United States
Environmental Protection
Agency
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/SR-93//036 April 1993
1&EPA Project Summary
Pilot-Scale Incineration of
Contaminated Soil from the
Chemical Insecticide Corporation
Superfund Site
A. Siag, D.J. Fournier, Jr., and L.R. Waterland
A detailed test program was per-
formed at the U.S. Environmental Pro-
tection Agency's (EPA's) Incineration
Research Facility (IRF) to define the
Incineration characteristics of contami-
nated soil from the Chemical Insecti-
cide Corporation (CIC) Superfund site
in Edison Township, NJ. The soils at
the site are highly contaminated with
organochlorine pesticides and trace
metals. The major metal contaminant,
arsenic, Is present in site soils at lev-
els up to 8,000 mg/kg. The purpose of
these tests was to evaluate the inciner-
ability of these soils in terms of the
destruction and removal efficiency
(ORE) for organochlorine pesticides
(chlordane and p,p'-DDT), the fate of
arsenic in terms of the system removal
efficiency (RE), and the fate of other
contaminant trace metals. Four incin-
eration tests were completed in the IRF
rotary kiln incineration system (RKS),
which was equipped with a high-effi-
ciency scrubber system, a Calvert Flux
Force/Condensation scrubber*. In three
of the four tests, soil alone was fed to
the kiln of the RKS. In the fourth test,
lime was blended with the soil to evalu-
ate whether arsenic RE was affected.
All tests were performed at a kiln exit
gas temperature of approximately 982°C
(1,800°F) and an afterburner exit gas
temperature of 1,204°C (2,200°F). The
Calvert scrubber was operated at a
pressure drop of approximately 12 kPa
(50 in. WC).
* Mention of trade names or commercial products does
not constitute endorsement or recommendation for
use.
Incineration under the conditions
tested resulted in the elimination of the
soil pesticide contaminants. No pesti-
cide contaminants were present in the
scrubber exit flue gas with correspond-
ing DREs of at least 99.9916% for p,p'-
DDT. Arsenic REs of 99.99% can be
achieved with the Calvert scrubber un-
der the conditions tested feeding soil
alone. Adding lime to the soil did not
measurably improve arsenic RE. Trace
metal concentrations in the toxicity
characteristic leaching procedure
(TCLP) leachates of both untreated soil
and kiln ash (treated soil) were signifi-
cantly below corresponding toxicity
characteristic (TC) regulatory levels for
all metals except arsenic. Soil leachate
arsenic concentrations were 40% to
50% of the regulatory level. Kiln ash
leachate arsenic concentrations were
near or above arsenic's TC regulatory
level. Adding lime to the soil signifi-
cantly reduced both the soil and the
resulting kiln ash TCLP leachate ar-
senic concentrations. Nominally 70%
of the arsenic measured in the incin-
erator discharges was in the kiln ash in
all of the tests in which soil alone was
fed; about 30% was in the scrubber
liquor. The kiln ash arsenic fraction in-
creased to about 90% in the test in
which lime was added to the soil; about
10% was in the scrubber liquor. Scrub-
ber exit flue gas accounted for a negli-
gible fraction of the arsenic discharged
in all tests. Paniculate levels at the
Calvert scrubber exit were nominally
10 to 20 mg/dscm at 7% O well below
the hazardous waste incinerator per-
Printed on Recycled Pape;
-------
formance standard of 180 mg/dscm at
7% O2. Calvert scrubber apparent HCI
collection efficiencies were 99.95% or
greater, which is above the hazardous
waste incinerator performance standard
of 99.9%.
Test results suggest that conven-
tional rotary kiln incineration in a unit
equipped with a high-efficiency scrub-
ber system such as the Calvert system
would be an appropriate treatment tech-
nology for site soils: elimination of the
contaminant organochlorine pesticides
and greater than 99.99-% organic con-
taminant DREs were achieved; arsenic
REs of greater than 99.96% were
achieved; and the hazardous waste in-
cinerator particulate and HCI perfor-
mance standards were easily achieved.
The treated soil may be a TC hazard-
ous waste for soils with arsenic con-
centrations in the range of those of the
soil tested. Adding lime to the soil be-
fore incineration, however, can signifi-
cantly reduce the teachability of the
kiln ash arsenic in the TCLP test.
This Project Summary was developed
by EPA's Risk Reduction Engineering
Laboratory, Cincinnati, OH, to announce
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 IRF
is to support EPA's Regional Offices in
evaluating the potential of incineration as
a treatment option for contaminated soils
at Superfund sites. CIC is a priority site in
Edison Township, NJ. EPA Region 2 re-
quested that test burns be conducted at
the IRF to support an evaluation of the
suitability of incineration as a treatment
technology for the contaminated soils at
the CIC site. Region 2 was specifically
interested in whether flue gas emissions
of arsenic could be limited to less than
0.04% of the amount of arsenic in the
highly arsenic-contaminated soil fed to the
incinerator.
