United States Solid Waste and EPA-542-R-97-012
Environmental Protection Emergency Response March 1998
Agency (5102G) www.epa.gov
clu-in.com
v°xEPA On-Site Incineration:
Overview of Superfund
Operating Experience
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NOTICE
This report was prepared by the U.S. Environmental Protection Agency (EPA). Neither the U.S.
Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied,
or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any
information, apparatus, product, or process disclosed, or represents that its use would not infringe
privately-owned rights. Reference herein to any specific commercial product, process, or service by trade
name, trademark, manufacturer, or otherwise does not imply its endorsement, recommendation, or favoring
by the U.S. Government or any agency thereof. The views and opinions of authors expressed herein do not
necessarily state or reflect those of the U.S. Government or any agency thereof.
Compilation of this material has been funded wholly or in part by the EPA under EPA Contract Nos.
68-W4-0004 and 68-W5-0055.
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TABLE OF CONTENTS
Section Page
INTRODUCTION 1
OVERVIEW OF ON-SITE INCINERATION TECHNOLOGY 1
INCINERATOR DESIGNS 2
Rotary Kiln Incinerators 3
Liquid Injection Incinerators 5
AIR POLLUTION CONTROL SYSTEMS DESIGNS 7
Cyclone Separators 7
Gas Conditioners (Quench) Systems 8
Baghouses 9
Wet Scrubbers 10
Mist Eliminators 11
PERFORMANCE OF ON-SITE INCINERATION 11
Performance - Automatic Waste Feed Cutoffs Systems 13
Performance - Weather-Related 13
MATRIX CHARACTERISTICS 14
COSTS OF ON-SITE INCINERATION 15
COMMUNITY INVOLVEMENT 15
REGULATORY REQUIREMENTS 16
Residuals Management 17
Guidance 17
Proposed Regulations 18
FIGURES
^igure Page
1 Typical Rotary Kiln Incinerator 3
2 Typical Liquid Injection Incinerator 6
3 Typical Cyclone 8
4 Typical Reverse-Air Baghouse 10
5 Typical Venturi Scrubber 11
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TABLES
Table Page
1 General Information on the Selected Sites 20
2 Selected Matrix Characteristics and Values for Operating Parameters 25
3 Selected Stack Gas Emissions Measured During Trial Burn 27
4 Summary of Cost Data for Each Site 29
5 Current and Proposed Incinerator Standards 32
in
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INTRODUCTION
Incineration has been used as a remedy at more than 40 Superfund sites. Information on cost and
performance of incineration can be valuable to remedial project managers (RPMs) and other decision
makers responsible for future site cleanup projects. To date, reports on cost and performance for this
technology have been limited.
Fifteen case studies were prepared to obtain additional data on operating experience for completed
projects. These studies are published under a separate cover. The case studies are available on the Internet
through the Federal Remediation Technologies Roundtable home page at http://www.frtr.gov under the
topic "publications." The case studies are also available through EPA's CLU-IN homepage on the Internet
at http://www.clu-in.com.
This report was prepared: 1) to summarize the case studies, 2) to provide technology descriptions under
one cover, and 3) to make general observations based on individual applications. It includes an overview
of incineration design, air pollution control systems, and regulatory requirements. General information on
the selected sites is provided in Table 1. All tables cited in the text are presented at this end of this report.
Summary tables include information on specific sites, corresponding to specific site case studies that will
be published at a later date in a second report.
OVERVIEW OF ON-SITE INCINERATION TECHNOLOGY
Incineration uses controlled flame combustion to volatilize and destroy organic contaminants and is used to
treat a variety of media, including soils, sludges, liquids, and gases. An incinerator consists of a burner,
which ignites the supplied fuel and combustibles in the waste feed in a combustion chamber. Efficiency of
combustion depends on three main factors of the combustion chamber: temperature, residence time of the
waste material in the combustion chamber, and turbulent mixing of the waste material. Thermal
destruction of most organic compounds occurs at temperatures between 1,100°F and 1,200°F. The
majority of hazardous waste incinerators are operated at temperatures that range from 1,200°F to 3,000°F
in the burning zone. To achieve thermal destruction, residence time usually ranges from 30 to 90 minutes
for solid waste and 0.5 to 2.0 seconds for liquid waste. Turbulent mixing is important because the waste
and fuel must contact the combustion gases if complete combustion is to occur. Sufficient oxygen must be
present and is supplied as ambient air or as pure oxygen through an injection system [4].
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A typical incineration systems consists of several distinct units. The first unit is the kiln or primary
combustion chamber, into which waste is fed and in which initial volatilization and destruction of
contaminants takes place. In many incineration systems, gases formed during incineration in the kiln
include uncombusted organics or combustion by-products, referred to as products of incomplete
combustion (PIC). The PICs are drawn to a secondary combustion chamber (SCC) designed to increase
the efficiency of destruction of PICs or to incinerate a liquid feed stream. Residual bottom ash produced
during the incineration process typically exits the kiln through a gravity drop and is then cooled before
subsequent management.
From the SCC, the off-gas is routed through an air pollution control system (APCS), which may include a
variety of units, depending on the types of contaminant being treated, the concentrations of those
contaminants in the waste feed, and the design of the kiln. The APCS cools the off-gas and removes
particulates or acid gases produced during the incineration process [3]. Gases are drawn through the
incineration system by an induced-draft fan, which maintains a negative pressure within the system. A
negative pressure reduces the potential that fugitive emissions will be produced and draws gases through
the system at a specified flow rate to promote efficient destruction and removal of contaminants.
Particulate matter collected in the APCS is removed periodically for subsequent management. Treated
exhaust gas exits the system through a stack.
On-site incinerators are usually transported to sites by rail or flatbed truck. Such systems are prefabricated,
transported to the site in pieces, and assembled on site. The size of mobile, on-site incinerators usually is
restricted by the capacity of the transport vehicles. The maximum outside diameter of the mobile kilns
observed for these case studies was approximately 14 feet.
INCINERATOR DESIGNS
Two primary incinerator types were evaluated in the case studies: rotary kiln incinerators and liquid
injection incinerators. A third design, an infrared incinerator, was used at the Rose Township Dump site.
However, this design is no longer used commercially in this country (please refer to the case study of that
site for more information). The following subsections discuss rotary kiln incinerators and liquid injection
incinerators. The designs are discussed in more detail in the case studies along with cost and performance
data for each application.
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Discharge to
Quench or Heat
R ecovery
C o m b u stion
Air
Waste Liquj.d_s
A uxillary
Fuel
Waste Solids,
Containers or
Slu dges
.1 .0 - 3.0
Seconds Gas
Residence
Time
R efractory
R ota rv Kiln
Afte rb u rn e r
Figure 1 : Typical Rotary Kiln Incinerator (adapted from EPA-530-R-94-014)
Rotary Kiln Incinerators
Rotary kilns were used at 12 case study sites. The rotary kilns were used to treat most forms of waste,
including solids, liquids, sludges, and debris. Figure 1 is a schematic diagram of atypical system.
