Organic Emissions from Pilot-Scale Incineration of CFCS

EPA/600/A-94/008
ORGANIC EMISSIONS FROM PILOT-SCALE INCINERATION OF CFCS
Jeffrey V. Ryan
Acurex Environmental Corporation
4915 Prospectus Drive
P.O. Box 13109
Research Triangle Park, NC 27709
C. W. Lee
U.S. Environmental Protection Agency
Air and Energy Engineering Research Laboratory
Research Triangle Park, NC 27711
Steven Kom
T-Thermal Inc.
Brook Road
Conshohocken, PA 19028
ABSTRACT
As a result of the Montreal Protocol, an international accord implemented to reduce the production and use of
stratospheric ozone depleting substances, considerable quantities of chlorofluorocarbons (CFCs) and halons may
be accumulated and may ultimately require disposal or destruction. Incineration is a potential destruction
technology; however, little is known of the combustion emission characteristics from incinerated CFCs. A study
has been performed that characterizes the organic emissions resulting from the pilot-scale incineration of
trichlorofluoromethaDe (CFC-11) and dichlorodifluoromethane (CFC-12) under varied feed concentrations. A
290 kW (1,000,000 Btu/h) incinerator was made available to the U.S. Environmental Protection Agency (EPA)
for these tests. The emissions characterizations focused on determining the destruction and removal efficiencies
(DREs) and major products of incomplete combustion (PICs) for each CFC evaluated. Sampling was performed
to screen for volatile and semivolatile organic emission products including chlorinated aliphatics, chlorobenzenes,
chlorophenols, polychlorinated dibenzodioxins and furans (PCDDs and PCDFs), and polyaromatic hydrocarbons
(PAHs). Results indicate that five nines (99.999 percent) DRE can be achieved at a CFC-11 feed concentration
as high as 69 percent by mass. The formation of volatile and semivolatile organic PICs was minimal. "Less
than" concentrations are presented for target analytes not detected. Total PCDD/PCDF emission concentrations
did not exceed 140 ng/m . The injection of water into the combustion zone may improve the thermal destruction
process.
INTRODUCTION
Halogenated hydrocarbons, such as chlorofluorocarbons (CFCs) and halons, have been implicated in the depletion
of stratospheric ozone. International accords are in place to phase out the production and/or use of these ozone-
depleting substances (ODSs) by the end of the century. Although some of these CFCs will be recycled, it may
be necessary to destroy substantial quantities of some CFCs to reduce current inventories. A United Nations
Environment Programme (UNEP) technical advisory committee was formed in 1991 to evaluate the most
appropriate ODS destruction technologies. Incineration was identified as a potentially viable CFC destruction
technology. However, the combustion emissions from CFC incineration have not been well characterized.
Characterization of products of incomplete combustion (PICs), in addition to determination of destruction and
removal efficiencies (DREs), is required to fully evaluate the viability of incineration as a CFC destruction
technology.
Relatively little information is available regarding CFC incineration, particularly in the area of PIC
characterization. Dickerman et al. collected data indicating that various CFCs have been destroyed effectively by
full-scale incineration.1 No data on PIC formation were included. The Air and Energy Engineering Research
Laboratory (AEERL) of the U.S. Environmental Protection Agency (EPA) initiated a program to evaluate the
viability of CFC incineration, including characterization of PICs. In support of this program, a bench-scale study
thai characterized the emissions from CFC-11 (irichlorofluoromeihane) and CFC-12 (dichlorodifluoromethane)
incineration was performed.2 An emission sample was collected during the 8.3 percent (by volume) CFC-12
1

