 

taking into account the cost of this control, correspond to alternative control 

system No. -4, as indicated in Table 6-2. 

for brown stock washers, lime kilns, and black liquor oxidation systems are 

less restrictive than those that have been proposed by EPA for new kraft pulp 

The recommended control technologies 

mills. The recommended control technologies for the recovery furnace, digesters, 

mu1 tiple effect evaporators, smelt dissolving tank, and condensate stripper 

are the same for both new and existing sources. 

considered in determining best retrofit control technology: 

The following factors were 

1. The degree of emission reduction achievable through the application 

of various demonstrated control technologies. 

2. The technical feasibility of applying the various demonstrated technologies to existing sources. 

existing recovery furnace was evaluated. 

In particular, more than one basic design of 

10-1 
3. The impact of the various control technologies on national energy 

consumption, water pollution, sol id waste disposal , and ambient air concentrations 

of TRS. 

4. The cost of adopting the emission guidelines. Control costs were 

estimated for each alternative control system for each retrofit model, taking 

into account the level of existing controls. 

Identification of the best demonstrated control technology for new mills 

was accomplished during the development of NSPS for the kraft pulp industry. 

A question that must be answered by this study is whether or not it is technically 

and economically feasible to apply this technology to existing sources. Where 

this is not feasible, best retrofit technology considering cost is identified. 

Evaluation of the technical problems and costs associated with a retrofit 

project is complicated by the lack of actual data for some sources. For example, 

only recently has an existing brown stock washer system and black liquor oxidation 

system been retrofitted for control of TRS. 

units have been installed with control systems. 

control systems was available for the other process facilities in existing mills. 

Retrofit models were developed (see Section 6.2) to evaluate the environmental and 

cost impacts of installing TRS controls on existing recovery furnaces, digesters, 

multiple-effect evaporators, lime kilns, brown stock washers, black liquor 

oxidation systems, smelt dissolving tanks, and condensate strippers. 

retrofit model approach presents the impacts on an entire kraft pulp mill of 

applying control technologies to individual sources of TRS. The major technical problem, aside from space limitations, foreseen for the average mill is 

the ability of existing furnaces to maintain good combustion for TRS control 

Also, no new black liquor oxidation 

Retrofit information on 

The 

10-2 
while burning the vent gases from the pulp washer and the black liquor oxidation system. 

Table 10-1 indicates the impact on annual TRS emissions from the kraft 

industry if best retrofit control technology, (i.e. alternative control system 

No. 4) was used. Adoption of best retrofit control technology would result in 

emission reductions ranging from 40 percent at typically controlled mills 

to 95 percent at uncontrolled mills. Total emissions from the industry would 

be reduced by about 81 percent, resulting in a national TRS reduct 

60,900 megagrams per year (67,150 tons per year). 

Adoption of best retrofit control technology will result in a 

reduction of 95 percent in ambient air concentrations at uncontrol 

on of about 

maximum 

ed mills. 

Emission reductions, and likewise control costs, will be less formills which 

have already installed some control systems. 

10.2 SELECTION OF BEST RETROFIT TECHNOLOGY AND EMISSION GUIDELINE 

10.2.1 Recovery Furnace System 

Emission Guideline - "Old Design" furnaces (i .e. , furnaces without membrane 

wall or welded wall construction, or emission-control designed air systems) : 

20 ppm of TRS as H2S (0.3 g/Kg ADP) on a dry gas basis and as a f2-hour average, 

corrected to 8 volume percent oxygen. 

- "New Design" furnaces (i.e. , furnaces with both membrane wall or welded 

wall construction and emission-control designed air systems): 

H2S (0.075 g/Kg ADP) on a dry gas basis and as a 12-hour average, corrected to 8 

volume percent oxygen. (A "New Design" furnace will have stated in its contract a 

TRS performance guarantee or that it was desianed with air pollution control as an 

objective. ) 

- 

5 ppm of TRS as 

Cross recovery furnaces (i.e., furnaces with green liquor sulfidities in 

excess of 28 percent - and liquor mixtures of more than 7 percent NSSC on an air dry 

ton basis): 

average, corrected to 8 volume percent oxygen. 

25 ppm of TRS as H2S (0.6 a/Kg ADP) on a dry gas basis and as a 12-hour 

10-3 
Table 10-1, BEST RETROFIT-CONTROL TECHNOLOGY AND IMPACT FOR INDIVIDUAL 

SOURCES IN THE EXISTING KRAFT PULP INDUSTRY 

Resultant TRS reduction 

at an average kraft Resultant national 

Best- Demonstrated TRS level mill (% of total TRS reduction 

Source control technique achievable mill emissions) (tons/yezr) 

Recovery furnace Process controls + 20 ppm*(Old Design) 44.2 

13.0 

BLO 

Digester system Incineration 5 PPm 

+ Paul ti pl e-effect Incineration 5 PPm I evaporator system 0 

P 

Lime ki 1 n Process controls 20 ppm** 

(inc. high eff. mud 

washing) 

.I Brown stock washer No control - 

system 

8.6 

11.9 

0 

36,500 

10,700. 

7,050 

9,800 

0 

Black liquor No control 

oxidation system 

- 0 0 

Smelt dissolving tank Fresh water 0 .OO84 g/kg BLS 3.7 3,100 

', Condensate stripping Incineration 5 PPm neg 

Total % reduction = 81.4 

system - 

neg . 

67,150 

*One percent af all twelve-hour TRS ayerages above the spectfied level aye not considered to be excess emlsslons. 

**Two percent of all twelve-hour TRS averages above 20 ppm are not considered to be excess em-issions. 
Discussion - The emission guidelines represent the levels that can be 

achieved by using a two-stage black liquor oxidation system together with 

good furnace operation. 

kraft recovery furnaces reflect the dependence of TRS emissions on the design 

of the furnace, which in turn depends on the age of the recovery furnace. 

the design of the furnace affects the TRS level that can be achieved, the 

reduction of TRS emissions from the direct contact evaporator necessary to 

reduce emissions to the level of the guidelines requires the use of high efficiency 

black liquor oxidation systems regardless of the design of the furnace. 

recovery furnaces constructed since 1965 are generally considered capable of 

achieving 5 ppm TRS because the furnace design is basically similar to furnaces 

presently being installed which can achieve 5 ppm TRS.’ 

The two specified levels of TRS emissions for straight 

While 

Most 

Approximately 40 percent 

of the existing recovery furnaces were constructed after 1965. 

which were constructed before 1965 generally do not have the appropriate design (i.e., 

membrane or welded wall construction and flexibility of air distribution) or 

instrumentation necessary for achieving 5 ppm. 

manufacturers ,2y3 however, these older furnaces are generally capable of 1 imi ting 

TRS emissions to 20 ppm if the furnace is properly operated, uses high efficiency 

black liquor oxidation, and is not operated at an excessive production rate. 

Recovery furnaces 

As confirmed by the two furnace 

As mentioned in Chapter 6, cross recovery liquors are somewhat different 

than straight kraft liquors. Consequently, TRS emissions from a cross recovery 

furnace are not controllable to the same degree as are those from straight 

kraft recovery furnaces. The reasons for this include higher sulfur-tosoda ratios and lower BTU value of the liquor fired. 

nique of using excess combustion air (high oxygen levels) to reduce TRS 

emissions is of limited utility because it reportedly results in a sticky 

Furthermore, the tech10-5 
dust which will foul the precipitator and render furnace operation difficult 

or impossible. Tests performed on a non-contact type cross-recovery furnace 

indicate that TRS emission levels of 25 ppm (12-houraverage) can be achieved 

from well controlled cross recovery furnaces.4 

Appendix B presents TRS emission data for straight kraft recovery furnaces 

and a cross recovery furnace. 

Retrofit annualized costs for installing a second stage of black liquor 

oxidation are about $240,000 for a 907 megagramslday (1,000 tons ADP/day) mill. 

Retrofit costs would 1,. double if a mill does not presently have a single 

stage of oxidation. Annualized costs, including capital charges, are estimated 

to be about $0.75 per ton ADP, or about 0.25 percent of the pulp price to install 

a second stage of black liquor oxidation. 

excess i ve. 

These costs are not considered 

It appears that approximately 18 recovery furnaces may not be able to 

achieve 20 ppm TRS because the furnace either does not have sufficient control 

for proper combustion or is operated at an excessive production rate and cannot 

supply sufficient oxygen to achieve good combustion. Studies have demonstrated 

that minimum TRS emissions are not achieved unless residual oxygen content of 

the flue gas is in the range of 2.5 to 4.5 percent. 

overloading of the furnace can exist regardless of the age of the furnace.) 

these furnaces are required to achieve the emission guideline, a new furnace 

would have to be installed (at an annualized cost of about $2.3 million for a 

500 tons per day furnace) to compensate for the cutback on production of an 

existing furnace. 

are at least 20 years old [this age is near the normal life (25 years) of a 

furnace, considering the compliance schedule undm Section 11 1 (d) ) and may be 

near rep1 acement. 

(Low oxygen levels due to 

If 

Many of the recovery furnaces that would have to be replaced 

10-6 
An alternative to replacing an old furnace would be to install a scrubber 

system, as mentioned in Section 6.11, which is capable of achieving less than 

20 ppm TRS. Installation 

and operation of such a system is expected to be a much less expensive alternative 

than replacement of the furnace. 

A scrubber system has been installed at one mill.5 

The emission guidelines for recovery furnaces are comparable to the emission 

levels which existing furnaces in Oregon and Washington are required to meet 

as of July, 1975 (17.5 ppm).6 The 17.5 ppm level represents the level that can 

be achieved by most existing recovery furnaces, and the 1983 Oregon and Washington 

level of 5 ppm represents the level achievable with the newer design furnaces 

and a1 lows time for the replacement of older furnaces (non-membrane wall construction). 

The estimated impact of adoption of the emission guideline on annual TRS 

emissions from recovery furnaces is 33,470 megagrams per year, an 85 percent 

reduction. 'The predicted maximum ambient air TRS concentration due to emissions 

from an uncontrolled recovery furnace would decrease by 96 to 99 percent with 

the recommended control technology. 

10.2.2 Digester System 

Emission Guideline - 5 parts per million of TRS as H2S on a dry gas basis 

and as a 12-hour average. 

Discussion - This TRS level is the same as that included in the new source 

performance standards for new digester systems. 

by incineration of the noncondensable gases. 

and several other states are required to incinerate the noncondensable gases 

from digester systems as of July, 1975.7 It is estimated that adoption of this 

control technology will result in a reduction of 99 percent in the uncontrolled 

TRS emitted from a digester system. 

The 5 ppm level is achievable 

Existing mills in Oregon, Washington, 

10-7 
The TRS level achievable by incineration of noncondensable aases from 

digester systems has been well-demonstrated as reported in Section 6.1.2. 

gases from the digester system can be handled in the lime kiln as Dart of the 

combustion air without requirinq extensive modification to the diaester system 

or lime kiln. 

is presently being accomplished by at least 60 mills. 

inciperation systems were retrofitted to the existing mills. 

The 

Incineration of the gases in lime kilns or in power boilers 

Nearly all of these 

Incineratim is so far the only control option capable of providing high efficiency 

TR3 reduction. 

would result from control by white liquor scrubbers (see Chapter 6). 

scrubbers are effective in controlling H2S and methyl mercaptan which comnrise 

only approximately 20 percent of the TRS emissions from digester systems. 

A thousand-fol d increase in emi ssi ons to approximately 7000 pDm 

These 

If the emission guide1 ines were increased moderately , incineration costs 

would not vary greatly. 

lime kiln is essentially fixed regardless of the selected emission level. 

existing kraft pulp mills incinerate these gases in the lime kiln and normal 

kiln operation will oxidize the TRS compounds to less than 5 ppm. 

The cost of collecting and burning the gases in the 

Most 

Retrofit annualized costs are estimated to range from about $65,000 to 

about $210,000 for a 454 megagram mill , or about $0.40 to $1.25/T ADP. The 

low value represents costs for piping only, while the high value represents 

costs for pipina, blow heat recovery system, and a seoarate incinerator. These 

costs are not considered excessive. 

The estimated impact of adoption of best retrofit contro 

annual TRS emissions from rlicester systems is sianificant, 11 

year or a 97 percent reduction from uncontrolled levels. 

techno1 ocly on 

800 meaarwams per 

10-8 
10.2.3 Multiple-Effect Evaporator System 

Emission Guideline - 5 parts per million of TRS as H2S on a dry gas basis 

and as a 12-hour average. 

Discussion - This TRS level is also the same as that in the new source 

performance standards for new multiple-effect evaporator systems. 

that achievement of this level will require a reduction of 98 percent of the TRS 

emitted from an uncontrolled mu1 tiple-effect evaporator system. Incineration 

is capable of achieving this level. Existing mills in Oregon, Washington, 

and several other States are required to incinerate these gases as of July, 1975. 

