p.1 

RCRA Box 1883 

Prepped by Ollie Stewart 

Document Number: 

106)1 ll-B-268 

Docket Number: 

A-90-19 

Printed 12/3/200810:42:17AM Sheet 106 of 171 
P.2 

MEMORANDUM 

DATE: 

TO: 

FROM: 

SUBJECT: 

A-90-19 

ll-B-268 

February 10, 1992 \ cpp^^^S^-

Leslie B. Evans and Debbie Stackhouse, EPA (MD-13) 

Roy V. Oommen, Radian 

Limits and Monitoring Parameters for 

Combustion/Scrubbing Systems Used to Control 

Halogenated Process Vent Streams 

SUMMARY 

The proposed hazardous organic NESHAP will require 

combustion control of some process vent streams. Where 

halogenated streams are combusted, scrubbers would be required to 

reduce emissions of halogens and hydrogen halides. This 

memorandum presents technical support for the emission limits and 

monitoring parameters for combustion/scrubbing systems used to 

control halogenated process vent streams. Data for establishing 

the limits were gathered from a survey of facilities producing 

ethylene dichloride compounds. 

Two provisions are being considered by the U.S. 

Environmental Protection Agency (EPA) for inclusion in the 

proposed standard for process vent emissions: (1) a scrubber 

would be required after an incinerator, boiler, or process heater 

if the total concentration of halogenated pollutants entering the 

combustion device is greater than 100 parts per million volume 

dry (ppmvd), and (2) the scrubber would be required to have a 

total halogen control efficiency of 99 percent. An outlet 

concentration limit of 0.5 milligrams per dry standard cubic 

meter (mg/dscm) may be provided as an alternative to the percent 

reduction for streams where 99 percent control would result in 

outlet levels below the detection limit and therefore be 

unmeasurable. This memorandum provides technical information 

supporting these provisions. 

Bonp»rht_o04 (It) 
P.3 

The proposed EPA Test Method 26A is recommended to measure 

the concentrations exiting the scrubber and to confirm the 

control efficiency of the scrubber during the required initial 

performance test. 

To ensure the scrubber continues to meet the standards after 

the performance test, the pH of the effluent scrubber solution 

from the last scrubber stage and the liquid-to-gas ratio (L/G) 

would be monitored. 

Further elaboration is presented in the following sections: 

Introduction (1.0), Data Collection (2.0), Scrubber Parameters 

for Surveyed Facilities (3.0), Potential Provisions for the 

Standard (4.0), Measurement Techniques (5.0), Scrubber Monitoring 

Parameters (6.0), and References (7.0). 

1.0 INTRODUCTION 

As part of the Hazardous Organic NESHAP (HON) development, 

the EPA has identified combustion as a viable method for 

controlling emissions of organic pollutants. However, the 

combustion of halogenated organic compounds (i.e., organic 

compounds containing chlorine, fluorine, etc.) may result in the 

formation and emission of species such as hydrogen chloride 

(HCl), hydrogen fluoride (HF), and chlorine (Cl2) which are also 

on the list of 190 hazardous air pollutants under Title III of 

the Clean Air Act Amendments. To ensure that combustion of 

halogenated pollutants will not adversely impact the environment, 

a secondary control device (a scrubber) is needed to reduce 

emissions generated by the primary control device (incinerator, 

boiler, or process heater). 

2.0 DATA COLLECTION 

A survey of chemical facilities producing halogenated 

compounds was conducted to identify the most common types of 

secondary control devices currently in use, and the resulting 

acid gas emissions from them. In order to make the survey 

manageable, the scope was limited to chemical facilities 

producing ethylene dichloride (EDC). Ethylene dichloride was 

monparhtmO*(Is) 2 
P.4 

chosen because it is produced in large quantities, and facilities 

producing EDC would be expected to have large acid gas releases 

and/or secondary pollution control devices in place. A total of 

five companies (BFGoodrich, Borden, Dow, Occidental, and PPG) in 

eight locations were surveyed.1"

13 Four of the eight plant sites 

produce vinyl chloride, and one produces polyvinyl chloride, as 

well as EDC. 

Table 1 presents the EDC production capacities of the eight 

facilities, their primary and secondary air pollution control 

devices, and the halogenated pollutants emitted from their 

primary control device. Seven of the eight facilities reported 

thermal incineration as the primary control device. The 

exception is Dow Chemical's Freeport plant, which reported that 

process vent emissions were sent to a flare. Quantitative data 

on emissions and control efficiencies were not supplied by this 

facility. Chlorine gas and HCl are the most common halogenated 

pollutants emitted from the incinerators at the seven facilities. 

Although only one of the eight facilities reported using 

flares as the primary control device, both the Texas Air Control 

Board (TACB)1**16 and the Louisiana Air Control Board (LACB)17 

indicated that flares are not prohibited from being used to 

control halogenated gas streams in their States. However, the 

TACB and LACB also indicated that flares are not normally used, 

and are usually discouraged from being used for this purpose. 

Neither the TACB or LACB impose concentration limits on 

halogenated compounds entering flares, so flare applicability is 

determined on a case-by-case basis using dispersion modeling. 