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feed conccnirauon test to screen for polychlorinaied dibenzo-p-dioxins (PCDDs), polychlorinated dibenzolurans
(PCDFs), and polyaromatic hydrocarbons (PAHs). The PCDD/PCDF screening revealed that relatively high
concentrations of PCDD/PCDF (23.8 ng/m3 total PCDD/PCDF) were present in the incineration emissions.
These results were somewhat surprising, as the probability of gas-phase PCDD/PCDF formation is likely to be
very low at high temperatures.3 Heterogeneous PCDD/PCDF formation was considered unlikely because both
fuel and CFC were introduced as gases and no particulate was observed during this test.' More representative
CFC incineration emissions data were needed to substantiate or refute this finding.
The primary objectives of this AEERL-sponsored study were to characterize organic emissions resulting from the
incineration of CFCs under operating conditions typical of commercial incineration facilities as well as confirm
or refute the presence of PCDD/PCDF emissions at concentrations similar to those observed during the previous
AEERL-sponsored CFC incineration study.2 Particular emphasis was placed on PIC characterization Should
similar high PCDD/PCDF emission concentrations be observed, the screening of incinerator emissions for
volatile and semivolatile organic PICs may provide insight into potential PCDD/PCDF formation precursors or
intermediates.
Through an agreement with the EPA, T-Thermal Inc. made available one of their Conshohocken, PA, pilot-scale
test facilities to evaluate the incineration of CFC-11 and CFC-12. Under this agreement, T-Thermal Inc.
provided the equipment and labor resources necessary to prepare and operate the facility for the CFC incineration
tests. Acurex Environmental directed these tests, including coordination of sampling and analytical efforts.
EXPERIMENTAL
The incineration tests were performed at T-Thermal Inc.'s Conshohocken, PA, test facility. The test materials
(CFC-11 and CFC-12) were incinerated at several feed concentrations. A total of four tests were performed.
Table I presents the target CFC feed concentrations for each test. A combustion blank (no CFC incineration)
was included as a test condition.
TABLE I. TARGET CFC FEED CONCENTRATIONS
Test Condition
1 No. 2 fuel only
2 3 % (by mass) CFC-12/balance No. 2 fuel oil
3 3 % (by mass) CFC-ll/balance No. 2 fuel oil
4 50 % (by mass) CFC-ll/balance No. 2 fuel oil
Emissions samples were collected for volatile and semivolatile organics and subsequently analyzed to determine
DREs and screen for PICs. Emissions were sampled downstream of all pollution control devices. Scrubber
water samples were also collected to screen for semivolatile organic PICs. Because of limited access to the test
facility, each test was limited to approximately 2 hours in duration. This allowed two test conditions to be
evaluated daily.
The T-Thermal pilot-scale test facility is a down-fired, turbulent-flame incinerator nominally rated at 290 kW (1
MMBtu/h). A diagram of the test facility is presented in Figure 1. The incinerator consists of a T-Thermal LV-
1.3 high intensity vortex burner mounted tangentially near the top of the vertical, refractory-lined incineration
chamber. The No. 2 fuel oil and the CFC waste stream were introduced through the side-mounted burner, while
cooling water was introduced through the axially mounted top injector. The cooling water was injected into the
flame region to maintain a consistent incineration temperature of 1,093 °C (2,000 °F).
A thermal externally atomized tip (TEAT) injector was used to atomize the fuel oil/CFC waste stream. The
injector consists of three concentric pipes: the outer pipe providing atomizing air, an inner tube supplying fuel
oil, and the innermost pipe feeding the CFC waste stream. The fuel oil and CFC waste were mixed at the
injector tip. Combustion air was introduced to the system through the LV-1.3 windbox. In the incineration
chamber, the atomized fuel and waste stream combined with the combustion air through the induced vortex
action to sustain combustion and destroy the waste stream. The nominal residence lime was 1.5 seconds.
2

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Sampling,
Locations
Water
abiL
Venturi
Vortex
Burner
Gas Flow
Direction
Sub-X
Quench
Tank
Packed Tower Scrubber
Water Separators
Figure 1. T-Thermal incineration facility.
Hot gases leaving the incinerator passed through a quench tank which contains a water-washed down comer and a
pH-controlled water bath. The quench tank also served to transfer the heat from the hot gases exiting the
incineration chamber to the water bath. An alkaline solution (potassium hydroxide) was added to the quench
tank to neutralize acid gases. The water-saturated gases exited the quench tank at approximately 88 °C (190 *F)
and entered a venturi scrubber for paniculate and further acid gas removal. A pH-controlled packed-tower
scnibber neutralized any remaining acid gases.
Volatile and semivolatile organic incineration emissions were collected using conventional sampling
methodologies. Volatile organics were collected in Tedlar® bags as described in EPA Method 18. Semivolatile
organics, including PCDDs and PCDFs, were collected using EPA Method 23.5 All samples were collected
downstream of the pollution control equipment Duplicate samples were collected simultaneously for each test
condition. Scrubber liquor samples from each of the three system reservoirs were collected to screen for
semivolatile organic PICs as well.
Volatile organics, including CFCs, were analyzed by gas chroma to graphy/mass spectrometry (GC/MS).4,6 The
Method 23 samples were analyzed for semivolatile organics, including PCDDs and PCDFs, by high resolution
gas chromatography (HRGC) coupled with low resolution mass spectrometry (LRMS).7,8 The analytical
procedure used differs from the stated method in that individual PCDD/PCDF isomers were not identified. The
sampling train components (filter, XAD-2, and rinses) were extracted and analyzed as a single sample. All
Method 23 samples were analyzed for PCDDs and PCDFs. Only half of the Method 23 samples were screened
for other semivolatile organic PICs. The analytes targeted were limited to those considered to be potential
PCDD/PCDF precursors. These target analytes included chlorobenzenes (CBs), chlorophenols (CPs), and PAHs.
Instrument detection levels were also determined for these analytes.9
3