It is estimated 

8 

The TRS level achievable by incineration has been well-demonstrated as reported 

in the Standards Support and Environmental Impact Statement document for new 

kraft pulp mills. 

can easily be handled in the lime kiln as part of the combustion air without 

requiring extensive modifications to be. made to the multiple-effect evaporator 

The non-condensable gases from the multiple-effect evaporators 

system or the lime kiln. 

boilers is presently being accomplished by at least 59 mills. 

these incineration systems were retrofitted to existing mu1 tiple-effect evaporator systems. 

Incineration of these gases in lime kilns or in power 

The majority of 

Incineration is so far the only control option capable of providing high efficiency 

TRS reduction. 

(see Section 6.1.3) would be required to allow the use of white liquor scrubbers. 

scrubbers have only about a 90 percent TRS collection efficiency when used on the 

noncondensable gases from a multiple-effect evaporator system. 

A sixty-fold increase in TRS emissions to approximately 300 ppm 

These 

If the emission guidelines were increased moderately, incineration costs 

would not vary greatly. The control costs are mainly for collecting and transferring 

the gases to the control device whether incineration or scrubbing is practiced. 

10-9 
Most existing kraft pulp mills incinerate the gases in the lime kiln along with 

the digester gases, and normal lime kiln operations oxidize the gases to less 

than 5 ppm TRS. 

Retrofit costs for incineration of the noncondensable gases from the 

multiple-effect evaporators are included in the retrofit costs reported for 

the digester system (Section 10.2.2). 

Estimated impact of adoption of best retrofit technology on annual TRS 

emissions from multiple-effect evaporator systems is significant, 6,120 

megagrams (6,750 tons) per year or a 96 percent reduction. 

10.2.4 Lime Kiln 

Emission Guideline - 20 ppm of TRS as H2S on a dry gas basis and as a 

12-hour average, corrected to 10 volume percent oxygen. 

Discussion - The specified level reflects the dependence of TRS emissions 

on the operation of the kiln. 

level and cold-end temperature, and using water that does not contain dissolved 

sulfides in the particulate control scrubber. Existing mills will probably 

need to improve their lime mud washing efficiency (additional filtration and 

clarifier capacity) to reduce the sulfide level of mud fed to the kiln. 

This requires maintaining the proper oxygen 

Additional 

fan capacity may be necessary to obtain the required oxygen 'levels in existing 

kilns and thereby provide dppropriate control over the combustion. 

no apparent reasons why these changes cannot be made to existing kilns. 

installation of a condensate stripper may be required to remove sulfides from 

the condensate if it is used in the particulate control scrubber. Appendix B 

presents TRS emission data, which were obtained during the NSPS program, for 

several lime kilns that achieve this level. 

There are 

Furthermore,. 

10-10 
Retrofit annualized costs for additional fan capacity (to achieve higher 

oxygen levels) and instrumentation are about $55,000 for a 458 megagramslday 

(500 ton ADP/day) mi 11. 

capacity are about $90,000. 

incurred if a condensate stripper is needed to remove the sulfides from the 

scrubbing water. These annualized costs, including capital charges, are estimated 

to be about $0.90 per ton ADP if a condensate stripper is not needed and about 

$1.50 per ton ADP if one is needed. These costs are not considered excessive. 

Retrofit annualized costs for additional mud washing 

An additional $90,000 in retrofit annualized costs would be 

The impact of adoption of best demonstrated retrofit control technology 

on TRS emissions from kraft lime kilns is significant, an 84 percent reduction 

(9,800 tonslyear) from existing levels. Maximum ambient TRS concentration due 

to an uncontrolled lime kiln would be reduced by 83 percent. 

Lower TRS levels than the emission guideline are achievable as stated 

in Section 6.1.4 and as reflected in the proposed standard for new lime kilns 

(8 ppm TRS). 

scrubbing. 

The lower TRS level is achievable with the addition of caustic 

Many existing lime kilns are operating in excess of design capacity, 

and some of these kilns, even with improved mud washing efficiency, may not 

be able to achieve TRS levels significantly lower than 40 ppm because of the 

inability to supply sufficient oxygen for good combustion. 

between 20 and 33 lime kilns (corresponding to about 20 percent of the existing 

kilns) would have to be replaced or added in order to achieve 20 Dpm TRS by aDplyina 

the best retrofit control technology discussed above (see Chapter 8). 

costs for a new lime kiln are $3 million, and annualized costs are $510,000. 

It appears that 

Capital 

The lower TRS emission level of 8 ppm is not recommended as an emiss on guideline 

so that the number of kiln replacements is minimized. 

of those mills which cannot achieve 20 ppm from the lime kiln by applying process 

The higher level a so allows some 

10-1 1 
controls and improved mud washing to apply caustic scrubbing to achieve the guideline 

rather than replacing or adding a new lime kiln. 

pulp mill showed that levels of 40 to 50 ppm TRS could be reduced to a level 

less- than 20 ppm by using caustic additi~n.~ 

is technically achievable at existing mills and can be imposed if the location of 

the mill or lime kiln warrants additional controls. 

The results of trials conducted at one 

Nevertheless, the lower TRS level 

10.2.5 Brown Stock Washer System 

Emission Guideline - No emission guideline is recommended for existing 

brokn stock washer systems. 

Discussion - No TRS control is recommended due to the high costs associated 

with hooding and collecting the gases and the possible effect the gases may have 

on existing recovery furnace operation. 

Incineration of the vent gases is the emission control technique that could 

be used to reduce TRS emissions from brown stock washer systems. Burning 

these gases in an existing recovery furnace is considered by furnace manufacturers 

to be technologically feasible. 

been demonstrated on an existing furnace, and the TRS level that can be achieved 

from an existing furnace under these conditions has not been demonstrated. 

control costs for incineration, therefore, have been based on the use of a separate 

incinerator. 

possibly with enclosed hoods, and ductwork would be necessary to transfer the 

gases to the incinerator. 

at some mills if the recovery furnace was used.) 

separate incinerator would require retrofit annualized costs of about $900,000 

for a 454 meqaqram mill or about $5.50/T ADP. 

10 This control technique, however, has not yet 

The 

Incineration of the gases would require that the washer be hooded, 

(These gases would have to be ducted over 1500 feet 

Incineration of gases in a 

These costs are much more 

10-1 2 
a 

severe than retrofit costs for the other TRS sources and are considered to be 

excessive in comparison with control of the other sources of TRS and with the 

amount of TRS reduction achieved (about 1 percent of total mill TRS emissions). 

10.2.6 Black Liquor Oxidation System 

Emission Guideline - No emission guideline is recommended for existing 

black liquor oxidation systems. 

Discussion - No TRS control is recommended due to the expected cost impact 

on the industry if existing sources were required to meet TRS levels achievable 

for new systems. 

uncontrolled level ) than that considered demonstrated for new sources. 

There is no less stringent control method possible (except for the 

Achievable control technology involves incineration of the vent gases or 

the use of molecular oxygen instead of air to eliminate the vent gases. 

of controlling the low concentration/high volume gases from black liquor oxidation 

systems is considered more severe and excessive in comparison with controlling 

the largest sources of TRS at kraft mills (see Section 10.3). The control costs 

for incineration have been based on the use of a separate incinerator, since the 

effect of these oxygen-deficient gases on furnace combustion and thus TRS 

emissions from existing furnaces has not been determined. 

costs are estimated to be $230,000 for a 500 TPD kraft mill, or $1.50/T ADP. 

These costs are considered excessive in view of the amount of TRS reduction that 

would be achieved by incineration (about 0.4 percent of total mill TRS emissions). 

10.2.7 Condensate Stripping System 

The cost 

Retrofit annualized 

Emission Guideline - 5 parts per million of TRS as H2S on a dry gas basis 

and as a 12-hour average. 

10-13 
Discussion - This emission guideline is the same as that included in the 

new source performance standards for new condensate stripping systems. Only 

five existing mills have condensate strippers, and only one is not present 

incinerating the off-gases. Incineration of the off-gases is necessary to 

achieve this TRS level. 

Retrofit annualized costs based on combining the stripper off-gases w 

the noncondensable gas from the digesters and evaporators are estimated to 

Y 

th 

be 

about $6,500 for a 500-ton-per-day mill or about $0.05/T ADP. 

on the industry due t, control of this facility is expected to be negligible. 

The cost impact 

Use of a white liquor scrubber, the only other control technique used, 

would permit TRS emissions which are 100-fold higher than with incineration. 

These TRS levels from scrubbers could be highly odorous. 

10.2.8 Smelt Dissolving Tank 

Emission Guideline - 0.0084 g/kg BLS of TRS as H2S (approximately 8 ppm) , 

on a 12-hour average. 

Discussion - This emission guideline is also the same as that included in 

the new source performance standards for new smelt dissolving tanks. Achievement 

of this level would require the use of fresh water, or possibly weak wash liquor, 

in the particulate control device (scrubber) to ensure compliance. 

The control costa for achieving this level are not considered excessive. 

Adoption of this level is expected to result in an emission reduction of about 

2720 megagrams (3000 tons) per year of TRS. 

10.2.9 Excess Emissions 

Excess emissions are defined as emissions exceeding the numerical 

emission limit included in an emission guideline. Continuous emission 

monitoring, however, will identify all periods Gf excess emissions, including 

those which are not the result of improper operation and maintenance and 

19-14 
therefore are not to be considered as violations. Excess emissions due to 

start-ups shutdowns and malfunctions for example, are unavoidable or 

beyond the control of an owner or operator and cannot be attributed 

to improper operation and maintenance. 

result of some inherent variability or fluctuation within a process 

which influences emissions cannot be attributed to improper oDeration 

and maintenance, unless these fluctuations could be controlled by more 

carefully attending to those process operating parameters during 

routine operati on which have 1 i ttle effect on operati on of the process , 

but which may have a significant effect on emissions. 

Similarly, excess emissions as a 

To quantify the potential for excess emissions due to inherent 

variability in a process, continuous emission monitoring data are used 

whenever possible to calculate an excess emission allowance. 

kraft pulp mills, this allowance is defined as follows. 

calendar quarter is divided into discrete contiguous twelve-hour time 

periods, the excess emission allowance is expressed as the percentaqe of 

these time periods excess emissions may occur as the result of unavoidable 

vari abi 1 i ty within the kraft pulping process. 

allowance represents the potential for excess emissions under conditions 

of proper operation and maintenance, in the absence of start-ups 

2nd malfunctions, and is used as a guideline or screening mechanism for 

interpreting the data generated by the excess emission reporting requirements. 

The definitions of excess emissions for recovery furnaces and lime 

kilns are discussed below. 

For 

If a 

Thus, the excess emissions 

shutdowns , 

Recovery Furnace Systems - A pulp manufacturer submitted six months 

of TRS emission data from one of their new design recovery furnaces 

and equested that EPA consider the data in defining excess T!?S emissions 

from recovery furnace facilities. 

deve oping the data upon which the new source performance standard is 

The furnace was tested by EPA in 

1r)-15 
based. The submitted data, recorded by a continuous monitor, show that 

over the 6-month period, the percent of time that the TRS concentration 

exceeded 5 ppm during each month ranged from 0 to 4.9 percent and 

averaged about 1 percent in normal operation (including load changes). 

EPA has investigated the furnace operation and the monitoring system at 

this mill and believes that the data are a true indication of normal , 

well controlled operation for this furnace. 

For cross recovery furnaces similar excess emissions can be predicted. 

For old drsign recovery furnaces, no such continuous monitoring data are 

available. However, considering that the excess emissions a1 lowance 

must represent the potential for excess emissions due to inherent 

reliability in the process itself and that the stringency of the standard 

for new design furnaces is at least comparable to that for old design 

furnaces, it appears reasonable to use the same excess emissions 

allowance. Therefore, based on that information, an allowance of 1 

percent of the 12-hour averages has been given for excess TRS emissions 

above the guideline. 

Lime Kiln - Test data on a 4-hour basis (see Appendix B) were 

supplied by a mill (Lime Kiln P) that had retrofitted the lime kiln 

system with additional fan capacity and mud washing capacity. These 

data give an indication of the variations in the emission concentrations 

over a large number of four-hour periods. 

when the mill was maintaining good process controls (high cold end 

temperatures, high oxygen levels, and high mud solids contents) on the 

kiln, the four-hour average TRS concentrations exceeded 20 ppm for approximately 11 percent of the time.” However, during this same period the mud 

filter (belt filter) was inoperative for 0 percent of the time. However, 

process and emission monitoring data obta ned on Lime Kiln E (see Appendix 

B) show excess TRS emissions of 2 percent on a 4-hour average basis over 

The data show that for the period 

10-16 
the 8 ppm level with down t 

percent. 

From the comparison of 

the mud filter on Lime Kiln 

me on the mud filter (vacuum drum) of only 1 

those two sets of data, it was felt that had 

P been operating properly, as had that of 

Lime Kiln E, there would have been excess emissions only 2 percent of the 

time, instead of 11 percent, on a 4-hour average basis. 

averaging period, Lime Kiln E should have no excess emissions during normal 

operation.12 

Kiln P. 

