Pilot-Scale Air Toxics R&D Assessment of Creosote-Treated and PCPTreated Wood Cofiring for Pulverized Coal Utility Boiler Applications

M.C. Freeman1,*, W.J. O’Dowd1, T.D. Brown1, R.A. Hargis, Jr.1, R. A. James1, S. I.

Plasynski1, G.F. Walbert2, A.F. Lowe3, and J.J. Battista, Jr.4

1

 U.S. Department of Energy, National Energy Technology Laboratory, Pittsburgh,

Pennsylvania, USA

2

 Parsons Infrastructure & Technology Group, Inc., Library, Pennsylvania, USA

3

 Entropy, Inc., Raleigh, North Carolina, USA

4

 Cofiring Alternatives, Ebensburg, Pennsylvania, USA

6

 U.S. Department of Energy, Washington, D.C., USA

* Corresponding Author. Tel.: + 1-412-386-6094 fax: + 1-412-386-4806

E-mail address: mfreeman@netl.doe.gov (M.C. Freeman)

ABSTRACT

This paper presents air toxics emissions test results from a pilot-scale cofiring study of

pentachlorophenol- (PCP) and creosote-treated woods to provide data for pre-permitting

requirements for utilities interested in biomass cofiring as a means of increasing

renewable energy while reducing greenhouse gases and other emissions for pulverized

coal-fired utility boilers. These PCP/creosote-treated wood cofiring tests included a

comprehensive assessment of air toxics, including dioxins, furans, polycyclic aromatic

hydrocarbons (PAH), heavy metals (Hg, Sb, As, Cd, Cr, Co, Pb, Ni, and Se),

formaldehyde and other volatile organic compounds, HCl, and particulates. This

pilot-scale testing measured ‘uncontrolled’ emissions from the combustor (upstream of

flue gas cleanup devices) and showed that PCP/creosote-treated wood could be

successfully cofired at 10% heat input without increases in air toxic emissions as

compared to a baseline eastern bituminous coal. Air toxics emissions were typically very

low, and often near or below detection limits, largely as a result of the good air/fuel

mixing and high furnace temperatures associated with pulverized coal combustion. One

expected result was an increase in uncontrolled HCl emissions as a result of the higher

chlorine content in the treated woods, although even at 10% cofiring levels, HCl

emissions were within the range of other U.S. coals. This paper is presented to provide

independent data that industry, environmental groups, and regulators may consider in

evaluating the opportunities for treated wood cofiring test burns and commercialization in

full-scale coal-fired boilers in an environmentally acceptable manner.

Key words: Biomass Cofiring; Pulverized Coal; Chemically-Treated Woods; Air Toxics

Emissions

1. Introduction
Biomass cofiring in large industrial and utility coal-fired boilers is a practical, attractive

approach for increasing renewable energy, particularly given the wide availability,

existing capital investment, and performance of coal-fired boilers for providing efficient,

low-cost power [1-10]. Biomass cofiring activities at the U.S. Department of Energy

(DOE), National Energy Technology Laboratory (NETL), and other organizations have

been driven by the diverse interests of biomass stakeholders and coal-fired utilities in

anticipation of the possibility of future regulations in global climate change or renewable

energy portfolio standards. Other utility interests include green pricing programs,

helping industrial customers solve waste problems, assisting regional development in

rural and urban areas, and evaluating biomass cofiring as part of an overall strategy to

decrease costs, add capacity, or help achieve SO2/NOx emissions compliance. Although

some utility cofiring is successfully practiced in the U.S. and abroad, establishing long

term reliability and improving economics through process optimization are still

significant needs. Major issues include biomass fuel handling equipment as well as

fireside impacts, such as carbon burn-out, ash fouling, ash disposal, emissions, and other

factors that influence overall plant integration, availability, efficiency, and cost that often

are site-specific and vary significantly. For these reasons, cofiring must be underpinned

by coal-fired utilities and innovative partnering with biomass fuel providers to offer

multiple benefits to reduce risk and address stringent environmental regulations under an

increasingly cost competitive environment brought about by utility deregulation.

