-------
TABLE 3.7
DISTRIBUTION OF WASTE CONTAMINANT ELEMENTS BETWEEN SLAG AND METAL
Group I - Elements almost completely taken up by slag: Si, Al, Ti, Zn, B,
V, Ca, and Mg
Group II - Elements distributed between slag and metal: Mn, P, S, and Cr
Group III - Elements almost completely in solution in metal: Cu, Ni, Sn, Mo,
Co, W, As, and Sb
Group IV - Elements out of slag and metal: Zn, Cd, Pb, Ag, and Hg
Source: Reference 23.
3-37
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and has becomes contaminated with water, organics, inorganics, etc. The acid
drops in strength and is no longer usable for its intended purpose. In a re-
covery furnace, the spent acid is thermally decomposed at elevated tempera-
tures into SC>2, carbon monoxide, carbon dioxide and water vapor. Heat needed
for the acid decomposition is supplied by burning fuels, typically natural gas,
oil or a liquid or gaseous waste stream. The SO2 generated in the recovery
furnace ranges from 0-14% of the exhaust gases.
The conversion of the S(>2 to sulfuric acid follows the contact process
as depicted in Figure 3.9. The SC>2 is oxidized to 803 in a multi-stage con-
verter, typically having either three or four stages depending on the age of
the plant and overall conversion efficiencies desired. The converting from
SC>2 to SO^ requires very controlled reaction temperatures for efficient con-
version. The exhaust gases from the combustion chamber are cooled by a waste
heat boiler prior to entering the converter. After passage through each stage
of the converter, the gases are cooled by waste heat boilers or super heaters
to maintain the desired temperature ranges. The stages of the converter each
have a bed of solid vanadium pentoxide catalyst. The conversion rate drops as
each stage of the converter has less SO2 than the previous stage. Gases leav-
ing the converter are again cooled and are introduced into the 803 absorber
at about 450°F. If oleum is to be produced, the temperature is lowered fur-
ther prior to entry into the oleum tower.
The 803 absorber is similar to the drying tower used for the combustion
air. The 803 is absorbed in sulfuric acid which is continuously drawn-off
as the product (Reference 26). The sulfur dioxide, sulfur trioxide and sul-
furic acid remaining in the exhaust gases must be reduced to meet air pollu-
tion standards.
Since the enactment of these strict air pollution regulations in 1971,
most new plants use a dual absorbtion process to lower the SO2 emissions.
The primary 303 absorber, known as the interpass absorber, is used as the
gases leaving the third stage of the converter (Reference 27). The lower
partial pressure of the 803 in the gases returning to the fourth stage in-
creases the conversion rate and thereby lowers SO2 emissions. The second
803 absorber is similar to the single absorber system but only absorbs 803
from the gases exiting the fourth stage of the converter.
Plants built prior to 1960, generally had three stage converters and
overall conversion efficiencies of 95-96% (Reference 27). In modern four
stage converter contact process plants the overall conversion efficiencies
approach 99%+.
If oleum is produced at the acid recovery plant, the 803 leaving the
converter is cooled further and is introduced to an absorption tower with
100% sulfuric acid.
The recovery furnace is usually a refractory lined cylindrical chamber
equipped with a burner designed to spray the spent acid into the chamber
without flame impingement on the walls. The design of these furnaces vary
according to plant production capacity, but can be 40 feet long by 14 feet
in diameter. The combustion air is sometimes dried before entry into the
burner in order to prevent corrosion (acid mist formation) of th«s process
equipment by the 803 combining with the water vapor to form sulfuric acid.
3-38
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OJ
bJ
10
[-SPENT A:ID
-SULFUR
-FUEL Oil.
WATER -
STEAM
PiJS
FURNACE OUST IMTEHEAT GAS GAS ELECTROSTATIC
COLLECTOR BOILER SCRUBBER COOLER PRECIPITATOnS
AIR
11
T
S02
STRIPPER
[ATMOSPHERE
HEAT EXCHANGERS CONVERTER
DRYING
TORER
ABSORPTION
ACID PUMP TANK COOLER
ACID COOLERS lit ACID PUMP TANK
FIGURE 3.9 CONTACT PROCESS 8ULFURIC ACID PLANT BURNING SPENT ACID
REFERENCE 26
-------
Since spent acid have contaminants such as water, organics and inorganics,
they have the potential to corrode and plug the converter beds and other
downstream equipment. It is reported that spent acid usually contains about
90% sulfuric acid, 4 to 5% water, and 5 to 6% hydrocarbons (Reference 28).
The gasss are cleaned and dried after the combustion/waste heat boiler by
cyclones, electrostatic precipitators, scrubbers- and/or gas cooling towers.
Combustion
The combustion of spent acid needs to be balanced to achieve the de-
sired range of 8-14% SO2 in the exhaust gases. This can be accomplished by
fuel blending and combustion air adjustments. It is important to note that
as the percentage of SO2 drops, more exhaust gases need to be processed to
create the same amount of acid (i.e., the plant exhaust gases with SO2 at 4%
in the combustion gases, will be 2.5 times that of SO2 at 10% in the combus-
tion gases) (Reference 27). Therefore, burning multiple fuels with/and with-
out significant oxygen contents, makes the efficient combustion system very
complex (Reference 29). The contro.1 of combustion relies on both tempera-
tures and oxygen controls.
Emission and Air Pollution Control
The exhaust gases from a spent acid recovery furnace are processed to
sulfuric acid before being emitted to the atmosphere. Therefore, furnace air
emissions are referenced to the tail and of the entire acid plant. The major
pollutants emitted from a spent acid plant are SO2 and sulfuric acid mist.
The quantity of SO-, emitted is an inverse function of the sulfur conversion
efficiency (SO oxidized to 803). This conversion i-3 always incomplete, and
is affected by the number of stages in the catalytic converter, the amount of
catalyst used, temperature and pressure, and the concentrations of the reac-
tants (SO2 and 02). Host single absorption plants have SO2 conversion effi-
ciencies ranging from 95-98%, which corresponds to 26 to 55 Ib SO3 emitted
per ton of 100% H2SO4 produced. The EPA performance standard for new plants
is 4 pounds SC>2 per ton of 100% H2SO4 produced which corresponds to a conver-
sion efficiency of approximately 99.7%.
Nearly all the acid mist emitted from the spent acid plant is in the ab-
sorber exist gases. Acid mist is created when SO3 combined with water vapor
at a temperature below the dew point of 503. Once formed within the process
system, this mist is so stable that only a small quantity can be removed in
the absorber. The water vapor is produced from the water in the spent acid
and products of combustion of the fuels and hydrocarbon impurif'.as in the
spent acid.- The strength of the acid produced also affects mist emissions.
Plant producing higher concentrations produce greater quantities of finer
more stable mist. Another greater quantities of finer more stable mist.
Another factor affecting the mist emissions is the operating temperature of
the SO3 absorption tower. The optimun absorber operating temperature depends
on the strength of the acid produced, throughout rates, inlet 803 concentra-
tions. Typically, uncontrolled mist emission from a spent acid plant are 2.2
- 2.4 Ib/ton acid produced (Reference 15). The EPA New Source Performance
Standard is 0.15 pound per ton of acid produce which requires the applica-
tion of control devices which are discussed later in this subsection.
