United States
Environmental Protection
Agency
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/SR-93/047 May 1993
vxEPA Project Summary
Pilot-Scale Incineration of
Contaminated Soils from the
Drake Chemical Superfund Site
C. King, J.W. Lee, and LR. Waterland
A series of pilot-scale incineration
tests was performed at the U.S. Envi-
ronmental Protection Agency's (EPA's)
Incineration Research Facility (IRF) to
evaluate the potential of incineration
as an option to treat contaminated soils
from the Drake Chemical Superfund site
in Lock Haven, PA. The soils at the
Drake site are reported to be contami-
nated to varying degrees with various
organic constituents and several haz-
ardous constituent trace metals. The
purpose of the test program was to
evaluate the incinerability of selected
site soils in terms of the destruction of
contaminant organic constituents and
the fate of contaminant trace metals.
All tests were conducted in the rotary
kiln incineration system (RKS) at the
IRF.
Test results show that destruction
and removal efficiencies (ORE) of
greater than 99.995% can be achieved
for the principal organic hazardous con-
stituents (POHC) at kiln exit gas tem-
peratures of nominally 816 C (1,500°F)
and 538 C (1,000 F). Complete soil de-
contamination of semivolatile organics
was achieved; however, kiln ash levels
of three volatile organic constituents
remained comparable to soil levels.
Kiln ash accounted for the predomi-
nant fraction of all contaminant trace
metals with the exception of mercury,
which appeared to be entirely in the
flue gas discharge. The flue gas dis-
charge from the venturi/packed-column
scrubber air pollution control system
(APCS) accounted for a minor fraction
of all contaminant trace metals, with
the exception of mercury, cadmium,
and, possibly, arsenic. The scrubber
liquor accounted for less than 10% of
the contaminant metals, with the ex-
ception of copper and chromium, and,
in one case, nickel. Kiln temperature in
the range tested, as above, did not af-
fect overall metal distributions in incin-
erator discharges.
None of the soils tested, nor the kiln
ash resulting from their incineration,
would be considered a toxicity charac-
teristic (TC) hazardous waste because
of their teachable trace metal contents.
Further, no test scrubber liquor would
be considered a TC hazardous waste
because of trace metal concentrations.
Lead concentrations in test scrubber
liquors were, however, at levels near
50% of the toxicity characteristic leach-
ing procedure (TCLP) regulatory level
in some cases. This suggests that the
scrubber liquor discharge from a wet
scrubber APCS could become a TC haz-
ardous waste in the incineration of "hot
spot" lead-containing soils or under
scrubber operation at minimum
blowdown. The flyash collected at the
afterburner exit (upstream of the wet
scrubber APCS) would be a TC hazard-
ous waste because of leachable chro-
mium and lead concentrations and, in
one case, arsenic and cadmium con-
centrations. This suggests that the col-
lected particulate from a dry ACPS
(such as a fabric filter) would be a TC
hazardous waste.
This Project Summary was developed
by EPA's Risk Reduction Engineering
Laboratory, Cincinnati, OH, to announce
Printed on Recycled Paper
-------
key findings of the research project
that is fully documented in a separate
report of the same title (see Project
Report ordering information at back).
Introduction
One of the primary missions of the
EPA's IRF is to support regional offices in
evaluations of the potential of incineration
as a treatment option for contaminated
soils and sediments at Superfund sites.
One priority Superfund site is the Drake
Chemical site, in Lock Haven, PA. EPA
Region 3 requested that test burns be con-
ducted at the IRF to support evaluations
of the suitability of incineration as a treat-
ment technology for the contaminated soils
and sediments at the site.
The Drake Chemical site, covering ap-
proximately 12.5 acres, was a chemical
manufacturing facility from 1951 to 1982.
According to site investigation data, as a
result of these activities, the soils at the
Drake site are contaminated to varying
degrees with various organic constituents
and several hazardous constituent met-
als. With respect to incinerability evalua-
tion, the primary objective was to deter-
mine whether treatment of the soils by
incineration would generate a residue en-
vironmentally suitable for redeposit, with-
out further treatment, at the site during
full-scale remediation. Therefore, one pri-
mary concern was whether incineration
could effectively destroy the organic con-
taminants in the soils. Equally important
was what the fate of the trace metals in
the soils would be when the soils were
subjected to incineration.
This test program was designed to
evaluate the effectiveness of varying in-
cinerator operating conditions on organic
contaminant destruction and the effects of
these varied conditions on the distribu-
tions of the trace metals in the discharge
streams. Specific questions answered in
this test program were
• Can rotary kiln incineration effectively
destroy the organic contaminants in
the site soils?