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The scrubber water samples were extracted as described in EPA Method 8280.7 Separate samples were extracted
for PCDD/PCDF and semivolatile organic PIC analyses.
RESULTS .AND DISCUSSION
Incinerator operational data arc summarized in Table II. The data presented are based on the average
measurements taken over each test period. The CFC feed concentrations are presented as a percentage of the
sum of fuel and waste mass flows. The CFC feed concentrations obtained were in accordance with those
established in the original test matrix. However, the high CFC feed concentration was significantly greater than
the targeted level (68.9 percent as opposed to 50 percent). The 50 percent feed concentration was targeted to
represent the maximum feed concentration likely to be employed. Of the data available pertaining to fuil-scale
incineration facilities, the greatest CFC feed concentration identified was 23.6 percent.1
TABLE II. T-THERMAL INCINERATOR OPERATIONAL DATA

Test 1
Test 2
Test 3
Test 4
Primary Combustion Air Flow - kg/h (lb/h)
285.7 (629.3)
293.7 (647.0)
300.5 (661.8)
295.3 (650.5)
Secondary Combusuon Air Flow - kg/h (lb/h)
100.9 (222.3)
106.4 (234 3)
106 9 (235.5)
110.8 (244.0)
Purge Air Bow - kg/h (lb/h)
f.6 (19.0)
9.2 (20.3)
9.8 (21 5)
9.1 (20.0)
Cooling Water Flow - kg/h (lb/h)
NA
14.7 (32 4)
9.1 (20 1)
8.7 (19.2)
No. 2 Fuet Oil Flow - kg/h (lb/h)
16.2 (35.6)
19.1 (42.0)
18.5 (40.8)
18 8 (41.4)
CFC-12 Flow - kg/h (lb/h)
0.0
0.5 (1.0)
0.0
0.0
CFC-11 Row • kg/h Gb/h)
0.0
0.0
0.5 (1.2)
41.6 (91.7)
Tola! Fuel/CFC Flow - kg/h (lb/h)
16.2 (35.6)
19.5 (43.0)
19.1 (42.0)
60.4 (133.1)
% CFC of Total Flow
0.0
2.3
2.9
689
% Excess Air
25.1
6.2
12.0
-6 1
Firing Rate - kW (MMBlu/h)
198 (0.676)
234 (0.797)
227 (0.776)
246 (0.839)
Incinerator Temperature - °C (°F)
1,070 (1,958)
1,092 (1,998)
1,092 (1,998)
1,121 (2,049)
Oxygen (% dry)
159
8.9
9.0
7.3
Carbon Dioxide (% dry)
7.0
10.7
9 3
10.6
Carbon Monoxide (ppmv dry)
0
8
10
15
Nitrogen Oxides (ppmv dry)
65
43
149
50
NA = Not available
Five nines (99.999 percent) DRE was achieved for the CFC-12 low feed concentration (2.3 percent) and the
CFC-11 high feed concentration (68.9 percent) tests. Only three nines (99.9 percent) DRE was achieved for the
CFC-11 low feed concentration (2.9 percent) test. A reason for this low DRE is not apparent, particularly
because good DRE was observed for the low CFC-12 feed concentration test condition. It is generally
recognized, however, that high DREs are easier to achieve at higher feed concentrations An analytical error is
not suspected as the measured concentrations of the separately collected duplicate samples agreed well.
However, a sampling contaminant is plausible. Similar concentrations of CFC-11 were measured in the CFC-12
incineration test samples Lesser concentratioas of CFC-11 were also present in the No. 2 oil baseline test
samples. Trace quantities of CFC-11 were also present in the nitrogen blanks.
The addition of water to the combustion chamber to control burner temperature may also enhance the thermal
destruction of CFCs. The addition of water would result in an increase in hydroxyl (OH) radicals. The OH
radicals provide a bimolecular destruction mechanism in addition to unimolecular bond rupture decomposition.10
In a turbulent flame reactor, Pedersen and Kallman have demonstrated that larger amounts of CFCs can be
thermally destroyed with the addition of steam."
4