The CIC site was formerly used to manu-
facture pesticide products. The results of
the remedial investigation and feasibility
study (RI/FS) show that the soils at the
site are highly contaminated by orga-
nochlorine pesticides and arsenic. Dioxin
(i.e., 2,3,7,8-tetrachlorodibenzo-p-dioxin)
has also been found at concentrations up
to 1.8ng/kg (ppb) in some soil samples
collected during the RI/FS. Thermal treat-
ment has previously been demonstrated
to be an effective means of destroying
pesticides, dioxin, and other organic com-
pounds. The finding of high concentra-
tions of arsenic in the soils at the CIC site
has raised the question of whether a ther-
mal treatment unit treating soil from the
site, and operating under conditions ca-
pable of attaining a 99.9999-% ORE for
dioxin and a 99.99-% ORE for other or-
ganic contaminants, can also reduce ar-
senic concentrations to acceptable levels
in the stack emissions. Therefore, this in-
cineration test program focused on the
ability of an incineration system to control
the arsenic emissions to levels acceptable
to the EPA, while operating at incineration
conditions sufficient to destroy dioxin and
other organic materials to the prescribed
ORE.
The test program was designed to de-
velop the data to support feasibility study
(FS) efforts in evaluating incineration as a
possible remedial alternative. The specific
objectives of the test program were
• To confirm the ability of conventional
rotary kiln incineration to destroy
organochlorine pesticide contaminants
in the soil, as measured by their
absence in the treated soil (kiln ash)
discharge
• To confirm the ability of a conventional
rotary kiln incinerator, with a high-
efficiency scrubber, to achieve an
arsenic RE of 99.96% under operating
conditions associated with a
99.9999% dioxin ORE, where RE is
defined as
= 100 (1-
flue gas emission rate
feedrate
A series of four incineration tests was
performed using the IRF's RKS with the
Calvert Flux Force/Condensation scrub-
ber for air pollution control. In three of the
tests, raw soil alone was packaged into
1.5-gal fiberpacks and fed to the RKS kiln
via the system's ram feeder. In the fourth
test, raw soil was mixed with lime at a
blend ratio of 0.5 kg of lime per 10 kg of
soil before being packaged.
Test Program
Test Facility
All tests were performed in the IRF RKS.
A process schematic of the RKS is pro-
vided in Figure 1. The RKS consists of a
rotary kiln primary combustor followed by
an afterburner chamber. Downstream of
the afterburner, the combustion gas is
quenched and then the gas flows through
a primary air pollution control system
(APCS). A high-efficiency wet scrubber
system consisting of the Calvert Flux
Force/Condensation scrubber pilot plant
was used for these tests. Downstream of
the primary APCS, a secondary backup
APCS consisting of a carbon bed absorber
and a high-efficiency particulate air (HEPA)
filter is in place.
The Calvert scrubber system consisted
of a condenser/absorber section, a Calvert
Collision scrubber, two entrainment sepa-
rators, a wet electrostatic preciprtator (de-
signed to provide the final stage of par-
ticulate removal), a caustic injection sys-
tem, and an induced-draft (ID) fan (Fig-
ure 2). The IRF RKS quench chamber and
heat exchanger systems were used in-
stead of the quench chamber and cooling
tower usually installed with the Calvert
pilot unit. The Calvert scrubber liquor was
recirculated through the facility heat ex-
changer for scrubber liquor cooling. The
key operating parameter of the scrubber
system, pressure drop, was maintained at
12 kPa (50 in. WC), as recommended by
Calvert Environmental, the scrubber's ven-
dor. Pressure drop was controlled by a
variable-speed drive on the ID fan.
Test Soil Description
The CIC site was formerly used to manu-
facture a variety of pesticides for commer-
cial and military applications, including a
wide range of insecticides, fungicides, ro-
denticides, and herbicides. One specific
product, 2,4,5-trichlorophenoxyacetic acid
(2,4,5-T), might have contained dioxin as
a byproduct. Pesticide manufacturing ac-
tivities, with associated process-water stor-
age lagoons, and poor housekeeping led
to the widespread chemical contamination
of this site.
The RI/FS showed that site soils were
contaminated with the pesticides p,p'-DDT,
p,p'-DDD, p.p'-DDE, a-BHC, y-BHC, and
chlordane; the herbicides 2,4-D, 2,4,5-T,
and Silvex; and the trace metals arsenic,
cadmium, chromium, lead, and mercury.