Rotary kilns are cylindrical, refractory-lined steel shells supported by two or more steel trundles that ride
on rollers, allowing the kiln to rotate on its horizontal axis. The refractory lining is resistant to corrosion
from the acid gases generated during the incineration process [4]. The kilns in the case studies ranged
from 6 to 14 feet in diameter and 25 to 110 feet in length. The burners for the kilns ranged from 10
million British thermal units (BTU) per hour to 120 million BTU per hour.
Rotation rate of the kiln and residence time for solids are inversely related; as the rotation rate increases,
residence time for solids decreases [4]. Residence time for the waste feeds in the case studies varied from
30 to 80 minutes, and the kiln rotation rate ranged from 30 to 120 revolutions per hour. Another factor
that has an effect on residence time is the orientation of the kiln [4]. Kilns are oriented on a slight incline,
a position referred to as the rake. The rake typically is inclined from 2° to 4° from the horizontal.
Rotary kiln incinerators are designed with either a co-current or a countercurrent chamber. In the
countercurrent design, waste is introduced at the end opposite the burner and flows down the rake toward
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the burner, while combustion gases are drawn up the rake. In a co-current design, the waste feed is
introduced at the burner end and flows down the rake, while the combustion gases are also drawn down the
rake. Most rotary kiln incinerators in the case studies were of the co-current design, which provides for
more rapid ignition of the waste feed and greater gas residence time for combustion than does the
countercurrent design [4].
Wastes are fed directly into the rotary kiln, either continuously or semicontinuously. Solids can be fed by
such devices as ram feeders, auger screw feeders, or belt feeders. Liquid wastes can be injected with steam
or by atomizing nozzles directly into the kiln through the main burner. Liquid wastes can also be injected
by a waste lance or mixed with solid wastes [4].
The rotary kilns in the case studies were equipped with a secondary combustion chamber (SCC)
(afterburner) to facilitate more efficient destruction of volatile organic contaminants. An SCC is a steel
shell lined with refractory material and equipped with a burner. The SCCs included in the case studies
have outside diameters ranging from 7 feet to 12 feet and lengths ranging from 30 feet to 38 feet. Off-gas
from the kiln is routed through the SCC and typically has a residence time of 1 to 3 seconds. The SCC
typically will operate at a higher temperature than the kiln. In the SCCs included in the case studies, the
typical operating temperature ranged from 1,700°F to 2,000°F.
For one case study (the Sikes site), the design calculations showed that the incinerator optimal throughput
could not be achieved because of the size of the SCC. A second SCC was installed in parallel with the
first, increasing the throughput rate by 30 percent. This added cost was offset by the increased throughput
rate, which reduced the length of time the incinerator was operated.
An oxygen-enhanced combustion system was used at one site to increase the efficiency of the rotary kiln.
The combustion process is more efficient because the desired combustion efficiency is achieved at a lower
residence time, thereby increasing throughput of waste. A potential drawback to the use of an oxygen-
enhanced system is the possibility of generating higher concentrations of nitrogen oxide (NO,) in
emissions, compared with the concentrations in emissions generated by an unenhanced system.
Feeding of excessive quantities of highly combustible or explosive wastes to a rotary kiln may cause
overpressurization. Sustained overpressurization may lead to releases of untreated gases to the
environment through seals or other conduits. To avoid sustained overpressurization in the kiln, several of
the incinerators employed an emergency relief stack (also known as a dump stack) between the SCC and
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the APCS. If a circumstance should arise that would allow positive pressure to build up in the kiln, such
as induced draft fan cutoff, the dump stack would be opened, and combustion gases would be vented from
the SCC to the atmosphere. Although there is a small risk from this activity, it is less than the cumulative
risk that results from consistent overpressurization. To avoid release of untreated emissions, an
Environmentally Safe Temporary Emergency Relief System® (ESTER8) was installed at four of the case
study sites. ESTER® is a dump stack that is equipped with a burner that thermally treats the vented gases.
Liquid Injection Incinerators
Liquid injection incinerators were used at two case study sites. These incinerators are used to treat
combustible liquid and liquid-like waste, including sludges and slurries. A typical liquid injection
incinerator consists of a waste burner feed system, an auxiliary fuel system, an air supply system, and a
combustion chamber. Figure 2 is a schematic diagram of a typical liquid injection incinerator.
Liquid wastes were fed into the combustion chamber through waste burner nozzles, which atomized the
waste and mixed it with air that ignited and burned in the combustion chamber. Typical residence time in
the combustion chamber ranged from 0.5 second to 2 seconds, and the temperature of the combustion
chamber ranged from 1,300°F to 3,000°F.
If the energy content of the waste is not high enough to maintain adequate ignition and incineration
temperatures, a supplemental fuel, such as fuel oil or natural gas, may be pumped from a storage tank into
the combustion chamber to augment the ignition potential of the waste mix. Air necessary for combustion
is provided to the burner by a fan [5].
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25 - 250%
Excess Air
D isc ha rg e to
Quencher Wa ste
Heat R ecove ry
A to m iz ing
Stea m o r T
Air I
P rim a ry
C o m bu stio n
Air
2600F-3000F
0.3 - 2.0
Seconds Main
Comb ustio n G as
Residence Time
150Tr-F-2200-F
C ro ss S e ctio n
Figure 2: Typical Liquid Injection Incinerator (adapted from EPA-530-R-94-014)
Liquid injection incinerators are used to dispose of aqueous and nonaqueous wastes that can be atomized
through a burner nozzle. Liquid wastes, sludges, or slurries that contain large amounts of solids must be
filtered before they are stored in feed tanks that are usually pressurized with nitrogen. A control valve and
flow meter are used to feed waste to the incinerator [5].
The combustion chamber for a liquid injection incinerator may be as simple as a cylinder lined with
refractory material and can be oriented either vertically or horizontally. Liquid feed rate to the incinerator
may be as high as 1,500 gallons per hour. Impingement of flames on the wall of the combustion chamber
is undesirable because it can lead to corrosion of the refractory material and loss of heat; therefore, location
of the burner is an important design criterion. Liquid injection incinerators also can use the oxygen-
enhanced burners discussed in the section describing the rotary kiln, although none were encountered in
the case studies [5].
A hybrid version of the liquid injection incinerator was used at one site, Rocky Mountain Arsenal. The
submerged quench incineration system used a vertical downfired liquid incinerator. The liquid waste was
injected at the top of the furnace into a gas flame. After incineration, the products of combustion were
forced downward and cooled in a liquid quench tank. That process aided in washing out particulates and
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removing by-products from the exhaust gases. The high temperature in the incinerator melted
noncombustible components, metals, and salts that had formed on the walls, so that those compounds
flowed down the walls of the incinerator and cooled in the quench chamber [5].
AIR POLLUTION CONTROL SYSTEMS DESIGNS
APCSs are used on incinerators to control particulate matter and acid gas emissions. The APCS must be
designed specifically for each incinerator, taking into consideration a number of factors including the
incinerator type and operation as well as the waste stream to be incinerated and contaminants of concern.
APCSs often include multiple components, operating in sequence, to effectively control emissions, which
vary in physical and chemical properties.