3.0 SCRUBBER PARAMETERS FOR SURVEYED FACILITIES 

The seven facilities reporting incineration as the primary 

control device also reported wet scrubbers as the secondary 

control device. Table 1 presents some of the characteristics of 

the scrubbers. All of the scrubbers use packed columns; six use 

caustic as the scrubbing solvent and one uses water. 

monparhtaO *(Is) 
Table 1. Existing Controls at Ethylene Dichloride Facilities1 

PLANT 

CODE COMPANY LOCATION 

EDC 

PRODUCTION 

CAPACITY 

(MM Kg/yr) 

PRIMARY 

CONTROL 

DEVICE 

COMPOUNDS 

EXITING 

PRIMARY 

DEVICE 

SECONDARY 

CONTROL 

DEVICE 

COLUMN 

TYPE 

SCRUBBING 

OPERATION SOLVENT 

A

2'3 BFGOODRICH LA PORTE 

B

3'4 BORDEN GEISMAR 

DOW 

D3.5 QO H 

,3.5 

G 

H 

DOW 

OCCIDENTAL 

OCCIDENTAL 

PPG 

FREEPORT 

OYSTER CREEK 

PLAQUEMINE 

TX 

LA 

TX 

TX 

LA 

720 

339 

727 

INCINERATOR 

INCINERATOR 

FLARE 

C1-, HCl 

C1-, HCl 

Trace Amounts 

of Other Halogens 

Trace Amounts 

of Halogenated 

SCRUBBER 

SCRUBBER 

NONE 

PACKED 

PACKED 

ND 

RECYCLE CAUSTIC 

RECYCLE WATER 

ND ND 

CORPUS CHRISTI TX 

CONVENT LA 

LAKE CHARLES LA 

500 

773 

364 

364 

1227 

INCINERATOR 

INCINERATOR 

INCINERATOR 

INCINERATOR 

INCINERATOR 

Compounds 

Cl2, HCl 

Trace Amounts 

of Other Halogens 

ci2, 

ci2, 

ci2, 

ci2, 

HCl 

HCl 

HCl 

HCl 

SCRUBBER 

SCRUBBER 

SCRUBBER 

SCRUBBER 

SCRUBBER 

PACKED 

PACKED 

PACKED 

PACKED 

PACKED 

RECYCLE 

ONCE 

THROUGH 

RECYCLE 

RECYCLE 

RECYCLE 

CAUSTIC 

CAUSTIC 

CAUSTIC 

CAUSTIC 

CAUSTIC 

ND no data 

1 References 1-13 

* plants that do not produce HCl 

3 plants that also produce vinyl chloride (VC) 

4 plants that also produce polyvinyl chloride (PVC) 

5 waste heat boilers 
P.6 

Table 2 presents the reported information on the performance 

of each scrubber, including: acid gas (HCl and Cl2) outlet 

concentrations, test methods used for determining acid gas 

concentrations, HCl design removal efficiency, pH of scrubbing 

liquid, exiting temperature of the effluent gas, and the maximum 

flow rate of effluent gas. For the surveyed facilities, Table 2 

indicates only two pollutants, HCl and CI2, were reported exiting 

the scrubber. Figure 1 presents the HCl and CI2 concentrations 

in the effluent gas from the scrubbers, by facility. Hydrogen 

chloride emissions ranged from 0.93 ppmvd to 72 ppmvd, with an 

average value of 33 ppmvd. Chlorine emission levels ranged from 

0.75 ppmvd to 26 ppmvd, with an average value of 11 ppmvd. All 

emissions data are corrected to 3 percent oxygen basis to 

correlate with the proposed HON standards. 

As Table 2 indicates, 8 of the 10 scrubbers have HCl design 

removal efficiencies equal to or above 99 percent. Scrubbers in 

facilities E (Dow) and G (Occidental) reported design removal 

efficiencies of 98 and 97 percent, respectively. All but one wet 

scrubber uses caustic as the solvent, with pH's ranging from 7.5 

to 10.5. The exception is Facility B (Borden), which uses water 

as the scrubbing liquid. All but one of the outlet gas 

temperatures were between 100 and 188 degrees Fahrenheit. The 

exception is Facility G (Occidental), which reported a value of 

389 degrees Fahrenheit. However, this value is suspect, as it is 

above the boiling point of water. Effluent gas flow rates range 

from 1,977 dscfm to 33,703 dscfm. 