Arsenic levels as high as 8,000 mg/kg were
found. Dioxin was found in some site soil
samples at a maximum concentration of
1.8 |ig/kg.
Four drums of soil were excavated from
the CIC site in February 1991 for this test
program. Composite characterization
samples were taken for pretest analysis.
The results showed that soil with an ar-
senic content of about 900 mg/kg was
available for testing. This same soil was
also contaminated with an average of
2 mg/kg of p,p'-DDD; 3 mg/kg of p,p'-
DDE; 26 mg/kg of p,p'-DDT; and 9 mg/kg
of chlordane.
Before testing, the test soil was pack-
aged into 1.5-gal plastic-bag-lined fiber-
pack containers for feeding to the RKS
via the ram feeder in place on the system.
Each fiberpack was filled with 4.5 kg (10 Ib)
-------
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7. Schematic of the IRF rotary kiln incineration system.
of soil, its plastic bag was secured with a
wire tie, and then the fiberpack's lid was
secured.
Test Conditions
The test series was designed specifi-
cally to determine whether incineration can
attain a 99.96% RE for arsenic under op-
erating parameters associated with a
99.9999-% dioxin ORE. The kiln chamber,
afterburner chamber, and ARCS operat-
ing parameters were held nominally con-
stant throughout the test program. The
target incinerator operating conditions for
each test are given in Table 1.
Sampling and Analysis
The scope of the sampling efforts un-
dertaken during this test program is illus-
trated and the sampling locations are iden-
tified in Figure 3. The sampling effort com-
pleted during each test consisted of:
• Obtaining a composite sample of the
soil feed from each drum before the
soil was packaged into the fiberpack
containers.
Table 1. Target Incinerator Test and Operating Conditions
Kiln exit gas temperature
Afterburner exit gas temperature
Kiln exit O2 level
Afterburner exit O2level
Kiln solids residence time
Total waste soil feedrate
Calvert scrubber pressure drop
Scrubber liquor temperature
Scrubber liquor blowdown rate
982°C (1,800°F)
1,204°C (2,200°F)
10%
7.9%
O.Shr
55kg(120lb)
12.4 kPa (50 in. WC)
66°C (150°F)
0 to 2 L/min (0 to 0.5 gpm)
-------
From IRF
Heat
Exchanger
IRF
Secondary
APCS
To IRF
Heat
Exchanger
To
Quench
Sump
To
Slowdown
Storage ^—'
Tank
Figure 2. Schematic of the Calvert scrubber system.
Wet
Electrostatic
Precipitator
• Collecting a composite sample of the
kiln ash.
• Collecting a composite sample of the
scrubber liquor.
• Continuously measuring O2 levels in
the kiln exit and afterburner exit flue
gases; O2, CO, CO2, and NOx levels
at the scrubber exit; and O2, CO, and
CO2 levels at the stack.
• Sampling flue gas at the scrubber
system exit for organochlorine
pesticides, arsenic, and particulate
and HCI.
• Sampling at the stack downstream of
the secondary ARCS for arsenic and
particulate and HCI.
Aliquots of the soil feed and kiln ash
sample for each test were subjected to
the TCLP. The soil feed, soil feed TCLP
leachate, kiln ash, and scrubber liquor
sample for each test was analyzed for
organochlorine pesticides and the trace
metals arsenic, barium, cadmium, chro-
mium, lead, mercury, selenium, and sil-
ver. The kiln ash TCLP leachate sample
for each test was analyzed for the above
trace metals. Flue gas sampling train
samples were analyzed for this sampled
analyte.