In the various case studies, five components in different combinations made up the APCSs. The
components were cyclone separators, gas conditioners (quench) systems, baghouses, scrubbers, and mist
eliminators. A description of these unit operations, and observed and potential effects on incinerator cost
and performance related to APCS designs, is provided below.
Cyclone Separators
Cyclones typically are conical or cylindrical chambers that stand vertically. Particles suspended in a gas
stream usually enter the cyclone near the top and follow a spiral path along the wall of the chamber. The
vortex causes particles to accelerate to the wall under centrifugal forces. The particles stay in the thin
laminar layer of air next to the wall, and gravity pulls the particles down to a dust hopper at the bottom of
the cyclone. The treated gas reverses direction near the bottom and rises through the central tube of the
vortex to exit at the top. Periodically, dust is removed for subsequent management [2].
Cyclones can remove only particles that are 5 micrometers (//m) in diameter or larger. Efficiency in
removing particles depends on the velocity of the gas, the rate at which the gas changes direction, and the
size, distribution, density, and composition of the particles. Efficiency can be increased by increasing the
swirling velocity of the gas, which is done by reducing the diameter of the cyclone chamber or increasing
the flow rate of the gas [2].
Three of the incinerators in the case studies were equipped with cyclone separators to remove large
particulates from off-gases. Cyclone separators operate at high temperatures and have no moving parts;
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they also operate at low cost and require little maintenance. Cyclones in the case studies were placed
immediately downstream of the kiln or other combustion chamber. Figure 3 is a schematic diagram of a
typical cyclone.
Gas Conditioners (Quench) Systems
Gas conditioners often are placed at the first stage of an APCS to enhance the performance of the
components that follow. Gas conditioning operations may include use of a cooling fan, humidifying of the
gas, and injection of reagents. The most common gas conditioner is the quench system, which was used in
all of the incinerator systems in the case studies [2].
Clean Gas Outlet
Ascending Vortex
Inlet
Clean Gas Outlet
Radial Flow
Dust Laden
Cone Outlet Gas
Cone Apex
Path of Dust
Tangential Inlet
Axial Inlet
Figure 3: Typical Cyclone (adapted from EPA-530-R-94-014)
In a quench system, the gas enters the quench vessel and water is sprayed into the gas. The temperature of
the gas falls as the water evaporates. To protect later components of the system that are sensitive to high
temperatures, quench systems often are placed at the first stage of an APCS. In addition, if there is a
potential to form dioxins and furans, the rapid cooling of gas in the APCS can minimize this potential by
quickly lowering the temperature below the range that favors their formation. When that is the desired
effect, the quench system immediately follows the SCC. Droplets of water and particles tend to adhere to
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the walls in the quench vessel; therefore, some quench systems use a film of water to wash particles from
the wall. The wash water then collects at the bottom of the vessel [2].
Bughouses
Baghouses (or fabric filters) are used as part of the APCS to remove suspended particles from off-gases
and were used at five of the case study incinerators. A baghouse consists of numerous filter bags made of
a porous fabric on which dust particles collect and form a porous cake. Because this cake has the highest
particulate collection efficiency, the efficiency of the filter is usually lowest at startup and after the bags
have been cleaned. Off-gases entered the baghouse at relatively low temperatures, approximately 350 to
450°F. To prevent condensation that can plug and corrode the filter bags, the temperature must be within
the range of temperature at which the fabric works most efficiently and above the dew point of water and
common acid gases. The temperature also should be below any temperature in the range at which dioxins
and furans can form.
Two common designs for baghouses are the reverse-air and the pulse-jet types, named for the cleaning
systems they employ. Figure 4 is a schematic diagram of atypical reverse-air baghouse. Reverse-air
baghouses have cylindrical bags into which the flue gas is directed. As the gas flows through the fabric,
dust collects on the inside of the bags. Periodically, the air flow is reversed, causing dust cakes to fall from
the bag to a hopper below. The cleaning procedure occurs at a low gas velocity, which does not subject
the bags to excessive wear and tear. Pulse-jet baghouses also have cylindrical bags, but with an additional
internal frame. The frame, called a cage, holds the bags while the gas flows from outside the bag through
the fabric to the inside of the bag. The cleaning process for a pulse-jet baghouse tends to be more vigorous
than that for the reversed-air baghouse; therefore, the lifetime of the pulse-jet bag is not as long. In both
designs, the dust cakes are removed from the hoppers periodically for subsequent management [2].
The gas-to-cloth ratio is the ratio of the volumetric flow rate of the gas to the filter surface area and is
expressed as the ratio of cubic feet of gas per minute passing through one square foot of cloth (acfm/ft2).
Pressure drop is an important measurement for a baghouse. A very high pressure drop may indicate
that the bags are plugging or binding. Low pressure drops may indicate there are holes or leaks in the
fibers [2].
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Wet Scrubbers
Wet scrubbers are commonly used to remove particulate matter and soluble gases from the stack emissions.
The designs observed in the case studies were venturi scrubbers to remove particulate matter, followed by
packed-tower scrubbers to remove soluble gases.
Venturi scrubbers are a section of duct the diameter of which narrows and then widens, forming a throat
(see Figure 5). At the sites that used venturi scrubbers, a recirculated liquid usually was injected into or
just upstream of the throat. The gas accelerated in the throat, causing atomization of the liquid. In some
systems, spray nozzles also were used to atomize the liquid on injection. The mixture of particles and
droplets decelerates as it moves into the expansion section, and the droplets begin to aggregate. Gravity
pulls some of the droplets out of the gas stream, and the mixture then passes through a mist eliminator that
removes more droplets from the gas [2].
Valve
dosed
111
dean
Gas
deaning
Gas
Bags Distended
Due to Inflation
Sewn in
Rings
r- Tension
Adjustment
Valve
J dosed
Dust Collecting Mode
Dirty Gas to
Other
. Modules for
r\ Cleaning
*~y
Dust Out
Figure 4: Typical Reverse-Air Baghouse (adapted from EPA-530-R-94-014)
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Gas Inlet
Liquid Inlet
Converging Section
DvergngSectiorr*
Elbow
Figure 5: Typical Venturi Scrubber (adapted from Buonicore, A.J. and W.T. Davis, Air Pollution
Engineering Manual, 1992)
In a packed tower scrubber, a bed of packing material, usually open plastic spheres, fills a section of the
scrubber vessel. The gas stream enters at the base and flows up through the bed of packing material. The
liquid enters at the top and flows down. The packing material increases the surface area that allows the gas
to contact the liquid. The liquid collects at the bottom, and the gas exits near the top. The liquid is
removed and can be treated in a number of ways [2].
Mist Eliminators
Fine droplets of liquid are removed using mist eliminators. Mist eliminators were used at five case study
incinerators. In these systems, the mist eliminators always were located downstream from the scrubbers.
Most of the mist eliminators in the case studies used wave plates or meshes of fine wire, designed to
provide both a large surface area for collection of droplets and a high void space through which the gas
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flows. The droplets collided with the plates or wire and fell to the bottom of the structure, where they
collected until removal for subsequent management. Mist eliminators usually are cleaned with a mixture
of fresh water and recycled water.