• Will incineration-treated site soils have
characteristics that will allow it to be
backfilled (redeposited), without further
treatment, at the site?
• Can site soils be incinerated in
compliance with the hazardous waste
incinerator performance standards?
• What is the fate of the contaminant
trace metals in the incineration of the
site soils?
• What are the effects of incineration
temperature on contaminant metal fate
and kiln ash characteristics?
This test program, as originally con-
ceived, was to have consisted of an initial
phase of nine tests and an optional phase
of four additional tests. The results from
the initial-phase testing, specifically the
toxicity characteristics exhibited by the in-
cinerator residuals, were to guide the de-
cision as to whether the optional testing
would be needed. A subset of the initial-
phase incineration testing was conducted
at the IRF in January and February 1991.
The TCs of all test program samples were
below regulatory threshold levels. These
results led to the conclusion that several
of the originally conceived initial-phase
tests and the optional testing would not
be necessary to meet the stated program
objectives.
Results of the test program are dis-
cussed in the subsections that follow.
Test Program
Test Facility
A process schematic of the RKS is
shown in Figure 1. The IRF RKS consists
of a primary combustion chamber, a tran-
sition section, and a fired afterburner cham-
ber. After exiting the afterburner, flue gas
flows through a quench section followed
by a primary APCS. The primary APCS
for these tests consisted of a venturi scrub-
ber followed by a packed-column scrub-
ber. Downstream of the primary APCS, a
backup secondary APCS, composed of a
demister, an activated-carbon adsorber,
and a high-efficiency particulate (HEPA)
filter, is in place.
Test Waste Description
The Phase III record of decision (ROD)
document for the Drake Chemical site in-
dicates that about 252,000 yd3 of contami-
nated soils and sediments will be exca-
vated and decontaminated onsite by a
transportable rotary kiln incinerator. The
ROD further indicates that these materials
are contaminated with varying levels of
organic compounds and several hazard-
ous constituent trace metals, including ar-
senic, barium, cadmium, chromium, lead,
and mercury.
For the test program, seventeen 55-gal
drums of the contaminated site soils were
excavated and shipped to the IRF for pos-
sible testing. Only a subset of these drums
was actually used in the test program,
however.
Test Conditions
As noted above, the objective of the
proposed test program was to evaluate
the suitability of incineration as a treat-
ment technology for the contaminated soils
and sediments at the Drake Chemical site.
The rescoped test program consisted of
five tests. The test numbering of the origi-
nally conceived test program was retained,
however. Of the five conditions tested,
three (Tests 1, 2, 3a, and 3b) were de-
signed to study the fate of the inorganic
contaminants (trace metals). Tests 1 and
2 studied the distribution of the trace metal
contaminants throughout the incinerator
system. These tests also provided infor-
mation on the concentrations of trace met-
als in the kiln ash and flue gas flyash
TCLP leachates. Tests 3a and 3b deter-
mined the effects of kiln temperature on
the trace metal concentrations in the kiln
ash and scrubber liquor streams. All of
these tests were conducted with the soils
in their original, as-received form. Tests 6
and 7 were designed to study the destruc-
tion of the organic contaminants. Because
the as-received soils contained low levels
of organic contamination, the Test 6 and
Test 7 soils were spiked with naphthalene
and 1,4-dichlorobenzene at 3,000 and
130mg/kg, respectively. The destruction
of the spiked POHCs became the princi-
pal indicator of the effectiveness of incin-
eration under these test conditions.
The five tests were conducted from
January 30, 1991, through February 7,
1991. Tests 3a and 3b were performed in
one day, with sufficient time allowed in
between subtests to achieve steady-state
operation at the target kiln temperature of
816°C (1,500°F) for Test 3a and 538°C
(1,000°F) for Test 3b. Test soils were fed
to the kiln via the fiberpack drum ram
feeder system. Each fiberpack contained
4.5kg (10lb) of soil. One fiberpack was
charged into the kiln every 5 min, result-
ing in soil feedrates of nominally 55 kg/hr
(120lb/hr).
Table 1 compares the target and actual
test operating conditions for each test. As
shown, the average kiln temperatures were
within about 15°C (25°F) of the target
temperatures for all of the tests. After-
burner temperatures were maintained
within 3°C (5°F) of the 1,093°C (2,000°F)
target for all tests. O2 levels in the flue gas
exiting both the kiln and afterburner were
somewhat higher than target levels for all
tests, however, because the rotating kiln
seals could not be tightly secured and
excessive air leaked into the kiln. Never-
theless, based on the IRF's past experi-
ence, the results would not have been
different had the flue gas O2 levels been
on target.