4.0 POTENTIAL PROVISIONS FOR THE STANDARD 

Two provisions for combustor/scrubber systems are being 

considered by the EPA for inclusion in the HON standard: 

(1) scrubbing is required if the inlet concentration to the 

incinerator, boiler, or process heater is greater than 100 ppmvd 

of halogenated organic compounds, and (2) scrubbers must have a 

total halogen and hydrogen halide control efficiency of 

99 percent on a molar basis. 

monparhtmlH (-») 5 
Table 2. Scrubber Characteristics of the Surveyed Facilities 

ODE 

A 

B 

C 

D 

E 

F 

G 

H 

COMPANY 

BFGOODRICH 

BORDEN 

DOW 

DOW 

DOW 

OCCIDENTAL 

OCCIDENTAL 

PPG 

SCRUBBER 

NUMBER 

A-1 

B-1 

C-1 

D-l 

D-2 

D-3 

E-1 

F-l 

F-2 

G-1 

H-l 

H-2 

HCl 

DESIGN 

REMOVAL 

EFFICIENCY 

(%) 

99.9 

99.0 

ND 

99.9 

ND 

99.0 

98.0 

99.7 

99.7 

97.1 

99.1 

99.9 

SOLVENT 

PH 

8.5 

6.5-7.0 

ND 

9.5 

9.0 

10.5 

8.5 

8.5 

8.5 

7.5 

8.5 

9.0 

SC 

GAS 

EXIT 

TEMP 

(F) 

142 

140 

ND 

151 

150 

188 

100 

178 

179 

389 

139 

109 

RUBBER DATA 

REPORTED 

MAX. CONCENTRATIONS 

GAS IN THE EXIT GAS 

FLOW (ppmvd,§ 3% 02) 

RATE 

(DSCFM) HCl Ci2 

33703 

30698 

ND 

6195 

4601 

3823 

2788 

1935 

1977 

ND 

12653 

8820 

* 

* 

* 

* 

0 .93 

13 

ND 

63 

3 

42 

71 

26 

5 

1 

72 

62 

0 .75 

26 

ND 

17 

1 

27 

ND 

ND 

ND 

ND 

1 

1 

TEST 

METHOD 

TACB #10 

ND 

ND 

EPA 0050 

EPA 0050 

EPA 0050 

EPA 0050 

EPA 26 

EPA 26 

EPA 26 

ND 

ND 

* = Typical flow 

ND = No Data 
80 

Figure 1. HCI and CI2 Emissions 

Outlet From Scrubber 

70 -

D ll 

D 

O 

K 

10 

0 

TJ 

> 

E 

a 

u 

60 

50 

40 

D 

a 

c 

o 

o 

i. *-. 

c 

•» 

o 

C 

o 

o 

30 

20 

D 

10 

a 

+ 

A - 1 

B - 1 

C-1 I D-2 I EMI 

D - 1 D- 3 

SCRUBBERS 

D 

~A'A 

F- 1 C I 

II t 

II I 

H 

L) HCl fc missions + Cl2 Emissium. 
P.9 

No information was available from MC 12 incinerator/scrubber 

installations on the amount of halogenated compound in the 

incinerator inlet or the amount of HCl and CI2 in the incinerator 

outlet. The incinerator inlet halogenated organic compound 

levels were therefore calculated based on the combustion of a 

model halogenated organic molecule and the reported scrubber 

outlet concentrations presented in Table 2. The model 

halogenated compound was developed by the EPA in a previous 

study.1 The concentration of the model compound at the entrance 

to the incinerator was estimated using stoichiometric balances 

and assuming the scrubber has a control efficiency of 99 percent 

for HCl and 95 percent for CI2 (see Appendix A.l for sample 

calculations). 

Table 3 presents the calculated inlet halogenated organic 

compound concentrations for the facilities in the database. The 

minimum inlet concentration for the incinerator/scrubber control 

systems was determined to be about 130 ppmvd for a scrubber only 

reporting HCl outlet emission levels, and about 160 ppmvd for a 

scrubber reporting both HCl and CI2 emissions. These 

calculations include simplifiying assumptions and are viewed as 

accurate to one significant figure. A value of roughly 100 ppmvd 

could be included in the regulations as the minimum concentration 

of total halogenated organic compounds entering an incinerator, 

boiler, or process heater that would require subsequent 

scrubbing. This approach was taken because the collected data 

support 99 percent removal for combustor/scrubber systems with 

scrubber outlet concentrations only within the range covered by 

the survey data, and applicability and performance of scrubbers 

to streams with outlet halogen levels below this range is 

uncertain. The regulation would also state the streams with 

halogenated organic concentrations above 100 ppmvd cannot be 

introduced to a flare. 

DonpaxhtmO*(Is) 
P.10 

Table 3. Model Halogenated Compound 

Concentrations for Surveyed 

Facilities 

CODE 

A 

B 

C 

D 

E 

F 

G 

H 

COMPANY 

BFGOODRICH 

BORDEN 

DOW 

DOW 

DOW 

OCCIDENTAL 

OCCIDENTAL 

PPG 

SCRUBBER 

NUMBER 

A-1 

B-1 

C-1 

D-l 

D-2 

D-3 

E-1 

F-l 

F-2 

G-1 

H-l 

H-2 

CALCULATED 

INCINERATOR 

INLET 

CONCENTRATION 

(ppmvd) 

164 

3,272 

ND 

10,238 

465 

7,612 

10,415 * 

3,639 * 

685 * 

132 * 

10,637 

9,071 

ND • no data 

* = values from HCl concentration only as 

chlorine was not provided. 
P.11 

Eight of the ten facilities in the database reported an HCl 

design removal efficiency of at least 99 percent with some as 

high as 99.9 percent. The remaining two reported 97 and 98 

percent efficiencies. A survey of gas absorber vendors also 

indicated that 99 percent control of HCl, HF, bromine (Br2) , and 

19~20 

Cl2 in gas streams is achievable. Based on this information, 

99 percent overall control of halogens and hydrogen halides from 

scrubbers would be achievable and could be included as a 

provision to the proposed standard. Halogen removal may be 

slightly lower than hydrogen halides, but halogen concentrations 

at scrubber inlets and outlets are generally expected to be lower 

than for hydrogen halides. 

