xvEPA
United States
Environmental Protection
Agency
EPA/540/S5-88/002
January 1989
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
Technology Demonstration
Summary
Shirco Electric Infrared
Incineration System at the
Peak Oil Superfund Site
Under the auspices of the
Superfund Innovative Technology
Evaluation or SITE Program, a critical
assessment is made of the
performance of the transportable
Shirco Infrared Thermal Destruction
System* during three separate test
runs at an operating feedrate of 100
tons per day. The unit was operated
as part of an emergency cleanup
action at the Peak Oil Superfund site
in Brandon, Florida. The report
includes a process description of the
unit, unit operations data and a
discussion of unit operations
problems, sampling and analytical
procedures and data, and an overall
performance and cost evaluation of
the system.
The results show that the unit
achieved destruction and removal
efficiencies (DREs) of polychlo-
rinated biphenyls (PCBs) exceeding
99.99% and destruction efficiencies
(DEs) of PCBs ranging from 83.15%
to 99.88%. Acid gas removal
efficiencies were consistently
greater than 99%. Particulate
emissions ranged from 171 to 358
mg/dscm, exceeding 180 mg/dscm
during two of the four tests. The
Extraction Procedure (EP) Toxicity
Test on the furnace ash exceeded
the RCRA EP Toxicity Characteristic
standard for lead. Small quantities of
tetrachlorodibenzofuran (TCDF) were
detected in one of the four stack gas
samples. Also detected were low
levels of some semivolatile organics
and a broader range of volatile
organics, which can be considered
products of incomplete combustion
(PICs). Ambient air monitoring
stations detected quantities of PCBs,
which appear to be caused by the
transport of ash from the ash pad to
the ash storage area. Waste feed and
ash samples were not mutagenic
according to the standard Ames
Salmonella mutagenicity assay. Unit
costs are estimated to range from
$196 to $795 per ton with a
normalized cost per ton of $425 for
the Peak Oil cleanup.
This Summary was developed by
EPA's Risk Reduction Engineering
Laboratory, Cincinnati, OH, to
announce key findings of the SITE
Program demonstration that is fully
documented in three separate reports
(see ordering information at back).
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Introduction
The SITE Program demonstration test
of the Shirco infrared incineration system
was conducted from July 1, 1987 to
August 4, 1987 at the Peak Oil
Superfund site in Brandon, Florida during
a removal action by EPA Region IV The
Region had contracted with Haztech,
Inc , an emergency removal cleanup
contractor, to incinerate approximately
7,000 tons of waste oil sludge
contaminated with PCBs and lead after
determining that high temperature
thermal destruction of the nonrecyclable
sludge was capable of destroying the
PCBs in a cost-effective and
environmentally sound manner. Metals
that concentrated in the ash residue
would be dealt with after the thermal
destruction of the sludge. The removal
action offered an ideal opportunity for the
SITE program to obtain specific
operating, design, analytical, and cost
information to evaluate the performance
of the unit under actual operating
conditions. Also, the SITE program
studied the feasibility of utilizing the
Shirco transportable infrared incinerator
as a viable hazardous waste treatment
system at other sites throughout the
country. To this end, specific test
objectives of the Shirco system were:
• To determine the system's destruction
and removal efficiency (ORE) for
PCBs.
• To report the unit's ability to
decontaminate the solid material being
processed and to determine the
destruction efficiency (DE) for PCBs
based on the PCB content of the
furnace ash
• To evaluate the ability of the unit and
its associated air pollution
control/scrubber system to limit
hydrochloric acid and particulate
emissions
• To determine whether heavy metals
contaminants in the waste feed are
chemically bonded or fixated to the
ash residue by the process.
• To determine the effect of the thermal
destruction process in producing
combustion byproducts or products of
incomplete combustion (PICs).
• To determine the impact of the unit
operation on ambient air quality and
potential mutagenic exposure.