Many treated woods, such as telephone poles, transmission poles, and railroad ties are a

potentially attractive renewable fuel for cofiring given their typically very low moisture

(< 10%), sulfur (< 0.3%), nitrogen (< 0.4%), and ash (< 2%) contents as well as high

heating value (over 21 kJ/g, over 9000 Btu/lb) and bulk density compared to other

biomass fuels. Such treated woods are readily available with millions of tons across the

U.S., and often have very high landfill disposal costs (e.g., up to $80/ton) to utilities and

other industries. Increasingly, landfills in certain regions are considering the possibility

of turning away such treated woods.

In some respects, treated woods offer a significant opportunity relative to premium lowcost biomass feedstocks, such as lumbermill sawdusts. While lumbermill sawdusts are

also favorably low in sulfur, nitrogen, and ash content, they typically have low heating

values (due to higher moisture) and low densities that are important in terms of the cost

of delivery, storage, and handling. While competition for lumbermill sawdust and other

biomass residues may drive a local market where utilities might be expected to pay $10-

20/tonne or more, the high landfill costs of treated woods could enable even more

favorable economics. For example, cofiring treated woods as part of utility generated

waste (e.g., spools, cross arms) could reduce out-of-pocket landfill costs while helping

local industries and customers deal more economically with treated wood waste disposal

issues. Thus, coal-fired utilities could consider cofiring treated woods along with other

biomass fuels such as sawdusts and urban wood wastes to reduce power generation costs

while utilizing renewable energy and reducing emissions of greenhouse gases. Of course,

a key barrier is showing the environmental viability of treated wood fuel cofiring from a

permitting perspective.
Of particular concern is the presence of PCP and creosote chemicals used for wood

preservation. Utilities, environmental groups, and regulators need to be confident that

treated woods can be successfully cofired in coal-fired boilers without harmful air toxics

emissions, especially trace organics such as dioxins, furans, polycyclic aromatic

hydrocarbons (PAH), and formaldehyde. Thus, it was determined that a comprehensive

pilot-scale air toxics study for cofiring PCP/creosote-treated wood would be helpful to

address potential environmental concerns.

2. Experimental

PCP/creosote-treated wood cofiring tests were conducted in a state-of-the-art pilot-scale

Combustion and Environmental Research Facility (CERF) that has been designed for a

wide range of combustion and pollution control studies of most solid, liquid, and gaseous

fuels [11]. The CERF consists of various components as shown in Figure 1. Originally

built in 1989 to investigate the combustion properties of deeply-cleaned coals for

pulverized coal boiler applications, the CERF's capabilities have been continuously

expanded to support a wide range of combustion and environmental control R&D

projects. Specialized probes for gas/particulate sampling, temperature measurement, insitu flame viewing system, in-situ measurements of surface temperature and emissivity

have been developed along with various panels and probes for the study of ash

slagging/fouling behavior on tube surfaces at controlled metal temperatures. CERF

activities are complemented by other NETL R&D facilities for fuel processing,

combustion, and emissions studies, as well as 3-Dimensional Computational Fluid

Dynamics (CFD) modeling. Typically, the CERF R&D involves outside parties that bring

fuels, concepts, or materials for evaluation. For example, the CERF has served as a host

site for high-temperature exposures of over sixty ceramic and alloy samples from

researchers at other DOE national laboratories, universities, and industry manufacturers

in support of advanced power systems under development. Cooperative efforts with U.S.

industry have evaluated novel NOx control processes using the CERF. Over twenty coals

from the U.S., as well as from India, Russia, Ukraine, and Indonesia have been tested.

The CERF has cofired various biomass fuels, such as lumbermill sawdust, furniture waste

sawdust, pallets, nonrecyclable paper, cow manure, switchgrass, and hybrid willow.

In planning the CERF treated wood cofiring tests, input from numerous organizations

was obtained, including various utilities and the Electric Power Research Institute, as

well as local and state regulators from the Allegheny County Health Department and

State of Pennsylvania Department of Environmental Protection. This input helped

specify CERF test conditions and comprehensive air toxics sampling along with QA/QC

measures to improve data quality in conjunction with NETL’s extensive air toxics

experience in assessing mercury and other hazardous air pollutants (HAPs) from coalfired boilers over the last decade. This diverse organizational participation resulted in a

cofiring test program that included an assessment of dioxins, furans, polycyclic aromatic

hydrocarbons (PAH), heavy metals (e.g., mercury, antimony, arsenic, cadmium,

chromium, cobalt, lead, manganese, nickel, and selenium), formaldehyde and other
aldehydes, ketones, other organic volatile compounds, total hydrocarbons, hydrogen

chloride, and particulates.