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The volatile organic PICs screen results arc presented in Table III. The "less than" concentrations presented are
based on analyte practical quantitation limits (PQLs). Very few PICs were present in the baseline, low CFC-I2
feed concentration, and low CFC-11 feed concentration test conditions. Many of the PICs present were at or
near PQLs. The CFC-11 high feed concentration test condition did reveal a number of PICs in substantial
concentrations Chloroform was present at a relatively high concentration (1,500-1,600 pg/m3). Carbon
tetrachloride was also emitted but at a much lower concentration (170 Mg/m3) It has been shown that PICs
resulting from the thermal decomposition of chlorinated organic compounds favor the formation of unsaturated
1 2
chlorine and single carbon chlorine compounds.
TABLE III. VOLATILE ORGANIC PIC DATA SUMMARY
Test Condition !
Test 1
Test 2
Test 3 1
Test 4

No. 2 Fuel Oil Blank
CFC-12 Low Feed
CFC-11 Low Feed
CFC-11 High Feed
Concentration
Mg/m3
Hg'm
3
Mg/m3
Mg/m3
Sample
(a)
(b)
(a) 1
(b)
1
(a)
(b)
(a)
(b)
Compound








Didilorodifluoromethane
< 10
< 10
< 10
< 10
< 10
< 10 l
< 10
< 10
Chloromethane
< 10
< 10
220
< 10
< 10
< to
< 10
< 10
Vinyl chloride
< 10
< 10
< 10
< 10
< 10
< 10
< 10
< 10
Bromomethane
< 10
< 10
< 10
< 10
< 10
< 10
< 10
< 10
Chloroe thane
< 10
< 10
< 10
< 10
< 10
< 10
< 10
< 10
Tnchlorofluoromethane
34
87
270
130
270
290
490
320
1,1-Dichloroethene
< 10
< 10
< 10
< 10
< 10
< 10
< 10
< 10
Acetone
52
66
270
110
1300
55
160
410
Methylene chloride
< 10
< 10
18
110
47
< 10
15
23
Trans-1,2-dichloroethene
< to
< 10
< 10
< 10
< 10
< 10
< 10
< 10
1,1-Dichloroethane
< to
< 10
< 10
< 10
< 10
< 10
< 10
< 10
Chloroform
< 10
< 10
23
89
< 10
< 10
1500
1600
1,1,1 -Trichloroethane
33
< 10
13
< 10
28
< 10
< 10
17
Carbon tetrachloride
< to
< 10
< 10
< 10
< 10
< 10
170
170
1,2-Dichloroethane
< 10
< to
< 10
< 10
< 10
< 10
< 10
< 10
Benzene
< to
< to
< 10
< 10
< 10
< 10
< 10
< 10
Trichloroethene
80
It
< 10
< 10
< 10
< 10
< 10
< 10
1,2-Dichloropropane
< to
< to
< 10
< 10
< 10
< 10
< 10
< 10
Bromodichloromethane
< 10
< to
24
93
< 10
< 10
2000
1300
cis-1,3-Dichloropropene
< to
< 10
< 10
< 10
< 10
< 10
< 10
< 10
Toluene
72
31
350
87
280
1400
150
170
trans-1,3- Dichloropropene
< to
< to
< 10
< 10
< 10
< 10
< to
< 10
1,1,2-Trichloroe thane
25
< 10
< 10
< 10
< 10
< 10
< 10
< 10
T etrachloroethene
< 10
< to
< 10
< 10
< 10
< 10
-------
The PCDD/PCDF emissions data are summari7ed in Table IV. PCDDs and/or PCDFs were detected in all
samples collected. However, the mass of PCDD/PCDF material present in most of the test samples was at or
near levels present in field blanks. The data are sufficient to provide a quantitative comparison with the
PCDD/PCDF emissions data obtained during the initial AEERL-sponsored bench-scale study.2 This study
included a test in which PCDD/PCDF samples were collected while CFC-12 was incinerated at a feed
concentration of 8.3 percent (by volume) Total PCDD/PCDF emissions were measured to be 23.80 ng/m\ a
factor of 100 greater than highest concentration observed for the tests reported here.
TABLE IV. PCDD/PCDF EMISSIONS DATA SUMMARY
Test Condition
Test 1-No 2 Fuel Oil Baseline
Test 2-CFC-12 Low Feed Concentration
Sample
(a)
(b)
(a)
(b)
Cogener
No.
Isomers
Cone
(ng/m3)
No.
Isomers
Cone
(ng/m3)
No
Isomers
Cone
(ng/m3)
No.
Isomers
| Cone
i (ng/m3)
TCDDs
0
ND
2
13.574
1
0.317
0
ND
TCDFs
0
ND
0
ND
0
ND
0
ND
PeCDDs
0
ND
1
1.232
0
ND
0
ND
PeCDFs
0
ND
0
ND
0
ND
0
ND
HxCDDs
0
ND
2
7.220
0
ND
0
ND
HxCDFs
1
0.352
0
ND
0
ND
1
2.489
HpCDDs
2
2.099
0
ND
2
2.134
0
ND
HpCDFs
1
1.614
0
ND
I
0.901
0
ND
OCDD
1
2.018
0
ND
I
2.485
0
ND
OCDF
0
ND
0
ND
0
ND
0
ND
Tool