With a 12-hour 

However, the data do not support this conclusion for Lime 

Therefore, it is felt that with a reliable mud filtering system 

and maintaining good process controls on the kiln, the 12-hour average 

TRS concentrations will exceed 20 ppm for no more than 2 percent of the 

time. 

is advised for excess TRS emissions above the guideline. 

10.3 SUMFIARY OF THE RATIONALE FOR SELECTING THE BEST RETROFIT CONTROL SYSTEM 

Hence, an allowance of a maximum 2 percent of the 12-hour averages 

The proposed TRS emission limits for new kraft pulp mills are technologically achievable at existing kraft pulp mills when the best control 

techniques discussed above are applied to each of the eight coniponent 

process operations. 

are considered excessive for some existing mills, in part because some 

techniques involve rep1 acement of recovery furnaces or 1 ime ki 1 ns. 

alternative control techniques which are effective but less costly are 

available for some process operations. Therefore, the cost of applying the 

various control techniques had a considerable influence on the selection of 

the recommended best retrofit control technology (alternative control 

system No. 4 for an entire kraft mill). 

However, the costs of applying the best control techniques 

Further, 

Control of the brown stock washer system and black liquor oxidation 

system (alternative control system No. 1) are not recommended because 

incineration of these vent gases in a separate incinerator would result 

10-17 
a 

in excessive operating costs and fuel requirements in comparison to the 

TRS reduction achieved by the control technique. Incineration of these 

gases in an existing recovery furnace is not presently considered to be 

demonstrated retrofit technology. 

to handle these gases has demonstrated the ability to burn these gases 

and still maintain proper combustion for controlling TRS emissions from 

No existing recovery furnace not designed 

the furnace itself. 

The emi ssi on gui del i ne recomnended for 

20 ppm for "old design" furnaces, 5 ppm for 

ppm for cross recov6,y furnaces. The older 

achieving 5 ppm and a large number of exist 

existing recovery furnaces is 

"new design" furnaces, and 25 

furnaces are not capable of 

ng furnaces would most likely 

have to be replaced if such a level was required. 

required for each type of furnace to meet the recommended levels is 

two-stage black liquor oxidation and process controls. 

The control technique 

Incineration of the noncondensable gases from the digesters, multipleeffect evaporators, or condensate strippers in the lime kiln has been 

demonstrated at many existing mills. Therefore, since the control costs 

are not excessive, the emission guideline recommended is the same as the 

new source perfonnance standard (5 ppm TRS) for new kraft pulp mills, 

An emission guideline of 20 ppm TRS is recommended for existing 

lime kilns. 

20 ppm can be achieved with proper kiln operation and sufficient mud 

washing efficiency. 

be necessary for most existing kilns. Lower TRS levels are achievable, 

but several additional lime kilns would have to be replaced or added in 

order to achieve a level of 8 ppm TRS. 

Emission data obtained during the NSPS program show that 

Larger fans and additional mud washing capacity wi 11 

The emission guideline recomnended for snl?lt aissolving tanks will 

probably prevent the use of contaminated condensate in the tank and the 

10-18 
particulate control device, if one is used. 

already for controlling particulates, one may have to be installed to 

reduce TRS emissions from an existing smelt dissolving tank to the 

recommended gui del i ne. 

If a scrubber is not used 

The best retrofit technologies (alternative control system No. 4) 

will produce a large reduction in national TRS emissions (67,15r3 tons/year) 

and in ambient TRS concentrations around existing mills. 

10.4 SELECTION OF THE FORMAT OF THE EMISSION GUIDELINES 

Standards for kraft pulp mills could be expressed in terms of either 

mass emissions per unit of production or a concentration of pollutant in 

the effluent gases. The most common format now used by the industry and 

state control agencies is pounds of pollutant per ton of air-dried 

unbleached pulp produced (lb/T ADP). This format offers the advantage of 

preventing circumvention of the standards by the addition of dilution air 

or the use of excessive quantities of air in process operations. 

principal disadvantage is that a control agency cannot readily or 

accurately measure the pulp production over the short term. 

storage capacity of the mill, the recovery furnace, smelt dissolving tank, 

1 ime ki In, condensate strippers, bl ack 1 iquor oxidation tanks, and 

The 

Due to 

mal tiple-effect evaporators can be operating on accumulated inventories 

when the digesters are off-stream (nb pulp production). Similarly, the 

above facilities can be operating below capacity even though the pulp 

production may be at design rates. 

Concentration units are used as the format for the emissi'on guidelines 

for the digesters, the mu1 tip1 e-effect evaporators 

the lime kiln, and the condensate stripping system. 

selection of this format are outlined below: 

the recovery furnace, 

The reasons for the 

a. Concentration units can be corrected for excess oxygen in the lime 

10-1 9 
kiln and recovery furnace exhaust streams, precluding circumvention of the 

standards by dilution. 

b. The reference test method for TRS produces data in concentration 

units. 

compliance for the affected facilities. 

No conversion factors are therefore requi red in determining 

c. Average concentrations rather than instantaneous concentrations 

are proposed to allow for fluctuations in emissions which occur even during 

peri ods of normal operati on. 

d. Commercially available continuous monitors that may be used to 

measure emissions from these facilities indicate concentration directly. 

A direct indication of performance of the control systems would be available, 

and therefore the operator would be aware of excess emissions that require 

corrective action. 

The emission guideline for smelt dissolving tanks is expressed in 

grams per kilogram BLS (g/kg BLS). 

correcting for excess oxygen because the exhaust stream discharged from 

the smelt dissolving tank is mostly ambient air. 

Dilution cannot be prevented by 

10.5 RECO!+IENDED MONITORING REQUIREMENTS 

Monitoring requirements are necessary to ensure proper operation 

and maintenance of the affected facility and its associated control system. 

The volume concentration of TRS emissions can be monitored by use of 

measurement systems (see Chapter 7). 

trol device parameters that are appropriate indicators of concentratian of 

TRS emissions from recovery furnace systems and lime kilns, it is 

recommended that TRS continuous monitors be required for recovery furnaces 

and lime kilns; however, it is also recommended that those requirements 

not become effective until promulgation of performance specifications 

for TRS monitors. 

Since there are no process or conio-za 
TRS concentrations in the effluent gases from an incinerator that 

controls TRS emissions (from the digesters, multiple-effect evaporators, 

and/or condensate strippers) can be measured by a continuous monitoring 

system. An effective alternative method of monitoring TRS emissions from 

an incinerator is continuous measuring and recording of the fire box 

temperature of 540°C (1OOOOF) and operation at a residence time of at least 

one-half second in the fire box. 

residence time that will not be reduced if the incinerator is not operated 

above its design capacity. 

and recorded. 

the guidelines are incinerated in the recovery furnace or the lime kiln, the 

TRS monitoring system on the furnace or the lime kiln will serve to monitor 

the sources that are being incinerated. 

Incinerators are designed for a particular 

The fire box temperature can be readily measured 

If noncondensable gases from facilities that are covered by 

Since the guideline for smelt dissolving tanks is expressed in a format 

of pollutant mass per unit of feed to the furnace, the gas flow rate and 

the feed rate to the furnace would have to be measured simultaneously 

to reduce the TRS concentrations measured by the monitor to units of the 

The inaccuracies involved in continuously measuring 

sufficiently large 

t dissolving tank 

recommended guideline. 

emissions from the 

that no direct mon 

is recommended. 

s me 

tor 

t dissolving tank are felt to be 

ng of TRS emissions from the sme 

10-2 1 
References for Chapter 10 

1. Letter from J. W. Kesner of Babcock and Wilcox Company to James Eddinger 

of EPA, dated May 27, 1975. 

2. Presentation given by Julius Gomni of Combustion Engineering at the 

NAPCTAC meeting in Raleigh, North Carolina, on March 3, 1977. 

3. Op. cit. , Reference 1. 

4. A Report on the Study of TRS Emissions from a NSSC - Kraft Recovery 

Boiler, Container Corporation of America, March 9, 1977. 

5. Considerations in the Design for TRS and Particulate Recovery from 

Effluents of Kraft Recovery Furnaces, Teller, A. J., and Amberg, h. r. , Preprint , TAPPI Environmental Conference, Hay, 1975. 

6. Analysis of Final State Implementation Plans Rules and Regulations, 

prepared by the MITRE Corporation for the U.S. Environmental Protection 

Agency, Contract No. 68-02-0248, July, 1972. 

7. Op. cit., Reference 6. 

8. Op. cit. , Reference 6. 

9. Telephone conversation between Larry Weeks of Hoerner-Wal dorf Corporation 

and James Eddinger of EPA on September 6, 1977. 

10. Op. cit. , Reference 1. 

11. Letter from Richard C. Wigger of Champion International Corporation to 

Don R. Goodwin of EPA, dated June 13, 1977. 

12. Standard Support and Environmental Impact Statement, Volume 11: Promulgated 

Standards of Performance for Kraft Pulp Mills, EPA-450/2c76-014b, December, 

1977. 

10-22 
APPENDIX A 

SUMMARY OF KRAFT MILLS 

IN THE UNITED STATES 

A- 1 
i 

--~ Company 

A1 abamd 

Allied Paper 

American Can 

Champion 

Container Corp. 

Gerogia Kraft 

Gulf States 

Gulf States 

Hainnermill 

I.P. 

Kimberly-C1 ark 

MacMi 11 an 

Bloedel 

Scott 

Union Camp 

Southwest Forest 

Arizona 

Arkansas 

Georgia-Paci fic 

Great Northern 

Green Bay 

I.P. 

I.P. 

Weyerhaeuser 

Locat ion I_ - - -. 

Jackson 

Bul ter 

Court1 and 

Brewton 

Mahrt 

Oempo 1 i s 

Tuscaloosa 

Selma 

Mobi 1 e 

Coosa Pines 

Plne Hill 

Mobile 

Mo n t gome ry 

Snowflake 

Crossett 

Ashdown 

Morri 1 ton 

Camden 

Pine Bluff 

Pine Bluff 

Mill 

Size 

Avp . Kraft 

Prod. 

(Kraft 

(Cap.) 

-..:e. .. 

500 

( 408 ) 

930 

500 

(500) 

900 

(850) 

1000 

(400) 

500 

( 500 1 

1300 

(1200) 

585 

(600) 

1000 

(975) 

(900) 

';;I 

(g) 

1400 

(1400) 

870 

(930) 

600 

(600) 

1250 

400 

750 

(750) 

1220 

(1 300) 

200 

(200) 

Recovery Furnace control3 TRS , 

No. of Rating Year TechUnits Manuf. tpd nique - - - Instal. - ... . 

. 2 

3 

1 

2 

1 

1 

2 

1 

2 

2 

1 

4 

1 

2 

3 

1 

2 

3 

2 

1 

' CE 

BkW 

B6 W 

Bk W 

BkY 

BkW 

BkW 

BkW 

B6W 

CE 

CE 

BkW 

CE 

BLW 

CE 

CE 

CE 

BkW 

BkW 

BkW 

CE 

566 post-1965 BLO 

350 post-1965 

1959.1 956 

390(each) 1965 BLO 

600 1968 BLO 

390 1962 BLO 

600 1969 Low Odor 

900 1965 

330 1955 BLO 

175 1947 BLO 

250 1941 (oxygen) 450 BLO 

7 00 1970 BLO 

BLO 

900 post-1965 

932 post-1965 BLO 

450;300 pre 1965 BLO 

700 pre 1965 BLO 

aoo 

250 1960 

500 1969 

2 006 5 00 

850 

540 

665 

250 

500 

2-275 

1100 

390 

165 

pre 1965 BLO 

pre 1965 

PO s t - 1 965 

post -1 965 

1965 

1966 

1946 

1966 

1959 

pre 1965 

Leve 1' 

#/T ADP 

0.5 

0.5 

0.11 

0.5 

0.5 

0.5 

0.5 

0.5 

0.5 

0.5 

0.E 

0.5 

0.5 

15.0 

0.6 

15.0 

15.0 

15.0 

15.0 

15.0 

i iinc - inciaeration 

B - Batch 

BLO - Black Liquor Oxidation 

3C - Continuous 

A-2 
a 

nits 

1 

2 

1 

2 

1 

1 

2 

1 

2 

1 

4 

1 

2 

2 

1 

1 

1 

Lime Kiln 

Size TRS 

>.of Tons (Ca0)Level 

Per Day #lTADP127 

157 

each 

181 

123 

120 

130 

75 

125 

225 

1400 

(total) 

174 

400 

117 

150 

0.8 

0.8 

0.05 

0.8 

1 0.8 

0.8 

o.a 

0.2 

"0. 

4 

6 

1 

8 

1 

1 

8 

4 

6 

1 

1 

13 

1 

6 

11 

4 

2 

2 

3 

Type' Tech- 

(Size) 

Batch 

B 

C 

B 

C 

C 

B 

(495) B 

( 600 

B 

C 

(250) C 

(925) 

B (910) 

C (500) 

C 

(500 tpd 1 

(400 tpd 1 

1870 I 

B 

E 

(1276) 

8 

(4iO) 

C 

B 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Inc. 