CERF tests were conducted using a baseline Upper Freeport bituminous coal with 10%

cofiring (energy basis) with PCP-treated and creosote-treated wood. Although 10%

cofiring is higher than what some utilities envision for treated wood cofiring (e.g., 5%

heat input or less) based on expected day-to-day biomass resource availability and

practical need for multiple biomass feedstocks, this 10% level allowed a more stringent

assessment of potential air toxics issues.

The CERF testing focused on measuring ‘uncontrolled’ emissions from the combustor

(upstream of the baghouse) in an effort to directly evaluate differences between the

baseline coal and treated wood cofiring cases. Three sampling ports were installed at the

baghouse inlet to enable isokinetic single-point sampling using standard probes. These

sampling ports consisted of a series of 3-inch tees in the CERF’s 3-inch schedule-10

stainless steel flue gas piping section that was also heavily heat traced with temperature

controllers to maintain the sampling locations near 150 C (300 F).

Specific protocols for air toxics sampling that were followed included EPA Method 23

(dioxins/furans and PAH), Method 25A (total hydrocarbons), Method 26A (particulate

matter and HCl), Method 29 (metal HAPs), Method SW-846 M0011 (aldehydes and

ketones), and Method SW-846 M0030 (volatile organics sampling train). Conventional

procedures were followed for method blanks, field blanks, etc. in the approved QA/QC

sampling plan while additional measures, such as blind external audit samples and

additional analyses for sample recovery determinations, were incorporated to improve

data quality and provide more insight. Major flue gas components were continuously

monitored downstream of the 3-isokinetic sampling locations using standard process gas

analyzers for SO2 (infrared), NOx (chemiluminescent), CO (infrared), O2 (paramagnetic),

and CO2 (infrared) emissions using a sintered metal filter and ice bath sample

conditioning system.

Utility-grade Upper Freeport coal was obtained and pulverized to normal pc grind

specifications of less than 2% plus 50-mesh and about 70% minus 74-micron (200-mesh)

using a hammermill. The pulverized coal product drums were carefully sampled,

analyzed, and used so that the variation in particle size (minus 74-micron), ash content,

and other properties were minimized for baseline coal and subsequent treated wood/coal

blend testing for the air toxics study.

Whereas the standards for coal particle size distribution for pc combustion are very well

established, biomass particle sizing for cofiring applications is site-specific due to the

influence of many factors. Boiler temperature/flow profiles, biomass injection location,

and biomass fuel variability, such as particle density, moisture, aspect ratio, and chemical

composition (volatile matter and char characteristics) that play a key role in establishing

biomass combustion behavior relative to the achievable residence times for coarser

biomass particles. In recognition of the differing residence times and flow behavior

between pulverized coal and biomass particles, 3-dimensional computational fluid
dynamics (CFD) modeling studies are also being conducted to address scalability issues

[12].

PCP-treated and creosote-treated telephone poles were initially processed with a

conventional wood chipper to about 3-inch chunks before further size reduction using a

prototype collision mill by Mesa Reduction Engineering and Processing, Inc. (MREP).

While this MREP processing would be more than sufficient for full-scale cofiring

applications, further size reduction was required based on preliminary CERF cofiring

tests. Because the CERF is down-fired with 3-m (9 ft) height and radiant furnace average

linear gas velocities of less than 2 m/sec, most biomass particles need to be finer than

about 1-mm (16-mesh) to prevent still-burning sparklers from entering the bottom ash

hopper and CERF convective section. In contrast, full-scale boilers are much taller than

pilot units, and commonly up-fired with furnace gas velocities over 10 m/sec (30 ft/sec),

allowing the potential for increased residence time. For example, biomass cofiring at

particle sizes up to about 6-mm (1⁄4-inch) have been shown in utility cofiring

demonstration tests and confirmed with biomass combustion modeling [4,10,13-14].

Recognizing the central point that each pulverized coal combustor will have a critical cutoff in terms of allowable biomass topsize and moisture, this study sought to conduct air

toxics assessments for cofiring at realistic combustion conditions without overgrinding

the treated woods.