• To provide unit cost data for effective
development of a cost/economic
analysis for the unit
• To document the mechanical
operations history of the unit and
analyze and provide potential solutions
to chronic mechanical problems
Facility and Process
Description
Solid waste processed at the Peak Oil
site was incinerated in a transportable
infrared incinerator, designed and
manufactured by Shirco Infrared
Systems, Inc. of Dallas, Texas and
operated by Haztech, Inc. of Decatur,
Georgia. The overall incineration unit
consists of a waste preparation system
and weigh hopper, infrared primary
combustion chamber, supplemental
propane-fired secondary combustion
chamber (afterburner), emergency
bypass stack, venturi/scrubber system,
exhaust system, and data collection and
control systems, all mounted on
transportable trailers. The system
process flow and the overall test site
layout are presented schematically in
Figure 1.
Solid waste feed material is processed
by waste preparation equipment
designed to reduce the waste to the
consistency and particle sizes suitable
for processing by the incinerator After
transfer from the waste preparation
equipment, the solid waste feed is
weighed and conveyed to a hopper
mounted over the furnace conveyor belt.
A feed chute on the hopper distributes
the material across the width of the
conveyor belt. The feed hopper screw
rate and the conveyor belt speed rate are
used to control the feedrate and bed
depth.
The incinerator conveyor, a tightly
woven wire belt, moves the solid waste
feed material through the primary
combustion chamber where it is brought
to combustion temperatures by infrared
heating elements. Rotary rakes or
cakebreakers gently stir the material to
ensure adequate mixing, exposure to the
chamber environment, and complete
combustion. When the combusted feed
or ash reaches the discharge end of the
incinerator, it is cooled with a water spray
and then is discharged by a screw
auger/conveyor to an ash hopper.
The combustion air to the incinerator is
supplied through a series of overfire air
ports located at various locations along
the incinerator chamber; combustion air
flows countercurrent to the conveyed
waste feed material
Exhaust gas exits the primary
combustion chamber and flows into the
secondary combustion chamber where
propane-fired burners combust ar
residual organics present in the exhau
gas. The secondary combustion chambi
burners are set to burn at a predf
termmed temperature. Secondary air
supplied to ensure adequate exces
oxygen levels for complete combustioi
Exhaust gas from the secondar
combustion chamber is quenched by
water-fed venturi/scrubber to remov
particulate matter and acid gases; th
exhaust gas is then transferred to th
exhaust stack by an induced draft fai
and finally discharged to the atmosphere
The mam unit controls and dat
collection indicators comprising the dal
collection and control system are house
in a specially designed van
An emergency bypass stack i
mounted in the system directly upstreai
of the venturi/scrubber for the diversic
of hot process gases under emergenc
shutdown conditions
Results and Discussion
A detailed summary of the SIT
demonstration test results is presented i
Table 1. Based on the test objective
outlined in the Introduction, the followin
results and conclusions were obtained.
PCB Destruction and Removal
Efficiency
PCBs were analyzed in the solid wast
feed, furnace ash, scrubber effluer
solids, stack gas, scrubber liquid effluen
and scrubber water inlet. The DR
calculation for PCBs is based on th
following:
w. - w
DRE =
w.
x 100
where: Win = mass rate of PCBs fed t
incinerator
wout = mass emission rate c
PCBs in stack gas
The unit achieved a DRE for PCBs c
99.99%.
It should be noted that the unit wa
operated to produce an ash tha
contained 1 ppm or less of PCB. Th
PCB concentration in the waste feed t
the unit varied from 5.85 to 3.48 ppr
during the tests These low PCI
concentrations in the waste feed were thi
result of mixing the original oily wast
having up to 100 ppm of PCBs with th
PCB-free surrounding soil, lime, an<
sand so that the resulting material couli
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Control
Van
kW
Feed Hopper
i Feed Module
As/i
Discharge
Figure 1.