6.083

22.026

5.837

2.489
, Test J-CFC-11 Low Feed Concentration
Test 4-CFC-I1 High Feed Concentration
TCDDs
0
ND
7
45.629
2
18.034
0
ND
TCDFs
0
ND
9
44.896
4
77.014
3
96.009
PeCDDs
0
ND
2
2.633
4
11.907
0
ND
PeCDFs
0
ND
0
ND
9
23.251
0
ND
HxCDDs
0
ND
0
ND
1
1.861
0
ND
HxCDFs
0
ND
2
4.913
5
7.700
1
0.822
HpCDDs
0
ND
0
ND
1
0.431
0
ND
HpCDFs
0
ND
0
ND
0
ND
0
ND
OCDD
1
2.183
1
1.706
0
ND
1
2341
OCDF
0
ND
0
ND
0
ND
0
ND
Total

2.183

99.777

140.198

99.172
ND - Not Delected
6
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It is difficult to determine if PCDD/PCDF concentration is a function of CFC feed concentration. Figure 2
graphically depicts total PCDD/PCDF emissions for each test. It appears that the high CFC-11 feed
concentration condition resulted in slightly increased average PCDD/PCDF emissions. There is also better
agreement between the duplicate samples collected for this test condition. Because of the large variation in
results of the duplicate samples, it is difficult to characterize the CFC-11 low feed concentration test condition.
A sampling contaminant is suspected, as similar variation was observed in the Geld blanks. An analytical
contaminant is not suspected because PCDDs/PCDFs were not detected in the laboratory blanks.
No. 2 Fuel Oil CFC-12Low CPC-11 Low CFC-11 High
Train A RftSflTrain R E22 Average
Figure 2. Total PCDD/PCDF emissions for each test condition.
The scrubber water samples were also screened for PCDDs and PCDFs. The scrubber water was targeted for
screening because PCDDs and PCDFs possess relatively low vapor pressures and the scrubber water temperature
was only about 88 ®C (190 °F). Possibly, an equilibrium of condensed PCDDs/PCDFs could be reached in a
concentration great enough to be measured by the available screening procedure. This was a relatively important
consideration, because the initial AEERL-sponsored study sampled at a location upstream of any pollution
control equipment.2 Sampling upstream of the pollution control equipment was not considered for these tests
because of the high acid gas concentration of the incinerator emissions.
Unfortunately, these data also proved to be inconclusive. No PCDDs/PCDFs were detected in the scrubber water
before incineration testing, after Test 1, and after Test 3. However, substantial quantities of PCDDs/PCDFs
(195.0 ng/L total PCDD/PCDF) were present after Test 2, and to a lesser level (34.8 ng/L total PCDD/PCDF),
after Test 4. These results are confounding because no PCDDs/PCDFs were measured after Test 3 but were
7
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measured after Test 2. A definitive explanation is not obvious. The most logical source for this disparity is a
sampling or analytical contaminant However, no contaminant source was isolated.
Semivolatile organic PrCs screen results are presented in Table V. Target analytes focused on those compounds
considered to be PCDD/PCDF precursors. Only half of the Method 23 samples were analyzed The majority of
the target analytes were not detected. Based on instrumentation detection levels, "less than" emission
concentration levels are presented Bromoform was also tentatively identified in the high CFC-11 feed
concentration test condition sample. This serves to further confirm the presence of brorrunated PICs in
incinerator emissions No semivolatile organic target analytes were detected in the scrubber water samples.
TABLE V. SEMIVOLATILE ORGANIC PIC DATA SUMMARY

No. 2 Fuel Oil
CFC-12
CFC-11
CFC-11

Baseline
Low Feed
Low Feed
High Feed
Target Analytc

Concentration (jig/m3)