5.0 MEASUREMENT TECHNIQUES 

In order to demonstrate 99 percent control, outlet 

concentrations from the scrubber as low as 0.8 ppmvd may need to 

be measured. (This value was reported for Cl2 at one of the 

facilities surveyed). A memorandum from Terry Harrison of the 

EPA, dated August 9, 1991,Z1 indicated that EPA Method 26 and 

proposed Method 26A are applicable for measurements at these 

levels. Both methods can be used to measure the following 

halogens and hydrogen halides: HCl, HF, hydrogen bromide (HBr), 

Cl2, and Br2. Method 26 is used for non-isokinetic sampling. 

Method 26A is applicable for isokinetic sampling. It is expected 

that some of the halogens and hydrogen halides exiting the 

scrubber will be entrained in moisture droplets. Therefore, 

isokinetic sampling using Method 26A is the recommended 

measurement method. However, Method 26A tends to show a bias for 

lower concentrations. The method is currently under review by 

the EPA to resolve these issues. 

The lower analytical detection limit of Method 26A is 

approximately 0.08 mg/dscm (see calculations in Attachment A.2). 

A standard factor of 5 times the detection limit results in an 

alternate lower cutoff of approximately 0.5 mg/dscm. If a 

facility can demonstrate an outlet concentration below 

monp«rh_mO* (la) 1 0 
0.5 mg/dscm for each halogen or hydrogen halide species present, 

the proposed regulation could specify that the facility would be 

considered to be in compliance and the inlet concentration would 

not have to be measured and percent reduction would not need to 

be calculated. This alternate concentration level is needed 

because facilities can not reliably measure concentrations below 

0.5 mg/dscm. 

6.0 SCRUBBER MONITORING PARAMETERS AND LIMITS 

The appropriate monitoring parameters to ensure scrubber 

compliance with the standard are the pH of the effluent from the 

last scrubber stage, and the liquid-to-gas (L/G) ratio. 

The pH of the effluent from the last scrubber stage is an 

indicator of its acidity (i.e., amount of acid gas dissolved). 

If the pH is lower than normal, the scrubber is unlikely to be 

removing sufficient acid in the gas to operate at the specified 

efficiency or to meet the proposed regulation. The pH value 

necessary to achieve performance requirements can be determined 

by operating at the maximum halogen mass flow rate during the 

initial performance test. During subsequent operation, the 

average pH should be maintained at a level not less than 1 pH 

unit below the value measured during the performance test. The 

average operating pH values would be determined during 3-hour 

measurement periods. This 3-hour averaging period is consistent 

with the averaging period used for all of the other process vent, 

combustion, and recovery device monitoring parameters in the 

proposed HON regulation. The pH can be monitored using a 

monitoring device with a continuous recorder, which are readily 

available from vendors. 

Monitoring the pH alone will not adequately indicate whether 

the scrubber is operating properly to meet the proposed 

regulation. For example, a pH change may also indicate the gas 

flow rate is smaller or larger than at normal operating 

conditions. The pH could be within the proposed limits, but the 

acid gas control efficiency of the scrubber could be reduced if 

the liquid-to-gas contact within the scrubber is below normal 

levels. Therefore, the L/G ratio should also be monitored. 

Decreased L/G values indicate a smaller liquid or larger gas flow 

-»np»rhtmO*(l») 1 1 
P.13 

rate, with a resultant decline in performance. At maximum 

operating load (i.e., when G is large), the L/G ratio tends 

toward a minimum value. The minimum L/G ratio necessary to 

achieve the performance requirements should be set as a limiting 

parameter. The L/G value would be determined during the 

performance test while the process unit is operating at minimum 

liquid flow and maximum gas flow rates and achieving 99 percent 

removal. The scrubber would then be required to monitor L/G and 

report any 3-hour period when the average L/G is more than 

5 percent below the average value measured during the performance 

test. The liquid and gas flow rates can be measured using 

continuous flow meters which are available from vendors. The 

flow meters would be installed at the gas and liquid inlets to 

the scrubber. 

monp«xhtm04(_s) 12 
P.14 

7.0 REFERENCES 

1. Questionnaire response from Gustafson, David, Dow Chemical, 

Midland, MI, to Oommen, R.V., Radian. May 22, 1991. Fax of 

response to questions concerning scrubber exit 

concentrations. 

2. Questionnaire response from Gustafson, David, Dow Chemical, 

Midland, MI to Oommen, R.V., Radian. May l, 1991. Fax of 

questionnaire on parameters of scrubber exit gas. 