Table 2 summarizes the total amount of
soil fed to the RKS for each test and the
corresponding weight of ash collected for
each test. As shown, except for Test 7,
the weight of ash discharged was gener-
ally about 70% of the weight of soil fed to
the kiln.
-------
Quench
Natural
Gas,
Liquid
Feed
Transfer Duct
S/ng/e -Stage Ionizing
Wef Scrubber
Rofary
KHn
Natural Gas,
Liquid Feed
Scrubber Liquor
Recirculation
Atmosphere
Carbon Bed HEPA
Adsorber Filter
Stack
ID Fan
floteryK//n
Incinerator
Modular Primary Air
Pollution Control
Devices
Redundant Air
Pollution Control
System
Figure 1. Schematic of the IRF rotary kiln incineration system.
Sampling and Analysis
Procedures
Because the objectives of Tests 1, 2,
3a, and 3b were different from those of
Tests 6 and 7, different sampling and
analysis procedures were employed for
each test group. Several procedures were,
however, performed for all tests:
• obtaining a composite sample for the
soil feed from each drum before the
soil was packaged into fiberpack
containers,
• collecting a composite kiln ash
sample,
• collecting a composite scrubber liquor
sample,
• continuously measuring O2 concen-
trations at the kiln exit; O2, CO, CO2,
and total unburned hydrocarbon
(TUHC) at the afterburner exit; O2,
CO , and NO at the scrubber exit;
and CO and flJHC at the stack, and
• sampling the flue gas at the stack for
HCI and particulate, by using a
Method 51 sampling train.
The above were the only sampling
procedures employed for Tests 3a and
3b. In addition to the above, the
following were performed for Tests 1
and 2:
• sampling the flue gas at the
afterburner exit (i.e., upstream of the
scrubber) for particulate load and for
trace metals (excluding mercury), by
using a Method 171 sampling train,
modified with multiple metals train
impingers,
• determining the particle size
distribution of the afterburner exit flue
gas particulate, by using an Anderson
cascade impactor train,
• sampling the flue gas upstream and
downstream of the scrubber for
mercury, by using a Method 101 A2
train at each location, and
• sampling the flue gas downstream of
the scrubber system for particulate
and trace metals (excluding mercury),
by using the EPA multiple metals
train.3
In addition to the sampling performed
for all tests noted above, the flue gas
downstream of the scrubber system was
sampled for semivolatile POHCs, by using
a Method 00104 sampling train, in Tests 6
and 7.
In addition to analyzing flue gas sam-
pling trains for their sampled analyte set,
the following were performed for Tests 1,
2, 3a, and 3b.
• analyzing the soil feed and kiln ash
samples for trace metals (arsenic,
MO CFR 60, Appendix A
!40 CFR 61, Appendix B
340 CFR 266, Appendix IX
"SW-846
-------
Table 1. Target Versus Actual Operating Conditions for the Drake Chemical Soil Tests
Kiln
Afterburner
Test
no.
1
2
3a
3b
6
7
Target
temperature,
°C(°F)
816 (1,500)
816(1,500)
816 (1,500)
538 (1,000)
816(1,500)
538 (1,000)
Actual average
temperature, 1
°CfF)
826(1,519)
823 (1,513)
829 (1,524)
546(1,015)
822 (1,512)
553 (1,027)
'arget C
%
11.0
11.0
11.0
11.0
11.0
11.0
Actual
average
Target 02
Actual
average
13.3
13.1
13.8
17.0
12.7
15.4
7.0
7.0
7.0
7.0
7.0
7.0
8.7
9.2
9.2
11.8
9.3
9.9
Table 2. Soil Feed and Ash Collected
1
2
3a
3b
6
7
Test
(1/30/91)
(2/5/91)
(1/31/91)
(1/31/91)
(2/6/91)
(2/7/91)
barium, cadmium, chromium, copper,
mercury, nickel, lead, selenium, silver,
and zinc),
• analyzing the soil and kiln ash TCLP
leachates for trace metals, and
• analyzing the scrubber liquor samples
for trace metals.
In addition, for Tests 1 and 2, an aliquot
of the afterburner exit particulate collected
with the Method 17 sampling train was
extracted by the TCLP and the resulting
leachate analyzed for trace metals. For
Tests 6 and 7, the analysis protocol in-
cluded analyzing the soil feed, kiln ash,
and scrubber liquor samples for volatile
and semivolatile organic contaminants.