Table 2. Organochlorine Pesticide Analysis Results
Concentration
Sample
Chlordane a-BHC y-BHC p,p'-DDE p,p'-DDD p,p'-DDT
Test 1 (8/6/91)
Soil feed, mg/kg
Soil feed TCLP leachate, pg/L
Kiln ash, mg/kg
Scrubber liquor, \ig/L
Scrubber exit flue gas, \ng/dscm
14
<10
<0.10
<1.0
<0.33
<2.0
8.3
<0.02
<0.20
<0.066
<2.0
2.3
<0.02
<0.20
<0.066
5.5
<2.0
<0.02
<0.20
<0.066
7.3
<2.0
<0.02
<0.20
<0.066
65
<2.0
<0.02
<0.02
0.10
Test 2 (8/8/91 )
Soil feed, mg/kg 17 <2.0 <2.0 6.7 7.3 92
Soil feed TCLP leachate, iig/L <10 4.4 <2.0 <2.0 2.6 <20
Kiln ash, mg/kg <0. 10 <0.02 <0.02 <0.02 <0.02 <002
Scrubber liquor, pg/L <1.0 <0.20 <0.20 <0.20 <0.20 <0.20
Scrubber exit flue gas, \ig/dscm <0.30 <0.060 <0.060 <0.060 <0.060 <0.060
Test 3 (8/1 3/91)
Soil feed, mg/kg <10 <2.0 <2.0 3.4 4.3 41
Soil feed TCLP leachate, pg/L <10 3.6 <2.0 <2.0 <2.0 <20
Kiln ash, mg/kg <0. 10 <0.02 <0.02 <0.02 <0.02 <002
Scrubber liquor, \ig/L <1.0 <0.20 <0.20 <0.20 <0.20 <0 20
Scrubber exit flue gas, \ig/dscm <0.31 <0.061 <0.061 <0.061 <0.061 <0.061
Test 4 (8/1 5/91)
Soil feed, mg/kg 13 <2.0 <2.0 4.8 64 46
Soil feed TCLP leachate, \ig/L <10 <2.0 <2.0 <2.0 <2.0 <2.0
Kiln ash, mg/kg <0. 10 <0.02 <0.02 <0.02 <0.02 <002
Scrubber liquor, \ig/L <1.0 <0.20 <0.20 <0.20 <0.20 <0 20
Scrubber exit flue gas, \ig/dscm <0.31 <0.062 <0.062 <0.062 <0.062 0.077
TCLP regulatory level, \ig/L 30 _a 400
a_ = Has no TCLP regulatory level.
-------
Kiln
i — >
After-
Burner
— P .-•»•
Quench
Section
Calvert
Scrubber
Carbon
Bed
HEPA
Filter
>( ID
I Fan
^ — -»
Sampling
point Soil feed Kiln ash
1 X
2 X
3
4
5
6
7
Calvert
scrubber
liquor
X
Continuous
flue gas
monitoring
X
X
X
X
Method 0010
(organochlorine
pesticides)
X
Method 108
(arsenic)
X
X
Methods
(paniculate
andHCI)
X
X
Figure 3. Sampling matrix.
Test Results
Results from the test program performed
are discussed in the subsections that fol-
low. Test results are grouped by analyte
class.
Organochlorine Pesticides
Analysis Results
Table 2 summarizes the results of the
organochlorine pesticide analyses. The
data indicate that the soil feed contained
between <10 and 17 mg/kg of chlordane;
between 3.4 and 6.7 mg/kg of p,p'-DDE;
between 4.3 and 7.3 mg/kg of p,p'-DDD;
and between 41 and 92 mg/kg of p,p'-
DDT. None of these soil contaminants,
however, was found in any of the feed
TCLP leachate, kiln ash, or scrubber li-
quor samples. Low levels of p,p'-DDT were
found in the scrubber exit flue gas in two
of the four tests, although no other pesti-
cide analyte was found.
Table 3 summarizes the lower bound
degree of pesticide decontamination
achieved corresponding to the kiln ash
practical quantitation limits (PQLs) and
identifies the upper bound fraction of the
amount of each pesticide introduced in
the incinerator feed that could have been
present in the kiln ash discharge in each
test. The data show that no more than
0.62% of the chlordane, 0.44% of the p,p'-
DDE, 0.34% of the p.p'-DDD, or 0.04% of
the p,p'-DDT fed to the incinerator could
have been discharged in the kiln ash.
Thus, the decontamination effectiveness
of incineration under the conditions tested
was at least 99.38% for chlordane; 99.56%
Table 3. Organochlorine Pesticide Decontamination Effectiveness
Parameter
Chlordane
p,p'-DDE
p.p'-DDD
p,p'-DDT
Test 1 (8/6/91)
Soil feed
Concentration, mg/kg
Amount fed, g
Kiln ash
Concentration, mg/kg
Amount discharged, mg
Fraction of amount fed, %
Test 2 (8/8/91)
Soil feed
Concentration, mg/kg
Amount fed, g
Kiln ash
Concentration, mg/kg
Amount discharged, mg
Fraction of amount fed, %
Test 3 (8/13/91)
Soil feed
Concentration, mg/kg
Amount fed, g
Kiln ash
Concentration, mg/kg
Amount discharged, mg
Fraction of amount fed, %
Test 4 (8/1 '5/91)
Soil feed
Concentration, mg/kg
Amount fed, g
Kiln ash
Concentration, mg/kg
Amount discharged, mg
Fraction of amount fed, %
14
3.03
<0. 1
< 16
<0.54
17
3.73
<0. 1
< 17
<0.47
<10
<2.1
<0. 1
< 16
_a
13
2.78
<0. 1
< 17
<0.62
5.5
1.17
<0.02
<3.3
<0.28
6.7
1.45
<0.02
<3.5
<0.24
3.4
0.71
<0.02
<3.1
<0.44
4.8
1.07
<0.02
<3.4
<0.32
7.3
1.55
<0.02
<3.3
<0.21
7.3
1.59
<0.02
<3.5
<0.22
4.3
0.92
<0.02
<3.1
<0.34
6.4
1.42
<0.02
<3.4
<0.24
65
14.0
<0.02
<3.3
<0.02
92
19.9
<0.02
<3.5
<0.02
41
8.77
<0.02
<3.1
<0.04
46
10.1
<0.02
<3.4
<0.03
a_ = Not applicable because not detected in the feed.