3. Questionnaire response from Gustafson, David, Dow Chemical, 

Midland, MI, to Oommen, R.V., Radian. April 26, 1991. Fax of 

response to questions concerning parameters of the scrubber 

exit gas. 

4. Questionnaire response from Arnold, Sherrie, Dow Chemical, 

Midland, MI to Oommen, R.V., Radian. March 26, 1991. Fax of 

questionnaire on control technologies used to treat process 

vent streams. 

5. Questionnaire response from Emery, Elizabeth, Borden 

Chemicals and Plastics, Geismar, LA, to Oommen, R.V., 

Radian. May 2, 1991. Fax of questionnaire on parameters of 

scrubber exit gas. 

6. Questionnaire response from Emery, Elizabeth, Borden 

Chemicals and Plastics, Geismer, LA, to Oommen, R.V., 

Radian. April 1, 1991. Fax of questionnaire on control 

technologies used to treat process vent streams. 

7. Questionnaire response from Hinson, David, BF Goodrich 

Intermediates, La Porte, TX, to Oommen, R.V., Radian. April 

30, 1991. Fax of incinerator and stack data. 

8. Questionnaire response from Hinson, David, BF Goodrich 

Intermediates, La Porte, TX to Oommen, R.V., Radian. April 

2, 1991. Fax of questionnaire on control technologies used 

to treat process vent streams. 

9. Telecon. Oommen, R.V., Radian with Liggio, Esther, PPG, 

Environmental Engineer, May 10, 1991. Telecon about scrubber 

exit gas parameters. 

10. Questionnaire response from Liggio, Esther, PPG Chemicals, 

Lake Charles, LA, to Oommen, R.V., Radian, May 8, 1991. Fax 

of questionnaire on control technologies used to treat 

process vent emissions. 

11. Letter from Ewen, Kelly, Occidental Chemical Corporation, 

Convent, LA, to Oommen, R.V., Radian. April 24, 1991, Letter 

concerning parameters of scrubber exit gas. 

monparhtmO * (Is) 1 3 
P.15 

12. Telecon. Wilson, Jim, Occidental Chemical Co., Corpus 

Christi, TX, with Oommen, R.V., Radian, April 22, 1991, 

Telecon of response to questions about scrubber exit gas 

parameters. 

13. Questionnaire response from Takacs, Lazlo, Occidental 

Chemical Center, Niagara Falls, NY, to Oommen, R.V., Radian. 

March 26, 1991. Fax of questionnaire on control technologies 

used to treat process vent streams. 

14. Telecon. Oommen, R.V., Radian, with Home, Karen, Texas Air 

Control Board. May 15, 1991. Telecon on flare use. 

15. Telecon. Oommen, R.V., Radian, with Olsen, Karen, Texas Air 

Control Board. April 25, 1991. Telecon on flare use. 

16. Telecon. Disorbo, S., Radian, with Saitas, J., Texas Air 

Control Board. April 26, 1991. Telecon on flare use. 

17. Telecon. Oommen, R.V., Radian, with Davis, B., Louisiana 

Air Control Board. May 17, 1991. Telecon on flare use. 

18. Organic Chemical Manufacturing Volume 4: Combustion Control 

Devices, EPA-450/3-80-026. Office of Air Quality Planning 

and Standards, U.S. Environmental Protection Agency. 

19. Airpol, Inc., Peterboro, NJ, Bulletin PT/89-5M, 1991. 

20. Midwest Air Products, Co. Inc., Onosso, MI, Product Catalog, 

1991. 

21. Memorandum from Harrison, Terry, EMB/EPA to Oommen, R.V.. 

Radian. August 9, 1991, Fax of applicable test methods for 

measuring halogens from scrubbers. 

m«np»rhtm0* (Is) 1 4 
P.16 

APPENDIX A 

A.l SAMPLE CALCULATION FOR MODEL HALOGENATED COMPOUND 

CONCENTRATIONS AT THE INCINERATOR INLET 

A.2 CALCULATION OF METHOD 26A DETECTION LIMIT 

monptrhtaOM-s) 
P.17 

A.l SAMPLE CALCULATION 
P.18 

A.l SAMPLE CALCULATION OF THE MODEL HALOGENATED COMPOUND 

CONCENTRATION AT THE INCINERATOR INLET 

PURPOSE: The objective of this section is to present example 

calculations for estimating the halogenated organic 

compound concentration entering an incinerator that 

correlates to specific scrubber outlet HCl and CI2 

concentrations. 

FLOW DIAGRAM: The basic block flow diagram of the pollution 

control system is represented as: 

Waste Stream (W) 

Incinerator 

Effluent 

Stream 1 

(Ei) 

Scrubber 

Effluent 

Stream 2 

(E2) 

> 

The scrubber is assumed to be 99 percent efficient for 

HCl control, and 95 percent efficient for CI2 control 

based on the information collected and gas absorber 

vendor surveys. 

PROCEDURE: 

Since the only information known is the HCl and CI2 scrubber 

outlet concentrations, the following procedures will be used. 