PERFORMANCE OF ON-SITE INCINERATION
Based on available performance information, all 15 case study projects achieved their established
performance standards. Performance standards for an incineration system are determined during a trial
burn, when the system is operated at worst-case conditions, while still meeting applicable emissions limits
(see Regulatory Requirements). Samples of the waste feed and measurements of emissions taken while the
system is operated during such conditions then are used to determine the degree of destruction and removal
of the constituents of concern. During the trial burn, which typically requires 2 to 5 days to complete,
critical operating parameters are measured and then are used to establish values for the operating
parameters for the post-trial burn operation of the system such as minimum combustion chamber pressure,
maximum feed rate for each waste type, maximum carbon monoxide (CO) emissions, and various
limitations for APCSs ( for example, minimum pressure drop across a baghouse). During the operation of
the incinerator, these parameters are monitored continuously to ensure that they remain within the limits set
during the trial burn. It is assumed that operating the system within the range of all the acceptable
operating limits will ensure that the incineration system meets the required performance standards.
During the trial burn, principal organic hazardous constituents (POHC) are used to measure the destruction
and removal efficiency (DRE) of the incinerator (the detailed requirements for determining DRE are
presented in regulations at Title 40 of the Code of Federal Regulations (40 CFR) 270.62). The POHCs are
selected for each site to be representative of the waste burned at that site. The selected POHCs must be at
least as difficult to destroy as the other contaminants of concern so that the destruction of the POHCs
indicates adequate destruction and removal of all organic contaminants of concern. POHCs may be
introduced, or spiked, into the waste and may be different than the actual contaminants if, for example, the
concentrations of contaminants in the waste are hard to measure at the concentrations expected. During
the trial burn, the concentration of POHCs in all influent streams and stack gas emissions is measured and
used in conjunction with measurements of feed rate and stack gas flow rate to calculate the DRE. Table 2
presents available information on stack gas emissions measured during trial burns for the case study sites.
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Performance - Automatic Waste Feed Cutoffs Systems
The incinerator system is equipped with an automatic waste feed cutoff (AWFCO) system that
immediately stops waste feed into the incinerator if any of the operating parameters are outside the
acceptable ranges established during the trial burn. AWFCOs also are activated if concentrations of
certain indicator contaminants in the exhaust gases exceed their respective limits. Those contaminants can
include CO and total hydrocarbons (THC), which are indicators of incomplete combustion and are
measured by continuous emissions monitors (CEMs), and hydrogen chloride (HC1) and free chlorine gas
(C12). AWFCOs help to ensure safe operation of an incinerator and allow the owner or operator to make
adjustments to ensure that the incinerator is operating within its established operating range.
Information was requested from site owners or operators about the numbers of AWFCOs at each site and
the cause of the cutoffs. Information about the frequency of AWFCOs was available for 5 of the 15 sites.
The most frequent cause of AWFCOs identified by RPMs and other site managers was overpressurization
of the kiln. For example, at the Times Beach site, overpressurization was a daily occurrence. In many
cases, site managers identified excess moisture in the waste feed as the reason for the overpressurization.
Other significant causes of AWFCOs included stack gas concentrations of oxygen (Vertac and Sikes sites)
and concentrations of oxygen at the exit of the SCC (Old Midland site) that fell below the minimum
acceptable concentrations. Possible causes of those AWFCOs include changes in the waste feed from that
identified by the initial characterization. For example, if the concentration of organic compounds and the
BTU value of a waste feed are higher than expected, the excess level of oxygen to ensure complete
combustion decreases, triggering an AWFCO. Other comparatively frequent causes of AWFCOs included
temperatures in the SCC that fell below acceptable limits (Old Midland site), feed rate above the maximum
limit (Sikes site), and stack gas velocity that exceeded the maximum limit (Old Midland site).
Performance - Weather-Related
Weather affected the operation of several of the systems in the case studies. At the Yakima site,
shakedown activities were scheduled during the winter, with average temperatures of 25 °F. The cold
weather delayed startup activities, and the incinerator projects fell behind schedule. Power outages due to
strong storms were problems at Times Beach and Bayou Bonfouca. At these sites, a decision was made to
shut down the incinerators during storms. Finally, at the MOTCO site, heat caused electrical switchgear to
overheat, cutting of the induced draft fan and resulting in a shutdown of the incinerator; site personnel
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speculated that this event could have been avoided if the equipment had been located in an air-conditioned
building.
MATRIX CHARACTERISTICS
In preparing the case studies, EPA collected information about matrix characteristics that affect cost or
performance of incineration. Table 3 provides a summary of available information about matrix
characteristics. Pretreatment was employed at the majority of the case study sites. Such pretreatment
included crushing, milling, and mixing the waste with lime or sand to adjust the particle size, moisture
content, or pH of the solids. Site personnel at the Old Midland site attributed a lack of problems with on-
site incineration largely in part to thorough characterization of the wastes that were fed to the incinerator.
Conversely, at some sites where the matrix characteristics had not been adequately characterized during the
remedial investigation (RI) or other site investigation, incinerator operation was adversely impacted. For
example, at the Bridgeport site, the waste feed was interrupted when drums and other debris encountered
during the excavation of an on-site lagoon were fed to the incinerator and became entangled in the
conveyer belt. In other cases, excess soil moisture and the presence of contaminants or matrices that had
not been anticipated based on the results of site investigations resulted in problems with operation. At the
MOTCO site, design and construction were based on information collected during the RI and feasibility
study (FS). Severe slagging problems occurred when incineration began, either because of the presence of
contaminants that had not been identified during the RI or because of the failure to define soil
characteristics accurately. Disagreements about the performance of the incinerator led to court action and a
suspension of remedial activities at the site.
At the Bridgeport site, overpressurization of the kiln caused several AWFCOs. Frequent
overpressurization also occurred at Times Beach. Personnel working at the site attributed this to excess
moisture in the soil and suggested excavating the soil when it was dry. When time constraints mandated
excavation of moist soil, alternative methods, such as the addition of lime, were used to dry the soil.
At three sites, MOTCO, Bridgeport, and Sikes, slagging was encountered. Slagging was attributed to the
presence of unacceptably high concentrations of inorganic contaminants or minerals in the waste feed.
Slagging decreased throughput capacity as the internal diameter of the kiln was reduced by slag. At the
Sikes site, a recirculating waterfall configuration at the bottom of the SCC was designed to catch and cool
falling pieces of slag. The technique worked well for small pieces of slag, but larger pieces created large
amounts of steam, which rose into the kiln and caused overpressurization.
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Matrix characteristics affected operation of the incinerator at the Vertac site. At this site, the feed
consisted of solid and liquid phases, and the heat content of the solid and liquid phases of waste differed.
The variable heat content of the solid and liquid waste streams required continuous balancing of the
volume of the two waste streams that were fed to the incinerator to maintain a constant temperature in the
kiln. Another experience at Vertac was that the calcium hydroxide reacted with HC1, a by-product of the
incineration at this site, creating calcium chloride residues which then clogged the spray drier. Sodium
hydroxide, which did not cause clogging, was then used as the neutralizing agent.
COSTS OF ON-SITE INCINERATION
Cost information was obtained for 14 of the 15 sites included in the case studies. The level of detail of
cost information varied from site to site. Detailed breakdowns of costs were available for 7 of the 15 sites.