3-40
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When the spent acid and fuels burned in the recovery furnace, particu-
lates, metal, and trace quantities of other pollutants may also be generated.
The mature of these pollutants will depend on the type of fuel burned and the
contaminants in the spent acid. Those polluants that might plug or deactivate
the converter catalyst must be removed before the furnace exhaust gases enter
the converter. Thus air pollution control equipments are used in spent acid
plants for pre-converter cleaning of the furnace exhaust gases (for particu-
late matter, metals, acid mist, etc.) and to the process exhaust gases prior
to their being released to the atmosphere.
The pre-converter control can be:
o Cyclones
o Scrubbers
o Electrostatic precipitators
o Dryers
The emission controls used to meet NSPS are:
o Sulfur dioxide control - dual absorption systems
- sodium sulfate to sodium bisulfate
scrubber
- ammonia scrubber
o Acid mist - electrostatic precipitator
- mist eliminators
- packed bed scrubbers
- molecular sieves
The pre-converter controls are well suited to remove particulate matter,
vaporized metals and hydrochloric acid emissions. All of these parameters
would have operational significance if allowed to contaminate or plug the
catalyst beds in the converter. While not all spent acid plants have all
of these control devices, they must have adequate controls to prevent the
expensive replacement of the catalyst.
Compatible Wastes
Hazardous waste burned in a spent acid recovery furnace as fuel must
not adversely affect the acid production process equipment nor significantly
alter the arid quality. The pre-converter cleaning devices can remove some
hazardous waste contaminants that are not destroyed during the combustion,
such as metals. However, because of the possibility that some portion of
metals reaching the converter, operations are lively to restrict the level
of metals in the waste fuel. They would also likely limit the amount of
chlorinated wastes burned as fuel to avoid potential conversion problems
in furnace and prevent adversely affecting the acid quality.
3-41
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A3PHALT CONCRETE PLANTS
General
The bituminous concrete industry composes some 3,000-4,500 plants (Refer-
ences 30 and 31 ) r-.-ross the United States. Their locations follow the general
population and number of motor vehicles patterns since their product is used
in population/vehicular flated ways (i.e., roads, parking lots, driveways).
Approximately 60% are stationry, 20% are mobile and 20% are somewhat trans-
portable (Reference 30).
Bituminous concrete is a blended mixture of asphaltic cement (AC) and
aggregate. The variations of the types of mixes are numerous with different
asphaltic cement blends and different size and material combinations, of ag-
gregates (i.e., sand, rock, glass, asbestos, reprocessed asphalt pavement).
The oasic asphalt concrete manufacturing process is composed of:
o Heating of the aggregate to drive off moisture and to facilitate
mixture with the AC.
o Screening of the aggregate.
o Blending the aggregate with heated AC and mixing for a homogeneous
product.
The actual plant designs are grouped into three subsets:
1. Batch-mix plants - separates the heating, screening, and blending
production steps. Mixes one batch at a time; rotary dryer is
started and stopped many times during the day. Represents 91%
(Reference 30) of reported population.
2. Drum-mix plants - sizes the aggregate first, then combines the
heating and blending steps. Usually runs for longer periods than
a batch plant. Represents 2.5% (Reference 30) of the reported
population but is the majority of all new plants.
3. Continuous-mix plants - similar to a batch-mix design but runs con-
tinuously for long periods based on constant demand. Represents
6.5% (Reference 30) of the reported population.
Process Description
For the context of burning HWDF's, the three subsets can be looked at
as two groups; rotary dryer heating of the aggregate only (typical batch-
mix plant) and rotary dryer heating and mixing the aggregate and AC (typical
drum-mix plant). The continuous-mix design has the same combustion charac-
teristics as the batch-mix desig:.
Figure 3.10 shows the schematic of a typical batch-mix plant. Agc,jegates
are stored in outside piles of graded stone, sand, etc. The aggregates are
fed into hoppers and then proportioned based on mix design, onto a conveyor
belt to be fed into the rotary dryer. The aggregate is heated to about 300-
350°F depending on mix requirements and then moved by a hot elevator to the
screens for final sizing. The screens discharge into the pug mill where the
hot aggregate is blended/mixed with the hot AC. After mixing the batch is
3-42
-------
EXHAUST TO
ATMOSPHERE
PRIMARY OUST
COLLECTOR
-J
COARSE
AGGREGATE
STORAGE
PILE
FINE
AGGREGATE
LOADER! STORAGE
PILE
i
£.
Ul
BINS
FEEDERS—£i S—-
CONVEYOR^-*
AC INJECTION
TORAGE
^p QA8 FLOW
FIGURE 3.10 TYPICAL BATCH-MIX ASPHALT CONCRETE PLANT
REFERENCE 33
-------
dropped into a dump truck for transporting to the job. Typically, several
batches are required to fill a waiting truck and the system (i.e., conveyor,
dryer, screens, pug :nill) only operates on a per truck basis. Recent tech-
niques have been applied to this operation that allow:
o If the requirement for a certain mix is large (roadway paving/resur-
facing), a heated storage silo is used to run the system for longer
intervals and still allow for making other batch mixes.
o Recycling of old asphalt pavement (RAP) is performed for economics
of the roadway project and plant operations, as well as, reducing
resurfacing pavement height and total pavement weight. The previous
layer of asphalt concrete is removed and taken to the plant. It is
crushed and sized as regular aggregate but stored separately. It
is usually heated in an auxiliary dryer by the hot exhaust gases of
the rotary dryer and combined with the hot aggregate for mixing with
the AC in the pug mill.
The rotary dryers are designed to quickly heat the rock and drive off
most of its surface and pore moisture that would interfere with the proper
bonding with the AC.
The fuel being combusted (gas, oil, waste oil, HWDF) in the burner, is
converted into heat and exhaust gases. Outside the actual flame, the gases
contact the cold stone and quickly drop in temperature to about 350"F or less.
The desired flame pattern is short and wide but without impingement on the
sides of the dryer.
The typical drum-mix plant is shown in Figure 3.11. The aggregate is
taken from the storage piles and is metered to the conveyor system for speci-
fic mix requirements. In die rotary dr^er, the AC is sprayed onto the aggre-
gate just outside of the flame zone (ther-a are several variations to this AC
injection method). The aggregate's moisture is driven off and the AC and ag-
gregate are mixed by the rotating action of the drum dryer. No hot screens,
hot elevators or pug mill are needed with the drum-mix plant. Due to its
design of mixing in the dryer, efficient operation dictates more continuous
production. Therefore, sto: i~ge silos for the asphalt concrete are typically
found at all drum-mix plants. Also, when RAP is used at these plants, it is
introduced into the drum after the flame zone.
The drying/mixing zone of the drum-mix dryer, is similar to the dryer
of a batch-mix plant but modified to prevent flame impingement on the AC.
The exhaust gas temperatures of a drum-mix plant can be slightly higher than
a batch-mix plant as are the temperatures of the asphalt concrete, to compen-
sate for additional heat loss in storage.