1. From pollutant concentrations in E2 and removal 

efficiencies, pollutant concentrations in E^ will be 

calculated. 

2. From pollutant concentrations in Ei and stoichiometric 

balances, the halogenated organic compound 

concentration of W will be calculated, taking into 

account dilution air requirements. 

sampctlchtmO* (Is) A. 1-1 
P.19 

A.1.1 CALCULATION OF MODEL HALOGENATED ORGANIC COMPOUND 

A previous EPA project established a model halogenated VOC 

molecule with the following composition:" 

by weight percent 34.3% Carbon 

4.7% Hydrogen 

60.6% Chlorine 

To convert to moles, assume 100 lb basis: 

Carbon: 34.3 lb • } * TM°\* - 2.86 lb mole 

12.01 lb 

Hydrogen: 4.7 lb lb mole 

1.008 lb 

- 4.66 lb moles 

Chlorine: 60.6 lb lb mole 

35.5 lb - 1.71 lb moles 

c2.86 H4.66 cl1.71 

"Organic Chemical Manufacturing Volume 4: Combustion 

Control Devices, EPA-450/3-80-026. Office of Air Quality 

Planning and Standards, U.S. Environmental Protection Agency. 

s«_pc«lehtm0*(ls) A. 1-2 
A.1.2 CALCULATION OF HALOGENATED ORGANIC COMPOUND CONCENTRATION 

IN WASTE STREAM (W) 

Example Case: Inlet to incinerator = 0% oxygen in waste stream 

(W) 

Outlet from scrubber =3 % oxygen in Effluent 

(dry basis) stream 2 (E2) 

An example calculation will be presented using scrubber outlet 

data from the B.F. Goodrich facility (see Table 2 in the 

memorandum). 

HCl concentration = .93 ppmvd 

CI2 concentration = .75 ppmvd 

The concentration values are converted to mole % values using the 

equation: 

mole percent = (100) x ppmvd 

IO6 

Therefore: 

HCl mole percent = (100) (___93) = 9.3 x IO"5 

IO6 

Cl2 mole percent = (100) (.751 = 7.5 x IO"5 

10© 

Part 1: Calculation of Effluent Stream 1 (E^l 

The dry composition of E2 is comprised of HCl, CI2, O2, N2, 

CO2, and some inert compound. Assume E2 = 100 lb mole dry basis. 

If stream E2 contains 3% O2 then it would have 3 lb-moles of O2 

(100 lb-moles x .03) in it. The stream entering the scrubber is 

calculated from the following balance. 

smpca.ehtaOt(-s) A . 1 — 3 
P.21 

Assuming 99 % efficiency for HCl: 

*E2 

HCl, 

El . _efficiency 

100 

HCl 

1 -

E2 _, 9.3 x 10 

99 .01 0093 lb moles 

100 

Where

 XE2 is the concentration of a halogenated species in stream 

E2 and X^ is the concentration of the halogenated species in Ej_.' 

Assuming 95 % efficiency for CI2: 

Cl. 

Cl2 E2. 

1 -

95 

100 

7.5 x 10 

.05 

-5 

0015 lb moles 

Ex + z 

HCl «- .0093 lb moles 

CI2 ~ .0015 lb moles 

Inerts = w lb moles — > 

CO2 == x lb moles 

N2 = y lb moles 

Q.2 = 3 lb moles 

water = z lb-moles 

Scrubber 

99% HCl 

95% Cl2 

E2 + Z 

HCl = 9.3 x 10~5lb moles 

Cl2 = 7.5 x IO-5 lb moles 

— > Inerts = w lb moles 

CO2

 a x lb moles 

N2 = y lb moles 

02 • 3 lb moles 

water = z lb moles 

Assume CO2- N2, and O2 do not change across the scrubber. 

sampcalchtaO*<Is) A. 1-4 
P.22 

Example Case: (Continued) 

Part 2: Calculation of halogenated organic compound 

concentration in waste stream (W. 

The following diagram presents the flow streams entering and 

exiting the incinerator: 

Fuel (CH4) Theoretical air 

W 

c2.86 H4 .6 6 C1J..7! 

+ Inerts (Assume N2) 

i i 

Incinerator 

Ex + Z 

Dilution Air 

HCl = .0093 lb moles 

CI2 = .0015 lb moles 

Inerts = w lb moles 

CO2

 a x lb moles 

N2 = y lb moles 

0; =- 3 lb moles 

Water = z lb moles 

The concentration of the halogenated molecule entering the 

incinerator in stream W will be calculated from the stoichiometry 

of the combustion of the halogenated molecule and fuel, and the 

subsequent enthalpy balance. 

(1) Stoichiometry of Halogenated Organic Compound Combustion 

(Assume complete combustion) 

.0072 C2.86

 H4.66 cl1.71 _ > -0 1 2 H 2° -0093 HCl + .0015 Cl2 + 

+ -027 02 ' * .021 C02 

The theoretical O2, theoretical air, nitrogen in theoretical air, 

dilution air, and moisture in theoretical air and dilution air 

need to be calculated. 