-------
Table 4. Organochlorine Pesticide DREs
Parameter Chlordane
p,p'-DDE p.p'-DDD p,p'-DDT
Test 1 (8/6/91)
Pesticide feedrate, mg/hr 791
Scrubber exit flue gas emission <990
rate, \ig/hr
ORE, % >99.87
Test 2 (8/8/91)
Pesticide feedrate, mg/hr 951
Scrubber exit flue gas emission <860
rate, u.g/hr
ORE, %
Test 3 (8/13/91)
Pesticide feedrate, mg/hr
>99.910
<540
Scrubber exit flue gas emission <890
rate, \ig/hr
ORE, % a
Test 4 (8/15/91)
Pesticide feedrate, mg/hr
712
Scrubber exit flue gas emission <880
rate, \ig/hr
ORE, %
>99.88
305
<200
>99.934
371
<170
>99.954
183
<180
>99.901
275
<180
>99.935
405
<200
>99.951
405
<170
>99.958
234
<180
>99.923
366
<180
>99.951
3,640
306
99.9916
5,100
<170
>99.9967
2,240
<180
>99.9920
2,600
219
99.9916
a_ = Not applicable because not detected in the feed.
for p,p'-DDE; 99.66% for p.p'-DDD; and
99.96% for p.p'-DDT.
Table 4 summarizes the organochlorine
pesticide DREs achieved for the tests as
measured at the scrubber system exit.
For the two tests in which p.p'-DDT was
detected in the scrubber exit flue gas
(Tests 1 and 4), the ORE achieved was
99.9916%. This exceeds the 99.99-% prin-
cipal organic hazardous constituent
(POHC) ORE requirement in the hazard-
ous waste incinerator performance stan-
dard. The lower bound DREs achieved for
p.p'-DDT in Tests 2 and 3 based on the
flue gas emission stream PQL were also
greater than 99.99%. Lower bound DREs
based on the flue gas emission stream
measurement PQLs were greater than
99.87% for chlordane, 99.901% for p,p'-
DDE, and 99.923% for p.p'-DDD. The ex-
pectation is that all three of these com-
pounds were destroyed at greater than
99.99% ORE; however, method PQLs
were too high to unambiguously establish
this when these compounds were present
at the lower concentrations in the soil feed.
The data in Tables 3 and 4 also show that
adding lime to the test soil in Test 4 had
no effect on the effectiveness of incinera-
tion in decontaminating the soil or on the
DREs for the organochlorine pesticide
compounds.
Arsenic and Other Trace Metal
Distributions
Tables summarizes the arsenic con-
centrations measured and the resulting
feedrates and flue gas emission rates for
the four tests performed. The arsenic RE
achieved for Test 1 at the scrubber exit,
99.89%, was less than the target of
99.96%. This result was obtained on a
quick-turnaround laboratory analysis.
Based on this result, Test 4 was performed
with lime blended with the soil to evaluate
whether lime addition affected arsenic RE.
Table 5. Arsenic Removal Efficiencies
In contrast to the Test 1 experience, the
arsenic REs measured at the scrubber
exit in Tests 2 and 3 were 99.990% and
99.991%, respectively, greater than the
target 99.96%. The authors have no ex-
planation for the order of magnitude higher
scrubber exit arsenic emission rate expe-
rienced in Test 1 compared to Tests 2 and
3. The 99.991 -% scrubber exit arsenic RE
in Test 4, in which lime was added to the
soil, was comparable to the REs in Tests 2
and 3.
Table 6 summarizes the concentrations
of all eight of the test metals in the soil
feed and in each of the incinerator dis-
charge streams analyzed. The table also
notes the soil feed and kiln ash TCLP
leachate metal concentrations for each
test, and the TCLP regulatory levels for
each TCLP metal determined. Comparing
feed soil leachate, kiln ash leachate, and
scrubber liquor metals concentrations to
the TCLP regulatory levels shows that no
regulatory level was exceeded for any
metal except arsenic. No feed soil would
be an arsenic TC hazardous waste. How-
ever, the Test 1 kiln ash was a TC haz-
ardous waste for arsenic, and the Tests 2
and 3 kiln ash leachates contained ar-
senic levels near the regulatory limit. The
arsenic concentrations in TCLP leachates
of both the feed soil and the kiln ash for
Test 4 were reduced from the levels mea-
sured in the other three tests. This sug-
gests that adding lime, as was done in
Test 4, renders the arsenic less teachable
from both the soil and the resulting kiln
ash.