Primary
Combustion Chambe
I Secondary
*" Combustion Chamber
Chemical Chevron
Recycle Recycle ;
Pumps Pumps
Slowdown Water to POTW
Peak Oil Incinerator Unit
be handled and processed as a solid
waste It was not possible to calculate the
ORE beyond two decimal places
because of the detection limits
associated with the analytical procedures
employed
Decontamination of Solid Waste
and Destruction Efficiency
Residual PCBs in the furnace ash were
below the 1 ppm operating standard,
ranging from 0 007 ppm on August 1 to
0 900 ppm on August 3. DE was
determined by the formula
W
w
DE =
W
x 100
where wm = mass rate of PCBs fed to
incinerator
W0ut = mass rate of PCBs in
stack gas, furnace ash,
and scrubber effluent
A basis for calculating DE was based on
the PCB concentrations in the waste feed
and the furnace ash The DE or removal
of the PCBs from the waste feed ranged
from 99 88 wt% (August 1) to 83.15 wt%
(August 3)
Acid Gas Removal
Measured HCI emission rates ranged
from less than 0.8 to 8.6 g/hr. Since the
chlorine concentration in the solid waste
feed was below the 0.1% detection limit,
it was impossible to determine actual HCI
removal efficiency However, SC>2
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Table 1. Site Demonstration Test Results Summary
811/87
Stack Gas
HCI ppmv
SO2, ppmv
HCI, g/hr
SO2, g/hr
Particulates (@ 7% O2), mg/dscm
PCB, {iglhr
Ash
PCB, ppm
Pb, ppm
EP Tox (Pb), mg/L, ppm
TCLP (Pb), mg/L, ppm
8/2/87
8/3/87
<0051
099
<08
27.40
358
57 70
0.01
7100
250
0.01
060
41 80
860
1070.0
211
17450
0.240
6000
28.0
0.01
0.22
0.96
290
22.0
173
58 10
0.900
6400
36.0
002
8/4/87
Waste Feed Characteristics
Moisture, wt %
Ash, wt %
HHV, Btu/lb
PCB, ppm
Pb, ppm
Chlorine, ppm
Sulfur, ppm
Chlorine (as HCI), kg/hr
Sulfur (as SO2), kg/hr
EP Tox (Pb), mg/L, ppm
TCLP (Pb), mg/L, ppm
16.63
6977
2064
5 850
5900
0000
25300
<5
200
27.00
860
7606
6980
1639
3.850
4900
<1000
17800
<5
132
2900
2 50
1424
72.40
1728
5.340
5000
<1000
18900
<5
138
. -
300
1437
75 21
2018
3480
4400
<1000
16700
<5
125
2400
3.50
020
091
2 70
20.6
171
12620
0540
6200
36.0
001
Operating Conditions
Waste Feedrate (avg. daily), kg/hr
ORE (PCB), wt %
DE (PCB), wt %
Primary Combustion Chamber
Exhaust Temperature (avg ), F
Residence Time, mm
Secondary Combustion Chamber
Chamber Temperature (avg ), F
Residence Time, sec
Acid Gas Removal Efficiency,
wt % SO?
3328
9999
9988
T797
19
1886
>3
>999
3287
99.99
9377
1836
19
1887
>3
>99 1
3626
99.99
83.15
1922
18
1889
>3
>999
3600
99.99
84.48
1885
19
1907
>3
>999
emissions were less than 1100 g/hr, with
an average 149 kg/hr SC>2 feedrate
giving an average removal of SC>2 in
excess of 99% SOg is more difficult to
remove than HCI in a caustic scrubber,
and the tests show that HCI removal
should be in excess of the 99%
determined for SC>2 removal.
Particulate Emissions
The particulate emissions during the
first day were 358 mg/dscm The unit
was cleaned and mechanical
adjustments were made resulting in an
emission rate of 211 mg/dscm during the
second day The emissions during the
third day were 172 mg/dscm (average of
duplicate measurements) These values
exceeded the RCRA standards during
two of the four sampling periods.
Particulate emissions were about 60%
lead, when analyses of all samples were
averaged
Leaching Characteristics
The solid waste feed, furnace ash, and
scrubber effluent solids were subjected
to the EP Toxicity and proposed TCLP
tests to evaluate the toxicity
characteristics of these materials
The EP Toxicity and the TCLP data
present a contradictory picture regarding
leaching of metals The EP Toxicity data
did not indicate that the process
"encapsulates" or ties up heavy metals
(lead) in the ash to prevent leaching. The
EP Toxicity data show that lead content
in the ash was 30 ppm and exceeded the
5 ppm toxicity characteristic standard.