Combustion
The combustion zones in both the batch-mix and drum-mix dryers are simi-
lar. The flame is short and releases sufficient heat to raise the aggregate
to approximately 300°F. The burners use sufficient excess air to ensure
proper combustion of the fuel and the desired aggregate temperature. Resi-
dence time at combustion conditions (>1,500°F) is short since the wet aggre-
gate cools the exhaust gases very quickly. The burners operate efficiently
3-44
-------
U<
AQQnF.QAIE
AND SAND FEED
POMI
AQOHEQAIE
AND 8ANO FEED BINS
CON VE von
FIGURE 3.11 TYPICAL DRUM-MIX ASPHALT CONCRETE PLANT
REFERENCE 33
-------
for their normal fuels and have the potential to adequately combust some haz-
ardous waste derived fuels.
Emissions and Air Pollution Controls
The New Source Performance Standards (NSPS) (Reference 32) for asphalt
concrete plants are as follows:
1. Particulate emissions - <_ 0.04 gr/dscf
2. Opacity - £ 20%
The standards apply to those planes constructed or modified as of June
'1, 1973 (estimated to be 15% (Reference 30) of all asphalt concrete plants).
The compliance with the NSPS particulate emission standards typically
requires the use of:
o Baghouaes
o High energy scrubbers
The typical batch-mix plant can meet the NSPS standards by use of bag-
house or scrubber, however, due to energy requirements, baghouses predominate
(Reference 30).
The typical drum-mix plant uses a scrubber or baghouse (Reference 30)
but the use of scrubbers is prevalent due to the potential blinding of bag-
house filters with condensed hydrocarbons from the AC. It has been reported
(Reference 33) that some drum-mix plants do not utilize any controls due to
the inherent particulate control of the AC as it forms a collection surface
for particles generated from the aggregate. However, the AC and the heat in
the drum produces a hydrocarbon emission, that condenses and cause condensi-
ble particulate emissions and plume opacity (Reference 30).
Plants built prior to 1973 are principally the batch-mix or continuous-
mix design and use air pollution controls such as:
o Cyclones
o Low energy scrubbers
The typical emission regulations for these older plants are process
weight related and allow partial late emissions an order of magnitude greater
than NSPS. The typical process weight derived allowable particulate emission
rate for a 100 ton/hour plant is 30 Ibs/hour (approximately 0.1 gr/dscf).
Since asphalt concrete plants can burn various types of fuel and not
affect product quality, they have been users of waste oils and other blended
wast4 derived fuels. A 1985 study (Reference 34) reports that about 80% of
all the purchased waste oil derived fuel in California were burned in 1984
by industries in the Standard Industrial Code 2951 - Paving Mixtures and
Blocks. The majority of this code index group are asphalt concrete plants.
3-46
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Compatible Wastes
Most asphalt dryers could easily be adapted to fire a liquid hazardous
waste since most are oil - or combination gas anc oi_ - rired units. The
major compatibility problem would likely be- the potential equipment corrosion
assoicated with firing highly halogenated wastes. Halogen composition speci-
fications would be required to protect the dryer and associated air pollution
control equipment.
Little adverse impact on product quality is anticipated from firing haz-
ardous waste. Organic compounds would likely be destroyed (see test results
below) sufficiently by the combustion process that they would not significant-
ly alter the product composition and quality. Metals entering the aggregate
from the firing of hazardous waste will be insignificant, with a few excep-
tions, compared to the levels naturally occuring in the aggregate as dis-
cussed in the test results oresented below.
CHARACTERIZATION OF FURNACES FOR DISPERSION MODELING
The following descriptions of furnaces, which later will be used for
dispersion modeling, were assembled from data taken from a number of sources
and are intended to be representative of the industry recognizing that the
selected plants may not exist anywhere. They are intended to provide a basis
for analysis of the environmental impacts of burning hazardous wastes on spe-
cific segments of the industry. The emission and stack data were used in
atmospheric dispersion models for the risk assessment and the cost analyses.
Only the furnace facilities are described; the remainder of the plant facil-
ities are not affected by burning hazardous waste except in a very limited
manner (i.e., coal mills might operate less and result in lower maintenance
and operating costs). For selection of the lime kiln and the lightweight
aggregate kiln, this analysis utilized the same facilities used by EPA in
its NSPS analysis. The other furnaces were selected to be representative
of the industry.
Wet Process Cement Kiln
The typical wet kiln has a production capacity of 850 TPD for an annual
production of 266,500 tons. Primary fuel for the kiln is coal, required in
the amount equivalent to 5.5 x 10^ Btu/ton. Using a heating value of 12,500
Btu/pound, 7% ash, and 1.7% sulfur on an as-fired basis, the kiln will burn
7.5 tons/hour of pulverized coal. The kiln itself is 500 feet long, 11.5
feet in diameter, and rotates at 90 revolutions per hour (rph). Solid resi-
dence time is 2 to 2.5 hours.
The exhaust gases from the kiln contain 25% (by volume) water vapor, 29%
CO2, 455 ppm SO2, 265 ppm NOX, and 100 ppm CO. The gas discharges at 520°F
into a multiclone at the rate of 150,300 acfm (60,720 dscfm). Following the
multiclone is a 4-field, 2-chamber ESP which ramoves 98.4% of inlet dust load-
ing and the stack discharges 137,700 acfm at 438°F (60,720 dscfm). Table 3.8
summarizes the kiln stack emission parameters used for the health effects
modeling.
3-47
-------
TABLE 3.8
EMISSION CHARACTERISTICS OF A REPRESENTATIVE
WET PROCESS CEMENT KILN
Parameters
Values
Stack Height
Stack Diameter
Stack Gas b'low Rate
Stack Gas Temperature
Emission Rates
Particulate Matter
Sulfur Dioxide
Nitrogen Oxides
Carbon Monoxide
170 feet
11 feet
137,700 acfm
60,720 dscfm
4388F
0.11 gr/acf
455 ppm
265 ppm
100 ppm
130 Ibs/hour
365 Ibs/hour
93 Ibs/hour
35 Ibs/hour
3-48
-------
Dry Process Cement Kiln
The configuration for the model dry process kiln is selected both to re-
present a stack/control device system different from the wet process plant
and to approximate a typical dry process; a 4-stage suspension preheater and
a rotary kiln 9 feet in diameter and 30C feet long. Capacity of the kiln is
394,000 TPY or 1,270 TPD of clinker. As with the we', process kiln, primary
fuel is coal which is fed to the kiln at 6.4 tons per hour based on a heat
requirement of 3 x 10^ Btu/ton clinker aud coal heating value of 12,500 Btu/
Ib, 7% ash, and 1.7* sulfur.
The kiln exhausts 154,900 acfm (104,COO dscfm) of gas at 320°F to a
eyelone/fabric filter particle removal system. The control system removes
99.8% of the total dust load and discharges 15 Ibs/hour of particulate mat-
ter through a 9-foot diameter stack at 120 feet above the ground. These
data and other emission information are summarized in Table 3.9.
Lime Kiln
Basically, the model kiln presented here is the same configuration used
by EPA in its analysis of the lime industry for the NSPS. The industry has
not changed significantly in teras of size of technology since that review
in 1977 (Reference 17).