At those sites, the costs of treatment ~ excluding before- and after-treatment costs ~ ranged from $120 to
$410 per ton. Many of the sites where detailed information was not available were operated by potentially
responsible parties (PRPs).
Table 4 presents a summary of the available cost data for the case study sites. Treatment costs were
calculated on a unit-basis when data on the cost for treatment-only were available. Where detailed costs
were not available, total costs of the site cleanup are given.
COMMUNITY INVOLVEMENT
Community involvement in the case study projects varied both in terms of the level of involvement and the
numbers and type of issues raised. Key issues included concern that the on-site incinerators, which had
been built for the purpose of remediating the site, would become a permanent facility and be used to treat
off-site wastes; concern over noise; and concern about emissions from the incinerator. At some sites,
citizens were generally supportive of the project. Examples of community involvement for the case study
projects are provided below.
At the Times Beach site, many citizens voiced concern that the incinerator would begin incinerating waste
from sites outside the state. Citizens near the Sikes site also expressed concern that the incinerator would
become permanent. Before incineration began at either site, residents in the vicinity of the Rose Disposal
Pit site and the Times Beach site expressed concern that noise might disturb the community. At Times
Beach, most activities took place inside buildings, and officials at the Rose Disposal Pit site worked with
15
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local officials to limit any effects of the project on the community; therefore, the local community at each
site did not perceive noise as a problem. At the Bayou Bonfouca site, which is in a residential area,
members of the local community identified noise as an issue. A silencing system installed on the stack and
an induced-draft fan was used to allow 24-hour operation of the incinerator without disturbing residents.
At the Vertac site, incineration was halted when community groups, Greenpeace and the Government
Accountability Project, concerned about the incineration of wastes containing dioxins obtained restraining
orders.
REGULATORY REQUIREMENTS
On-site incineration selected as part of a remedy under the Comprehensive Environmental Recovery,
Conservation, and Liability Act (CERCLA) must comply with applicable or relevant and appropriate
requirements (ARARs) (see section 121 of CERCLA). These ARARs include federal, state, and local
regulations. A discussion of several relevant federal regulations is provided below.
Because much of the waste that is incinerated at Superfund sites is defined as hazardous waste, there are
several potential ARARs under the Resource Conservation and Recovery Act (RCRA). Incinerators at
Superfund sites that burn hazardous wastes must meet the RCRA incinerator regulations (40 CFR parts
264 and 265, subpart O). Incinerator performance standards include:
• At least 99.99 DRE for principal organic hazardous constituents
• At least 99.9999 percent DRE for wastes that contain dioxins and furans
• Less than 0.08 grains per dry standard cubic foot (gr/dscf) of particulate matter (PM)
• Less than 4 pounds per hour HC1 or less than 1 percent of HC1 in the stack gas
On-site incinerators that are used to dispose of poly chlorinated biphenyls (PCBs) may also be subject to
the requirements under the Toxic Substances Control Act (TSCA) set forth in 40 CFR part 761. The
regulations require that wastes that contain more than 50 milligrams per kilogram (mg/kg) of PCB and that
are incinerated meet a DRE of 99.9999 percent. Compliance with this DRE is determined as it is under
RCRA regulations.
16
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Ash or other residues that are generated by incineration are subject to the RCRA Subtitle C requirements if
they are determined to be hazardous wastes under 40 CFR part 261. Any RCRA hazardous waste is also
subject to the land disposal restrictions under 40 CFR part 268.
Wastewaters generated by on-site incineration (for example, scrubber water) and discharged to waters of
the U.S. must comply with ARARs under the Clean Water Act. Standards for the discharge of process
wastewater from incinerators include:
Requirements of the National Pollutant Discharge Elimination System, which regulates
the amount of contaminants discharged directly to a surface-water body (40 CFR parts 122
and 125)
Requirements for standards for pretreatment that regulate the amount of contaminants
discharged to a publicly owned treatment works (40 CFR part 403)
Residuals Management
At three sites, residues were required to be managed as hazardous waste. At the Vertac and Rocky
Mountain Arsenal sites, the waste feed was a listed hazardous waste, and, therefore, residuals, such as ash,
salts, and scrubber water, were hazardous waste. At Bridgeport, the metals present in the ash caused the
ash to fail analysis by the toxicity characteristic leaching procedure (TCLP); the ash, therefore, required
stabilization and disposal off site in a landfill permitted under RCRA Subtitle C. At those three sites, the
unit costs were higher than for the other sites evaluated. At most of the sites, however, ash was landfilled
on site after analysis by TCLP. Most of the liquid waste was treated at an on-site wastewater treatment
system and subsequently discharged to surface water.
Guidance
In addition to the regulations listed above, EPA has developed several guidance manuals to assist federal
and state government officials and the regulated community in assessing the performance of incineration.
Although the guidelines in these manuals are not ARARs, they may assist RPMs or decision makers in
interpreting compliance with ARARs or provide technical clarification of the intent of ARARs. The
guidance manuals include:
EPA. 1991. Implementation Document for Boiler and Industrial Furnace Regulations.
November.
17
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EPA. 1990. Quality Assurance/Quality Control (QA/QC) Procedures for Hazardous
Waste Incineration. EPA/625/6-89/023. January.
EPA. 1989. Hazardous Waste Incineration Measurement Guidance Manual. Center for
Environmental Research Information. EPA/625/6-89/021. June.
U.S. Environmental Protection Agency (EPA). 1989. Guidance on Setting Permit
Conditions and Reporting Trial Burn Results. Office of Solid Waste and Emergency
Response. EPA/625/6-89/019. January.
Proposed Regulations
At the time this document was published, EPA had proposed revised regulations applicable to hazardous
waste combustion (HWC) devices, specifically incinerators and cement kilns and light-weight aggregate
kilns that treat hazardous wastes. The maximum achievable control technology (MACT) approach defined
in Title 3 of the 1990 Clean Air Act Amendments is being applied in the development of the new
emissions standards. The proposed rule specifically includes "devices [that] consist of mobile units (such
as those used for site remediation and Superfund clean-ups)." [4]
The pollutants for which emission standards are proposed under the MACT rule are:
• Dioxins and Furans (polychlorinated dibenzodioxins [PCDD] and polychlorinated
dibenzofurans [PCDF])
• Mercury (Hg)
• Semivolatile metals (cadmium and lead)
• Low volatility metals (antimony, arsenic, beryllium, and chromium)
• Total chlorine (considering both HC1 and chlorine [C1J)
CO
PM
As proposed, the MACT rule would establish a floor standard based on the average performance of the
best 12 percent of existing sources (as indicated by an EPA review of existing incinerators). EPA may
elect to set more stringent, but technically achievable, beyond-the-floor standards for specific constituents,
depending on an evaluation of the incremental additional benefits and costs of such an approach.