Leve l4 

#/T ADP 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

1.5 

0.02 

1.5 

1.5 

0.02 

1.5 

1.5 

No. 

1 

2 

1 

2 

1 

1 

2 

1 

1 

4 

1 

2 

4 

1 

1 

1 

Mu 1 t i p le-e f f ec t 

Evaporator 

Control TRS 

Tech- Level' 

nique-. - T(T ADP 

Inc. ' 0.02 

inc. 0.02 

inc. 0.02 

inc. 0.02 

inc. 0.02 

inc. 0.02 

scrub. 

inc. 

Inc. 

inc. 

inc. 

inc. 

inc. 

Inc. 

o .oa 

0.02 

0.02 

0.02 

0.02 

0.92 

0.32 

1 .o 

0.02 

1 .o 

1 .o 

1 .o 

100 

1 .o 

Brown Stock !dasher TRS 

Capacity gasher ~evel' 

No. - lWTPD Stazes #/TADP 

1 3 0.3 

2 3 

4 

1 2 

1 3 

2 300 3 

475 4 

1 600 3 

3 

1 3 

Uncontrolled figures given are average uncontrolled figures for the industry unless actual level knwn, controlled levels 

given are actual flgures when known otherwise state standard is given. 

state standard a 1 or actual level known a level of .1 BIT (70 ppm) is assu e!,,aec;"p:;i;: table showlrg the corr'espondlnq einfss~on rate in terms of pp6 and g/Kg AD? 1s presented at the en! 

Furnaces controlled with BLO but foryhich no 

A- 3 
Mill 

Size 

Avg . Kraft 

1: Prod. 

(Kraft) 

(Cap.) 

Company Locat ion t pd 

Laii- Crwn Slmpson Fa f rha ven 550 

fornia (550) 

'Fi breboard 

Louislana-Pac. 

Simpson Lee 

Florida Alton Box 

Container Corp. 

-Hudson P & P 

I. P. 

Proctor 1 Gamble 

St. Joe 

St. Regis 

St. Regis 

Georgia Continental Can 

Continental Can 

Brunswi ck 

Georgia Kraft 

Georgia Kraft 

Gi lman 

Great Northern 

Interstate 

Itt Rayonier 

Antioch 

Samoa 

AnderSW 

Jacksonvi 1 le 

Fernandine Beach 

Palatda 

Panama City 

Fo 1 ey 

Part St. Joe 

Jacksonvf 1 le 

Pensacola 

Augusta 

Port b!entworth 

Brunswi ck 

Krannert 

flacon 

St. Mary 

Cedar Springs 

Riceboro 

Jesup 

'8907 

600 

(700) 

150 

(160) 

675 

(650) 

1500 

(1 700) 

950- 

(950) 

1400 

(1400) 

900 

1300 

(1 300) 

1350 

(1400) 

( 920 

800 

(800) 

(900) 

625 

( 600 

1550 

(1 550) 

1550 

(1550) 

900 

1100 

1780 

(1 700) 

525 

(550) 

1200 

(1 250) 

( 900 1 

(1000) 

Recovery Furnace control3 TRS 

No. of Rating Year Tech- Level 

Units Hanuf. tpd Instal. nique +i/T MP 

1 $hh' 800 1964 BLO 0.5 

2 

2 

2 

1 

2 

3 

2 

3 

3 

3 

2 

2 

2 

2 

3 

2 

3 

2 

1 

3 

BIW 

CE 

BIW 

CE 

Rkw 

B8L' 

CF 

CE 

BLY 

CF 

CE 

CF 

PRW 

B1W 

CE 

B1U 

CF 

CE 

CE 

BhV 

tE 

RhW 

RhIJ 

BW 

TE 

rF 

400 1959 BLO 0.6 

350(each)pre 1965 BLO 0.5 

150 1962 EL0 6.5 

300 1973 Low Odor 

750 DOSt-1965 BLU 0.5 

1000 1967 Low Odor 0.15 

300 1955 PLO(0xvaen) 

250(each)195081954 ~ . 

900( each )pos t-1965 RLn 

41 31550 1952L1956 

500 ore 1965 

2336300 ore 1965 

300&383 ore-1965 

800(each) 1973 Low ndor 

400( each)l95961964 BL0 

1200 DOS~-1965 

1060 DOSt-1965 

350(each) 

1100 1970 Low Odor 

450 ore 1965 EL0 

3001550 pre 1965 

300 pre 1965 

500 1968 BLO 

2-275 ore 1965 

500 DOSt-1965 

665 ore 1965 Lou Odor 

1000 1072 Low Odor 

450 1065 

1100 . 1970 Lor Odor 

A658359 pre 1965 RLn 

0.5 I 

0.5 

0.5 

0.5 

0.5 

0.15 

0.6 

15.0 

0.5 

15.0 

15.0 

15.0 

0.5 

15.0 

0.6 

A-4 
t 

i t 2 

b t 

t 

E 

I 

I 

0 

f.0 E 

f.0 E L 

01 

0'1 

80'0 

I 

0'1 

20'0 

1. 

0'1 

0'1 

80'0 

20'0 

20'0 

L 

2 

2 

t 

0 

2 

2 

0 

E 

E 

E 

E 

t 

2 

S'l 3 

20'0 .'UL E 

8 

(005) 3' 

(ooft) 8 

8 

(0001) 

8 

3 

S'L 8 

(OOL) 

5' 1 8 

92 

9 

t 

L 

01 

EL 

8 

tl 

Ll 

6 

2 

81 

21 

1 

01 

61 

EL 

L 

L 

9 

1 

1 

1 D 

2'0 

8'0 

8'0 

50'0 

21'0 

SO'O 

E 

1 

2 

L 

1 

E 

E 

L 

1 

1 

E 

E 

E 

E 

E 

2 

2 

L 

1 

2 
Mill 

Size 

I' Avg . Kraft 

Prod. 

(Kraft) 

(Cap. 1 

Compaqy Location tPd 

- 

Georgia 

Owens-Illinois 

Union Camp 

Potlatch 

Idaho 

Kentucky 

Western Kraft 

Wes tvaco 

Boise Cascade 

Boise Cascade 

Continental Carl 

Crown Zellerbach 

Crown Zellerbach 

Georgia-Paci fic 

I.P. 

I.P. 

Olin 

Pineville 

Loui si ana 

Western Kraft 

.Biamnd Int. 

Matrle 

Georgia-Pacific 

I.P. 

Lincoln 

Val dos ta 950 

Savannah 2600 

(2550) 

Lewis ton 850 

(900) 

Hawesvi 1 1 e 300 

(320) 

Wick1 i ffe '600' 

(600) 

(1050) 

(325) 

(1400) 

DeRidder 1030 

El i zabeth 300 

Hodge 1400 

Bogal vsa '1 340' 

(1 350) St. Francisville 500 

(500) 

Port Hudson 530 

( 640 1 

Bustrop 1100 

Springhill 1000 

1650 

West Monroe 1125 

(1150) 

Pinevi 1 le 800 

(750) 

Campti 450 

Old Town 350 

Woodland 

Lincoln '340. 

(400) 

Recovery Furnace control3 TRS 

No. of Rating 'fear Tech- ~e~~l 

Units Manuf. tpd Insta. nique #/T ADP 

- 

3 

6 

4 

2 

1 

1 

1 

2 

2 

1 

2 

2 

4 

2 

1 

1 

1 

2 

2 

1 

CE 

CE 

CE 

Ba(W 

B6W 

CE 

B6W 

B6W 

B6 W 

CE 

CE 

B6W 

B6 W 

CE 

CE 

B&W 

CE 

B6 W 

B8 W 

CE 

Baw 

Baw 

MY 

Baw 

BELW 

Baw 

CE 

B&W 

3506250 pre-196; BLO 2.1 

1350 post-1965 EL0 2.1 

p re - 1 965 

300 1954 BLO 

400 1970 Low Odor 

6 

1508300 pre-1965 BLO 0.5 

225 1968 BLO 0.15 

300 1974 

833 post-1965 BLO 0.5 

1000 1968 BLO 0.6 

BLO 2.1 

300 1955 BLO 2.1 

800 1963 BLO 2.1 

350 pre-1965 

600 1963 EL0 2.1 

690 1965 BLO 0.6 

1233 post-1965 

1000 Dost-1965 

300 pre-1965 BLO 2.1 

1100 1966 

2-700;500 1973:66;62 BLO 0.6 

350 pre-1965. 

450 1963 BLO 2.1 

800 1974 Low Odor 

833 pre-1965 BLO 2.1 

420 1972 Low Odor C.15 

590 1969 Low Odor 0.15 

350(each) 1963 EL0 0.5 

800 1974 Low Odor 0.15 

600 pre-1965 BLO ' 

386 1970 Low Odor 0.15 

A-6 
Lime Kilns 

).of Tons (CaG) Level 

Tits Per Oay 4/T ADF 

Size TRS 

I 

3 

3 

1 

1 

1 

1 

2 

1 

1 

1 

1 

1 

1 

,. 0.8 

525 0.8 

400 0.2 

0.2 

0 

80 

60 0.05 

Io 

! 

75 I 

I 

471 

150 

200 

200 

I 

0.2 

01 

150 0.8 

0.05 

100 01 

1: 

1 

4 

No. (Size) nique iiir t\DP 

Digester Control 

Type Tech- Level 

9,B ! 1.5 

34 B tP%) 1.5 

11, 6 (120) inc. 0.02 

1 C (600) 

1 C 

3 B inc. 0.02 

1 C inc. 0.02 

7 B 1.5 

(320) 

(600) 

6 B 1.5 

3 C inc. 

2 C (250) 1 C 

0.02 (300) 

(1650) 34 B (1250) 1.5 

inc. 0.02 

1 C inc. 0.02 

2 C inc. 0.02 (660) 

1.5 

4 C inc. 0.02 

21c inc. 0.02 

(1 290 1 

1 (840) 

I 

,I=. 0.02 i1 IC 

!c 

' (600) 

C ' (600) 

C 

(400) 

inc. 

inc. 

inc. 

0.02 

0.02 

0.02 

Mu 1 t i p le -e f f e c t. 

Evaporator I 

Control TRS 1, 

Tech- Level 

No. nique ji/T ADP 

3 1 .o 

6 1 .o 

4 inc. 0.02 

1 

1 

1 

1 

2 

4 

1 

2 

1 

1 

1 

inc. 0.02 

inc. 0.02 

1 .o 

1 .o 

inc. 0-02 

1 .o 

inc. 0.02 

inc. 0.02 

1 .n 

1 .o 

inc. 0.02 

inc. 0.02 

0.0 

inc. 0.0 

inc. 0.0 

inc. . 0.0 

Brown Stock IJasher TRS 

Capacity Washer Level 

D. ADTPD Stages #/T ADP 

3 4 

1 3 

1 2 

1 

4' 

1 2 

4 

2 2 

1 4 

0.3 

0.3 

0.3 

0.3 

0.3 

1 

1 

1 

1 

1 

! 

1 

1 

1 

1 

1 

1 

1 

6.02 

0.3 

A- 7 
Mill 

Size 

1: Avg . Kraft 

Prod. 

(Kraft) 

(Cap. ) 

Company Locat ion tPd - Ma? ne 

Oxford 

S. 0. Warren 

Maryland 

Mi chi gan 

Wes tvaco 

Mead 

Scott 

Minnesota 

Boise Cascade 

Pot1 a tch 

M4s s i s s i ppi 

I.P. 

I.P. 

I.P. 

St. Regis 

Hoe rne r - Wa 1 do rf 

Montana 

New 

Hamps h i re 

N. York 

Brown 

I.P. 

N. Carol i na 

Champi on 

Federal 

Hoerner-Waldorf 

Weyerhaeuser 

Weyerhaeuser I 

Rwnford 

Wes tbrook 

Luke 

Escanaba 

Mus kegon 

Int'l Falls 

Cloquet 

Moss Point 

Natchez 

Vicksburg 

Monticel lo 

Missoula 

Berl in-Garham 

Ti conderoga 

Canton 

Ri ege 1 woad 

Roanoke Rapids 

New Bern 

Plymouth 

550 

(560) 

270 

( 300 

71 9 

(647 1 

600 

(600) 

240 

(225) 

320 

(350) 

400 

(330) 

71 5 

1000 

(1000) 

1200 

(1200) 

1620 

(1 650) 

1150 

(1200) 

750 

(750) 

5 90 

(460) 

1360 

(1 360) 

1100 

(1 050) 

950 

(950) 

640 

(625) 

1350 

( I 500) 

... 