1. Theoretical O2 needed = [(moles H2O) (Oxygen atoms in H2O) 

+ (Moles CO2) (Oxygen atoms in CO2)]/Oxygen atoms in O2 

= [(.012) + 2(0.021)]/2 - 0.027 lb moles 02 

2.. Theoretical air = Theoretical 02/Fraction of O2 in Air 

= [0.027 moles O2/.2I] = .129 lb moles air 

3. Nitrogen in theoretical air 

= (Theoretical air) (fraction of N2 in air) 

• (.129) (.79) - .102 lb moles N2 

4. Dilution air required = Excess 02/Fraction of O2 in air 

= [3 lb moles excess 02/.21] = 14.3 lb moles 

sampcslchtmO*(Is) A. 1-5 
P.23 

5. Moisture in theoretical air (assume air is saturated at 

77°F) 

= .013 lbs moisture/lb dry air." 

Moisture = .129 lb moles air * (29.1 lb air/lb mole air)* 

.013 lb water/lb dry air * (lb mole water/18 lbs) 

= .003 lb moles water 

6.. Moisture in dilution air (assume air is saturated at 77°F) 

= .013 lbs moisture/lb dry air. 

Moisture = 14.3 lb moles air * (29.1 lb air/lb mole air)* 

.013 lb water/lb dry air * (lb mole water/18 lbs) 

= .3 lb moles water 

(2) Stoichiometry of Fuel Combustion 

(Assume methane is fuel) 

See step (1) for formulas used. 

o CH4 + 2a 02 — > a C02 + 2a H20 

where a = moles of CH4 

1, Theoretical O2 needed = 2a lb moles 

2.. Theoretical Air = 2a/.21 - 9.52a lb moles 

3. Nitrogen in theoretical air = 7.52 a lb moles 

4. Moisture in theoretical air (assume air is saturated at 

77°F) 

= .013 lbs moisture/lb dry air. 

Moisture = 9.52 a lb moles air * (29.1 lb air/lb mole air)* 

.013 lb water/lb dry air * (lb mole water/18 lbs) 

= .2 a lb moles water 

(3) Enthalpy Balance 

An enthalpy balance is required to estimate the value of a 

• Assume heat release from the combustion of the model 

compound is insignificant. 

• Incinerator operating temperature = 2,000°F (based on HON 

incinerator parameters) 

Reference temperature = 77°F 

Heat of combustion of CH4 = Heat gain by the products of 

combustion 

"Felder, R.M. and Rousseau, R.W. Elementary Principles of 

Chemical Processes. Second Edition. 1986. John Wiley and Sons. 

sampealehtmOtda) A . 1 — 6 
P.24 

a H CH4 = (MCpAT)C 0 2 + (MCpAT)H o + (MCpAT>N2 theoretical 

+ (MCpAT)N2 

excess air 

(MCpAT)o2 

excess air 

+ (MCpAT)inerts 

where: 

HCH4 = Heat of combustion of methane = 23,875 Btu/lba 

M W CH4 = 1 6 lb/lb mole 

M = moles of each compound listed in incinerator exhaust from 

combusting CH4 and model VOC molecule. 

AT = Incinerator temperature minus reference temperature 

(2000-77) 

c p = Heat capacity of the products of combustion listed 

Heat Capacity of Compoundsb 

Pollutant Heat Capacity Coefficients Cp 

abe d (Btu/lb mole°F)c 

C02 36.11 4.233 -2.887 7.464 

H?0 33.46 .688 .7604 -3.593 

N2', Theoretical 29.00 .220 .5723 -2.871 

N;>, excess air 29.00 .220 .5723 -2.871 

0;>, excess air 29.10 1.158 -.606 1.311 

Inerts (assume N2) 29.00 .220 .5723 -2.871 

13.77 

10.84 

8.24 

8.24 

8.65 

8.24 

aCRC Handbook of Applied Engineering Science. 1970. Cleveland 

Rubber CO., Press. 

DFelder and Rousseau. Elementary Principles of Chemical 

Processes. Second Edition. 1986. John Wiley and Sons. 

cCalculated using the equation a + b*10_2T + c*10"5T2 + d*10~9T3 

(where T is in Celsius) to calculate heat capacity values in 

(J/gmol °C). The resulting values were multiplied by a factor 

of .238846 to convert to (Btu/lbmole °F). 