18
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The proposed MACT rule governing HWC devices also would require the use of five continuous
emissions monitors (CEM):
CO
THC
• Oxygen (O2) (used for correction to 7 percent oxygen)
• Mercury (Hg)1
PM
The proposed MACT rule governing HWC devices was published in the FR on April 19, 1996. Because
of the complexity of the rule and the number of comments it elicited, EPA reevaluated the rule and issued
revised proposed technical standards on May 2, 1997. At the time this report was published, the proposed
rule had not yet become final. Table 5 shows current and proposed emissions standards that are potential
ARARs for remedial actions that involve on-site incineration.
Analysis of the proposed standards indicates that all the incinerators that were evaluated would have met
the proposed standards for particulate matter. The incinerators also would have met the standard for
carbon monoxide (which is not proposed to change). Bridgeport was the only site that required monitoring
for volatile and semivolatile metals; however, that incinerator would have been in compliance with the
proposed standards.
Overall the cases studied met their treatment objectives. Problems when encountered were primarily of an
operational nature. Although these problems slowed the incineration at these sites, they did not result in
increased risks to the community.
1 Although the use of Hg CEMs was proposed, it is not expected that EPA will require their use in
the final MACT rule. In a recent Federal Register (FR) notice [62 FR 67788; December 30, 1997], EPA
states "...As a result, the Agency now believes it has not sufficiently demonstrated the viability of Hg
CEMs as a compliance tool at all hazardous waste combustors and should not require their use.
Nonetheless, EPA still believes Hg CEMs can and will waste at some sources but does not have sufficient
confidence that all HWC conditions are conducive to proper operation of the Hg CEMs tested..."
19
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Table 1. General Information on the Selected Sites
(Page 1 of 5)
Site Name
Baird & McGuire, MA
Bayou Bonfouca, LA
Bridgeport Refinery and
Oil Services, NJ
Celanese Corporation
Shelby Fiber
Operations, NC
Incineration
System Design
Rotary kiln, SCC,
quench tower,
baghouse, wet
scrubbing system
Rotary kiln, SCC,
quench system, gas
conditioner,
scrubber, mist
eliminator
Rotary kiln, SCC,
cyclone separator,
venturi quench,
packed tower
scrubber, mist
eliminator
Rotary kiln, SCC,
quench duct,
baghouse, packed
bed scrubber system
Media (Quantity)
- Soil (2 10,000
tons)
- Sediment (1,5 00
cubic yards)
• Sediment
(169,000 cubic
yards)
• Lagoon
sediment and
sludge (138,350
tons)
• Debris (13,000
tons)
• Levee material
(12,550 tons)
• Lagoon oil
(3,850 tons)
• Soil (4,250 tons)
• Soil and sludge
(4,660 tons)
Principal
Contaminants
• Dioxin
• Volatile organic compounds
(VOCs)
• Polynuclear aromatic
hydrocarbons (PAHs)
• Pesticides
- PAHs
- PCBs
- VOCs
• Ethylene glycol
- VOCs
- PAHs
• Phenol
Comments
• Wide variety of contaminants.
• Volume of contaminated soil
underestimated by a factor of
three.
• Inadequate design caused
numerous mechanical
problems.
• Incineration operation
suspended twice because of
mechanical problems.
• Problems with demulsifying
complicated dewatering of
sediment.
• Smallest amount incinerated
among the case studies.
20
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Table 1. General Information on the Selected Sites
(Page 2 of 5)
Site Name
Coal Creek, WA
FMC Corporation -
Yakima, WA
Incineration
System Design
Rotary kiln, SCC,
baghouse, scrubber
Rotary kiln, SCC,
quench tank, venturi
scrubber, cooling
tower, packed bed
adsorber, ionizing
wet scrubber
Media (Quantity)
• Soil (9,7 15 tons)
- Soil (5,600
cubic yards)
Principal
Contaminants
- PCBs
• Pesticides
Comments
• Compliance with DRE
requirements was allowed to be
demonstrated without spiking,
because of the previous
performance of the incinerator,
and because it had a TSCA
permit.
• Frigid ambient air temperatures
caused delays in setting up the
incinerator, as shakedown
activities occurred during the
winter months (shakedown and
testing originally had been
scheduled for spring and
summer).
21
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Table 1. General Information on the Selected Sites
(Page 3 of 5)
Site Name
MOTCO, TX
Old Midland Products,
AR
Petro Processors, LA
Incineration
System Design
Rotary kiln, SCC;
second incinerator
with single liquid
injection combustion
chamber;
both had quench
system, gas
conditioner, wet
scrubber, mist
eliminator
Rotary kiln, SCC,
quench tower,
venturi scrubber,
baghouse, wet
scrubber
Horizontal liquid
injection incinerator,
quench tank, wet
scrubber, particulate
scrubber,
entrainment
separator
Media (Quantity)
• Soil (4,699 tons)
- Sludge (283
tons)
• Organic liquids
(7,568 tons)
• Aqueous waste
(10,471 tons)
• Soils, sludges,
and sediments
(102,000 tons)
• Organic liquids
and fumes
(213,376
gallons, as of
June 1997)
Principal
Contaminants
• Styrene tars
- VOCs
• Pentachlorophenol
- PAHs
• Chlorinated hydrocarbons
- PAHs
• Oils
Comments
• Mechanical problems, caused
in part by the lack of accurate
waste characterization, were
encountered.
• On-site incineration was
stopped in December 1991
because of a dispute between
the contractor and the
responsible party tons
incinerated.
• Remedy was changed to off-
site incineration, in part
because of the dispute and
mechanical problems.
• According to project managers,
this incineration project
encountered few problems
because of good waste
characterization .
• Incineration is used to treat free
product and emissions from a
groundwater pump and treat
system.
• Site personnel believe that the
operation has been relatively
trouble-free.
22
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Table 1. General Information on the Selected Sites
(Page 4 of 5)
Site Name
Rocky Mountain
Arsenal, CO
Rose Disposal Pit, MA
Rose Township Dump,
MI
Sikes Disposal Pits, TX
Incineration
System Design
Submerged quench
incinerator, quench
chamber, spray
dryer, venturi
scrubber, packed
tower scrubber
Rotary kiln, SCC,
cyclone separator,
baghouse, quench
towers, wet
scrubbing system
Infrared incinerator,
SCC, quench,
venturi scrubber,
packed-column
scrubber
Rotary kiln, SCC,
quench section,
venturi, two-stage
scrubber
Media (Quantity)
• Liquids (10.9
million gallons)
- Soil (5 1,000
tons)
• Soils, rocks, and
tree stumps
(34,000 tons)
• Soil and debris
(496,000 tons)
• Contaminated
water (350
million gallons)
Principal
Contaminants
• Organochloric and
organophosphoric
pesticides
- PCBs
- VOCs
- PCBs
- VOCs
• Semivolatile organic
compounds (SVOCs)
• Organic and phenolic
compounds
Comments
• Innovative design was used to
capture metal particulates.
• Recovered enough copper to
recycle.
• Incinerator used to treat more
than 5 0,000 tons of soil
contaminated with PCBs.
• An estimated 600 tons of
incinerator ash required
reincineration because it did
not meet requirements for on-
site disposal.
• Two SCCs in parallel were
required to maximize
throughput of incinerator.
• Steam generated by quenching
of slag caused
overpressurization in the kiln.