The measured lead content of leachates
for feed material and ash are almost
equal, indicating that the process
appears not to affect leaching
characteristics for lead
In contrast to the EP Toxicity data, the
TCLP data show that the lead content for
both the feed and ash were less than the
proposed toxicity characteristic standard
of 5 ppm Measured lead concentrations
were an order of magnitude lower in the
TCLP leachate (about 2 ppm comparec
to about 30 ppm for EP Toxicity)
The significant differences in results
from these two analytical techniques
have been documented in a recent Oak
Ridge National Laboratory report (ORNL
"Leaching of Metals from Alkaline
Wastes by Municipal Waste Leachate,"
ORNL TM-1 1050, March, 1987) II
appears that the differences in the tesl
procedures and alkalinity of the matrix
provide a difference in the ph
environment that is sufficient to affect the
solubility and leachability of heavy
metals, particularly lead
Products of Incomplete
Combustion
Small quantities of products ol
incomplete combustion (PICs) were
identified in the sampled streams frorr
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the unit. No polychlorinated dibenzo-
dioxms (PCDDs) or polychlorinated
dibenzofurans (PCDFs) were identified in
any of the sampled streams above
detection limits with the exception of
trace quantities (2 1 ng) of
tetrachlorodibenzofuran (TCDF) found in
the stack gas sampled on August 2.
Low levels of some semivolatile
organic compounds were identified in all
streams. These compounds were
primarily phthalates, which may be the
result of contamination from plastic
components in the process, sampling
equipment, or laboratory apparatus
Other semivolatile compounds included
aromatic, polyaromatic, and chlorinated
aromatic hydrocarbons. Low levels of
pyrene, chrysene, anthenes,
naphthalenes, and chlorinated benzene
were identified in the waste feed stream;
although possible PICs, their presence
must be discounted to some extent,
because they were originally introduced
into the unit with the waste feed
Low concentrations of volatile organics
were measured in the stack gas and
included halogenated methanes,
chlorinated organics, and aromatic
hydrocarbons including BTX compounds
No volatile organics were identified in the
water streams. Low levels (ppb) of
chlorinated hydrocarbons and BTX
compounds were measured in all solid
streams. Low levels of BTX compounds,
carbon disulfide, chloroform, ditri-
chlorofluoromethane, and tnchloro-
fluoromethane, dichloroethane, and
trichloroethane, and methylene chloride
were identified in the waste feed
Methylene chloride, a solvent used
during testing, was also detected in
laboratory and field blanks These
compounds, although possible PICs,
must also be discounted to some extent
based on their introduction to the unit
from an external source and because of
possible contamination
Ambient Air Sampling and
Mutagenic Testing
Ambient air monitoring stations placed
upwind and downwind of the Shirco unit
were designed to collect airborne PCB
contaminants Based on the downwind
sampler data, it appears that the Peak Oil
site boundaries limited the location of the
downwind sampler to an area that was
significantly exposed to fugitive
emissions during the transport of ash
from the ash pad to the ash storage area
Samples of the waste feed and ash
were collected on August 2 and
forwarded to the EPA Health Effects
Laboratory, Research Triangle Park,
North Carolina for mutagenic testing. The
results of these tests indicate that
although the samples contain hazardous
contaminants, they are not mutagenic
based on the standard Ames Salmonella
mutagenicity assay.
Cost/Economic Analysis
Several cost scenarios examined were
based on a model for a Shirco unit
operation equivalent in processing
capacity to the unit that operated at Peak
Oil, and on cost data available from
Shirco and other sources. The economic
analysis concludes that in using currently
available Shirco transportable infrared
incineration systems, commercial
incineration costs will range from an
estimated $196 per ton for a Shirco unit
operation at an 80% on-stream capacity
factor to an estimated $795 per ton for
the operation at the Peak Oil site at a
19% on-stream capacity factor. A
normalized total cost per ton of $425
represents a more realistic interpretation
of the costs accrued to the Peak Oil
cleanup action based on a 37% on-
stream capacity factor
Unit Problems
A review of the Haztech, EPA
Technical Assistance Team (TAT), and
EPA logbooks and progress reports, plus
discussions with unit and project
personnel, provided a summary of
mechanical and operating problems
encountered in this first application of a
full-scale commercial Shirco
incineration system at a Superfund site
These problems were categorized by
unit operating sections, and a profile of
the major problem areas within the unit
were defined and analyzed to ascertain
the reasons for and possible solutions to
these specific operational difficulties The
review revealed that materials handling
and emissions control were the most
significant problem areas affecting
operation of the unit Prior to the
operation of such a unit, extensive
pretest analysis should be conducted on
the waste feed matrix The
characteristics of the feed, including the
nature of contaminants plus the feed's
effect on incineration system chemistry,
must be defined to allow appropriate
assembly of the unit The unit must be
equipped with the proper feed
preparation system and materials
handling capabilities and adequate
emissions control capacity and
effectiveness. At the Peak Oil site, the
solidified sludge feed continually
agglomerated, clogged, bridged, and
jammed feed preparation and handling
equipment. The high levels of lead
contaminant and the excessive carryover
of calcium and magnesium salts were a
continuous source of problems for the
emissions control system, which had
difficulty in meeting stack emissions
criteria.
