United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Cincinnati OH 45268
Research and Development
EPA-600/S2-84-048 May 1984
Project Summary
Trial Burn Protocol Verification
at a Hazardous Waste
Incinerator
P. G. Gorman and K. P. Ananth
Field tests were undertaken at the
Cincinnati Metropolitan Sewer District
(MSD) hazardous waste incinerator for
the purpose of verifying the U.S. Envi-
ronmental Protection Agency's (EPA's)
trial burn protocol and to conduct an
environmental a'ssessment. The
incinerator tested was equipped with a
rotary kiln rated at 55 x 10s kJ/hr and a
cyclone furnace rated at 65 x 106 kJ/hr.
Air pollution control was provided by a
venturi scrubber and sieve tray tower.
Two types of waste were fired during
the tests, one was a pesticide-contain-
ing waste and the second was a high
chlorine content waste. Test results
indicated that a 99.99% destruction and
removal efficiency (DRE) was achieved,
as required by the Resource Conserva-
tion and Recovery Act (RCRA)
regulations for the selected principal
organic hazardous compounds
(POHCs). However, the incinerator did
not meet the particulate standard of
180 mg/dscm nor the HCI removal
efficiency of 99%. It is believed that the
malfunction of the demister and the low
pH of the absorber solution were the
probable reasons for the higher
particulate loading and the low HCI
removal efficiency, respectively.
Several recommendations have been
made with respect to the trial burn
protocol and the sampling and analysis
procedures.
This Project Summary was developed
by EPA's Industrial Environmental
Research Laboratory, Cincinnati, OH,
to announce key findings of the
research project that is fully document-
ed in a separate report of the same title
(see Project Report ordering informa-
tion at back).
Introduction
The EPA's Industrial Environmental
Research Laboratory, Cincinnati, spon-
sored a program to evaluate the
hazardous waste trial burn protocol and
to conduct an environmental assessment
of the Cincinnati MSD hazardous waste
incinerator. Midwest Research Institute
(MRI) carried out the program fcr EPA, as
a subcontractor to Rockwell International
Corporation.
This summary report presents a
description of the MSD incinerator facility,
a summary of the sampling and analysis
program, a discussion of the test results,
and recommendations of the study
Complete descriptions and discussion of
test results are contained in the project
final report.
Description of the Facility
The Cincinnati MSD hazardous waste
incinerator is located at 1600 Gest Street
in Cincinnati. A schematic diagram of the
incinerator is given in Figure 1. The
symbols enclosed by circles in Figure 1
represent sampling points. As shown in
the figure, the incinerator is equipped
with a rotary kiln rated at 55 x 106 kJ/hr
and a cyclone furnace rated at 65 x 106
kJ/hr. Liquid wastes were fired
throughout the testing even though the
kiln is designed to handle solid or
semisolid wastes. The kiln and cyclone
furnace are connected to a single
combustion chamberthat is 4.15 m (13.5
ft) diameter by 12 2 m (40 ft) high This
chamber provides residence time for the
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Quench
Water
Auxiliary
Fuel Oil
Liquid Waste
Feed
L
Rotary
Kiln
1
1
>
5 |
Venturi
Scrubber
Combustor
Ash Gate]
J_
Cyclone
Furnace
J
Slowdown
Ash Damper \
To Lagoon
Sampling Points
SIA. SIB - Liquid Waste Feed
Sa*. SIB - Auxiliary Fuel Oil
Si - Ash Sluicing
St - Scrubber B/owdown
S5 - Quench Water
Se - Stack
Figure 1. Schematic diagram of the Cincinnati MSD incinerator.
combustion gas and is normally
maintained at 982°C (1800°F).
Gases exiting the combustion chamber
are immediately quenched with water
and pass into the venturi scrubber and
then flow upward through the sieve tray
scrubbing tower. Liquids fed to the
venturi scrubber and sieve tray absorber
should be maintained at 6.0 pH for HCI
removal. A vane-type mist eliminator is
located at the top of the absorber. Cooled
gases from the absorber are exhausted
through the induced draft fan into a
stainless steel stack. Liquid effluent from
the scrubbing system goes to the
treatment plant, and bottom ash is
sluiced with water out to a lagoon.
Sampling and Analysis Program
The sampling of the incinerator
involved testing the incinerator with two
different liquid wastes, one categorized
as a pesticide-containing waste and the
other as a high chlorine content waste.
These two wastes were separately fired
during two series of tests. The first series
of incinerator tests was conducted at
three different temperatures (899, 1093,
and 1316°C) and two residence time
ranges (1.5 to 2.2 sec and 3.3 to 3.7 sec),
whereas the second test series was
carried out at the same three
temperatures but only at one residence
time range (1.5 to 2.2 sec). These
operating parameters (residence time
and temperature) were varied to evaluate
the effect of these parameters on POHC
destruction and removal efficiency (ORE).
A total of nine test runs, six during the
first series and three during the second,
were performed in this program.