23
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Table 1. General Information on the Selected Sites
(Page 5 of 5)
Site Name
Incineration
System Design
Media (Quantity)
Principal
Contaminants
Comments
Times Beach, MO
Rotary kiln, SCC,
quench section,
venturi, two-stage
scrubber
Soil and debris
(265,000 tons)
Dioxin
The site served as a central
treatment facility for 27 sites in
the state of Missouri that were
contaminated with dioxin.
A release of untreated kiln
gases occurred when a storm
interrupted power to the
incinerator and blew out the
pilot lights on the emergency
relief vent system.
Vertac Chemical
Corporation, AR
Rotary kiln, SCC,
cyclone separators,
wet scrubbers
Still bottom
waste and soil in
drums (9,804
tons)
Dioxin
VOCs
Pesticides
In 1986, after several
unsuccessful trial burns, the
first contractor left the site and
the RP declared bankruptcy.
Two temporary restraining
orders were filed to stop the
incineration project in light of
public concern about the
incineration of dioxin-listed
waste; on-site incineration
proceeded with non-dioxin
wastes.
24
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Table 2. Selected Stack Gas Emissions Measured During Trial Burn
(Page 1 of 2)
Site Name
Limit
Baird & McGuire, MA
Bayou Bonfouca, LA
Bridgeport Refinery and Oil
Services, NJ
Celanese Corporation, NC
Coal Creek, WA
FMC Corporation- Yakima Pit,
WA
MOTCO, TX
Old Midland, AR
Petro Processors *, LA
Rocky Mountain Arsenal, CO
Rose Disposal Pit , MA
Average ORE (%)
Greater than or equal
to 99.99 for organic
constituents
Greater than or equal
to 99.9999 for dioxin
and PCB
contaminated media
99.99991
99.99
99.99995
99.9995
99.99994
99.999992
99.9999 for PCBs
99.99987
99.999988
99.9989
99.99987
Stack Particulates
(corrected to 7% oxygen)
Not greater than 0.08
gr/dscf
NA
0.0059
0.018
0.00359
0.000532
0.0014
0.052
0.0024
liquid mode: 0.0264
fume mode: 0.0018
0.0214
NA
Stack HC1
(Ib/hr)
Not greater than the
larger of either 41b/hr or
l%oftheHClinthe
stack gas prior to
entering any APCD
NA
0.035
3.97
O.02575
0.0205
0.0088
0.045
0.15
liquid mode: 0.190
fume mode: 0.01
0.2291
NA
Stack CO
(60-minute rolling average,
corrected to 7%oxygen)
Not greater than 100 ppmv
NA
1 ppm
4,500 g/hr
2 ppm
Below detection limit
18.44 ppm
0.0 ppm
13. 4 ppm
liquid mode: 1.7 ppm
fume mode: 3. 8 ppm
51.5 ppm
9.9 ppm
25
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Table 2. Selected Stack Gas Emissions Measured During Trial Burn
(Page 2 of 2)
Site Name
Rose Township Dump, MI
Sikes Disposal Pits, TX
Times Beach, MO
Vertac Chemical Corporation,
AR
Average DRE (%)
99.99982
99.9996
99.99998
99.99985
Stack Particulates
(corrected to 7% oxygen)
NA
0.0073
0.014
NA
Stack HC1
(Ib/hr)
NA
<0.027
0.014
NA
Stack CO
(60-minute rolling average,
corrected to 7%oxygen)
3.34ppm
1.0 ppm
0.0 ppm
NA
Incinerator is part of a groundwater treatment system that treats recovered liquid organic compounds and fumes from an air stripper.
26
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Table 3. Selected Matrix Characteristics and Values for Operating Parameters
(Page 1 of 2)
Site Name
Baird & McGuire, MA
Bayou Bonfouca, LA
Bridgeport Refinery and
Oil Services, NJ
Celanese Corporation,
NC
Coal Creek, WA
FMC Corporation-
Yakima Pit, WA
MOTCO, TX
Old Midland, AR
Petro Processors, LA
Medium
Classification
Unclassified
soil and sludge
Sediment
Unclassified
soil
Semiviscous
sludge
Unclassified
soil
Unclassified
soil and debris
Unclassified
soil and sludge
Unclassified
soil and sludge
Liquid
Moisture
Content (%)
9
52
NA
25
NA
NA
25 (varied
feed)
-40 (sludge)
-15 (soil)
Not
Applicable
Stack Gas
Flow During
Trial Burn
44,435 acfin
43,560 acfin
20,000 to
37,000 acfin
1,750 feet
per second
15,074 acfin
NA
42-1 17 acfin
12,500 dscf
NA
Primary
Combustion
Chamber
Residence
Time During
Trial Burn
NA
30-40 minutes
40-80 minutes
45 minutes
30 minutes
NA
15-90 minutes
NA
2 seconds
System
Throughput
During Trial Burn
25 tons/hr
28.6tons/hr
24 tons/hr
2.3 tons/hr
10 tons/hr
NA
12 tons/hr (solid)
512 Ibs/hr (quench
liquid)
825 Ibs/hr (organic
liquid)
18 tons/hr
0.735 tons/hr (liquid
mode)
Kiln Temperature
NA
1,094°F
l,200°Fto 1,600°F
1,500°F
l,700°Fto2,000°F
600°Cto 1,000°C
950°F
l,200°Fto 1,800°F
1, 600 °F (fume mode)
2,000 °F to 2,300 °F
(liquid mode)
27
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Table 3. Selected Matrix Characteristics and Values for Operating Parameters
(Page 2 of 2)
Site Name
Rocky Mountain
Arsenal, CO
Rose Disposal Pit, MA
Rose Township Dump,
MI
Sikes Disposal Pits, TX
Times Beach, MO
Vertac Chemical
Corporation, AR
Medium
Classification
Liquid
Sand, silt, and
clay
Unclassified
soil
Unclassified
soil, debris
Unclassified
soil, debris
Still bottom
waste in drums
Moisture
Content (%)
Not
Applicable
NA
13.1 to 14.2
10 to 12
7.8
Not
Applicable
Stack Gas
Flow During
Trial Burn
438 scfin
NA
NA
47,550 acfin
38,300 acfin
NA
Primary
Combustion
Chamber
Residence
Time During
Trial Burn
2 seconds
NA
10-60 minutes
45 minutes
60 minutes
40 minutes
System
Throughput
During Trial Burn
176 Ibs/min
50 tons/hr
6.9 tons/hr
46 tons/hr
3 1 tons/hr
NA
Kiln Temperature
l,750°Fto 1,900°F
NA
l,400°Fto 1,800°F
1,236°F
1,250°F
2,000°F
28
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Table 4. Summary of Cost Data for Each Site
(Page 1 of 3)
Site Name
Baird &
McGuire, MA
Bayou
Bonfouca, LA
Bridgeport
Refinery and
Oil Services,
NJ
Celanese
Corporation,
NC
Coal Creek,
WA
FMC
Corporation-
Yakima Pit,
WA
Project Cost
Treatment
NA
$72,000,000
NA
$1,900,000
NA
NA
Total
$133,000,000
$110,000,000
NA
$5,300,000
$8,100,000
$6,000,000
f\ A.* A.