The model lime kiln has a capacity to produce 500 TPD of quick lime from
1,000 TPD of limestone. Fuel is 3% sulfur coal with a heating value of 12,500
Btu/lb, and for a requirement of 7 x 106 Btu/ton of lime, is burned at a rate
of 140 TPD. Dust loss from the kiln is considered to be 10% of the kiln feed
rate or 8,300 Ibs/hour.
The kiln exhausts this dust in 41,000 dscfm of flue gas at a temperature
of 700°F with 14% (volume) water vapor. The gas contains a maximum of 1500
ppm sulfur oxides, about 150 ppm NOX, and less than 50 ppm CO.
Particulate matter removal is provided by fabric filter which exhausts
300°F gas to the atmosphere through a short 3-foot diameter stack on top of
the baghouse. Discharge elevation is 80 feet (Table 3.10).
Lightweight Aggregate
The model lightweight aggregate kiln presented here is the same as that
used by EPA in its analysis of the lightweight aggregate industry for NSPS
(Reference 21). This kiln has a production capacity of 1000 cubic yards per
day (840 tons/day). It is fueled by pulverized coal at a rate of 157.5 tons/
day for an assumed heat requirement of 4.5 x 106 Btu/ton of aggregate. The
coal has a heating value of 12,000 Btu/lb and a sulfur content of 4%.
The model kiln has the following emission characteristics. Uncontrolled
particulate emissions from this kiln are 842 Ibs/hour. A wet scrubber is used
to reduce these emissions by 99% to 8.42 Ibs/hour. Uncontrolled S02 emissions
are 238 Ibs/hour. There is essentially no removal of SO2 by the wet scrubber.
3-49
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TABLE 3.9
EMISSION CHARACTERISTICS OF A REPRESENTATIVE
DRY PROCESS CEMENT KILN
Parameters
Values
Stack Height
Stack Diameter
Stack Gas Flow Rate
Stack Gas Temperature
Emission Rates
Farticulate Matter
Sulfur Dioxide
Nitrogen Oxide
Carbon Monoxide
120 feet
9 feet
154,900 acfm
104,000 dscfm
320°P
0.011 gr/acf
520 ppm
310 ppm
100 ppm
15 Ibs/hour
540 Ibs/hour
140 Ibs/hour
45 Ibs/hour
3-50
-------
TABLE 3.10
EMISSION CHARACTERISTICS OF A REPRESENTATIVE LIME KILN
Parameters
Values
Stack Height
Stack Diameter
Stack Gas Flow Rate
Stack Gas Temperature
Emission Rates
Particulate Hatter
Sulfur Dioxide
Nitrogen Oxides
Carbon Monoxide
30 feet
3 feet
67,000 acfm
41,000 dscfm
300°F
0.073 gr/acf
1500 ppm
150 ppm
50 ppm
42 Ibs/hour
615 Ibs/hour
44 Ibs/hour
9 Ibs/hour
3-51
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The exhaust gas from the scrubber is vented to the atmosphere through a
105-foot, stack that has a 4-foot inside diameter at the exit. This gas leaves
the stack at 160°F and a flow rate of 49,980 scfm (Table 3.11).
Blast Furnace
The model blast furnace selected for this study is 102 feet tall with
a hearth diameter of 27 feet and normally produces 3,000 tons of molten iron
per day. The coke rate used is 900 pounds per ton of hot metal. This is
supplemented by 150 pounds of fuel oil per ton of hot metal. Liquid hazard-
ous waste may be substituted for the fuel oil in any proportion for purposes
of the regulatory impact analysis. Hot blast air is provided at the rate
of 86,000 standard cubic feet per minute and at a hot blast temperature of
2,000°F. During the production, 100,000 standard cubic feet per minute of
off-gases are generated.
The off-gases from the furnace contains 25.4% carbon monoxide, 12.5%
carbon dioxide, 3.5% hydrogen, on a dry volume basis. Moisture is 1.45% on
a volume basis. These gases leave the blast furnace and pass through a dust
removal system consisting of mechanical collectors followed by a venturi
scrubber. The gases leaving the cleaning system has dust concentration of
0.01 grains per cubic feet.
Forty-one percent of the blast furnace off-gases are used to fire the
blast air stove with the remainder being used to fire a boiler. Assuming
that 15% excess air is used in combusting the 100,000 scfm of off-gases,
160,000 scfm of combustion products would be generated; 65,600 scfm in the
blast air stoves and 94,400 scfm in the boiler. The 65,600 scfm of combus-
tion products generated in the stoves are exhausted to the atmosphere at
an average temperature of 500°F through a 200 foot stack that is 4 feet in
diameter. The boiler combustion products (94,400 scfm) will exit through
a 100-foot stack at 350°F. This stack is 10 feet in diameter.
Open Hea rth^ Furnace
The model open hearth furnace selected for this study has a capacity of
320 tons of steel per heat with a tap-to-tap time of 8 hours. Thus, it can
produce 960 tons of steel per day. It is fueled by natural gas and oil in
approximately equal quantities on a heating value basis. The heat require-
ment for steel production in the furnace is '3.5 x 106 Btu per ton of steel
produced.
The model furnace has the following emission characteristics. Uncon-
trolled emissions from the furnace is 16 pounds per ton steel produced or
640 pounds per hour. An electrostatic precipitator is used to reduce these
emissions by 98% to 12.8 pounds per hour (0.02 gr/dscf).
The exhaust gas from the electrostatic precipitator is vented through
a 150 foot stack that has an 8-foot inside diameter at the exit. This gas
leaves the stack at 400°F and a flow rate of 65,000 standard cubic feet per
minute.
3-52
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TABLE 3.11
EMISSION CHARACTERISTICS OF A REPRESENTATIVE
LIGHTWEIGHT AGGREGATE KILX
Parameters
Values
Stack Height
Stack Diameter
Stack Gas Flow Rate
Stack Gas Temperature
Emission Rates
Particulate Matter
Sulfur Dioxide
Nitrogen Oxides
Carbon Monoxide
105 feet
4 feet
67,200 acfm
49,980 dscfm
160°F
0.015 gr/acf
475 ppm
150 ppm
50 ppm
8.4 Ibs/hour
238 Ibs/hour
54 Ibs/hour
11 Ibs/hour
3-53
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Spent Acid Recovery Furnu".e
The model spent acid recovery plant has been developed with the follow-
ing characteristics:
o Production Rate-.
o Fuels:
o Exhaust Temperature:
o Exhaust Flow:
o Stack Height:
o Stack Diameter:
o Air Pollution Controls:
o Emission Rate:
Asphalt Aggregate Kiln
720 tons/day of sulfuric acid
252 tons/day sulfur total
84 tons/day elemental sulfur
126 tons/day spent acid
16,800 tons/day HWDF with 50% S and 50%
organics
90°F
20,000 scfm
75 feet
4 feet
packed tower
dual absorption system
.08 gr/dscf particulates at 7% oxygen
4 Ibs/hr HCX
99.99% ORE
The model asphalt concrete plant selected for the engineering cost anal-
ysis and the risk assessment is as follows:
o Plant Type:
o Production Rate:
o Fuel:
c Operational Rate:
o Stack Characteristics
Temperature:
Flow rate:
Moisture content:
Diameter:
Height:
o Air Pollution Control:
batch-mix plant
200 tons per hour
300 gallons per hour of fuel oil or
waste derived fuel
5 hours per day
5 days per week
40 weeks oer year
150'F
20,000 >ofm
25%
4 feet
25 feet
low energy scrubber (spray bars, damper,
wet fan)
3-54
-------
o Emission Rates: .08 gr/dscf particulates at
7% oxygen
4 to 30 Ibs/hr HC1
99.99% ORE
3-55
-------
REFERENCES
1. Shreve, R.N. Cheniical Process Industries. McGraw-Hill, 1962.
2, Addendum to the Draft Final Report: Source Category Survey of the Clay
and Fly Ash Sintering Industry. Prepared by Midwest Research Institute
for the U.S. Environmental Protection Agency. Contract No. 68-02-3059.