Table 7 summarizes the trace metal dis-
tributions among the incinerator discharge
streams, expressed as fractions
(in percent) of the amount of each metal
Test 1
tter (8/6/91)
Test 2
(8/8/91)
Test3
(8/13/91)
Test 4
(8/15/91)
Soil
Feedrate, kg/hr 55.7 55.5 54.2
Arsenic concentration, mg/kg 1,040 1,040 794
Arsenic feedrate, g/hr 57.9 57.7 43.0
Scrubber exit flue gas
Flowrate, dscm/min 49.8 47.6 48.6
Arsenic concentration, u.g/dscm 22.1 2.04 1.38
Arsenic emission rate, mg/hr 66.0 5.82 4.02
RE> % 99.89 99.9899 99 9907
Stack gas
Flowrate, dscm/min 67.4 65.2 63.6
Arsenic concentration, \ng/dscm 1.14 0.93 1.12
Arsenic emission rate, mg/hr 4.61 3.64 4.27
57.0
803
45.8
48.4
1.43
4.15
99.9909
63.2
1.16
4.40
RE,%
99.9920
99.9937
99.9900
99.9903
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Table 6. Trace Metals Analysis Results
Sample
As
Ba
Cd
Cr
Pb
Hg
Se
Test 1 (8/6/91)
Soil feed, mg/kg
Soil feed TCLP leachate, mg/L
Kiln ash, mg/kg
Kiln ash TCLP leachate, mg/L
Scrubber liquor, mg/L
Test 2 (8/8/91)
Soil feed, mg/kg
Soil feed TCLP leachate, mg/L
Kiln ash, mg/kg
Kiln ash TCLP leachate, mg/L
Scrubber liquor, mg/L
Test 3 (8/1 3/91)
Soil feed, mg/kg
Soil feed TCLP leachate, mg/L
Kiln ash, mg/kg
Kiln ash TCLP leachate, mg/L
Scrubber liquor, mg/L
Test 4 (8/1 5/91)
Soil feed, mg/kg
Soil feed TCLP leachate, mg/L
Kiln ash, mg/kg
Kiln ash TCLP leachate, mg/L
Scrubber liquor, mg/L
TCLP regulatory level, mg/L
1.040
2.2
653
5.8
8.5
1,040
2.2
619
3.8
12
794
2.5
619
4.1
10
803
0.11
1,100
1.2
6.0
5.0
56
0.89
60
0.76
0.16
66
0.57
60
0.70
0.23
48
0.80
64
0.78
0.21
43
0.18
74
0.12
0.26
100
fed to the incinerator for each test for all
metals analyzed, except arsenic which will
be discussed separately. The data in
Table 7 show that the kiln ash discharge
accounted for most of the barium and
lead fed in all tests. The scrubber liquor
accounted for about a factor of 10 less
(i.e., 10%) of the amount of barium and
lead fed than the kiln ash. The kiln ash
also accounted for the predominant frac-
tion of chromium fed in all tests, although
the scrubber liquor accounted for higher
relative fractions of chromium. The behav-
ior of cadmium was apparently inconsis-
tent from test to test. The addition of lime
to the soil, as done in Test 4, apparently
did not affect metals distributions to kiln
ash or scrubber liquor within the variability
of the data in Table 7. No mercury was
found in any kiln ash or scrubber liquor
sample. The "less than" fractions noted in
Table 7 correspond to sample analysis
PQLs. Most or all of the mercury fed likely
escaped the incineration system via the
scrubber exit flue gas.
Arsenic distributions are summarized in
Table 8 with the addition of the scrubber
exit flue gas discharge stream sampled.