Test Results
Inorganic-Contaminated-Soil
Tests
Table 3 provides a complete summary
of the trace metal analysis results for all
test samples taken for trace metal analy-
sis. The data in Table 3 show that soil
feed and resulting kiln ash metal concen-
trations were generally comparable for all
metals. The concentrations of metals in
the afterburner exit particulate were, how-
ever, significantly greater than correspond-
ing soil feed and kiln ash concentrations
for all metals in the two tests for which
afterburner exit particulate was collected
Total ash collected
Test soil
M-2
M-5D
O-1
O-1
L-2
O-2
Total soil
fed, kg (Ib)
240 (529)
232 (512)
1 12 (246)
1 13 (249)
240 (529)
209 (460)
Weight,
kg (Ib)
173(381)
177(390)
74 (163)
83 (183)
187(411)
183 (404)
Fraction of
soil fed, %
72
76
66
73
78
88
for analysis. Flue gas particulate at the
afterburner exit was analyzed as an ana-
log to the flyash collected by dry APCSs.
The data in Table 3 suggest that the fly-
ash collected by a fabric filter APCS, for
example, will likely contain significantly
higher levels of all test program trace met-
als (except mercury) than does the parent
soil incinerated.
Tests 1, 2, and 3a were performed at a
kiln temperature of nominally 824°C
(1,515°C). TestSb was performed at a
lower kiln temperature of 546°C (1,015°F)
to evaluate whether variations in kiln tem-
perature in this range affected resulting
kiln ash trace metal contents. The data in
Table 3 show no significant differences in
the trace metal contents of the kiln ash
from Test 3a compared to Test 3b.
The data in Table 3 show that kiln ash
TCLP leachates were quite similar in metal
content to the corresponding soil
leachates, with the exception that the
Test 2 leachate had a significantly lower
zinc concentration than its corresponding
soil. Still, no soil or kiln ash resulting from
its incineration in these tests had TCLP
leachate trace metal concentrations even
approaching the TCLP regulatory levels.
Thus, the kiln ashes resulting from the
incineration of site soils would not be TC
hazardous wastes based on these test
data.
In contrast, the concentrations of met-
als in leachates of the afterburner exit flue
gas particulate were significantly higher
than corresponding soil and resulting kiln
ash leachate concentrations. In fact, the
particulate leachate concentrations of chro-
mium and lead exceeded their correspond-
ing TCLP regulatory levels for both Tests 1
and 2; and the Test 2 particulate leachate
was at or over the regulatory levels for
arsenic and cadmium. Because the after-
burner exit flue gas particulate was col-
lected as an analog for dry APCS (e.g.,
fabric filter) collected flyash, the data in
Table 3 suggest that the collected flyash
from the incineration of soil highly con-
taminated by trace metals would be a TC
hazardous waste, not suitable for land dis-
posal without further treatment.
The scrubber liquor trace metal data
show that no scrubber liquor contained
trace metal concentrations exceeding
TCLP regulatory levels. In two of three
cases, however, lead concentrations in
test scrubber liquor were nearly 50% of
the regulatory level for lead. This sug-
gests that the scrubber liquor discharge
from a wet APCS, generated in the incin-
eration of "hot spot" lead-containing soils
or under scrubber operation at minimum
blowdown, could be a TC hazardous
waste.
The test sample concentration data from
Table 3 can be combined with waste
feedrate and kiln ash discharge rates and
flue gas flowrate data to calculate the
distribution of trace metals among the vari-
ous incinerator discharges of the tests.
Table 4 summarizes these trace metal dis-
tributions among the incinerator discharge
streams, expressed as fractions (in per-
cent) of the amount of each metal fed to
the incinerator in each test. Thus, the val-
ues in the table represent the fraction of
the metal fed to the kiln accounted for by
the noted discharge. The rows labeled
"Total" represent the total amount of metal
fed accounted for by the sum of the dis-
charges analyzed. Thus, these rows rep-
resent the degree of mass balance clo-
sure achieved for each metal for each
test.