Draft Report. April 17, 1980.
3. Perry, R.H. and Chiiton, C.H. Chemical Engineers Handbook. Fifth Edi-
tion, McGraw-Hill, 1977.
4. Hazelwood, D.L. and Smith, F.J. Assessment of Waste Fuel Use in Cement
Kilns. Prepared by A.T. Kearney, Inc., for the U.S. Environmental Pro-
tection Agency. Draft Report. March 1981.
5. Feasibility of Using Lime Kilns to Burn Hazardous Wastes. Prepared by
A.T. Kearney, Inc., for the U.S. Environmental Protection Agency. Draft
Report. February 1981.
6. Standards Support and Environmental Impact Statement Volume I: Proposed
Standards of Performance for Lime Manufacturing Plants. U.S. Environ-
mental Protection Agency, Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina. EPA-450/2-77-007a. April 19V7.
7. Personal Communication Between Harry Robinson of the Expanded Shale,
Clay, and Slate Institute and Robert Patrick of Engineering-Sconce.
August 13, 1984.
8. Source Category Survey of the Clay and Fly Ash Sintering Industry. Pre-
pared by Midwest Research Institute for the U.S. Environmental Protection
Agency. Contract No. 68-02-3059. Draft Final Report. January 30, 1984.
9. Bieser, C.O. Identification and Classification of Combustion Source
Equipment. Prepared by the Process Research, Inc., for the U.S. Envi-
ronmental Protection Agency. EPA-R2-73-174. February 1973.
10. Jablin, R., et al. Pollution Effects of Abnormal operations in Iron and
Steelmaking - Volume III. Blast Furnace Ironmaking, Manual of Practice.
Prepared by Research Triangle Institute for U.S. Environmental Protection
Agency. Publication EPA-600/2-78-118c. June 1978.
11. Blast Furnace - Theory and Practice. Volume T.. Strassburger, J.H., et
al., editors. Gordon and Breach Science Publishers. New York. 1969.
12. Directory of Iron and Steel Works of the United States and Canada. Pub-
lished by the American Iron and Steel Institute. Washington, D.C. 1984.
13. Greenberg, J. Industrial Furnaces, Ovens, Kilns, Dryers, Boilers, Incin-
erators. Seminar Presented by A.T. Kearney, Inc. to the U.S. Environ-
mental Protection Agency, Cincinnati, Ohio. February 26, 1981.
3-56
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14. Campbell, R.L. Campbell & Pryor Associates Inc. Letter to M. Benoit,
Cadence Chemical Resources, Michigan City, Indiana, June 2, 1986.
15. Compilation of Air Pollutant Emission Factors. U.S. Environmental Pro-
tection Agency. Publication Ho. AP-42. April 1981.
16. Katari, V.S. and Gerstle, R.w. Industrial Process Profiles for Envi-
ronmental Use: Chapter 24. The Iron and Steel Industry. Prepared by
Radian Corporation for the U.S. Environmental Protection Agency. Pub-
lication EPA-600/2-77-023x. February 1977.
17. Kirk-Othmer Encyclopedia of Chemical Technology. 3rd Ed., Volume 13.
John Wiley & Sons, Inc. New York, New York. 1981.
18. Trinks, W. and Mawhinney, M.H. Industrial Furnaces, Volume II. John
Wiley & Sons, Inc. New York. 1967.
19. 1983 Annual Statistical Report. Published by the American Iron and
Steel Institute. Washington, D.C. 1983.
20. Pollution Effects of Abnormal Operations in Iron and Steelmaking - Vol-
ume IV. Open Hearth Furnace, Manual of Practice. Prepared by Research
Triangle Institute for the U.S. Environmental Protection Agency. Publi-
cation EPA-600/2-78-118d. June 1978.
21. Destruction & Removal of POHCs in Iron Making Blast Furnaces. Prepared
by Radian Corporation for the U.S. Environmental Protection Agency.
December 31, 1985.
22. Atmospheric Emissions from Sulfuric Acid Manufacturing Processes. U.S.
Department of Health, Education and Welfare. Division of Air Pollution,
Cincinnati, Ohio. 1965.
23. Hall, F.D., et al. Evaluation of the Feasibility of Incinerating Hazard-
ous Waste in High Temperature Indust^ia. Processes. Prepared by PEDCo
Environmental, Inc., for the U.S. Envirorunental Protection Agency. Pub-
lication PB 84-159391. February 1984.
24. Danielson, J. Air Pollution Engineering Manual. U.S. Environmental
Protection Agency. Publication AP-40. May 1973.
25. Vandergrift, A.E., et al. Particulate Pollutant System Study, Volume
III. Prepared by Midwest Research Institute for the U.S. Environmental
Protection Agency. May 1971.
26. New Source Performance Standards; Inspection Manual for Enforcement of
Sulfuric Acid Plants. U.S. Environmental Protection Agency. Office of
Enforcement, Washington, D.C. 1977.
27. A Review of Standards of Performance for New Stationary Source-Sulfuric
Acid Plants. U.S. Environmental Protection Agency. Office of Air Qual-
ity Planning and Standards, Research Triangle Park, North Carolina. 1979.
3-57
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28. Industrial Process Profiles for Environmental Use: Chapter 23. Sulfur
Oxides and Sulfuric Acid. U.S. Environmental Protection Agency. Office
of Research and Development, Cincinnati, Ohio. 1977.
29. Shafer, J.R., and Bo<;adi, J.S. Producing Sulfuric Acid in Refineries.
Chemical Engineering Practices, V.76, October, 1980. pp. 70-75.
30. A Review of Standards of Performance for New Stationary Sources, Asphalt
Concrete Plants. U.S. Environmental Protection Agency. Office of Air
Quality Planning and Standards. Research Triangle Park, North Carolina.
1979.
31. NEDS Source Classification Codes, February 1985 - Population and Through-
put Listing. U.S. Environmental Protection Agency. Office of Air yual-
ity Planning and Standards. Research Triangle Park, North Carolina.
1985.
32. Title 40, Code of Federal Regulations, Part 60, Subpart I - Standards of
Performance for Asphalt Concrete Plants.
33. Control Technology Evaluation of the Drum-^tix Process for Asphalt Con-
crete Manufacturing. U.S. Environmental Protection Agency. Environmen-
tal Research Information Center. Cincinnati, Ohio. 1978.