1,3- Dichlorobcnzcne
< 2.5
<2.3
< 2.4
< 3.2
1,4-Dichlorobenzene
< 2.8
< 2.5
<2.7
< 3.6
1,2-Dichlorobenzene
< 5.0
< 4.5
< 4.8
< 6.5
1,2,4-Trichlorobenzene
< 3.3
<2.9
< 3.1
< 4 .2
l,2,4,5-Tetrachlotobeti7£ne
< 4 6
< 4 1
< 4.3
< 5 9
2-Qilorophenol
< 9.0
< 8.1
< 8 6
< 11.6
2,6- Dichlorophenol
<4.2
<3.7
< 3.9
< 5.3
2,3,4-Tnchlorophenol
< 1.4
< 1.3
< 1.4
< 1.8
Pentachlorophenol
< 12.6
< 11.3
< 11.9
< 16.1
1 -Qiloronaphthalene
<2.4
<2.1
<2.2
<3.0
2-Oiloronaphthalene
< 1.6
< 15
< 1.5
< 2.1
Dibenzofuran
< 1.2
< 1.1
< 1.2
< 1.6
Naphthalene
< 1.9
< 1.7
< 1.8
<2.5
Acenaphthylene
<0.4
<04
< 0 4
<06
Aceoaphthene
< 1.5
< 1.3
<1.4
< 1.9
Fluorene
< 1.9
< 1.7
< 1.8
<2.5
Fluoranthene
29.7
< 12
< 1.3
< 1.7
Phenanthrene
< 0.8
< 0.7
<0.8
< 1.0
Anthracene
37.1
< 1.2
< 1.3
< 1.7
Chrysene
<2.4
< 21
<2.2
<3.0
B enzo(a)anlhraceae
<0.9
<0.8
<0.8
< 1.1
BeQZo(k)fluorantheoe
< 13.8
< 12.4
< 13.0
< 17.7
Benzo(»)p>Teoe
< 10.1
<9.1
<9.5
< 129
Indeno(l ,2,3-c,d)pyreae
< 16 3
< 14.7
< 15.4
< 20.9
Dibenz(a,h)anthracene
< 1X5
< 11.2
< 11.8
< 16.0
Benao(g,h.i)perytene
<23.7
<21.3
< 22.4
< 30.4
Pyreoe
41.5
<3.3
<3.5
<4.7
The absence of chlorobenzenes and PAHs and low PCDD/PCDF concentrations may be attributable to the water
injection. During the incineration of CFC-12, Pedersen and KSllman determined that the single important
chemical factor in reducing the formation of chlorobenzenes and PAHs was the halogen/hydrogen ratio." The
increase in available hydrogen resulting from water injection may be sufficient to decrease the ratio to levels
where the formation of chlorobenzenes and PAHs is negligible, and since those compounds are suspected
precursors for PCDDs and PCDFs, the increase in available hydrogen may have inhibited PCDD/PCDF
formation.
CONCLUSIONS AND RECOMMENDATIONS
This study effectively characterized the organic emissions resulting from the pilot-scale incineration of CFCs.
CFC-12 and CFC-11 were destroyed/removed at feed concentrations representative of full-scale thermal
destruction facilities (2.3 and 2.9 percent, respectively). A high CFC-11 feed concentration condition (68.9
percent) was also evaluated. Greater than 5 nines DRE was observed for the CFC-12 and high CFC-11 test
conditions Only three nines DRE was observed for the low CFC-11 feed concentration test condition.
8
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The presence of volatile and semivolatile organic PICs was screened for. The PIC screens included target
analytes such as chlorinated aliphatics, CBs, CPs, PAHs, and PCDDs/PCDFs. Essentially, no target PICs were
found for the low CFC feed concentration tests. The high CFC-11 feed concentration test condition PIC screens
did indicate that several volatile organic target PICs, as well as several non-target volatile organic PICs, were
indeed formed. Chloroform, bromodichloromethane, dibromochloromethane, and bromoform were emitted in
substantial concentrations (1,500-2,300 jjg/m3). Carbon tetrachloride was also generated, but at a lower
concentration (170 pg/m ). The presence of brominated PICs was particularly surprising, as no source of
bromine was readily identifiable; the CFC-11 and fuel oil used during testing were analyzed specifically for trace
bromine and found to be free of bromine. Prior tests on the incineration test facility were suspected as the
bromine source.
Essentially no semivolatile organic PIC target analytes were detected. This finding is significant in that CBs and
PAHs, PICs identified in a bench-scale CFC incineration study, were not detected.
The total PCDD/PCDF emission concentrations measured (2-140 ng/m3) were a factor of 100 less than those
reported in another AEERL-sponsored CFC incineration study,2 indicating that the formation of PCDDs/PCDFs
from the incineration of CFCs may not be as large a concern as was initially suspected. It does appear,
however, that increased PCDD/PCDF emissions were realized at the high CFC-11 feed concentration test
condition.
The injection of water into the combustion zone to control incinerator temperature may have several benefits.
The injection of water may enhance CFC destruction efficiency. Water injection would lead to an increase in the