Conclusions and
Recommendations
Based on the above data and
discussions, the following conclusions
and recommendations can be made
concerning the operation and
performance of the transportable Shirco
infrared thermal destruction system.
1 The unit achieved DREs of PCBs
greater than 99.99%. Detection limits
were used for this calculation so
actual DREs were greater.
2.The unit achieved DEs of PCBs
ranging from 83.15 to 9988%. The
unit was operated to produce an ash
that contained 1 ppm or less of PCB.
3. Acid gas removal efficiencies were
consistently greater than 99%.
Particulate emissions during two
days of testing were 358 mg/dscm
and 211 mg/dscm, which contained
60% lead The unit's emissions
control system experienced
particulate removal problems due to
a combination of excessive fines
carryover from the waste feed matrix
and scrubber-washer and an overall
emissions control system design that
was not able to operate efficiently at
abnormally high particulate loadings
As a result, two of the four samples
taken exceeded the 180 mg/dscm
RCRA standard
Pretest analysis of the waste feed
and its combustion and emissions
control chemistry and mechanisms
must be performed to identify
potential emissions control problems
A more flexible and adaptable
emissions control system should be
developed that can respond to and
control a wider range of particulate
and stack gas flows
4. The furnace ash failed to meet the
toxicity characteristic standard for
lead for the EP Toxicity Test
Procedure. Although the ash passed
the similar standard for the proposed
TCLP, its failure under EP Tox
indicates that the unit did not
immobilize lead in the ash product.
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5 Small quantities of PICs were
identified in the sampled streams
from the unit In addition to trace
quantities of TCDF on one sample,
low levels of semivolatile
compounds, including aromatic,
polyaromatic, and chlorinated
aromatic hydrocarbons were
identified Low concentrations of a
broader range of volatiles including
halogenated methane, chlorinated
organics, and BTX compounds were
also identified
6 Ambient air monitoring stations
detected quantities of RGBs, which
appear to be caused by the wind
transport of ash resulting from the
nearby roadway Waste feed and
ash samples were not mutagemc
based on the standard Ames
Salmonella mutagenicity assay
7 Overall costs ranged from $196 per
ton with the unit operating at an 80%
on-stream capacity (292 days per
year) to $795 per ton with the unit
operating at a 19% on-stream
capacity (70 days per year) A
normalized cost per ton for the Peak
Oil cleanup was estimated at $425
In addition to the particulate
emissions control system problems,
waste feed handling and materials
handling problems consistently
affected the unit's ability to treat the
waste feed at design capacity
Pretest analysis of the waste feed
and its handling characteristics must
be performed to identify and design
for any potential materials handling
or feeding problems that the waste
matrix may present at a specific site
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The EPA Protect Manager, Howard Wall, is with the Risk Reduction Engineering
Laboratory, Cincinnati, OH 45268 (see below).
The complete report consists of two volumes, entitled "Technology Evaluation
Report, SITE Program Demonstration Test, Shirco Infrared Incineration
System, Peak Oil, Brandon, Florida:"
"Volume I" (Order No. PB 89-125 991/AS: Cost: $21.95, subject to
change) discusses the results of the SITE demonstration
"Volume II" (Order No. PB 89-116 0241 AS; Cost: $42.95, subject to
change) contains the technical operating data logs, the sampling and
analytical report, and the quality assurance project plan/test plan
These two reports will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA22161
Telephone: 703-487-4650
A related report, entitled "Applications Analysis Report: Shirco Infrared Thermal
Destruction System," which discusses application and costs, is under
development.
The EPA Protect Manager 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
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
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n 5 ..rs-
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