34. Assessment of Used Solvent and Used Oil as Fuel in California. Califor-
nia Air Resources Board. January 1985.
35. U.S. and Canadian Portland Cement Industry: Plant Information Summary.
Portland Cement Association. May 1983.
3-58
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SECTION 4
DESTRUCTION AND REMOVAL EFFICIENCY OF
HAZARDOUS MATERIALS BY INDUSTRIAL FURNACES
The EPA Office of Solid Waste (OSW) recognized the need to collect emis-
sion data from industrial furnaces burning hazardous wastes as fuels to sup-
port its regulatory efforts. EPA therefore developed a program to tesf. in-
dustrial furnaces burning a variety of waste streams. This section describes
the analytical methods used to test stack gases from furnaces burning hazard-
ous wastes, identifies those testing procedures that are or should be stan-
dardized for collecting test burn data, evaluates the QA/QC activities that
are or should be required for each method and identifies the quality accept-
ance criteria that were applied to test burn data collected from seven kilns,
three asphalt aggregate kilns, and a blast furnace.
Results from eleven trial burns (ten EPA and one California Air Resources
Board test) were analyzed to determine if the destruction of hazardous mate-
rials was adequate to protect the environment. Included in the analyses and
discussion are: the DRE, the POHCs, emissions of particles, emissions of HC1,
PICs, metals emissions, and combustion gases.
The last portion of Section 4 describes the types of system modifications
that would be required of existing production furnaces to enable them to safe-
ly burn hazardous wastes as fuels. Major facility modifications could include:
o Installing waste storage and handling facilities
o Installing laboratory testing facilities
o Installing waste pretreatment facilities
o Modifying or adding burner equipment
o Modifying or adding combustion controls
o Installing monitors for waste feed rate and stack gases (CO and 02)
o Modifying or adding air pollution control equipment
EVALUATION OF TEST METHODS FOR MEASURING ORGANIC EMISSIONS FROM COMBUSTION
SOURCES
The most widely employed procedures for measurement of the rates of emis-
sions of organic substances from combustion sources are the Modified Method 5
(MMS), the volatile organic sampling train (VOST) procedures, and EPA Method
23. The first two methods are conceptually similar; both sampling trains con-
sist of a particle filter, a condenser, a bed of porous polymer sorbent, and
a condensate trap. Their differences lie in their size, sorbent, and analyti-
cal techniques. Some of the salient attributes of the two methods are compared
4-1
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in Table 4.1. Method 23 specifies that stack gas samples be drawn into inert
plastic bags at a constant rate by a lung-type sampler. Analyses are usually
done in the field by GC with either flame ionization or electron capture de-
tection. The strengths and weaknesses of these test methods are discussed in
this section.
Modified Method 5 (MM5)
This method is an adaptation of EPA Method 5 (40 CFR Part 60) modified
to obtain samples for organic compound analysis as well as quantification of
particulate matter emissions. The adaptation (Figure 4.1) is the addition of
a sample gas condenser and a sorbent resin module between the heated filter
and first impinger of Method 5 train. The sorkxent resin moat commonly used
for hazardous waste combustion evaluation is XAO-2 which is highly effective
at trapping organic compounds with boiling points greater than 100°C (some-
times referred to as semi-volatile organic compounds or S-VOC).
The sample is collected by isokinetically drawing stack gas through a
heated glass or quartz probe, through a heated glass fiber particle filter
and then to the condenser/resin module. The sample gas is kept above 120°C
until it reaches the condenser where it is cooled to <20°C. Filtration tem-
peratures up to 150°C are used to minimize organic species condensation prior
to the condenser if this does not interfere with the determination of particu-
late matter. The sample gas and condensate pass through a resin bed located
below the condenser allowing the condensate to percolate through the bed and
collect in an impinger or condensate trap underneath the resin module. The
sample gas is then bubbled through two more impingers in the conventional
Method 5 configuration for acid gas and additional moisture removal.
Samples are analyzed by performing solvent extractions on the probe and
filter material as one fraction, the resin as a second fraction, and option-
ally on the condensate and impinger catches as third and fourth fractions.
The solvent extracts are concentrated and may be combined and analyzed by gas
chromatography (GC) using mass spectrometers (MS), flame ionization detectors
(FID), or electron capture detectors (ECO), as appropriate, for the organic
compounds of interest.
MM5 Procedure Standardization
The construction and operation of a Method 5 train is well known and well
described in the literature. The train operation, sample recovery, choice of
sorbent resin, and analytical method to be used in a given application of MM5
are not specified. At this time, a single description of how the MM5 train
is or may be used is not available. The sample collection aspects including
resin choice, are discussed in various publications, but the sample recovery,
analysis, and data reduction are not well described.
The Method 5 train and sample collection scheme has become the standard
for measurement of emissions of particulate matter and it is not surprising
that modifications to it have evolved in attempts to quantify other types of
emissions using the same equipment and techniques. Method 5 is written as a
test procedure for determining compliance with New Source Performance Stan-
dards (NSPS). This specificity has not been established for the MM5 proce-
dure as applied to hazardous waste ORE sampling in part because at least some
4-2
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TABLE 4.1
COMPARISON OF MM5 AND VOST PROCEDURES
Feature
MM5
VOST
Sampling Rate
Sorbent
Analysis of Condensate
Sample Recovery Technique
Analysis
Boiling Point of Analytes
Sampling Duration
1 4-40 1pm
XAD-2
Yes
Solvent Extraction
GC or GC/MS
>100°C
1 to 4 hours
0.5 to 1 1pm
Tenax*-GC
No
Thermal Desorption
GC/MS
30° to 100°C
0.3 to 1 hours
4-3
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Teui|i«f«|ii(f Senior . | | Stuck Wall
I'rolw "~~^
Type I'liut lul>«
lllOlinqinclor
Clirck V.lvt
Pilot Manomaler
necltciilallon Piiinp
Thciinoineloit
lm|t(ng
-------
of the measurement objectives will be different from test to test. Many of
the objectives will be the same and these need to be identified and the method
written to unsure that the goals are clear.
First, the relative priorities of ,ne«suring particulate n.atter vind or-
ganic compound emissions need <•<•» be sec. Most often these will not conflict
and no sacrifice of one measvireuent for another is needed. In the caatis
where sorae relatively significant quantity of organic chemical of interest
may be found :.n the "front half" (pvobe, filter, connecting glassware) of
che Method 5 train then the accuracy of particulate matter mecisurement may
need to be sacrificed to obtain the S-VX. Examples are net brushing the
probe to avoid contamination, renoving some particular matter with the
solvent used for S-VOC recovery, and/o-r operating the heated portion of the
train at higher than noraial tenperature (e.g., 205°C) and vaporizing parti-
culate matter which would otherwise deposit in the front t'aLf of the train.
In the case of o^l-firad boilers, much of the particulate matter is carbona-
ceous with little inorganic ash and the material contains straight chain and
aromatic hydrocarbons which may or may not be collected in the front half de-
pending on the filtration temperature. This is different from a coal-fired
unit where the ash is mostly (typically >95%) inorganic matter. If PCHCs or
PICs to be measured from hazardous waste combustion are to include naphthenic
or paraffinic hydrocarbons, then v/hether the boiler is oil- or coal-fired
will probably affect the sampling and analysis scheme.