hydroxyl radical population, thereby providing a bimolecular destruction mechanism in addition to unimolecular
thermal bond rupture. The injection of water may also reduce the formation of PICs. The injected water also
provides an additional source of hydrogen. Hydrogen is involved in reactions that scavenge halogen free
radicals. As a result, the addition of water may also have contributed to the low emissions of PCDDs and
PCDFs.
Whereas this study was effective in evaluating CFC incineration viability, the study also revealed several
additional interesting topics. Specifically, the effect of water or steam addition to the combustion zone as well as
the incineration of waste CFCs are not fully understood.
The addition of water to the combustion zone may have a positive effect on both CFC destruction efficiency and
PIC minimization. However, it is certainly possible that a large number of incineration facilities do not add
water or steam to the combustion zone. It would be interesting to evaluate a high CFC feed concentration
without the addition of water or steam.
This study only marginally evaluated the incineration products of two CFCs. Many other CFCs ultimately
requiring disposal exist The CFCs evaluated during these tests were unused, reagent grade products. Waste and
recycled CFCs were not examined. Characterizations of combustion products of waste/recycled refrigeration
CFCs should be helpful. These products are likely to have had long-term contact with copper tubing. The
possibility exists that some copper may have been leached from tubing, particularly if any acids were present.
The catalytic properties of copper in PCDD/PCDF formation are well characterized13,14.
ACKNOWLEDGEMENTS
This study was conducted under EPA contract 68-DO-0141 with Acurex Environmental Corporation. C. W. Lee
was the EPA Task Officer. The valuable contributions made by T-Thermal Inc. are also acknowledged.
DISCLAIMER
The contents of this paper should not be construed to represent EPA policy nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.
9
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REFERENCES
1.	Dickerman, J.C., Emmel, T.E., Harris, G E. and Hummel, K.E., "Technologies for CFC/Halon
Destruction," EPA-600/7-89-011 (NTIS PB90-116955), U.S. Environmental Protection Agency-Air and
Energy Engineering Research Laboratory, Research Triangle Park, NC, October 1989.
2.	Hassel, G.R., "Experimental Investigation of PIC Formation in CFC Incineration," EPA-600/7-91-010
(NTIS PB92-126952), U.S. Environmental Protection Agency-Air and Energy Engineering Research
Laboratory, Research Triangle Park, NC, December 1991.
3.	Shaub, W.M. and Tsang, W„ "Dioxin Formation in Incinerators," Environmental Science and
Technology, 17:721-730, 1983.
4.	Method 18, "Measurement of Gaseous Organic Compounds Emissions by Gas Chromatography," in
Title 40 Code of Federal Regulations Part 60, Appendix A, U.S. Government Printing Office,
Washington, DC, 1991.
5.	Method 23, "The Analysis of Polychlorinated Dibenzo-p-dioxins and Polychlorinated Dibenzofurans
from Stationary Sources," in Title 40 Code of Federal Regulations Part 60, Appendix A, U.S.
Government Printing Office, Washington, DC, 1991.
6.	Method 8240, "Gas Chromatography/Mass Spectrometry for Volatile Organics," in Test Methods for
Evaluating Solid Waste, Volume IB: Laboratory Manual Physical/Chemical Methods, EPA-SW-846
(NTIS PB-88-239223), 3rd ed., U.S. Environmental Protection Agency, Washington, DC, 1986.
7.	Method 8280, "The Analysis of Polychlorinated Dibenzo-p-dioxins and Polychlorinated Dibenzofurans,"
in Test Methods for Evaluating Solid Waste, Volume IB: Laboratory Manual Physical/Chemical
Methods, EPA-SW-846 (NTIS PB-88-239223), 3rd ed., U.S. Environmental Protection Agency,
Washington, DC, 1986.
8.	Method 8270, "Gas Chromatography/Mass Spectrometry for Semivolatile Organics: Capillary Column
Technique," in Test Methods for Evaluating Solid Waste, Volume IB: Laboratory Manual
Physical/Chemical Methods, EPA-SW-846 (NTIS PB-88-239223), 3rd ed., U.S. Environmental
Protection Agency, Washington, DC, 1986.