3 

4 Recovery Furnace Control 

io. of & Rating Year Tech- Level 

hits Manuf. tpd Instal. nique P/TADP 

2 

1 

1 

1 

1 

2 

1 

2 

3 

1 

2 

2 

2 

1 

2 

3 

2 

1 

2 

CE 300&200 pre-1965 BLO 0.5 

BLW 250 1962 BLO 0.5 

CE 1150 post-1965 BLO 0.6 

: BbW 800 1969 Low Odor 0.15 

8 CE 240 pre-1965 BLO 2.1 

CE 150 pre-1965 0.15 

BBW 550 1973 

BBW 400 1971 Low Odor 

CE 330 pre-1965 BLO 2.1 

CE 900 post-1965 2.1 

BBW 6006250 1963B1954 

B&W 1000 1965 BLO 2.1 

CE 800(each)post-1965 BLO 0.6 

523 post-1965 

B&W 1000 1970 Low Odor 0.5 

500 1965 Low Odor 

BB W 467 1965 BLO 2.1 

CE 225 pre-1965 

B&W 5 00 1968 Low Odor 0.15 

BBW 900(each)1)70&196? 2.1 

CE 700 OS t - 1965 15.0 

2-350 . we-1965 

. BIW 709 1972 Low Odor 15.0 

CE 500 pre-1965 

CE 800 post-1965low Odor 0.15 

CE 1500 post-1965Low Odor 0.15 

-400 pre-1965 

A-8 
Lime Kiln 

Size TRS 

No.of Tons (CaO) Level 

Units Per Day $/T AD1 

1 

1 

1 

1 

1 

1 

3 

2 

I 

2 

2 

1 

1 

3 

120 

90 

220 

70( F1 UOsol ids) 

100 

410 

300 

300 

280 

: 00 

225 

31 5 

0.8 

0.8 

0.8 

0.05 

0.05 

0.05 

0.8 

0.05 

0.05 

0.05 

0.2 

0.8 

G.8 

0.05 

0.8 

1 

#' 

1 

4 

130. (Size) niqoe #IT ADP 

Digester Control 

Type Tech- Level 

6 

7 

10 

6 

1 

5 

8 

2 

2 

3. 

8 

9 

1 

18 

11 

11 

7 

231 

I inc; i 0.02 

inc. j 0.02 

inc. ' 0.02 

inc. 0.02 

inc. 0.02 

1.5 

1.5 

inc. I 0.02 

inc. 0.02 

inc. 0.02 

inc. 0.02 

inc. 0.02 

inc. 0.02 

L.K 

I 

inc. 0.02 

1.5 

1.5 

B 1.5 

B inc. 0.02 

B inc. 1.5 

(1 000) 

(800) 

(1 500) 

1 

1 

1 

1 

1 

1 

2 

4 

2 

3 

3 

2 

1 

5 

Mult iple-e f fec t . Evaporator ,'. 

Control TRS 

Tear- Level 

No. niqoes 4/T ADP 

inc. . 0.02 

inc. 1 0.02 

inc. " 0.02 

inc. 

inc. 

iw. 

iic. 

inc. 

inc. 

inc. 

inc. 

scrub 

inc. 

inc. 

0.02 

0.02 

1 .o 

1 .o 

0.02 

0.02 

0.02 

0.02 

0.02 

1 .o 

0.02 

0.08 

1 .o 

1 .o 

0.02 

3.1 

Brown Stock !dasher TRS , 

Capacity !Jasher Level+ 

No. ADTPD Stages i!/T ADP 

2 4 0.3 

1 3 

1 3 

1 3 

2 3 

3 

5 3 

1 2 0.02 

3 3 0.3 

A- 9 
Mill 

Size 

Avg.' 

Kraft 

Prod. 

(Cap.) 

i: (Kraft) 

Company Location tPd 

Ohio 

Grfcf 

Mead 

Oklahoma 

lleyerhaeuser 

Oregon 

American Can 

Boise Cascade 

Crown Z 

Georgie-Paci fic 

I.P. 

Western Kraft 

lleyerhaauser 

Appleton 

P.H. Glatfelter 

Penna. 

Penntech 

Mass 

Chi 1 

Val1 

1 on 

icothe 

ant 

Hal sey 

St. hslens 

C1 a tskmi e 

Toledo 

Card i ner 

A1 bany 

Springfield 

Roarinq Springs 

Spring Grove 

Johnsonburg 

5. Carolina 

Bowa ter Catawba 

I.P. Georgetown 

5. Carolina Florence 

lles tvaco Charleston 

(200) 

600 

(540) 

1300 

( 1300) 

300 

(;;I 

(1150) 

690 

1075 

(1075) 

600 

500 

1150 

( 1050) 

180 

(180) 

500 

(500) 

190 

(130) 

(916 j 

(545) 

(550) 

940 

(940) 

1830 

(1 750) 

660 

(675) 

2occ 

(1939) 

Recovery Furnace: control3 TRS 

No. of Ratin.: Year Tech- Level 

Units Yanuf. tpd I.iSta1. nique Q/T ADP - 

4 

2 

1 

1 

2 

1 

3 

2 

2 

2 

2 

2 

1 

1 

2 

2 

2 

4 

CE 

CE 

EhW 

BhW 

CE 

BLW 

CE 

BLW 

CE 

BLW 

CE 

BhW 

CE 

BLW 

CE 

MW 

B&W 

B&W 

CE 

66W 

366 pre-1965 BLO 

175 PW-1965 

15.0 

2.1 

1500 post-1965 Low Odor 0.1: 

400 1967 Low Odor 

450 1966 BLO 

7017 1975 Low Odor 

800 1964 BLO 

350(each)l -post1965 BLO 

2-pre1965 

420 1972 Low Odor 

420 pre-1965 BLO 

600 1969 Low Odor 

165 1965 

800(each)pre-1965 BLO 

post-1 965 

122 1960 

83 1950 

40061 50 pre-1965 BLO 

748 1969 Low Odor 

160 pre-1965 BLO 

600 1964 BLO 

450 1957 

900(each) 1966 BLO 

1963 

410 1962 

1000 1972 Low Odor 

1000 ore-1965 BLO 

360 ' 1955 

250 1948 

250 1945 

3.03 

0.3 e:$: 

0.1: 

< 0.5 

0.1: 

0.15 

15.0 

2.1 : 

I 

2.1 i 

2.1 : 

! 

0.5 ' 

I 

::i5 I 

i 

A-10 
Lime Kilns 

Size TRS 

.of Tons (CaO) Level 

its Per Day #/TUP 

TRS , 

Capacity !;asher LevelNo. ADTPD Stages a:/T ADP 

Brown Stock Washer 

-- - ---- 

! 0.8 

250 0.8 

0.8 

0.15 

0.2 

250 0.05 

260 0.05 

0.05 

0.2 

0;l 

0.8 

I 

, 0.05 

luo01 id) 

2 50 0.8 

1 0.8 

0.8 

1 150 0.8 

4 665 0.8 

a 

3 

2 

3 

2 

2 

11 

1 

6 

7 

1 

5- 

a 

16 

6 

5 

15 

1 

C inc. 

(1000) 

(500) 

(100) 

C inc. 

inc. (3io) 

C 

C inc. 

(916) 

B (650) inc. 

C (115) 

inc. 

B inc. 

5 380 inc. 

c 177oj 

B 

B (285) 

C (250) 

B 

(170) 

B 

(940) 

B 

(625) 

B (1800) inc. 

C (700) 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

1.5 

1.5 

1.5 

1.5 

1.5 

1.5 

0.02 

?tu 1 t ip 1 e -e f f ec t 

Evaporator 

Control Tks 

Tech- Level 

:qo. nique UP 

2 

1 

1 

2 

1 

3 

1 

2 

1 

2 

1 

4 

A-11 

4 

scrub 

inc. 

inc. 

L. K. 

inc. 

inc. 

inc. 

inc. 

inc. 

inc. 

inc. 

1 .o 

0.08 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

1 .o 

1 .o 

1 .o 

1 .o 

1 .o 

1 .o 

0.02 

inc. 

R.F. 3 

scrubber 

(2-3) 

(1-4) 

inc. 

Power boiler ' 

4 

3 

3 

4 

(3.4) 

0.3 

0.3 

0.3 

0.02 

0.3 

002 

02 

13 

1 

C7 
Mill 

Size 

Avg . Kraft 

Prod. 

(Kraft) 

(Cap. ) 

__ Company 1 docation t Pd - - -- Tennessee 

Bowater 

Packaging 

Texas 

Champion 

I.P. 

@vens-Illinois 

Southland 

South1 and 

Temple-Fos tex 

Chesapeake 

Con ti nen tal 

Union Camp 

Wes tvaco 

Boise Cascade 

Crown Zel lerbach 

Crown Zellerbach 

Longvi ew 

St. Regis 

Weyerhaeuser 

Virginia 

Uashi ngton 

Cal houn 

Counce 

Pasadena 

Texarkana 

Orange 

Houston 

Lufkin 

Evadale 

West Point 

Hopewell 

Frank1 in 

Covington 

dallola 

Camas 

Port Townsend 

Longvi ew 

Tacoma 

Everett 

500 

(5001 

(775) 

850 

(820) 

61 0 

1000 

(900 1 

650 

(500) 

400 

(400 1 

1250 

(1200) 

11 50 

(1150) 

896 

1430 

(1 500) 

1048 

(900) 

(1000) 

460 

(460) 

780 

(760) 

420 

(420) 

1600 

(1 900) 

1090 

(1040) 

360 

(375) 

Recovery Furnace control3 TRS 

lo. of Rating Year Tech- Level 

Jnite iianuf. t& Instal. niGue ai/T ADP - 

2 

i 

2 

1 

2 

1 

2 

3 

3 

2 

3 

1 

2 

2 

1 

3 

2 

1 

CE 6006320 pre-1965 BLO 2.1 6 

CE 420 DOSt-1965 2.1 

B6W 550 1971 BLO 0.5 

, B6W 750 1969 0.5 

550 1955 

’ BllJ 550(each) 1965 RLO 2.1 

CF 2.1 

CE 175 (each )ore-1 965 15.0 

R6 lJ 534 1966 BLO 2.1 

CE 1100 Dost-1965 

(oxvaen) 

500 DOSt-1965 BLO 

530 ore-1965 

4006200 ore-1965 

CE 900 Dost-1965 BLO 0.5 

CE 375(each)pre-1965 BLO 0.5 

CE 580 post-1965 BLO 0.5 

CE 1320 Dost-1965 BLO 0.5 

5806350 me-1965 

B6W 250 

165 

B6 W 350 

CE 660 

CE 725 

CE 1100 

CF. . 863 

467 

CE 365 

2-700 

1960 EL0 0.5 

1957 

1955 BLO 0.5 

post-1965 Low Odor 0.5 

Dost-1965 BLO 0.5 

ore-1965 

oost-1965 Low Odor 0.5 

ore-1965 BLO 

00S.t-1965 BLO 0.5 

post-1 965 

A-12 
Lime Kilns 

Size TRS 

No. of Tons (CaO) Level 

Units Per Day b/T A? 

1 

3 

1 

1 

1 

3 

2 

3 

3 

2 

3 

4 

2 

1 

.0.8 

0.8 

351 0.05 

-0.2 

261 . 0.8 

13) , 0.8 

85 ' 0.8 

36 1 0.8 

303 0.8 

445 0.8 

403 0.8 

0.8 

(total) 

(total) 

0.2 

207 I 0.2 

I 

I 0.2 

507 ; 0.2 

196 & 801 0.2 

140 0.2 

;: 

1 

4 

NO. (Six) pique +/T .~DP 

Digester Control 

Type Tech- Level 

6 

5 

9 

5 

2 

1 

6 

9 

1 

8 

1 

13 

2 

12 

2 

10 

5 

1 

9 

1 

9 

1 

18 

4 

4 

2 

6 

8 

( 500 1 

8 

B 

100 each 

B 

C 

( 1000) 

C 

( 500 1 

B 

(400 1 

8i1200) 

(200) 

8 (600) 

C (600) 

B (950) 

8 

: [;::I 

c (800) 

B 

C (150) 

8 

C 

inc. 0.02 

1.5 

inc. 0.02 

inc- 0.02 

1.5 

1.5 

1.5 

1.5 

0.02 

0.02 

0.92 

0.02 

inc. 0.02 

inc. 0.02 

8 Power . 0.02 

C inc. I 

8 (1600) inc. 0.02 

C 600 

8 -[240] inc. 0.02 

C (690) 

B (550) inc. 0.02 

Mu 1 tip 1ff e-e eqt 

Evaporator * 

Control TRS 

Tech- Level 

No. pique #IT ADP 

1 

2: 

1 

1 

2 

3 

3 

2 

4 

2 

3 

6 

2 

1 

inc. 

inc. 

inc. 

inc. 

inc. 

inc. 

inc. 

inc. 

inc. 

0.02 

1 .o 

0.02 

0.92 

1 .a 

1 .o 

1.0 

1.0 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

0.02 

Brown Stock Washer TRS L, 

NO. ADTPD Stseec ::fT ADP 

Capacity Washer Leve 1 

1 4 0.3 

1 

4 

3 

3 3 

A-1 3 
Eii 11 

Size 

Avg . Kraft 

Prod. 

(Kraft: 

(Cap. ) 

ComDanv Locat ion tpd . 