The data in Table 4 show that the kiln
ash fraction contained the predominant
amount of all metals, except mercury, for
both Tests 1 and 2. Scrubber exit flue gas
fractions were generally quite low for all
metals except for mercury, cadmium, and
possibly arsenic for both tests. The flue
gas accounted for all measured mercury
for both tests. The scrubber liquor ac-
counted for less than about 10% of the
amount of metal fed for all metals except
-------
16
<0.1
13
<0.1
<0.1
3.2-13.8
mg/kg 50
TCLP <3
167
0.44
211
<0.01
1.4
105
590
11
1.1
<0.01
1.1
<0.01
<0.01
2.2
9.5
0.4
18
<0.03
22
<0.03
0.57
54
168
5.8
49
<0.01
41
<0.01
1.7
7.6
117
3.4
439
<0.06
403
<0.06
2.7
74
570
12
0.1
<0.002
<0.1
<0.002
<0.002
3.9-4.2
NAa
NA
17
<0.03
22
<0.03
0.47
59
178
4.9
<10
<0. 1
<10
<0. 1
<0. 1
<2.7
<25
<3
<2
<0.02
<2
<0.02
<0.02
0.9-3. 1
15
<0.5
302
0.05
234
<0.02
1.2
78
684
15
1.4-4.2 2.3-6.3 7.7-16.8 8.3-11.1 132-150 9.2-9.3 <9.1 3.0-7.0 2.7-8.9
Table 3. Test Sample Trace Metal Concentrations
Sample As Ba Cd Cr Cu Pb
Test 1 (1/30/91)
Soil feed (M-2), mg/kg
Soil feed TCLP leachate, mg/L
Kiln ash, mg/kg
Kiln ash TCLP leachate, mg/L
Scrubber liquor, mg/L
Afterburner exit flue gas,/\ig/dscm
Afterburner exit flue gas particulate,
Afterburner exit flue gas particulate
leachate, mg/L
Scrubber exit flue gas,\ig/dscm 6.2-46
Test 2 (2/5/91)
Soil feed (M-5D), mg/kg 62 57 2.0 12 43
Soil feed TCLP leachate, mg/L <0.1 <0.01 0.015 <0.03 <0.01
Kiln ash, mg/kg 16 48 1.7 9.8 21
Kiln ash TCLP leachate, mg/L 0.14 <0.01 <0.01 <0.03 <0.01
Scrubber liquor, mg/L 0.66 0.74 0.021 0.18 1.3
Afterburner exit flue gas^ig/dscm 108 57 5.2 94 18
Afterburner exit flue gas particulate, mg/kg 462 223 20 209 160
Afterburner exit flue gas particulate TCLP 31 9.6 1.0 11 7.2
leachate, mg/L
Scrubber exit flue gas,\ig/dscm
Test 3 (a and b) (1/31/91)
Soil feed (O-1), mg/kg 11 194 <1.0 20 35
Soil feed TCLP leachate, mg/L <0.1 <0.01 <0.01 <0.03 <0.01
Scrubber liquor, mg/L <0.1 1.1 0.015 0.24 1.4
Test 3a (829PC [1,524°F])
Kiln ash, mg/kg <10 199 1.4 24 39
Kiln ash TCLP leachate,mg/L <0.1 <0.01 <0.01 <0.03 <0.01
Test3b(546°C[1,015°F])
Kiln ash, mg/kg <10 184 <1.0 18 42
Kiln ash TCLP leachate, mg/L <0.1 <0.01 <0.01 <0.03 <0.01
TCLP regulatory level, mg/L 5.0 100 10 5.0 -b
Hg
Ni
Se
Zn
15
43-84 2.4-5.5 6.5-10.6 3.7-12.9 14-17
77
<0.06
38
<0.06
1.3
88
554
20
74-93
443
0.06
2.3
345
<0.06
410
<0.06
5.0
0.3
<0.002
<0,1
<0.002
<0.002
5.7-5.9
NA
NA
15
0.2
<0.002
<0.002
<0.1
<0.002
<0.1
<0.02
0.2
15
<0.03
8.7
<0.03
0.13
76
110
5.9
<9.2
12
<0.03
0.17
23
0.032
18
<0.03
—
<10 <2
<0. 1 <0.02
<10 &
<0. 1 <0,02
<0.1 <0.02
<1.6 <1.9
<10 <2
<3 <0.5
<7.3 4.7-11.4
<10 <2
<0.1 <0.02
<0. 1 <0.02
<10 <2
<0. 1 <0.02
<10 <2
<0. 1 <0.02
1.0 5.0
251
1.5
115
<0.02
1.2
158
777
28
36
272
0.07
1.3
192
0.35
299
<0.02
—
*NA = Not analyzed
°- = Not a TCLP metal
chromium, copper, and nickel in Test 1,
and copper in Test 2.