3. Combustion Results & Discussion

Table 1 summarizes fuel analyses for the baseline Upper Freeport (a medium-volatile,

moderate-sulfur bituminous coal) along with the PCP- and creosote-treated woods. Of

note are the very low sulfur, nitrogen, and ash contents as well as high volatility of the

treated woods. Compared to many other biomass fuels, treated woods have much lower

moisture contents and much higher heating values, largely as a result of the chemical

treatments for wood preservation. Of note is that the treated woods actually have higher

heat contents than subbituminous coals (e.g., Powder River Basin) and other low rank

coals that are widely used for power generation.

Preliminary CERF cofiring tests were conducted to specifically assess the treated wood

particle size issue and the extent of size reduction required to ensure minimal sparklers

and increases in bottom ash or fly ash unburned carbon. In this manner, CERF testing

would be consistent with expected utility practices where biomass grinding specifications

would be based on avoiding troublesome sparklers and undesirable elevations in fly ash

loss-on-ignition. Final Pulva hammermill settings were established based on achieving

occasional sparklers during cofiring in conjunction with combustion profiles. Owing to

the greater difficulty in grinding, the PCP-treated wood resulted in a coarser distribution

than the creosote-treated wood under similar processing conditions with the Pulva

hammermill. Both fuels were finally processed to less than 1% minus 16-mesh, the

PCP-treated wood contained about 68% plus 50-mesh as compared to the creosotetreated wood that was about 35% plus 50-mesh.
Combustion profiles were established with high-volume particulate sampling at varying

distances (effectively representing different residence times) from the CERF burner to

help verify proper treated wood sizing. Table 2 shows typical combustion results

comparing loss-on-ignition (LOI) profiles for treated wood cofiring with baseline coal at

similar burner conditions. The CERF flame root position was determined by inserting a

thermocouple through the center of the burner and recording the standoff distance at

about 980 C (1800 F). As expected, the high volatility of the treated woods decreased the

flame root position during cofiring, resulting in earlier ignition as compared to the

baseline coal flame. In addition, LOI data confirmed that treated wood particles were

properly sized as indicated by the slightly improved combustion expected from cofiring a

low-ash, high-volatile biomass fuel.

4. Emissions Results & Discussion

CERF air toxics tests were conducted at about 110 kWt (370 kBtu/hr) with burner

settings and temperatures typical of pulverized coal combustors, to compare the baseline

Upper Freeport coal with 10% treated wood blends. These conditions included 20% total

excess air, secondary air swirl number of 0.5, primary air/secondary air ratio of about 0.2,

and a furnace exit gas temperature (FEGT) near 1100 C (2000 F). Three sets of tests

(sampling periods) were obtained and averaged for the various methods tabulated below.

Table 3 presents a summary of flue gas emissions data, averaged for each fuel during the

air toxics sampling periods. Of note are the reduced SO2 and NOx emissions when

cofiring the treated woods. These reductions are consistent with expectations and general

trends reported elsewhere, including various pilot-scale and utility biomass cofiring

projects [4,7,8,10,13]. Much of this reduction is due to the fact that the treated woods are

considerably lower in sulfur and nitrogen content as compared to the baseline coal as

shown in Table 1. In addition, the NOx emissions reductions are also consistent with the

high-volatility of the treated wood fuel coupled with the decreased flame root position

when cofiring.

Of importance is that both CO and total hydrocarbon (THC) emissions were reduced

during treated wood cofiring, although baseline CO levels were somewhat higher than

typical CERF testing. The CO emission results are consistent with achieving good

combustion during treated wood cofiring as also shown in preliminary CERF testing in

Table 2. Table 3 also reveals a reduction in particulate emissions during cofiring that is

consistent with the reduced ash loading of the treated woods as compared to the baseline

coal.

An expected result was an increase in uncontrolled hydrogen chloride (HCl) emissions as

a result of the higher chlorine content in the treated woods. While elevations in HCl are

very undesirable from the standpoint of corrosion on boiler tube surfaces, it is noteworthy

that even at 10% cofiring levels, HCl emissions were within the range of other U.S. coals.

Whereas the baseline Upper Freeport coal had an average chlorine content of 0.058 wt%,

several Illinois basin bituminous coals have chlorine contents in the 0.2-0.3 wt% range.

In terms of corrosion, it should be noted that while the treated woods are very low in ash
and alkali which is very benefical, the higher HCl emissions could be problematic if the

treated woods were used in combination with high-alkali biomass fuels (e.g., straws)

during cofiring, especially with higher-alkali coals or coal-fired boilers already exhibiting

corrosion and slagging/fouling difficulties. However, recent experimental studies have

reported that higher levels of flue gas SO2 (from the coal sulfur) and resultant tendency

for alkali sulfation reactions in preference to the more troublesome alkali chloride

formations in ash deposits during cofiring [13].