1: 

!dashin! - Meyerhaeuser 

ton 

'i kli scons in Consol ida ted 

Great Northern 

Hamnermi 11 

Mos i nee 

Longvim 650 

(306) 

NSSC 

ch. rec 

plant 

Wisc. Rapids 400 

(400) 

ch. rec 

plant 

(330) 

ch. rec 

plant 

kukauna 400 

(400) 

Nekoosa 31 0 

tbsinee -174. 

(175) 

New Mills (Planned or under construction) 

Scott Paper - Skowhegan. %ire - 750 TPD 

Potlatch Corp. - McGehee, Lrkansas - 500 TPD. 

n 3 Recovery Furnace Control TRS 

lo. of Racin ; '-'car Tech- Level 

!nits ?lanuf. tpd IFStal. nique BIT ADP -- 

2 ' B6W 

CE 

2 CE 

2 CE 

1 BLY 

1 66w 

1201) 1972 Low Odor 

350 pre-1965 BLO 

400(each)post-l965 BLO 

350 

165 

390 

250 

pre-1965 

pre-1965 

1960 

1973 

BLO 

Lou Odor 

0.5 

0.5 

0.5 

0.5 

0.5 
I I 0.2 

0.8 

O.& 

C 1.1 

scrubber 2. 

9 6 1.5 

6- c 1.5 

6 B 

(17s) 

1.5 

hltiple-effect 

Evaporator 

Control TRS 

Tech- Level 

No. nique &IT ADP 

I 

inc. 0.02 

i 

1 .o 

1 

1 .o 

1 .o 

1 .o 

Brown Stock Masher TRS 

No. AWPD Stapes */T .E.?, Capacity Washer Level 

0.15 7.075 5 

0.6 0.3 20 

15.0 7.5 550 

Line Kiln 0.05 3.025 10 

0.1 0.05 20 

0.2 0.1 M 

Recovery Furnac 1 

0.5 9.25 17.5 

2.1 1.05 70 

Digester 

-. . 

0.8 3.4 

0.01 0.05 

1.1 0.55 

1.5 9.75 

0.08 . 0.04 

0.01 0.05 4' 

Mu1 tiple-effect 

Brown Stock Washer 0.01 

Evaporator 

1 .o 0.5 

0.3 0.15 

0.05. 

1 iij 

<5 

7000 

9500 

<5 

350 

6700 

45 

0.3 

i 

1 

1-15 

I 

APPENDIX B 

DATA SUMMARY 

KRAFT PULP MILLS 

Recovery Furnaces , Smelt Dissolving Tanks, Lime Ki Ins , and Incinerators 

Results are summarized for tests conducted by EPA at 6 kraft pulp mills. 

At these mills a total of 9 TRS tests; 3 recovery furnaces, 2 smelt dissolving 

tanks, 3 lime kilns, and one incinerator,were conducted by EPA. Emission 

data obtained from operators or state agencies are also reported for some 

of the facilitits. 

TRS EMISSION DATA 

Incinerator: 

The i nci nerator hand1 es the noncondensabl e gases from a conti nilous 

digester system and a mu1 tiple-effect evaporator system. The 

continuous digester was producing 670 tons of pulp per day. 

The incinerator was operating at 1000°F with a retention time 

for the gases of at least 0.5 seconds. Natural gas is fired in 

the i nci nera tor. 

Recovery Furnaces : 

A. Conventional type recovery furnace designed for an equivalent 

pulp production rate of 657 tons per day. TRS emissions are 

control 1 ed by using black 1 iquor oxidation and maintaining proper 

furnace operation. 

- 

The furnace was operating near its design 

capacity duri ng the EPA test period. Continuous monitoring data 

were also obtained frorn the operator. 

B-1 
B. low-odor type recovery furnace designed for an equivalent pulp 

production of 300 toris per day. 

furnace was operating at a rate of about 345 tons of pulp per 

day. TRS emissions are controlled by eliminating the direct corltact 

evaporator and maintaining proper furnace operation. Noncondensabl e 

gases from the brown stock washer system are burned in thfs furnace. 

Continuous monitoring data were also obtained from the state agency. 

During the EPA testing, the 

D. Conventional type recovery furnace designed for an equivhlent pulp 

production rate of 602 tons per day. TKS emissior?s are controjlcd 

by black liquor oxination agd maintaining pmper Furnace opecatqon. 

Low-odor type recovery furnace operatir:lj at an equivalent pulp 

production rate of about 200 tons per day. 

control 1 ed by mai ntai n-i ng proper furnace operati an. 

obtained from the state agency. 

Low-odor type recovery furnace designed for an equivalent pulp 

production rate of about 863 tons per day. 

controlled by maintaining proper furnace operation. 

obtai ned from state agency. 

H. 

TRS emissions are 

Data were 

K. 

TRS emissions are 

Data were 

Smel t Di ssol vi ng Tanks 

D. A wet fan type scrubber is employed to control the particulate 

emissions. 

The associated recovery furnace operates at an equi Val ent pulp 

production rate of 570 tons per day. 

E. A wet fan type scrubber is employed to control the particulate 

emissions. Fresh water is used as the scrubbing medium. The 

associated recovery furnace operates at an equivalent pulp production 

rate of 770 tons per day. 

Weak wash liquor is used as the scrubbing medium. 

B-2 
Lime Kilns 

D. Rotary lime kiln operating at an equivalent pulp production rate 

of 570 tons per day. 

proper ki 1 n combus ti on and proper 1 ime mud washing . 

gases from the multiple-effect evaporators are burned in the kiln. 

Rotary lime kiln operating at an equivalent pulp production rate 

of about 770 tons per day. TRS emissions are controlled by 

maintaining proper combustion in the kiln, maintaining proper 

lime mud washing, and using a caustic solution in the particulate 

scrubber. 

evaporators, condensate stripper, and miscellaneous storage tanks 

are burned in the kiln. 

from the operator. 

Rotary lime kiln operating at an equivalent pulp production rate 

of about 320 tons per day. TRS emissions are controlled by maintaining proper combustion in the kiln and proper lime mud washing. 

Noncondensable gases from the di gesters , mu1 tiple-effect evaporators, 

and turpentine system are burned in the kiln. 

TRS emissions are controlled by maintaining 

Noncondensabl e 

E. 

Noncondensable gases from the digesters, mu1 tiple-effect 

Continuous monitoring data were also obtained 

K. 

0. Rotary lime kiln not tested by EPA. Continuous monitoring data 

was obtained from the local agency. TRS emissions are controlled 

by maintaining precess combustion in the kiln. 

B-3 
Table B-1- TRS and SO2 Emissions from Incineration 

FACILITY - Incinerator 

Sumarv of Results 

Run Number 1 

Date - 1972 10/5 

Test Time - minutes 240 

Production Rate - TPH 

Stack Effluent 

- 

Flow rate - DSCFM (XlnflC) 2610 

Flow rate - DSi;b/tirn 

Temnerature - OF 80 5 

Water vanor - Vol. % 6,3 

CO2 - \dol. % dry 2.6 

02 - Vol. % dry 11.8 

CO - Dpm 0 

TRS Emissions 

rmm 

- 

2.8 

1 b/hr 1.5 

lb/ton of nul^ 0.06 

2 Emissions 

25 Dnm 

9.4 1 b/hr 

lb/ton of nU1D 0.4 

2 

10/6 

240 

- 

2223 

.. 

805 

4.3 

2.4 

12.0 

0 

0.4 

0.2 

0.007 

306 

96.9 

3.8 

3 

10/7 

240 

c 

2302 

L 

805 

5.4 

2.1 

12.7 

0 

1.6 

0.6 

0.02 

1050 

358 

13.9 

4 

12/13 

240 

- 

- 

- 

- 

- 

9.0 

15.7 

0 

0.9 

0.4 

0.02 

F 

- 

- 

6-4 
Table B-2 - TRS and SO2 Emissions from Recovery Furnace A 

FACILITY - Recovery Furnace A 

Sumnarv of Results 

Run Number 1 2 3 4 5 6 

Date - 1972 6/3 6/ 4 6/ 5 6/ 6 6/7 6/8 

Test Time - minutes 240 240 240 240 240 240 

Production Rate - TPH - - - - - - 

Stack Effluent 

Flow rate - DSCFM (XlnWl) 142 L 145 148 - - !- 

Flow rate - DSCF/ton - c - - - - 

Temperature - OF 31 4 - 304 303 - - 

Water 25.5 - 25.3 21.9 - - vanor - Vol. % 

C02 - Vol. % dry 10.4 8.2 10.7 11.8 12.9 11.1 

02 - Vol. % dry 10.7 11.4 11.4 10.1 10.1 9.9 

CO - ppm 153 93 84 95 102 51 

TRS Emi s s i ons 

ppm 2.0 1.4 1.4 1.5 0.7 1.6 

1 b/hr 1.5 1.1 1.1 1.2 0.6 1.2 

itr/ton of nu111 - - - - - - 

SO7 Emi s s i ons 

mm 45 116 79 118 50 119 

1 b/hr 85.0 - - - - - 

lb/ton Of nUlD - - - - - - 

B -5 
Table 8-3 - TRS and SO2 Emissions from Recovery Furnace B 

FACILITY - Recovery Furnace B 

Sumnarv of Results 

Run Number 1 2 3 4 5 

Date - 1972 7/13 

Test Time - minutes 240 240 240 240 240 

Production Rate - TPH - c - - - 

Stack Effluent 

7/14 7/15 7/18 7/19 

Flow rate - DSCFM (XlfVVl) 85 84 86 - - 

Flow rate - DSCF/ton - - - - 

Temnerature - OF 

Water vaDor - Vol. X 

CO2 - Vol. % dr,y 

02- - Vol. % dry 

co - Dpl"l 

TRS Emi ssi ons 

DDm 

1 b/hr 

1b/ton of nulo* 

SO7 Emissions 

DDm 

1 b/hr 

lb/ton of nulo 

39 5 

- 

- 

.-. 

0 

1.6 

.05 

0.9 

- 

- 

400 

12.3 

8.T 

0 

0.2 

0.7 

.Ol 

41 5 

- 

12.4 

7,. 6 

0 

0.5 

0; 1 

.02 

12.7 12.0 

7.Y 8.0 

0 0 

0.3 0.4 

0.2 0.2 

.Ol .Ol 

6 

7/20 

240 

- 

- 

- 

- 

- 

12.4 

8.0 

0 

0.3 

0.2 

.01 '. 

* Based on 334.5 ATDPlday 

B -6 
Table 8-4- TRS an4 SO2 Emissions from Recovery Furnace D 

FACILITY - Recovery Furnace D 

Sumarv of Results 

Run Number 1 2 3 4 5 

Date - 1972 11/11 11/12 11/13 11/14 11/15 

Test Time - minutes 240 240 240 240 240 

Production Rate - TPH - - - - - 

Stack Effluent 

Flow rate - DSCFM ( Xl 000) 73.2 73.2 73.2 73.2 73.2 

Flow rate - DSCF/ton 

Temoerature - OF 

Water vaoor - Vol. % 35 35 35 35 35 

C02 - Vol. % dr.y 

02 - Vol. % dry 

CO - ppm 

TRS Emissions 

Dnm 

1 b/hr 

1 b/ton of DUlD 

SO7 Emissions 

DDm 

1 b/hr 

lb/ton of nulr, 

3.1 2.8 3.9 7 .O 2.8 :* ':. 

55.1 48.9 53.7 12.5 46.0 

15.5 * 1.0 22.9 5.0 14.2 

162' 10 239 52 149 

- - - - - 

B -7 
Table B-5 

ADDITIONAL TRS EMISSION DATA 

FOR RECOVERY FURNACES* 

Recovery Furnace A 

TConcentrati on 

(ppm, daily average 

Month Maximum Average 

basis) 

July 1971 

Aug . 

Sept . Oct. 

Nov. 

Dec . 

Jan. 1972 

Feb . 

March . 

April 

May 

June 

July 

Aug 

Sept. 

Oct . 

6.0 

20.0 

5.0 

10.9 

- 4.4 

9.8 

5.5 

3.3 

2.5 

5.3 

' 5.5 

8.2 

9.8 

9.0 

4.9 

6.1 

3.1 

2.4 

9.5 

2.8 

1.3 

1.8 

1.6 

1.3 

1 .o 

2.0 

2.1 

3.8 

3.7 

3.3 

2.9 

2.2 

Recovery Furpace B 

S Concentration 

(ppm, daily average 

Month Maximum Average 

basis) 

April 1972 

May 

June 

July 

Aug .- 

Oct. 

Nov . 

DeC. 

Jan. 1973 

Feb. 

March 

Apri 1 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 

1.4. 

2.3 

2.8 

4.6 

5.0 

1.9 

0.7 

1 .o 

1.5 

2.6 

2.4 

1.5 

1.6 

1.9 

1.6 

. 3.1 

1.8 

2.0 

1.6 

3.4 

0.7 

1.2 

1.5 

1.1 

1.5 

0.7 

0.4 

0.7 

0.8 

1 .o 

0.9 

0.8 

1 .o 

1.1 

1 .o 

1.2 

0.8 

0.9 

0.8 

1.6 

*Tested by operators using barton titrators. 