The metal distribution data for Tests 3a
and 3b generally support the observations
from Tests 1 and 2 discussed above. The
kiln ash discharge again accounted for
the predominant fraction of each metal
except mercury, which was not found in
the kiln ash of either Test 3a or 3b. Again,
the scrubber liquor accounted for less than
about 10% of the amount of metal fed for
all metals except copper. Comparing the
kiln ash fraction data of Test 3a and Test
3b shows that decreasing the kiln tem-
perature from 829°C (1,524°F) to 546°C
(1,015°F) had no effect on kiln ash metal
fractions, with the possible exception of
increased kiln ash zinc with decreased
temperature.
Scrubber collection efficiencies for each
of the metals measured in the flue gas
streams for Tests 1 and 2 can be calcu-
lated from measured concentrations in the
afterburner exit flue gas and the scrubber
exit flue gas. The IRF's experience, how-
ever, has been that flue gas metal con-
centrations measured at this location are
generally lower than expected. Thus, cal-
culated scrubber collection efficiencies us-
ing measured metal concentrations in af-
terburner exit flue gas are often quite poor.
Based on past experience, a better esti-
mate of the flowrate of metals at the scrub-
ber inlet has been obtained by summing
the flows in the two scrubber discharge
streams: the scrubber exit flue gas and
the scrubber liquor. This allows an appar-
ent scrubber collection efficiency to be
calculated as (scrubber liquor fraction)/
(scrubber liquor fraction plus scrubber exit
flue gas fraction).
Table 5 summarizes the apparent scrub-
ber collection efficiencies calculated for
each metal measured in the test program
for Tests 1 and 2. The data in Table 5
show that the collection efficiencies of the
venturi/packed-column scrubber system
were greater than about 90% for barium,
chromium, copper, nickel, and zinc in
Test 1, and possibly chromium and nickel
in Test 2. Cadmium collection efficiencies
were less than 30% to 40%, and mercury
collection efficiencies less than 5% for both
tests. Lead collection efficiencies were
nominally 80% for both tests. Arsenic col-
lection efficiencies were between 64% and
78% for Test 2 but less than 36% for
Test 1.
Organic-Contaminated-Soil
Tests
Table 6 summarizes the results of the
organic analyses of the organic-contami-
nated test soils. As shown in the table,
fenac was present in the L-2 test soil at
70 mg/kg. Fenac was not detected in the
O-2 test soil. The results in Table 6 also
indicate that both test soils contained low
levels of several volatile organics and that
the O-2 soil contained low levels of sev-
eral semivolatile organics.
Because the organic test soils contained
very low levels of organic contamination,
they were spiked with naphthalene and
1,4-dichlorobenzene to the 3,000 mg/kg
and 130 mg/kg levels, respectively. These
two semivolatile compounds became sur-
rogate test POHCs. Measured naphtha-
-------
Table 4. Trace Metal Distributions
Distribution, % of metal fed
Sample
Testl (1/30/91), SoilM-2
Kiln temperature: 826° C (1,519°F)
Kiln ash
Afterburner exit flue gas
Total
Kiln ash
Scrubber exit flue gas
Scrubber liquor
Total
Test 2 (2/5/91), Soil M-5D
Kiln temperature: 823° C (1,513°F)
Kiln ash
Afterburner exit flue gas
Total
Kiln ash
Scrubber exit flue gas
Scrubber liquor
Total
As
56
0.7-3
57-59
56
2-11
<6
58-73
20
6
26
20
3-5
9
32-34
Ba
90
2
92
90
<0.1
8
98
65
4
69
65
0.2-0.4
11
76
Cd
71
7
78
71
8-22
<9
79-102
65
9
74
65
12-20
9
86-94
Cr
88
11
99
88
2-4
32
122-124
61
28
89
61
1-4
13
75-78
Cu
61
0.6
62
61
1
34
96
37
2
39
37
1
26
64
Pb
66
0.6
67
66
1
6
73
38
4
42
38
4-5
14
56-57
Hg
<71
150-160
150-231
<71
350
<20
350-441
<2.5
68-71
68-96
<25
195-198
<6
195-229
Ni
91
12
103
91
<2
27
118-120
45
19
64
45
<2
g
53-55
Test 3a (1/31/91), Soil O-1
Kiln temperature: 829°C (1,524°F)
Kiln ash (a)
Test3b (1/31/91), Soil O-1
Kiln temperature: 546° C (1,015°F)
Kiln ash (a)
69
(b)
(b)
83
69
75
88
52
68
<35
129
108
Zn
55
0.9
56
55
0.2
4
59
35
2
37
35
0.6
4
40
48
81
Total Test 3
Kiln ash
Scrubber liquor
(a)
(a)
70
3
(b)
(b)
76
7
82
22
61
3
<35
<6
118
8
65
3
bCadmium not detected in Test 3 soil.
lene ORE was greater than 99.995% for
both tests. No 1,4-dichlorobenzene was
detected in the scrubber exit flue gas,
with a ORE corresponding to the quantita-
tion limit for 1,4-dichlorobenzene of greater
than 99.89%. The spiking level for 1,4-
dichlorobenzene, mistakenly chosen to be
130mg/kg, combined with the flue gas
sampling and analysis method PQL, was
too low to allow establishing a higher ORE.