Table 4 summarizes aldehyde and ketone results on a part-per-billion (ppb) and emissions

factor (g/MJ) basis, and illustrates the encouraging results with treated wood cofiring

relative to the baseline coal. Of note are the very low levels of aldehydes and ketones

that were at or below the detection limits of just a few ppb. Average formaldehyde and

other aldehyde/ketone levels were barely detectable in the 0.2 to 3 ppbv (corrected to 3%

dry O2 basis) corresponding to equivalent, uncontrolled levels of less than 3.2E-07 to

2.4E-06 g/MJ based on detection limits.

Air toxics results for numerous compounds measured with the volatile organics sampling

train (VOST) were also favorable, with very low emissions levels observed with the

baseline coal and treated wood cofiring cases. One complication that did arise in the

analytical sample characterization was the presence of several polyalkylsiloxane

compounds attributable to the gasketing material used in the CERF.

Table 5 summarizes the uncontrolled emissions factors (g/MJ) for total polychlorinated

dibenzo-p-dioxin (PCCD), total polychlorinated dibenzofuran (PCDF), and polycyclic

aromatic hydrocarbons (PAH). These emissions levels were extremely low and show

very favorable results with treated wood cofiring emissions factors that were somewhat

lower than the baseline coal. These results are reinforced further upon examination of the

various 3-8 congeners of dioxin and furans, and individual PAH compounds that were

sampled as shown in Tables 6-8. For comparison, Tables 6-8 reports emissions in terms

of nanograms (for dioxin and furan) or micrograms (for PAH) per dry normal (20 C, 760

torr) cubic meter corrected to 3% O2. Of significance is that the vast majority of

compounds were ‘non detects’ and where quantification was possible, the treated wood

cofiring cases were typically somewhat lower than the baseline coal.

Table 9 summarizes uncontrolled emissions factors (g/MJ) for various heavy metals. As

expected, treated wood cofiring metal HAPs results were similar to the baseline coal,

wioth some metals showing very slightly higher or lower levels that may not be

statistically significant. Although the treated woods have a much lower ash loading as

compared to the baseline coal as shown in Table 1, the 10% treated cofiring levels did not

appear to significantly alter metal HAPs results.

The pilot-scale CERF results clearly indicate that treated woods can be successfully

cofired with pulverized coal from an environmental perspective. Because the above

results provide uncontrolled emissions comparisons, it is possible that treated wood

cofiring could be equally, if not more attractive, from a practical control standpoint. For

example, when considering that various pollution control technologies, such as wet
scrubbers, spray dryers, fabric filters, and electrostatic precipitators (for primary SO2,

NOx, and particulate control) also provide secondary benefits for removing some trace

pollutants`.

While treated wood cofiring offers the expected benefits of reduced sulfur, nitrogen

oxides, and particulates based on fuel composition, the CERF results provide

encouraging data relative to air toxics that could impact regulatory decisionmaking and

public acceptance. While coal-fired utility boilers are not presently regulated for heavy

metals and trace organics in the U.S., the U.S. Environmental Protection Agency (EPA)

and other organizations are looking closely at this issue. Consequently, considerable

efforts have been undertaken by NETL and others to better quantify and assess hazardous

air pollutants (HAPs) for coal-fired power plants [15-17]. The CERF baseline coal results

were generally consistent with air toxics data from coal-fired utility boilers in terms of

the very low, and often nondetectable, trace organics, including dioxin, furan, and PAH,

largely as the result of the high-temperatures and other characteristics of pulverized coal

flames that provide excellent combustion. Future work will evaluate these CERF results

in more detail and provide comparisons with available literature and address scalability

issues.

5. Summary

Pilot-scale cofiring studies were conducted to examine combustion and environmental

considerations with pentachlorophenol- (PCP) and creosote-treated woods. In addition to

reducing sulfur and nitrogen oxides as well as particulates, treated wood cofiring air

toxics data was very encourgaging. The test program showed extremely low levels (and

often, nondetectable) levels of dioxins, furans, polycyclic aromatic hydrocarbons (PAH),

heavy metals (e.g., mercury, antimony, arsenic, cadmium, chromium, cobalt, lead,

manganese, nickel, and selenium), formaldehyde and other aldehydes, ketones, numerous

organic volatile compounds, and total hydrocarbons.