What compounds are selected, as POHCs and P'.Cs also bears on the choice
of a suitable sorbent resin. Generally, the MM 5 is used to sample for PICs
- the higher boiling compounds, but it is als'j used to collect samples for
certain Appendix VIII compounds, e.g., toluene, monochlorobenzene. XAD-2
is the resin most commonly us-id and recommended as a general purpose sorbent
whea solvent extraction is the means of sample recovery. XAD-2 was selected
for its sorbert properties, ease of cleaning, and sample recovery efficiency.
Others are also used, for example, Tenax^-GC, if thermal desorption is the
sample recovery procedure. However, selection of a sorbent resin usually
involves a great deal of time and effort (literature and laboratory research)
tnat is usually not practical on a case-by-case basis.
last major uncertainty in regard to applying the MM5 DRE testing is
analyses - compound identification and quantification. Currently, GC is used
with one of three detection modes MS, ECO, and FID. Each has its own benefit?
and disadvantages relating to sensitivity, reproducibility, compound identi-
fication, interference rejection, and analytical cost. Each of these factors
needs to be considered and the method written to describe when each would be
appropriate.
MM5 QA/QC Evaluation
Most of the QA emphasis has been on obtaining acceptable blank values and
preventing contamination. The large gas volume and relatively large quantity
of resin concentrates the sample, which in conjunction with the solvent ex-
traction, usually results in a greater analyzable mass than methods employing
a lower sample volume. This greater analytical mass ten^s to decrease the
importance of trace contamination of the sample. The resin cleaning, blank
extraction, field trip, and laboratory handling blanks are adequate to iden-
tify problems and likely causes •
4-5
-------
There is one important aspect lacking in the method as it is being used
and this is use of field spikes to check on sample loss and recovery effi-
ciency. As currently practiced, the procedure does not provide a means for
determining t?~get compound collection efficiency or for evaluating sample
recovery. The nature of the sample and the field conditicns preclude the
usual option.of splitting the collected sample and spiking one split wich
a target compound to check loss and recovery. These spikfjs and replicate
analyses can be performed in the lab using the extractate with some loss of
sensitivity. It is also possible, and it seems highly advisable, to spike
the field samples with a tracer compound having properties similar to the
target compounds.
Because the volume of gas sampled by MM5 is large, the total quantities
of the various S-VOCs in the samples ranged from a few to several hundred
micrograms. Thus, the MM5 results are not greatly influenced by even a few
hundred nanograms of contaminants.
Two QA acceptance criteria were applied to the MM5 data before they were
included in this document.
1. The recovery of surrogate or spike compounds added to the sample be-
fore analysis must have been in the range of 50 to 150%.
2. The rate•of feed of any given compound must have been 10,000 times
the minimum detectable limit of the MM5 procedure.
The first of these is merely a demonstration of acceptable analytical
accuracy. The acceptable range is wide relative to normally attainable ana-
lytical precision. It is adequate for this analysis because the ORE calcu-
lation is insensitive to an error of a factor of three in the emission rate
measurement.
The calculation of ORE, the primary use of the data in this document,
is based upon the concentration of the various constituents in the waste
feed stream and in the exhaust gas. The accuracy and precision of these
concentration measurements decrease when they are near the limit of detec-
tion of the analysis methods. Consequently, the dispersion of ORE values
that are calculated based upon these imprecise measurements becomes unac-
ceptably large. The decision was made to include only those data that are
as accurate as is possible using the available methods. The method chosen,
the second of the QA acceptance criteria, accomplishes this goal.
Volatile Organic Sampling Train (VOST)
The basic details of construction and operation of the VOST are described
in the "Protocol for Collection and Analysis of Volatile POHCs Using a Vola-
tile Organic Sampling Train (VOST)1 by Envirodyne Engineers for IERL (Refer-
ence 1). The highlights of the procedure are described below. Stack gas is
drawn through a quartz wool particle filter in a glass or quartz probe heated
to approximately 130°C, through a three-way stopcock and through a coil con-
denser. Following the condenser, the sample gas passes through a glass tube
containing 1.6 g of Tenax*-GC, a condensate trap, a second condenser, and a
second sorbent tube containing 1.0 g Tenax*-<3C followed by 1.0 g of activated
charcoal. A second condensate trap is next, followed by valves, flow meters,
4-6
-------
gas meters, etc. All portions of the sample line preceding the last condenser
are glass, stainless steel, or Teflon®. Figure 4.2 is a schematic depiction
of the train. Previous experiments have established 20 liters as a maximum
safe sample volume for this train. A greater sample volume incurs the risk
of stripping sorbed POHCs off the resin. The sample rate for these tests was
1/2 liters per minute for a total of 40 minutes per pair of tubes.
An ice water batn is used to circulate water through both condensers to
maintain sample gas temperature below 20°C through the sorbent tubes. Tem-
perature of the probe liner, first condenser outlet, ambient air, and dry gas
meter are measured and recorded. Leak checks of the whole train and each pair
of sorbent tubes for each run are conducted and the resulting vacuum is re-
leased by allowing ambient air in through a charcoal filter connected to the
three-way valve.
Tubes used for the kiln tests were of the inside-inside design that are
held in the sample train with stainless steel Swagelok® fittings and ceramic-
filled Teflon* ferrules. Other samplers have used the inside-out-inside de-
sign; a double walled sorbent cartridge/shipping container that uses O-rings
and end caps to seal the cartridges. Stainless steel caps are used t.o seal
tube ends for shipment before and after sample collection. After sample col-
lection, tubes are kept and shipped in chilled styrofoam containers.
The tubes were analyzed on a GC/MS using thermal desorption with trap
and purge. The method is described in the protocol and involves spiking
each tube or pair of tubes with an internal standard, thermally desorbing
the tubes into a water trap, and purging the water trap onto an analytical
column for component separation. Identification and quantification are made
by elution times, characteristic ions, and ion current profile using a com-
puterized data library.
VOST Standardization of Procedure
The protocol provides clear and specific directions about the sample
train to be used and the method of sampling and the method of analysis. Re-
agent preparation, sample handling, QA/QC activities, calibration and calcu-
lations are all described in detail. The protocol states that conditioned
cartridges, as well as used ones with sorbed sample, be kept in ice water
before use and after sample collection. This ice water storage is not re-
quired if acceptable blank levels can be maintained.
Options regarding sample collection and recovery (analysis) efficiencies
are also provided along with evaluation criteria. The analytical procedure
is also described very specifically.
VOST OA/gC Evaluation
The pre-sampling QA activities are clear and direct. Tenax® and char-
coal cleaning, tube packing, and desorption blanking, provide sufficient as-
surance that the sample cartridges start clean. The trip blank, field blank,
and lab blanks are intended to provide a history and background levels of
contamination and/or degradation so that the results of the sample analysis
reflect only POHCs present in the stack gas. This history is especially dif-
ficult to create if the samples and blanks are not analyzed promptly. Sample
4-7
-------
Glcitt Wool
Puillculdlo
rillor
-------
degradation, tube cross-contamination, contamination from external sources
(lab air, ambient air, etc.), and calibration and response standard degrada-
tion become more likely and less distinguishable.