The lower kiln temperature for Test 7,
553°C (1,027°F), when compared with the
Test 6 kiln temperature of 822°C (1,512°F),
did not result in a measurable decrease in
ORE.
Neither fenac nor any other semivolatile
organic was detected in any other organic-
contaminated soil test sample.
The volatile organic constituent analy-
sis results for kiln ash and scrubber liquor
are summarized in Table 7. As shown in
the table, both tests' (Tests 6 and 7) scrub-
ber liquor contained toluene. The Test 7
scrubber liquor also contained 2-butanone.
Both tests' kiln ash contained 2-butanone
and toluene. In addition, the Test 7 kiln
ash contained xylenes. Comparing the kiln
ash 2-butanone, toluene, and xylene con-
centrations with the corresponding feed
concentrations noted in Table 6 shows that
they are comparable in all cases. Evi-
dently, incineration at both kiln tempera-
tures was ineffective in decontaminating
the test soils of these three volatile organ-
ics. The authors can offer no explanation
for this observation.
Paniculate and HCI Emissions
Data
Flue gas particulate load measurements
were made at various sampled locations
for different tests. Particulate levels in the
afterburner exit flue gas were in the nomi-
nal range of 100 to 300 mg/dscm at 7%
02 for Tests 1, 2, 6, and 7. Scrubber exit
particulate levels were reduced to the
nominal range of 10 to 20 mg/dscm at 7%
0 for the two tests (Tests 1 and 2) during
which this location was sampled. The re-
duction corresponds to a scrubber effi-
ciency in the 90% to 95% range, typical
for a venturi scrubber. Both scrubber exit
levels measured were below the 180 mg/
dscm at 7% O2 hazardous waste incinera-
tor performance standard.
Flue gas HCI levels were also mea-
sured at the afterburner exit and in the
stack during the test program. Afterburner
exit flue gas HCI was 13 ppm for Tests
(L-2 soil) and 201 ppm for Test 7 (O-2
soil). All levels were below detection limits
at the stack for all tests. Corresponding
system HCI collection efficiencies were
greater than 98.5% for Test 6, and greater
than 99.8% for Test 7.
Conclusions
Test conclusions are as follows:
• Organic contaminants in the test soils
can be destroyed to greater than
99.99% ORE. Naphthalene, spiked
into test soils at 3,000 mg/kg for the
two organic destruction tests, was
destroyed at a ORE of greater than
99.995%. 1,4-Dichlorobenzene
-------
Table 5. Apparent Scrubber Collection Efficien-
cies
Apparent scrubber
collection efficiency, %
Table 6. Organic Analysis Results for Feed
Samples
Concentration, mg/kg
Metal
Arsenic
Barium
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Zinc
Testl
(1/30/91)
<36
98.8-99.6
<29
90-95
98
82-84
<5
>93
94
Test 2
(2/5/91)
64-78
97-99
31-43
76-91
94-95
76-79
<3
>76
88
spiked into the test soils at 130 mg/
kg for the same two tests, was not
detected in incineration flue gas;
detection limits corresponded to a
ORE of greater than 99.89%. These
ORE levels were attained at both kiln
temperatures tested, 822°C (1,512°F)
and 553°C (1,027°F), although the
afterburner was operated at 1,096°C
(2,005°F) for both tests. No native
soil semivolatile POHCs were
detected in combustion flue gas.
The treated soil (kiln ash) contained
no detectable semivolatile organic
soil contaminant; this indicated
effective decontamination for this
class of contaminants at both kiln
temperatures. The levels of three
volatile organic soil contaminants, 2-
butanone, toluene, and xylene, in kiln
ash were, however, comparable to
parent soil concentrations at both
kiln temperatures; this suggested
poor decontamination effectiveness
for these constituents.
None of the soils tested, nor the kiln
ash resulting from their incineration,
would be considered a TC hazardous
waste because of their leachable trace
metal content.