_i__->c»_chtm0*(-«) A. 1-7 
P.25 

Moles of Each Pollutant in Product (M) 

From Steps (1) and (2) 

co2 = <x + 0.21 

H20 = 2 « + .2 « + .012 + .003 + .3 

N2, Theoretical = 7.52 a + .102 

°2, excess = 3 

N2, excess = 11.3 of stream E2 

Use 100 lb-mole dry basis of stream E2 for estimating moles 

of inerts in products 

Inerts = 100-a-.021-7.52 «-.102-3-11.3 

After substituting values for AT, HCH4»

 MWCH4» and M, the 

following equation needs to be solved. 

o: (16 lb/lbmole) (23,875 Btu/lb) = 

(oc + .021) (13.77 Btu/lbmol °F) (2000 - 77) 

+ (2oe + .2« + .012 + .003 + .3) (10.84 Btu/lbmol°F) (2000 - 77) 

+ (7.52 « + .102)(8.24 Btu/lbmole °F) (2000 - 77) 

+ (3 lb moles) (8.65 Btu/lbmoles °F) (2000 - 77) 

+ (11.3 lbmoles) (8.24 Btu/lbmoles°F) (2000 - 77) 

+ (100 - « - .021 - 7.52 a - ,102 - 3 - 11.3) (8.24) (2000 - 77) 

Simplifying results in: 

382,000 a - (a + .021) (26,480) + (2.2a + .315) (20,845) 

+ (7.52 a + .102) (15,846) +. 49,902 

+ 179,060 + (85.56 - 8.52a) (15,846) 

325,507 a = 1,593,484 

Solving for a leads to: 

a = 4.90 

sampcalchtmOtds) A . 1 — 8 
(4) Determining the composition of stream E2 

The stream exiting scrubber (E2) has the following composition on 

a 100 lb mole dry basis: 

HCl = 9.3 x IO-5 lb moles 

Cl2 = 7.5 x IO""5 lb moles 

CO2, Halogen = .021 lb moles 

CO2, Fuel = a = 4.9 lb moles 

N2, Theoretical, Halogen = -

1 0 2 lb moles 

N2, Theoretical, Fuel = 7.52 a = 36.85 lb moles 

02, Excess Air = 3 lb moles 

N2, Excess Air = 11.3 lb moles 

Total =56.19 

However, stream E2 must have 100 lb-moles on a dry basis. 

Therefore, 100-56.19 or 43.81 lb-moles of some inert (assume N2) 

must be in stream E2 

(5) Determining the concentration of the VOC molecule in stream W 

Assuming the quantity of inerts does not change across the 

scrubber and incinerator, the waste stream must have the 

following composition: 

Halogenated model molecule = 0.0072 lb moles (Step (1)) 

Inerts (N2) 43.81 lb moles (Step (4)) 

Concentration of y (ppmv) = 

y (lb-moles) 

sum of components(lb-moles) 

x (1 x 10' 

Concentration of VOC .0072 

43.81 + .0072 

x (1 x 106) » 164 ppmvd » 160 ppmvd 

s___pc»_ehta.O*(l») A. 1-9 
P.27 

A.2 CALCULATION OF METHOD 26A DETECTION LIMIT 
P.28 

APPENDIX A.2 

CALCULATION OF METHOD 26A DETECTION LIMIT 

Method 2 6A 

Analytical Detection Limit: 0.1 nq/ml 

The sampling detection limit will be calculated from the 

analytical detection limit and the formulas presented in the 

calculational procedures section of the Test Method. 

The concentration of the halogenated molecule being sampled is 

calculated from the equation: 

(1) c = km/Vmstd 

where: c = concentration of halogenated molecule, mg/dscm 

k - 10"3 mq/nq 

m = /xg HCl in sample (see step 2) 

vm,std ~ meter box sampling volume at standard 

conditions, dscm 

(2) m = 1.028 SVs 

where: m = nq HCl in the sample 

S = concentration of sample, /*g Cl~/ml (use the 

analytical detection limit, 0.1 /xg/ml) 

Vs = volume of filtered and diluted sample, ml 

(assume 1000 ml) 

m = 1.028 X 0.1 X 1000 = 102.8 fiq. 

(3) vm std is calculated using the following equation: 

Vm,std - (t) (Q) 

where: t = sampling time.minutes 

Q = meter box sampling rate, liters/minute 

Assume the meter box is at standard conditions (1 atm, 68° F), 

and the stack exit gas is being sampled for 60 minutes at 21 

liters/min. 

monparhtm04(_s) A . 2 — 1 
P.29 

3 

Vm,std = (60) (21) —-— r =1.26 dscm 

1000 1 

The concentration is then 

c = (10~3) (102-8) _. Q Q8 2 mg/dscm 

1.26 

In this case the concentration is also the sampling detection 

limit. A value of 5 times the detection limit is: 

5 x Detection limit = (0.082) (5) = .410 - .5 mg/dscm 

nonpaxhtm04(ls) A. 2—2 
P.30 

ADDENDUM A 
P.31 

HALOGENATED STREAM DEFINITION 

The conversion of ppmvd of halogenated molecule to ppmvd of halogen atoms is 

based on the model molecule as follows: 

Model molecule = C2.86 H4.66 CI171 

There are 1.71 moles of Cl atoms per mole of model molecule. At atmospheric 

conditions, volume fraction (ppmvd) is equivalent to a mole fraction (moles 

halogen/mole vent stream). The lowest calculated value for CI2 and HCl is 164 ppmvd. 

The lowest calculated value for HCl only is 132 ppmvd (see Table 3). 

132 ppmvd x A = 225.7 ppmvd Cl atoms. 

mole model 

164 ppmvd x

 1J 1 mole ° = 280.4 ppmvd Cl atoms, 

mole model