9.	Appendix B to Part 136, "Definition and Procedure for the Determination of the Method Detection
Limit-Revision 1.11," in Title 40 Code of Federal Regulations Part 136, Appendix B, U.S. Government
Printing Office, Washington, DC, 1991.
10.	Graham, J.L., Hall, D.L. and Dellinger, B„ "Laboratory Investigation of Thermal Degradation of a
Mixture of Hazardous Organic Compounds," Environmental Science and Technology, 20:703-710, 1986.
11.	Pedersen, J.R. and Kallman, B„ "Investigation of the Thermal Destruction of Chlorofluoromethanes in a
Turbulent Flame," Chemosphere, 24(2): 117-126, 1992.
12.	Tsang, W„ "Mechanisms for the Formation and Destruction of Chlorinated Organic Products of
Incomplete Combustion," Combustion Science and Technology, 74:99-116, 1990.
13.	Stieglitz, L„ Zwick, G„ Beck, J. and Vogg, H„ "On the de-novo Synthesis of PCDD/PCDF on Fly Ash
of Municipal Waste Incinerators," Chemosphere, 18:1219-1226, 1989.
14.	Gullett, B., Bruce, K. and Beach, L., "The Effect of Metal Catalysts on the Formation of
Polychlorinated Dibenzo-p-dioxin and Polychlorinated Dibenzofuran Precursors," Chemosphere,
20:1945-1952, 1990.
10
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.rc,DT „ irtno TECHNICAL REPORT DATA
A Hj bK Lj~ r~ 1U (0 (Please read Inslructions on the reverse before cotnple
1. REPORT NO. 2.
EPA/600/A-94/008
3.
4. TITLE AND SUBTITLE
Organic emissions from Pilot-scale Incineration of
CFCs
5. REPORT DATE
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(SI J. V. Ryan (Acurex), c> w. Lee (EPA/AEERL),
and Steven Korn (T-Thermal)*
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING OROANIZATION NAME AND ADDRESS
Acurex Environmental Corporation
P.O. Box 13109
Research Triangle Park, North Carolina 27709
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-DO-0141, Tasks 92-081
and 93-149
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Air and Energy Engineering Research Laboratory-
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Published paper; 1/92-4/93
14. SPONSORING AGENCY CODE
EPA/600/13
is. supplementary NOTES AEERL project officer is C.W.Lee, Mail Drop 65. 919/541-7663.
Presented at 12th Annual Incineration Conference, Knoxville, TN, 5/3-7/93.
(*) T-Thermal, Inc., Brook. Rd. , Conshohocken, PA 19028.
16. abstract paper gives results of the characterization of organic emissions result-
ing from the pilot-scale incineration of trichlorofluoromethane (CFC-ll) and dichloro-
difluoromethane (CFC-12) under varied feed concentrations. (NOTE: As a result of
the Montreal Protocol, an international accord implemented to reduce the production
and use of stratospheric ozone depleting substances, considerable quantities of chlor-
ofluorocarbons (CFCs) and halons may be accumulated and ultimately require dispos-
al or destruction. Incineration is a potential destruction technology; however, little is
known of the combustion emission characteritics from CFC incineration.) A 293~kW
(1 million Btu/h) incinerator was made available to the EPA for the characterization,
which focused on determining the destruction efficiencies (DEs) and major Droducts
of incomplete combustion (PICs) for each CFC evaluated. Sampling was performed to
screen for volatile and semivolatile organic emission products including chlorinated
aliphatics, chlorobenzenes, chlorophenols, polychlorinated dibenzodioxins and furans
(PCDDs and PCDFs), and polyaromatic hydrocarbons (PAHs). Results indicate that
99.999% DE can be achieved at a CFC-ll feed concentration as high as 69% by mass.
The formation of volatile and semivolatile organic PICs was minimal. "Less than"
concentrations are presented for target analytes not detected.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATl Field/Group
Follution
Halohydrocarbons
Incinerators
Organic Compounds
Emission
Ozone
Pollution Control
Stationary Sources
Chlorofluorocarbons
Thermal Destruction
Destruction Efficiency
13 B
07 C
14G
07B
13. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report)
Unclassified
21 . NO. OF PAGES
20. SECUR1 rY CLASS (This page}
Unclassified
'Z2. PRICE
EPA Form 2220-1 (9-73)
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