Experimental results confirmed that PCP/creosote-treated wood could be successfully

cofired at 10% energy-basis without increases in air toxic emissions. In many instances,

the uncontrolled air toxics emissions factors for treated wood cofiring were actually

somewhat lower than the baseline pulverized coal testing. It is hoped that this pilot-scale

CERF air toxics data may help stakeholders deal with pre-permitting issues to allow

future full-scale test cofiring burns, and assist in the commercialization of PCP/creosotetreated wood cofiring in an environmentally acceptable manner.

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Acknowledgments

This project was funded by the DOE Office of Energy Efficiency and Renewable Energy

(EERE) Biomass Power Program and the DOE Office of Fossil Energy. The authors wish

to thank Clement Lacher, Jr. and Elias George of NETL, Jeffrey Palcic of Parsons,

Richard Conn of Foster Wheeler, and Thomas Dunder of Entropy for their contributions

to the project. In addition, the authors thank Bruce Fry and Rick Szekeres of the

Pennsylvania State Department of Environmental Protection, as well as Edwin Taylor of

the Allegheny County Health Department for their support and regulatory insights.

Disclaimer

Any reference in this paper to specific commercial products, processes, or services is to

facilitate understanding only and does not necessarily imply its endorsement or favoring

by the U.S. Department of Energy.
Figure 1. NETL Combustion and Environmental Research Facility

Table 1

Analyses of Upper Freeport Coal and Treated Wood Fuels

Upper Creosote PCP

Freeport Treated Treated

Coal Wood Wood

Proximate (wt%)

 Moisture 1.25 5.62 5.01

 Volatile Matter 21.85 83.54 88.40

 Fixed Carbon 61.42 9.56 6.02

 Ash 15.48 1.28 0.47

Higher Heating Value (MJ/kg) 29.81 21.47 21.94

Ash Content g/MJ 5.193 0.593 0.215

Sulfur Content g/MJ 0.567 0.069 0.073

Nitrogen Content g/MJ 0.421 0.103 0.030
Table 2

Combustion Profiles for Baseline Coal and Treated Wood Cofiring

Upper 10% 10%

Freeport Creosote PCP

Coal Wood Wood

Burnout Profile, % LOI Basis

Furnace Location

 Port 3 - 114 cm from burner 35.7 31.2 34.2

 Port 4 - 160 cm from burner 28.0 23.7 29.9

 Port 5 - 206 cm from burner 16.7 15.2 18.8

 Port 6 - 252 cm from burner 13.4 13.9 12.9

 Baghouse Inlet (Fly Ash) 11.1 9.0 8.3

Flame Root Position (cm) 10.9 8.4 8.9

Table 3

Flue Gas Emissions Results for Treated Wood Cofiring

10% 10%

 Baseline Creosote PCP

Flue Gas (dry basis @3%O2) UF Coal Wood Wood

 SO2 (ppm) 1209 1120 1102

 NOx (ppm) 574 474 496

 CO (ppm) 92 75 69

 HCl (ppm) 44 61 128

 Total Hydrocarbons (ppm) 2.0 1.6 1.5

 (expressed as propane)

 Particulate (g/dNm3) 8.9 5.5 6.9
Table 4

Aldehyde and Ketone Emissions Results, Average of 3 Tests

10% 10%

 Baseline Creosote PCP

UF Coal Wood Wood

Emissions Factor (g/MJ) Basis

Acetaldehyde < 8.12E-07 ~ 1.51E-06 < 7.42E-07

Acetophenone < 2.43E-06 < 1.81E-06 < 1.73E-06

Formaldehyde ~ 9.23E-07 9.41E-07 ~ 1.06E-06

Isophorone < 3.66E-07 < 3.19E-07 < 3.54E-07

Propionaldehyde < 4.01E-07 < 3.50E-07 < 3.87E-07

Flue Gas Composition (dry ppb @3% O2)