B-8 
Table B-5 (cent..) 

Recovery Furnace A 

TRS Concentration 

(ppm, daily average 

basis) --. J Month Maximum Average 

I 

Recovery Furnace H 

TRS- Concen tra t i on 

(ppm, daily average 

Month Maximum Average 

basis) 

April 1972 3 2.1 

May 4 2.1 

June 7 3.5 

June 1972 8 3.1 

July 4 2.4 

Aug L 4 1.9 - 

Sept. 2 1.3 

Oct. 6 1.8 

ADDITIONAL TRS EMISSION DATA 

FOR RECOVERY FURNACES 

Recovery Furnace B 

VRS Concentration 

(ppm, daily average 

basis) 

Month Maxi mum Averwe __- _. 

Jan. 1974 1.4 0.8 

Feb. 1.9 1.3 

March 5.0 1.6 

Apri 1 2.4 1.2 

May 1.8 1 .o 

June 1.5 1 .o 

Recovery Furnace K 

'FRS Concentration 

(ppm, daily average 

Month Maxi mum Average 

.. 

basi s) 

Aug. 1973 6.2 1 .o 

Sept. 32 -0 5.2 

Oct. 7.3 2.4 

Nov. 17.0 4.1 

Dec . 1.2 0.7 

Jan. 1974 1.8 0.6 

Feb. 2.4 1 .o 

March 9.7 2.3 

Apri 1 3.0 1.4 

May 3.4 1.4 

B-9 
Table 6-6 

TRS EMISSION DATA FOR A CROSS RECOVERY FURNACE* 

Days TRS (4-hour) 

Sulfidi ty Average TRS Maximum 4-Hour Emissions Greater 

Month Ranqe (%) Eriissions (ppm) TRS Emissions (ppm) than 25 ppm 

Oct 76 22 - 36 12.5 54.5 2 

Nov 76 28 - 33 24.3 

Dec 76 28 - 34 9.5 

Jan 77 27 - 36 7.7 

Feb 77 27 - 35 8.0 

51.2 

43.2 

36.5 

48.0 

* Tested by operator using barton tatrator. 

B-10 
TableB-7 - TRS Evissions frorr Smelt Dissolying Tank D 

FACILITY - Smelt Dissolving Tank D 

Sumnarv of Results 

Run Number 1 2 3 

Date - 1973 10131 11/1 11/2 

Test Time - minutes 240 240 240 

Production Rate - TPH 25.1- 25.9 25.6 

Stack Effluent 

Flow rate - DSCFM 9000 8880 9400 

Flow rate - DSCF/ton 21 51 4 20571 22031 

Temnerature - OF 

Water vaDor - Vol. % 37 . 41 40 

C02 - Vol. % dr.y 

02 - Vol. % dry 

CO - opm 

TRS Emissions 

mm 

1 b/hr 

1 b/ton of ~ylo 

8.1 8.8 6.9 

0.43 0.44 0.38 

0.01 7 0.017 .015 

B-11 
Table B-8- TRS Emissions from Smelt Dissolving Tank E 

FACILITY - Smelt Dissolving Tank E 

Sumnarv of Results 

Run Number 1 2 3 

Date - 1973 9/18 9/19 9/20 

Test Time - minutes 240. 240 240 

Production Rate - TPH 30.1 34.1 31.3 

Stack Effluent 

Flow rate - DSCFM 19542 18740 19100 

Flow rate - DSCF/ton 389 54 32974 3661 3 

Temrature - OF 

Water vmor - Vol. % 26 26 23.3 

Co;! - Vol. % dr.y 

- Vol. X dSj 

CO - ppm 

TRS Emi s s i ons 

2.4 1.9 2.7 

0.27 0.20 0.28 

0.009 .006 .009 

. PDm 

1 b/hr 

1 b/ton of pulp 

8-12 
Table B-’3 -Tf6 Emissions from Lime Kiln D 

FACILITY - Lime Kiln D 

Sumnary of Results 

,n Number 1 2 3 4 5 6 

Date - 1973 11/5 11/7 11/7 11/7. 11/8 11/8 

Test Time - minutes 240 240 240 240 240 240 

Production Rate - TPH 

Stack Effluent 

Flow rate - DSCFM (Xlnm) 

Flow rate - DSCF/ton 

Temnerature - OF 

Water vaDor - Vol. % 43 35 40 38 41 31 

CO2 - Vol. % dry 

02 - Vol. % dry’ 

co - DpmTRS Emi ssi ons 

3.5 24.1 2.8 5.7 4.6 17.8 PDm 

1 b/hr 

lb/ton of pulp 

B-13 
Table B-10- TRS Emissions from Lime Kiln E 

FACILITY - Lime Kiln E 

Sunarv of Results 

Run Number 1 2 3 4 5 6 

Date - 1973 9/ 24 9/ 25 9/ 26 9/26 9/27 9/27 

Test Time - minutes 240 240 240 240 240 240 

Production Rate - TPH 

Stack Effluent 

Flow rate - DSCFM (XlOOC)) 

Flow rate - DSCF/ton 

TemDerature - "F 

#ater vaDor - Vol. % 

C02 - Vol. % dr.y 9.4 10.2 10.0 9.8 8.2 9.8 

9 - Vol. % d~ 13.2 11 .o 12.2 12.0 13.1 11.8 

- 

CO - ppm 

TRS Emi ssi ons 

PPm 

1 b/hr 

1.7 0.8 0.5 0.4 0.3 0.5 

lb/ton of pulp 

B-14 
Table B-11-TRS and SO2 Emissions from Lime Kiln K 

FACILITY - Lime Kiln K 

Sumarv of Results 

Run Number 1 2 3 4 5 6 

Date - 1974 4/5 4/ 5 4/9 4/9 4/10 4/10 

Test Time - minutes 240 240 * 240 240 240 240 

Production Rate - TPH L .L - I - c 

Stack Effluent 

Flow rate - DSCFM (X1r)r)r)) 13.8 13.8 14.0 13.4 13.6 14.2 

L - ). - - 0 Flow rate - DSCF/ton 

TemPerature - OF 142 142 :.- 146 152 155 154 

Water vaDor - Vol. % 21.8 21.8 22.9 26.0 25.8 26.8 

C02 - Vol. % dr.y 13.0 13.0 14.2 14.2 14.6 14.2 

02 - Vol. % dry 7.6 7.6 7.1 7.1 6.4 7.2 

co - Dpm 0 0 .o 0 0 0 

TRS Emissions 

PPm . 4.6 12.0 4.5 4.8 4.0 5.2 

1 b/hr 0.34 0.88 0.33 0.34 0.29 0.39 

lb/ton of pulp 9 - 0- - 9 - .. SO7 Emissions 

mm 52 42 25 18 16 37 :: 

1 b/hr 7.2 5.8 3.5 2.4 2 -2 5.2 

- c. - 9 lb/ton of pulp - .c 

B-15 
Table 8-12 

ADDITIONAL TRS EMISSION DATA 

FOR LIME KILNS* 

Lime Kiln E 

TRS ConcentratTon 

(ppm, daily average) 

’ Month Maxi mum Average 

May 1973 

June 

%July 

.Aug. 

Sept. 

Oct. 

Nov . 

Dec . 

Jan. 1974 

.Feb . 

March 

Apri 1 

kY 

1.4 

3.4 

2.1 

1 .?I 

10.1 

7.1 

5.9 

8.9 

3.4 

2.6 

* 

0.7’ 

3.1 

2.9 

0.3 

0.7 

0.4 

0.3 

1.5 

1 .o 

0.8 

1 .o 

0.6 

0.2 

0.1 

0.6 

0.7 

Lime Kiln 0 

S Concentration 

(ppm, daily average) 

Month Maximum Average 

Jan. 1973 

Feb. 

March 

Apri 1 

May 

June 

July 

Aug . 

Sept. 

Oct. 

Nov . 

Dec . 

Jan. 1974 

Feb. 

March 

Apri 1 

May 

14 

20 

14 

32 

16 

10 

99 

12 

17 

6.8 

9.3 

7.6 

9.6 

4.7 

3.4 

4.5 

3.8 

5.0 

34 8.2 

12 5.7 

22 9; 8 

30 17.9 

33 21 .1 

30 19.3 

40 16.2 

25 12.3 

Average = 9.7 

*Tested by operators using barton titrators. 

B-16 
Table B-12 (CONTINUED) 

Lime Kiln P 

TRS Summary: 4-Hour Averages 

4-Hour Averages Monitored 

% % % % % 

Month <5 PPm >5/ 40 ppm >lo/ <20 ppm >20 ppm >40 ppm 

February ‘75 45 26 

March ‘75 65 25 

April ‘75 63 16 

May ‘75 53 25 

9 20 12 

7 7 2 

12 9 5 

13 8 2 

B-17 

.- 

TABLE C-1 

TMPACT OF CONTKCiLItiG THE VARIOUS TRS SOURCES CN 

AMBIENT TRS CONCENTRATION FROM A 907 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: vg/m3 Frequency - (One-hour average) I of Concentrations 

Qncontrol led Distance from Source (km) Greater than 1/2 Percent 

Level @ 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum Reducti ona 

- Source Control Techniques 

Recovery Furnace BLO (20 ppm) 

Digester Scrubber 

Multiple-Effect Scrubber 

BLO (5 ppm) 

Incineration 

Evaporator Incineration 

2465 100 64 38 16 28 95.9 

2465 25 16 10 4 28 99.0 

6000 4680 1716 1090 3 22.0 

6000 ob - 100.0 3 

1175 96 ' 60 36 4 91.8 

1175 ob -__3 - 100.0 

Lime Kiln 1) Process Controls 256 64 23 18 15 12 1 75.0 

2) Process Controls + 2 56 16 6 4 4 3 1 93.8 

Hioh Eff. Mud Washing 

3) Process Controls + High 256 

Eff. Mud Washing + 

Caustic Scrubbing 

Yrown Stock Incineration 

Black Liquor Incineration 

blasher System 

Oxidation System Molecular Oxygen 

Sme 1 t Di ssol vi ng 

lank 

Condensate StripDing Scrubber 

Sys tern Incineration 

Fresh Water 

113 

96 

96 

83 2 2 2 1 96.9 

8 3 2 

19 6 3 1 1 

oc - > 

172 22 8 6 

4400 2200 306 165 

4400 ob ______ ______+ 

a Reduction from uncontrolled averaae level 

Gases arc! assumed burned in the lime kiln. 

include unburned TRS portion of these gases. 

The levels from the lime kiln 

34 

25 

- 

3 

25 

- 

92.9 

80.2 

100.0 

87.2 

50.0 

100.0 

0 

U 

v) 

W 

m % W -0 

v, 

n m 

0 

z 

z 

x If 

c 0 U 

l-4 

m 

v) 

NO vent gases. 
TABLE C-2 

IMPACT OF CONTROLLING THF VARIOUS TRS SOURCES OH AMBIENT TRS CONCENTRATION FROM A 907 MEGAGRAMSIDAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: vg/m3 Frequency - (24-hour average) % of Concentrations 

ancontrol led Distance from Source (km) .Greater than 1/2 Percent 

Level @ 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum Reductiona Source Control Techniques 

Recovery Furnace BLO (zo'ppm) 

BLO (5 ppm) 

Digester Scrubber 

643 26 16 9 4 29 96.0 

580 450 150 68 48 22.4 

643 64 2 1 29 99.0 

Incineration 580 Ob -- 100.0 

Incineration 115 Ob > -- 100.0 

2) Process Controls + 56 42 1 1 1 1 92.9 

Multiple-Effect Scrubber 115 10 6 3 55 91.3 

Evaporator 

Lime Kiln 1) Process Controls 56 14 7 4 3 2 1 75.0 

Hioh Eff. Mud Washing 

Eff. Mud Washina + 

Caustic Scrubbing 

3) Process Controls + High 56 21 1 1 1 1 96.4 

Brown Stock Incineration 

Black Liquor Inci nera ti on 

Smelt Dissolving Fresh ldater 

Condensate Stripping Scrubber 

Washer System 

Oxidation System Molecular Oxygen 

Tank 

System Incineration 

30 

25 

25 

2 1 1 26 93.3 

52 1 1 1 20 80.0 

OC > 100.0 -- 

16 2 1 1 46 87.5 

840 420 66 34 30 50.0 

840 Ob - -- 100.0 

a Reduction from uncontrolled averaoe level 

Gases are assumed burned in the lime kiln. The levels from the lime kiln 

include unburned TRS portion of these gases. 