The data show that the arsenic distribu-
tions were quite similar in Tests 1 through
3 in which soil alone was fed. Between
42% and 49% of the arsenic fed was
1.7
0.009
0.50
0.005
0.054
1.1
0.012
0.42
0.005
0.023
0.86
0.012
0.68
0.005
0.017
0.97
<0.005
0.85
<0.005
0.011
1.0
16
<0.007
9.7
< 0.007
0.15
19
<0.007
11
< 0.007
0.089
17
<0.007
11
<0.007
0.064
13
<0.007
14
<0.007
0.057
5.0
120
0.086
74
0.28
0.23
118
0.079
58
0.088
0.27
104
0.083
61
0.095
0.29
86
0.049
83
0.036
0.23
5.0
10
<0.002
< 1.0
< 0.002
0.007
5.8
<0.002
< 1.0
< 0.002
<0.002
5.4
<0.002
<1.0
<0.002
<0.002
6.2
<0.002
< 1.0
<0.002
<0.002
0.2
< 11
0.066
<12
0.059
<0.13
<11
0.057
16
0.065
<0.13
<11
0.063
1.5
0.062
0.14
15
0.058
<11
0.083
<0.13
1.0
<0.44
<0.005
<0.45
< 0.005
0.01
<0.44
<0.005
<0.45
< 0.005
<0.005
<0.43
<0.005
<0.46
<0.005
<0.005
<0.48
<0.005
<0.44
<0.005
<0.005
5.0
accounted for in the kiln ash (treated soil)
discharge. About 20% was collected in
the scrubber liquor. With lime added to
the soil (Test 4), the scrubber liquor frac-
tion decreased to 13% of the amount fed,
and the kiln ash fraction increased to 91%
of the amount fed. The scrubber exit flue
gas arsenic fraction was low, 0.1% or
less, in all four tests.
A clearer picture of the variation in rela-
tive arsenic distributions with incinerator
operation is possible when the data in
Table 8 are normalized by the total mass
balance closure achieved. Table 9 sum-
Table 7. Trace Metal Distributions
Metal distribution, % of metal fed
Sample
Test 1 (8/6/91)
Kiln ash
Scrubber liquor
Total
Test 2 (8/8/91)
Kiln ash
Scrubber liquor
Total
Test 3 (8/1 3/91)
Kiln ash
Scrubber liquor
Total
Test 4 (8/1 5/91)
Kiln ash
Scrubber liquor
Total
Ba
71
6
77
63
6
69
84
7
91
115
10
125
Cd
20
69
89
27
36
63
50
34
84
59
19
78
Cr
40
19
59
42
8
50
40
7
47
69
7
76
Pb
41
4
45
34
4
38
37
5
42
64
5
69
Hg
<7
<1
<8
<12
<1
<13
<12
<1
< 13
<11
<1
<12
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Table 8. Arsenic Distributions
Arsenic distribution, % of arsenic ted
Sample
Testl
(8/6/91)
Test 2
(8/8/91)
Tests
(8/13/91)
Test 4
(8/15/91)
Kiln ash 42
Scrubber liquor 18
Scrubber exit flue gas 0.1
Total 60
42
19
0.01
61
49
22
0.01
71
91
13
0.01
104
Table 9. Normalized Arsenic Distributions
Arsenic distribution, % of arsenic measured
Sample
Kiln ash
Scrubber liquor
Scrubber exit flue gas
Total
Apparent scrubber
Testl
(8/6/91)
70.2
29.6
0.17
100
99.44
Test 2
(8/8/91)
68.3
31.7
0.01
100
99.953
Test3
(8/13/91)
69.3
30.7
0.01
100
99.963
Test 4
(8/15/91)
87.8
12.2
0.01
100
99.937
collection efficiency
marizes the test arsenic distribution data
in this form. The distribution fractions in
Table 9 have been normalized to the total
amount of arsenic measured in all the
discharge streams analyzed. Thus, these
normalized values represent fractions that
would have resulted had mass balance
closure in each test been 100%. Use of
distribution fractions normalized in this
manner allows clearer data interpretation
because variable mass balance closure is
eliminated as a source of test-to-test data
variability. In other words, given that vari-
able and less than perfect mass balance
closure is invariably experienced, the use
of normalized distributions is a best at-
tempt to quantify metal partitioning phe-
nomena.
The normalized distributions in Table 9
clearly show that about 70% of the ar-
senic accounted for was discharged in the
kiln ash, or treated soil, in the three tests
feeding soil alone (Tests 1 through 3).
About 30% of the arsenic measured was
accounted for in the scrubber system li-
quor. A small fraction of the arsenic mea-
sured was accounted for by the scrubber
exit flue gas. However, with lime added in
Test 4, the kiln ash arsenic fraction in-
creased to 88% and the scrubber liquor
arsenic fraction decreased to about 12%.
The scrubber exit flue gas arsenic fraction
remained negligible. Clearly, the addition
of lime to the soil stabilized the arsenic,
tending to keep it in the kiln ash.
The apparent arsenic scrubber collec-
tion efficiencies for these tests are also
given in Table 9, where apparent scrub-
ber collection efficiency is defined as
Scrubber liquor fraction
Scrubber liquor fraction
+scrubber exit flue gas fraction
The data show that the Calvert scrub-
ber system achieved an average of
99.95% arsenic collection in Tests 2
through 4. The apparent collection effi-
ciency in Test 1 was lower at 99.44%.