Quantity
Incinerated
248,000 tons
of soil and
sediment
250,000 tons
of sediment
and waste pile
material
172,000 tons
of sediment,
sludge, debris,
oil, and soil
4,660 tons of
soil and
sludge
9,7 15 tons of
soil
7,840 tons of
soil*
Calculated
T T * A. /"""< A. £
Unit Cost for
Treatment**
NA
$288/ton
NA
$410/ton
NA
NA
Total
Unit Cost
$540/ton
$440/ton
NA
$l,000/ton
$830/ton
$770/ton
Comments
• No comments.
• EPA paid for the incineration on the basis
of dry weight of the ash instead of the
weight of the feed material. It therefore
was more desirable to the contractor to
optimize the process train and guard
against the unnecessary incineration of
moisture.
• SCC supports required rebuilding to repair
loss of structural integrity.
• Slag falling into ash quench caused damage
to ash and feed augers requiring numerous
repairs.
• The site operator believes on-site
incineration was uneconomical, compared
with off-site incineration because a
relatively small amount of waste was
treated.
• No comments.
• Statistical methodology used to minimize
the amount of soil excavated.
29
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Table 4. Summary of Cost Data for Each Site
(Page 2 of 3)
Site Name
MOTCO, TX
Old Midland,
AR
Petro
Processors,
LA
Rocky
Mountain
Arsenal, CO
Rose Disposal
Pit, MA
Project Cost
Treatment
$31,000,000
$22,500,000
(excavate,
incinerate,
backfill)
$4,800,000
(to date)
$58,100,000
NA
Total
$76,000,000
$27,000,000
$32,800,000
(to date)
$93,000,000
NA
f\ A.* A.
Quantity
Incinerated
23,021 tons of
soil, sludge,
organic liquid,
and aqueous
waste
102,000 tons
of soil, sludge,
and sediment
213,000
gallons of
organic liquid
and fumes (to
date)
10.9 million
gallons of
liquid
5 1,000 tons of
soil
Calculated
T T * A. /"""< A. £
Unit Cost for
Treatment**
$l,350/ton
$220/ton
(excavate,
incinerate,
backfill)
$21/gal
$5/gal
NA
Total
Unit Cost
$3,300/ton
$264/ton
$154/gal
$9/gal
NA
Comments
• Inaccurate initial characterization of the
waste stream resulted in many mechanical
problems during incineration operation.
• The criterion for dioxin and furans in ash
was raised from 0.1 to 1.0 ppb, reducing
residence time and increasing throughput.
• Amount of contaminated soil
underestimated.
• No comments.
• Heavy rainfall increased volume of liquid
requiring treatment. The construction of a
special holding pond was required,
increasing "before treatment" capital costs.
• Before treatment costs were $ 14,800,000;
after treatment costs were $18,900,000.
• Operating in the winter caused weather-
related difficulties, resulting in suspension
of the operation until spring.
30
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Table 4. Summary of Cost Data for Each Site
(Page 3 of 3)
Site Name
Rose
Township
Dump, MI
Sikes Disposal
Pits, TX
Times Beach,
MO
Vertac
Chemical
Corporation,
AR
Project Cost
Treatment
NA
$81,000,000
Confidential
NA
Total
$12,000,000
$115,000,000
(total includes
$11,000,000
in
miscellaneous
O&M costs)
$110,000,000
$31,700,000
f\ A.* A.
Quantity
Incinerated
34,000 tons of
soil, rocks,
and tree
stumps
496,000 tons
of soil and
debris
265,000 tons
of soil and
debris
9,804 tons
waste and soil
Calculated
T T * A. /"""< A. £
Unit Cost for
Treatment**
NA
$160/ton
Confidential
NA
Total
Unit Cost
$350/ton
$230/ton
$420/ton
$3,200/ton
Comments
• An estimated 600 tons of incinerator ash
required reincineration because it did not
meet criteria for on-site disposal.
• Completed 18 months ahead of schedule
because the contractor supplied a larger
incinerator.
• Before treatment costs were $20,000,000;
after treatment costs were $3,000,000.
• An estimated 1,900 tons of incinerator ash
required reincineration because it did not
meet criteria for backfilling.
• The mixed solid and liquid waste stream
had a variable Btu content, creating
difficulties in maintaining optimal
temperature in the kiln.
• Because of low pH of waste stream issues
related to worker health and safety arose.
• Residual ash was disposed of in a facility
permitted under RCRA Subtitle C, thereby
increasing disposal costs.
* Quantity reported as cubic yards. Tons were calculated by multiplying cubic yards by an average density value of 1.4.
* * Unit cost calculated when costs for treatment only were available; does not include costs for before-treatment or after-treatment.
31
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Table 5. Current and Proposed Incinerator Standards
Pollutant
Dioxins/furans
(ng TEQ/dscm)
Mercury (ug/dscm)
Total chlorine (HC1 and
C12) (ppmv)
Semivolatile metals
(lead, cadmium)
(ug/dscm)
Low volatility metals1
(antimony, arsenic,
beryllium, chromium)
(ug/dscm)
Particulate matter
(gr/dscf)
Carbon monoxide
(ppmv)
Total hydrocarbons
(ppmv)
RCRA Current
Standards Under
Parts 264/265
Subpart O
No Federal
emissions standard2
No Federal
emissions standard3
No greater than 4
Ib/hror l%HClin
stack gas prior to
entering any
pollution control
equipment
No Federal
emissions standard3
No Federal
emissions standard3
0.08
100
No Federal
emissions standard
April 16, 1996
Proposed MACT
Standards
0.2
50
280
270
210
0.03
100
12
May 2, 1997
Revised MACT
Standards
0.2
40
75
100
55
0.015
100
10
dscf:
dscm:
gr:
ppmv:
TEQ:
i"g:
ng:
Dry standard cubic feet
Dry standard cubic meters
Grains
Parts per million by volume
Toxic equivalents
Micrograms
Nanograms
EPA has determined that emissions on antimony may be adequately addressed by
meeting the particulate matter standard.
Dioxin/furan limits may be imposed based on results of site-specific risk
assessments under the RCRA omnibus authority (40 CFR 270.32(b)(2)).
RCRA permitting authority may be used to impose BIF metal limits (40 CFR
266.106) or limits based on site-specific risk assessment results (40 CFR
270.32(b)(2)).
32
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REFERENCES
1. Woodward-Clyde Consultants. Final Decision Document for the Interim Response Action Basin F
Liquid Treatment Rocky Mountain Arsenal. Volume 1. Text. May 1990.
2. Buonicore. A.J. and W. T. Davis, Air Pollution Engineering Manual. Air and Waste Management
Association. 1992.
3. U.S. Environmental Protection Agency (EPA). Combustion Emissions Technical Resource Document
(CETRED), Draft. EPA-530-R-94-014. May 1994.
4. EPA. Technical Support Document for FiWC MACT Standards, Volume 1: Description of Source
Categories. Draft. RCSP-S0047. February 1996.
5. Leite, O. Equipment for Incineration of Liquid Hazardous Wastes. Environmental Technology.
May/June 1996.
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