Acetaldehyde < 1.4 ~ 2.7 < 1.3

Acetophenone < 1.5 < 1.2 < 1.1

Formaldehyde ~ 2.3 2.4 ~ 2.6

Isophorone < 0.21 < 0.18 < 0.19

Propionaldehyde < 0.53 < 0.46 < 0.43

Notes: < indicates the value is below the detection limit

 ~ estimated value, indicates the measured value is below the

 quantitation limit or the measured value is above the calibration range

Table 5

Total Dioxin, Furan,and PAH Emissions Factor Results, Average of 3 Tests

10% 10%

 Baseline Creosote PCP

UF Coal Wood Wood

Total PCDD (g/MJ) 1.73E-11 2.57E-12 5.51E-12

Total PCDF (g/MJ) 7.32E-12 ND 1.33E-12

Total PCDD/PCDF (g/MJ) 2.46E-11 2.57E-12 6.84E-12

Total PAH (g/MJ) 4.21E-08 2.44E-08 ND
Table 6

Dioxin Results, Average of 3 Tests (ng/dNm3 @3%O2 )

10% 10%

 Baseline Creosote PCP

UF Coal Wood Wood

2,3,7,8-TCDD ND ND ND

Other TCDD ND ND ND

1,2,3,7,8-PeCCD ND ND ND

Other PeCCD 1.07E-02 4.38E-03 6.05E-03

1,2,3,4,7,8-HxCCD ND ND ND

1,2,3,6,7,8-HxCCD ND ND ND

1,2,3,7,8,9-HxCCD ND ND ND

Other HxCCD 7.84E-03 ND ND

1,2,3,4,6,7,8-HpCCD 1.09E-02 ND 1.97E-03

Other HpCCD 3.67E-03 ND 0.0

OCDD 2.25E-02 3.93E-03 9.43E-03

Total PCDD 5.56E-02 8.31E-03 1.74E-02

Table 7

Furan Results, Average of 3 Tests (ng/dNm3 @3%O2 )

10% 10%

 Baseline Creosote PCP

UF Coal Wood Wood

2,3,7,8-TCDF ND ND ND

Other TCDF ND ND ND

1,2,3,7,8-PeCDF ND ND ND

2,3,4,7,8-PeCDF ND ND ND

Other PeCDF 6.86E-03 ND 1.78E-03

1,2,3,4,7,8-HxCDF 6.72E-03 ND ND

1,2,3,6,7,8-HxCDF 9.40E-04 ND ND

1,2,3,7,8,9-HxCDF ND ND ND

2,3,4,6,7,8-HxCDF 5.24E-04 ND ND

Other HxCDF 3.19E-03 ND ND

1,2,3,4,6,7,8-HpCDF 5.24E-03 ND 2.41E-03

1,2,3,4,7,8,9-HpCDF ND ND ND

Other HpCDF ND ND ND

OCDF ND ND ND

Total PCDF 2.34E-02 ND 4.19E-03
Table 8

PAH Results, Average of 3 Tests (ug/dNm3 @3%O2 )

10% 10%

 Baseline Creosote PCP

UF Coal Wood Wood

Acenaphthene ND ND ND

Acenaphthylene ND ND ND

Anthracene ND ND ND

Benzo(a)anthracene ND ND ND

Benzo(b)fluoranthene ND ND ND

Benzo(k)fluoranthene ND ND ND

Benzo(g,h,i)perylene ND ND ND

Benzo(a)pyrene ND ND ND

2-Chloronaphthalene ND ND ND

Chrysene ND ND ND

Dibenz(a,h)anthracene ND ND ND

Fluoranthene ND ND ND

Fluorene ND ND ND

Indeno(1,2,3,-cd)pyrene ND ND ND

2-Methylnaphthalene 0.068 ND ND

Naphthalene 0.067 0.079 ND

Phenanthrene ND ND ND

Pyrene ND ND ND

Total PAHs 0.134 0.079 ND

Table 9

Heavy Metals Emissions Factors (g/MJ), Average of 3 Tests

10% 10%

 Baseline Creosote PCP

UF Coal Wood Wood

Antimony 7.36E-06 6.38E-06 8.26E-06

Arsenic 4.21E-04 3.42E-04 4.50E-04

Cadmium 5.84E-06 4.65E-06 6.36E-06

Cobalt 2.38E-04 1.14E-04 2.37E-04

Lead 1.34E-04 9.96E-05 1.47E-04

Manganese 1.17E-03 6.68E-04 1.17E-03

Mercury 9.18E-06 9.40E-06 8.29E-06

Nickel 2.01E-04 1.23E-04 1.49E-04

Selenium 6.61E-05 3.96E-05 5.55E-05