However, the Test 1 result is suspected to
be an outlier.
Paniculate and HCI Emissions
Flue gas particulate levels measured at
the Calvert scrubber exit ranged from 9 to
19 mg/dscm (corrected to 7% O2). These
levels would represent the stack emis-
sions of a typical incinerator equipped with
a Calvert scrubber. These levels are sub-
stantially below the 180 mg/dscm (at 7%
O2) hazardous waste incinerator perfor-
mance standard. Apparent scrubber sys-
tem collection efficiencies calculated us-
ing the chlorine feedrates and measured
emission rates were 99.95%, or slightly
higher, in all tests. These levels exceed
the 99-% collection efficiency required by
the hazardous waste incineration perfor-
mance standards.
Conclusions
Test program data confirm that incin-
eration under the conditions tested resulted
in the elimination of the soil pesticide con-
taminants. No pesticide was detected in
any kiln ash (treated soil) sample. Based
on method PQLs, the decontamination ef-
fectiveness demonstrated was at least
99.38% for chlordane, 99.56% for p.p'-
DDE, 99.66% for p,p'-DDD, and 99.96%
for p,p'-DDT. In addition, pesticide DREs
of at least 99.9916% were achieved for
p,p'-DDT. None of the other pesticide con-
taminants was detected in the scrubber
exit flue gas, with lower bound DREs,
corresponding to method PQLs, ranging
from at least 99.87% for chlordane to at
least 99.92% for p,p'-DDD.
Arsenic REs of 99.99% were achieved
with the Calvert scrubber under the condi-
tions tested feeding soil alone. Adding lime
to the soil did not measurably improve
arsenic RE.
Trace metal concentrations in TCLP
leachates of both untreated soil and kiln
ash (treated soil) were significantly below
corresponding TC regulatory levels for all
metals except arsenic. Soil leachate ar-
senic concentrations were 40% to 50% of
the regulatory level. Kiln ash leachate ar-
senic concentrations were near or above
arsenic's TC regulatory level, suggesting
that treated soil could or would be a TC
hazardous waste. Adding lime to the soil
can significantly lower both the soil and
resulting incineration kiln ash leachate ar-
senic concentrations.
Nominally 70% of the arsenic measured
in the incinerator discharge was in the kiln
ash of all tests in which soil alone was
fed; about 30% was in the scrubber li-
quor; and a negligible fraction was in the
scrubber exit flue gas. In the test in which
lime was added to the soil, the kiln ash
arsenic fraction increased to about 90%;
about 10% was in the scrubber liquor;
and a negligible fraction was in the scrub-
ber exit flue gas The Calvert scrubber
apparent arsenic collection efficiency was
nominally 99.95% and was not affected
by lime addition. Particulate levels at the
Calvert scrubber exit were nominally 10 to
20 mg/dscm at 7% O2, well below the haz-
ardous waste incinerator performance
standard of 180 mg/dscm at 7% O2. Calvert
scrubber apparent HCI collection efficien-
cies were 99.95% or greater, above the
8
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hazardous waste incinerator performance
standard of 99%.
In summary, test results suggest that
conventional rotary kiln incineration in a
unit equipped with a high-efficiency scrub-
ber system, such as the Calvert system
tested, would be an appropriate treatment.
Elimination of contaminant organochlorine
pesticides from the soil and destruction of
the contaminant at a ORE of 99.99% were
achieved. Arsenic REs of greater than
99.96% were achieved in the system with
the Calvert scrubber in normal operation.
The hazardous waste incinerator particu-
late and HCI performance standards were
easily achieved.
Incineration treatment of soils with ar-
senic concentrations in the range of the
concentrations of the soil tested may re-
sult in the treated soil being a TC hazard-
ous waste. However, adding lime to soil
before incineration can significantly reduce
the teachability of the kiln ash arsenic in
the TCLP test.
The full report was submitted in fulfill-
ment of Contract No. 68-C9-0038, Work
Assignment 2-1, by Acurex Environmental
Corporation under the sponsorship of the
U.S. Environmental Protection Agency.
•U.S. Government Printing Office: 1993 — 750-071/60228
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-------
A. Siag, S.J. Fournier, Jr., and LR. Waterland are with Acurex Environmental
Corporation, Jefferson, AR 72079.
R.C. Thurnau is the EPA Project Officer (see below). H.O. Wall was the
Technical Project Monitor for the test program
The complete report, entitled "Pilot-Scale Incineration of Contaminated Soil
from the Chemical Insecticide Corporation Superfund Site," (Order No.
PB93-155968; Cost: $27.00, subject to change) will be available only
from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
EPA/600/SR-93/036
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