No vent gases, C 
0 

I 

w 

TMPACT OF CONTROLLING THE VARIOUS TRS SOURCES ON 

AMBIENT TRS CONCENTRATION FROM A 454 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: ug/m3 Frequency - 

Control Techniques Level Q 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum 

(10 second average) % of Concentrations 

Uncontrolled Distance from Source (km) IGreater than 1/2 Percent 

Redu ct i on a Source 

Recovery Furnace BLO (20 ppm) 5250 210 135 80 34 33 96.0 

BLO (5 ppm) 5250 53 35 20 8 33 99.0 

Oi ges ter Scrubber 9800 7645 2790 1775 3 22.0 

Ob - 100.0 

Ob - 100.0 

9800 > 

Mu1 t ipl e- Ef fec t ’ Scrubber 1950 156 98 58 4 92.0 

Incineration 1950 

Lime Kiln 1) Process Controls 440 110 40 30 25 21 1 75.0 

2) Process Controls + 440 28 10 8 6 5 1 93.6 

3) Process Controls + High 440 14 5 4 3 3 1 96.8 

Incineration 

Evaporator 

Hiqh Eff. Mud Washinq 

Eff. Mud Washin? + 

Ca 11 s t i c Sc ru bb i ng 

Brown Stock Incineration 

Black. Liquor Incineration 

Washer System 

Oxidation System Molecular Oxygen 

Tank 

System Incineration 

Smelt Dissolving Fresh Water 

Condensate Stripping Scrubber 

370 25 9 6 19 93.2 

21 0 42 14 7 3 3 30 80.0 

210 OC > -- 100.0 

270 34 13 8 3 87.4 

91 00 4550 635 340 16 50.0 

100.0 91 00 Ob -- 

a Reduction from uncontrolled average level 

Gases are assumed burned in the lime kiln. The levels from the lime kiln 

include unburned TRS portion of these gases. 

No vent gases. 

C 
TAN€ C-4 

IMPACT OF CONTROLLING THE VARIOUS TRS SOURCtS ON 

AMBIENT TRS CONCENTRATION FROM A 454 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: pg/m3 Frequency - (One-hour average) X of Concentrations 

Uncontrolled Distance from Source (km) Greater than 1/2 Percent 

Control Techniques Level (a 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum Redu c t i on a Source 

Recovery Furnace BLO (20 ppm) 

Digester Scrubber 

BLO (5 ppm) 

Incineration 

Mu1 tip1 e-Effect Scrubber 

Incineration Evaporator 

Lime Kiln 

Brown Stock 

Black Liquor 

Smelt Dissolving 

Condensate Stripping 

Washer System 

Ox i da t i on Sy s tem 

Tdnk 

System 

1610 64 41 24 10 33 96.0 

1610 16 10 6 3 33 99.0 

3000 2340 860 545 3 22.0 

3000 Ob > - 100.0 

1) Process Controls 136 

2) Process Controls + 136 

Hiqh Eff. Mud Washing ' 

3) Process Controls + High 

Eff. Mud Washing + 

Caustic Scrubbing 

1-36 

Incineration 113 

600 48 30 18 

600 Ob 

Incineration 

Molecular Oxygen 

Fresh IJater 

Scrubber 

Incineration 

66 

66 

84 

2800 

28ao 

34 12 9 8 7 

93 3 2 2 

52 1 1 1 

8 3 2 

13 4 2 1 1 

___, oc -. . - -- 

11 4 3 

1400 195 105 

a Reduction from uncontrolled averaw level 

Gases are assumed burned in the lime kiln. The levels froti the lime kiln 

include unburned TRS portion of these gases. 

No vent gases. 

I 

C 

4 92.0 

- 100.0 

1 

19 

30 

- 

3 

16 

- 

75.0 

93.4 

96.3 

92.9 

80.3 

100.0 

86.9 

50.0 

100.0 
TABLE C-5 

IMPACT OF CONTROLLING THE VARIOUS TRS SOURCES ON 

AMBIENT TRS CONCENTRATION FROM A 454 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: ugh3 Frequency - 

Source Control Techniques Level @ 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum 

(24-hour average) % of Concentrations 

Uncontro I I ed Distance from Source (km) !Greater than 1/2 Percent 

Reducti ona 

Recovery Furnace 

Di ges ter 

Mu1 ti pl e- Ef fec t 

Lime Kiln 

Evaporator 

Brown Stock 

Black Liquor 

Smelt Dissolving 

Condensate Stripping 

Washer System 

Oxidation System 

' Tank 

System 

BLO (20 ppm) 

BLO (5 ppm) 

Scrubber 

Incineration 

Scrubber 

Incineration 

1) Process Controls 

2) Process Controls + 

High Eff. Mud Washing 

3) Process Controls + High 

Eff. Mud Washing + 

Caustic Scrubbing 

Incineration 

I nc i nera ti on 

Molecular Oxygen 

Fresh Water 

Scrubber 

Incineration 

430 

430 

290 

290 

60 

60 

32 

32 

32 

17 

17 

17 

8 

420 

420 

17 11 6 2 

43 1 1 

Ob * 

53 2 

Ob __1_3 

84 2 2 1 

21 1 1 1 

226 76 34 

1 1 1 

31 1 <1 <1 

I 

1 1 1 

210 28 17 

Ob h 

Reduction from uncontrolled average level 

Gases are assumed burned in the lime kiln. The levels from the lime kiln 

include unburned TRS portion of these gases. 

NO vent gases. 

a 

27 

27 

48 

- 

55 

- 

4 

4 

4 

52 

19 

- 

46 

37 

- 

96.0 

99.1 

22.1 

100.0 

91.7 

100.0 

75.0 

93.8 

96.9 

94.1 

82.4 

100.0 

50.0 

100.0 
TABLE C-6 

IMPACT OF CONTROLLING THE VARIOUS TRS SOURCES ON 

AMBIENT TRS CONCENTRATION FROM A 1350 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: ugh3 Frequency - 

(10 second average) % of Concentrations 

Uncontrolled Distance from Source Ikm) ,Greater than 1/2 Percent 

Level @ 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum Reduct i ona Source Control Techniques 

Recovery Furnace 

Digester 

Mu1 t ipl e-Ef fect 

Evaporator 

Lime Kiln 

0 1 

m 

Brown Stock 

Black Liquor 

Smelt Dissolving 

Condensate Stripping 

Washer System 

Oxidation System 

. Tank 

System 

BLO (20 ppm) 

BLO (5 ppm) 

Scrubber 

Incineration 

Scrubber 

Incineration 

1) Process Controls 

1) Process Controls + 

Hiah Eff. Mud Washing 

3) Process Controls + High 

Eff. Mud Washing + 

Caustic Scrubbing 

Incineration 

Incineration 

Molecular Oxygen 

Fresh Water 

Scrubber 

Incineration 

11,785 

11,785 

29,000 

29 , 000 

5,750 

5,750 

1,280 

1,280 

1,280 

555 

490 

490 

840 

21,000 

21,000 

470 305 180 75 

120 75 45 20 

22,930 8370 5325 

1 

470 295 175 

Ob 

320 115 88 73 62 

80 29 22 18 16 

40 14 11 9 a 

37 14 9 

98 33 14 7 5 

OC 9 

105 39 24 

10,500 1460 780 

ob * f 

Reduction from uncontrolled averaae level 

Gases are assumed burned in tne lime kiln. The levels from tne lime kiln 

include unburned TRS portion of these gases. 

No vent gases. 

a 

C 

28 

28 

3 

- 

4 

- 

1 

1 

1 

34 

25 

- 

3 

25 

- 

96.0 

99.0 

20.9 

100.0 

91.8 

100.0 

75.0 

93.8 

96.9 

93.3 

80.0 

100.0 

87.5 

50.0 

100.0 
TABL€ C-7 

IMPACT OF CONTROLLING THE VARIOUS TRS SOURCES ON 

AMBIENT TRS CONCENTRATION FROM A 1350 MEGAGRAMVOAY 

KRAFT PULP MILL 

0 I 

U 

Maximum Ambient Concentration: vg/m3 Frequency - 

Source Control Techniques Leyel 13 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum 

(One-hour average) % of Concentrations 

Uncontrolled Distance from Source (km) Greater than 1/2 Percent 

Reduct i ona 

Recovery Furnace BLO (20 ppm) 3,750 150 97 57 24 28 96.0 

BLO (5 ppm) 3,750 37 24 14 6 28 99.0 

Digester Scrubber 9,000 7,020 2,575 1,640 3 22.0 

Incineration 9,000 Ob - 100.0 

Incineration 1,775 Ob 100.0 

> 

Mu1 tip1 e-Effect Scrubber 1,775 154 90 53 4 91.3 

Lime Kiln * 1) Process Controls 385 96 34 27 22 19 1 75.0 

385 24 9 6 6 5 1 93.8 

Evaporator 

2) Process Controls + 

Hiqh Eff. Mud Washing 

Eff. Mud Washinu + 

Caustic Scrubbing 

3) Process Controls + High 385 12 4 3 3 2 1 96.9 

Brown Stock Incineration 175 12 4 3 34 94.8 

Black Liquor Incineration 150 30 10 5 2 2 25 80.0 

Smelt Dissolving Fresh Water 255 32 12 9 3 87.5 

Condensate Stripping Scrubber 6,600 3,300 460 250 25 50.0 

blasher System 

Oxidation System Molecular Oxygen 150 oc - 100.0 

Tank 

System Incineration 6,600 Ob > - 100.0 

a Reduction from uncontrolled averaae level 

Gases are assumed burned in the lime kiln. The levels from the lire kiln 

include unburned TRS portion of these gases. 

No vent gases- C 
0 I 

W 

IMPACT OF CONTROLLING THE VARIOUS TRS SOURCES ON 

AMBIENT TRS CONCENTRATION FROM A 1350 MEGAGRAMS/DAY 

KRAFT PULP MILL 

Maximum Ambient Concentration: v9/m3 Frequency - (24-hour average) % of Concentrations 

Uncontrolled Distance from source (km) 'Greater than 1/2 Percent 

Source Control Techniques Level @ 0.3 km 0.3 0.6 1.0 1.5 2.0 the Maximum Reducti ona 

Re cove ry Fu r na c e 

Digester Scrubber 

BLO (20 ppm) 

BLO (5 ppm) 

Incineration 

Mu1 tiple-Effect Scrubber 

Incineration Evaporator 

965 40 25 15 5 29 95.9 

965 10 6 4 1 29 99.0 

870 Ob - 100.0 

87 0 680 230 100 48 21.8 

r 

175 15 9 5 55 91.4 

175 Ob > - 100.0 

Lime Kiln 1) Process Controls 80 20 10 6 4 3 1 75.0 

2) Process Controls + 80 53 2 1 1 1 93.8 

tiiqh Eff. Mud Washing 

3) Process Controls + High 80 

Eff. Mud Washing + 

32 1 1 1 1 96.3 

Caustic Scrubbi na 

45 3 1 1 26 93.3 Brown Stock Incineration 

Black Liquor Incineration 40 83 1 1 1 20 80.0 

Smelt Dissolving 25 3 1 1 46 88.0 Fresh Water 

Condensate Strippinq Scrubber 1,300 650 87 53 30 50.0 

Washer System 

Oxidation System Molecular Oxygen 40 OC - 100.0 9 

lank 

System Incineration 1,300. Ob - 100.0 > 

Reduction from uncontrolled averaqe level a 

Gases are assumed burned in the lime kiln. The levels from the lime kiln 

include unburned TRS portion of these gases. 

No vent gases. C 

U 
(Please read ItJrmictions on the reverse belore 

. RkPORT NO. 2. 

. TITLE AND SUBTITLE 

Kraft Pulping - Control of TRS Emissions from Existing 

Mills 

. AUTHOR(S) 

. PERFORMING ORGANIZATION NAME AND ADDRESS 

Office of Air Quality Planning and Standards 

Research Triangle Park, North Carolina 

DAA for Air Quality Planning and Standards 

U. S. Environmental Protection Agency 

Research Triangle Park, North Carolina 

Environmental Protection Agency 

27711 

2. SPCv%St2R::J.G AGE::CY i<AME A%0 C;C=RESS 

Office of Air, Noise, and Radiation 

27711 

5. SGi'PLEMENTARY NOTES 

7. KEY WORDS AND DOCUMENT ANALYSIS 

DESCRl PTORS ib. IDENTI FI E RS/OPEN ENDED TERMS IC. COSATI Field/Group 

I I 

completing) 

3. RECIPIENT'S ACCESSIOWNO. 

5. REPORT DATE 

March ___- 1979

6. PERFORMING ORGANIZATION CODE 

8. PERFORMING ORGANIZATION REPORT NO. 

10. PROGRAM ELEMENT NO. 

.. '11. CONCRACT/GRANT NO. 

13. TYPE OF REPORT AND PERtOD COVERED 

14. SPONSORING AGENCY CODE 

EPA/200/04 

Air pollution 

Pollution control 

Kraft pulp mills 

Total reduced sulfur 

Particulate matter 

Emission guidelines 

a. DISTRIBUTION STATEMENT 

Unlimited 

Air pollution control 

19. SECURITY CLASS (ThisReporr) 21. NO. OF PAGES 

Unclassified 210 

Unclassified 

20. SECURITY CLASS (Thispuge) 22. PRICE