No test scrubber liquor would be
considered a TC hazardous waste
because of trace metal concentrations.
Lead concentrations in test scrubber
liquors were, however, at levels near
50% of the TCLP regulatory level in
some cases. This suggests that the
scrubber liquor discharge from a wet
scrubber ARCS could become a TC
hazardous waste in the incineration
of "hot spot" lead-containing soils or
under scrubber operation at minimum
blowdown.
The flyash collected at the
afterburner exit (upstream of the wet
scrubber ARCS) would be a TC
Compound
Test 6 Test 7
(2/6/91) (2/7/91)
SoilL-2 SoilO-2
Semivolatile organics:
Benzo(a)pyrene
Fluoranthene
lndeno(l,2,3-cd)pyrene
Phenanthrene
Pyrene
1,2,4- Trichlorobenzene
ND'
ND
ND
ND
ND
ND
All other semivolatile organics ND
Volatile organics:
2-Butanone
Chlorobenzene
Trichloroethene
Toluene
Xylenes (total)
Fenac
11
44
24
58
43
43
ND
20
5.7
<0.63
0.69
<0.63
rganics ND
70
20
2.9
4.5
4.7
3.0
ND
<10
aND = Not detected.
hazardous waste because of
leachable chromium and lead
concentrations in both metal-
contaminated soils tested in the full
evaluation tests and, additionally,
because of leachable arsenic and
cadmium in one soil. This suggests
that the collected particulate from a
dry ARCS, such as a fabric filter,
would be a TC hazardous waste and
could not be backfilled at the site
without further treatment or
stabilization.
Particulate levels in the flue gas at
the exit of the venturi/packed-column
scrubber ARCS were less than 20 mg/
dscm (0.1 grains/dscf) at 7% O2, in
compliance with the hazardous waste
incinerator performance standard of
180 mg/dscm (0.08 grains/dscf) at 7%
O2. HCI emissions were not detectable
downstream of the scrubber. Thus,
the hazardous waste incinerator
performance standard for these
constituents can be met.
• The kiln ash discharge accounted for
the predominant fraction of all trace
metals introduced in the soil feed with
the exception of mercury, which
appeared to be completely accounted
for in the flue gas discharges. The
scrubber exit flue gas accounted for
a minor fraction of the trace metals
fed with the exception of mercury,
cadmium, and possibly arsenic. The
scrubber liquor accounted for less
than 10% of the trace metals fed with
the exception of copper and of
chromium and nickel for one soil feed.
• Kiln ash trace metal concentrations
were generally comparable to the
corresponding soil feed con-
centrations. Afterburner exit flue gas
particulate metal concentrations,
however, were significantly greater.
• Varying kiln temperature in the range
of 546°C (1,015°F) to 829°C (1,524°F)
generally had no effect on
contaminant metal fate or kiln ash
characteristics
• Venturi/packed-column scrubber
collection efficiencies were 90% to
95% for overall particulate. Apparent
collection efficiencies were greater
than about 90% for barium, chromium,
copper, nickel, and zinc; about 80%
for lead; less than 30% to 40% for
cadmium; and variable, between 36%
and 78%, for arsenic.
The full report was submitted in fulfill-
ment of Contract No. 68-C9-0038 by
Acurex Environmental Corporation under
the sponsorship of the U.S. Environmen-
tal Protection Agency.
Table 7. Volatile Organic Constituent Concentrations in Kiln Ash and Scrubber Liquor Samples
Test:
Date:
Feed:
Kiln temperature, °C:
Volatile organics:
2-butanone
Toluene
Xylenes (total)
Kiln ash
concentration, mg/kg
6
2/6/91
Soil L-2
•: 822
26
0.84
<0.62
7
2/7/91
Soil O-2
553
16
8.4
0.86
Scrubber liquor
concentration, \ig/L
6
2/6/91
Soil L-2
822
<100
5
<50
7
2/7/91
Soil O-2
553
190
6
<50
•U.S. Government Printing Office: 1993— 750-071/60235
-------
C. King, J. W. Lee, and LR. Waterland are with Acurex Environmental Corpora-
tion, Jeferson, AR 72079.
R.C. Thurnau is the EPA Project Officer (see below).
RE, Mournighan was the EPA Technical Project Monitor.
The complete report, entitled "Pilot-Scale Incineration of Contaminated Soils
from the Drake Chemical Superfund Site," (Order No. PB93-163004; Cost:
$36.50, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
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POSTAGE & FEES PAID
EPA
PERMIT No. G-35
EPA/600/SR-93/047
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