Samples were taken, as shown in
Figure 1, from the following process
streams: feed waste, fuel oil, ash.
scrubber effluent, quench water, an
stack gases. Analysis of these sample
was performed with the main objective
of determining ORE for the six selecte
PQHCs, the particulate grain loading i
the stack, the HCI removal efficiency, th
emission levels of volatile trace metal
CO, NOx, and hydrocarbons. Th
sampling and analysis procedures use
were either EPA methods or thos
approved by the EPA Project Office
According to the RCRA regulations o
January 23, 1981, the incinerator i
required to achieve 99 99% ORE fo
POHCs, 99% HCI removal efficiency (fo
waste containing more than 0 5°
chlorine), and a particulate emission of n
more than 180 mg/dscm (corrected t
12% C02). For each waste feed, si
POHCs were selected and these are a
follows'
Selected POHCs
First Waste
Chloroform
Carbon tetrachloride
Tetrachloroethylene
Hexachloroethane
Hexachlorobenzene
Hexachlorocyclopentadiene
Second Waste
Trichloroethane
Tetrachloroethane
Bromodichloromethane
Pentachloroethane
Hexachloroethane
Dichlorobenzene
Except for hexachlorobenzene and
hexachlorocyclopentadiene, the selec-
tion of POHCs was based on the EPA
ranking system, which takes into consid-
eration the heat of combustion of the
POHC and its concentration in the waste.
With this ranking system, any POHC with
a low heat of combustion is automatically
assigned a high rank (difficult to
incinerate), regardless of its concentra-
tion in the waste. Hexachlorober)zene
and hexachlorocyclopentadiene, how-
ever, were selected as POHCs because
they were present at high concentration
levels and were of particular interest
either to EPA or the MSD.
Test Results
Based on the testing effort, the DREs
for the POHCs of interest, the HCI
removal efficiency, the particulate
concentration in the stack gas, and other
results were obtained. These results are
summarized in the full report. The
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incinerator achieved 99.99% ORE for the
selected POHCs with the exception of
bromodichloromethane at an operating
temperature of 899°C (1650°F). The
paniculate standard of 180 mg/dscm
was not achieved, probably because of
the demister malfunction. The required
HCI removal efficiency of 99% was also
not achieved; this could be due to the low
pH of the scrubber solution and some
uncertainties associated with the
sampling and analysis method for HCI.
The concentrations of POHCs in the
scrubber effluent and bottom ash were
below detection limits in all runs but one.
Conclusions/
Recommendations
The test burn and environmental
assessment were successfully
completed. By and large, the trial burn
protocol was found to be workable.
However, since a major objective of
the program was to evaluate the trial burn
protocol, identify problems, and suggest
recommendations, the following recom-
mendations are being made.
• The acquisition and storage of a
sufficient quantity of waste to enable
testing throughout a trial burn test
period could pose difficulties. One
option for overcoming this problem
would be to direct trial burns to
wastes containing POHCs that are
more difficult to incinerate, and
allowing wastes with POHCs that are
less difficult to incinerate to be
burned without a trial burn. Also one
could limit the duration of a trial burn
to a 2-hr period in order to conserve
waste. The key consideration
however, would be to ensure that
the POHCs of interest are in suffi-
cient concentrations in the waste to
enable detection at the stack after
they have undergone 99.99%
destruction. Our experience indi-
cates that a minimum concentration
of 100 ppm in the waste would
enable detection in the stack if
sampled over a 2-hr period.
• A trial burn must consist of three
replicate tests.
• The sampling protocol for the
incinerator waste feed, scrubber
effluent, and bottom ash should be
clarified to explain how such
samples should be taken. It is
recommended that, whenever
possible, an integrated sample be
taken for liquid waste feeds
consisting of taking subsamples at
15-min intervals. For scrubber
effluent and bottom ash, grab
samples should be adequate.
• Selection procedures for POHCs
need to be -clarified. In its present
form, the protocol relies on the EPA
ranking system, which emphasizes
the heat of combustion and
minimizes the importance of concen-
tration. However, concentration
becomes an important factor if one is
interested in identifying products of
incomplete combustion
A sampling technique needs to be
developed for volatile POHCs.
Metals analysis in the waste feed
samples could pose a problem since
the semisolid phase present in some
of the samples could not be effec-
tively digested. EPA is presently
developing better digestion methods.
P. G. Gorman andK. P. Ananth are with Midwest Research Institute, Kansas City,
MO 64110.
Donald A. Oberacker is the EPA Project Officer (see below}.
The complete report, entitled "Trial Burn Protocol Verification at a Hazardous
Waste Incinerator, "(Order No. PB 84-159 193: Cost: $22.0O. 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:
Industrial Environmental Research Laboratory
U.S. Environmental Protection Agency
Cincinnati. OH 45268
U S GOVERNMENT PRINTING OFFICE. 1984 - 759-015/7692
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
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