As each analysis is a one time occurrence (no way to split), a bad
analysis, a contaminated or otherwise invalid tube, means a lost data point.
However, the sample collection involves three pairs, so duplication is inher-
ent in the sampling. One could carry this suggestion further to say that two
blanks would be desirable to yield an average value and increase the confi-
dence in the results.
The protocol requires one exposure pair per six pairs of sample tubes.
These exposure (field or shadow) blanks are opened as if they were sample
tubes but are not installed in the train.
One QA action which has not been done, for several reasons, is spiking
tubes in the field with one or aore target POHCs or surrogates to establish
recovery efficiencies. The difficulty stems from two major areas. One is
the difficulty in maintaining reagent and tube purity in a field environment
and the other is not being able to split a single sampling and spike one
portion. The methods used to date have centered on lab simulations and the
analytical process. A suitable field spike procedure would yield data on
sample loss (leakage out) and desorption efficiency as well as additional
data on contamination, lab QA, and overall method validity.
The following list identifies areas where additional effort and investi-
gation could strengthen the VOST procedures.
o Spike blank cartridges in the field with a labeled compound to de-
tect potential leakage during field storage and subsequent transport.
o Analyze the sample immediately with as little storage time in field
and lab as possible.
o Conduct a detailed systematic evaluation of field handling, field
storage, shipping, and lab storage, to identify potential causes of
contamination and/or leakage. Develop guidelines to detect and pre-
vent contamination and to leak check cartridges.
o Investigate the current seal design. Do temperature changes cause
leakage? How can one be certain the tubes are perfectly sealed?
How can overtightening/undertightening be prevented? Can a pres-
sure/vacuum tight seal be obtained repeatedly on a large number of
tubes with no failures?
o Investigate cross-contamination. Place spiked samples and clean
blanks in the same container, store one or two weeks, and analyze.
Do the above with loose fittings or cracked tubes and observe for
cross contamination. Place the sampD.es and lab blanks with their
double seal in an atmosphere containing trace amounts of methylene
chloride or waste fuel vapors, store, and analyze.
4-9
-------
QA acceptance criteria were developed for the VOC data produced during
each test. These criteria could not be identical for all sites since the
methods used differed. In all cases, only those components of waste listed
in Appendix VIII (CFR 40 Pan. 261) were Included in t^ie ORE results; even
though there may have been other organic constituents measured in the waste
feed and stack exhaust streams.
It is noted that not all of the VOC sampling done during these tests
was done by the VOST procedure as has been described. The train used to
sample VOC at Site A consisted of a condensate trap and one Tenax®-GC trap
in series. Do condenser or sorbent temperature control was used at Site A.
Impingers were inserted in the train upstream and downstream of the Tenax®-
GC tube at Site C.
The VOC sampling trains used at Sites A and C varied from the VOST
train in that an impinger (containing water) in an ice bath was inserted in
the sample line ahead of the Tenax*-GC cartridge. Three QA acceptance cri-
teria listed below were applied to the data collected by these trains:
1. If impingers were used, the contents must have been analyzed.
2. Both sorbent tubes must have been analyzed.
3. At least 70% of the total quantity of any compound found on the
sorbent tubes must have been found on the first (Tenax*~GC) tube.
The first two of these are completeness criteria. While analysis of the
condensate is not normally a part of the VOST protocol, it is necessary in
these instances because of the location and the temperature of the condensate
trap. The volume of condensate obtained from a 20-liter sample of stack gas
is approximately 1.5 ml. Even though the compounds of interest (mostly chlor-
inated hydrocarbons) are normally considered to be insoluble in water they
are miscible to a small but measurable extent. A compound soluble to 1 mg/
liter is said to be insoluble yet that translates to 1500 ng/1.5 ml of conden-
sate which is large relative to the analytical quantities of interest. The
VOST train causes the condensate to be drawn through the resin t*d. The re-
sin should remove the compounds from the condensate. Since there was no con-
tact between the condensate and the resin at these sites, it was necessary to
analyze the condensate.
The third acceptance criteria was included to eliminate contaminated
samples from the data. Persons who have sampled surrogate stack gases spiked
with chlorinated )• vdrocarbons under controlled conditions have reported that
at least 90% of ' -se compounds are sorbed on the first resin trap. This is
not true of hic^ly volatile compounds, e.g., vinyl chloride, but it is for
the compounds of interest in this document. Tenax*-GC has sufficient affin-
ity for the? .. compounds to remove them nearly quantitatively from the sample
gas stre-ir. The charcoal, used as a back-up sorbent in the second cartridge,
has a or . n greater sorbent capacity and affinity for these compounds. Thus,
if ta*. cartridges are exposed to contaminants, the second tube should sorb
th r.. at a higher rate. Therefore, setting the acceptance criteria at 70%
allows acceptance of some contamination but rejects grossly contaminated
cartridges.
At the remaining sites (B, D, and F) the VOST train (Figure 4.2) was
used* Acceptance criteria #1 is not applicable but the other two are. Note
4-10
-------
that not all of the test reports contain sufficient data to allow comparison
of the results to the QA acceptance criteria. These data have been accepted
with the expressed reservation that their quality is unknown. The effects
of application of these QA criteria on the data are discussed for each test
in the following pages.
EPA Method 23 (M23)
M23 was proposed by EPA on June 11, 1980, but has not been promulgated
as a reference method. It is a method for determination of the concentra-
tions of low boiling halogenated organic compounds. It is not applicable
to compounds that might condense at ambient temperatures, are sorbed on par-
ticles or are water soluble. It is also not applicable to measurement of
oxygenated compounds (alcohols, ketones) as these appear to be rapidly ad-
sorbed by the sample container.
A sample of gas is collected in an inert (Tedlar* or aluminized Mylar*,
flexible walled bag. The sample is conveyed directly into the bag from the
stack through Teflon* tubing. The bag is placed inside a rigid walled, leak
tight container, evacuation of this container causes expansion of the bag
which draws sample gas into the bag. This system eliminates the need for
contact of the sample with the pump or other potential sources of contamina-
tion. Figure 4.3 is a schematic representation of the sampling equipment the
method specifies that samples be analyzed by a GC with a FID. Some users of
the method have substituted ECDs or Hall electrolytic conductivity detectors
(HECD) for the FID. Both are more sensitive to halogenated compounds than
is the FID. The procedure requires that the analysis be done within two
hours of sample collection. In most cases, this requires that the analysis
be done in the field.
M23 Standardization of Procedure
The method as it appeared in the Federal Register is clear and speci-
fic. The sampling and analysis equipment are described in detail. Clear
and specific instructions are given about sampling and analysis procedures,
QA/QC activities, calibrations, and calculations. The method should be up-
dated to include the HECD and the ECD in order to increase its sensitivity
and specificity.
QA/QC Evaluation
The procedure describes two alternate calibration procedures: one em-
ploys cylinder gases with known concentrations of chlorinated hydrocarbons,
the other employs flash evaporation of known quantities of compounds. Both
require use of the bags during the calibration procedure which provides some
assurance that the sample bags to be used are not unusually sorptive of the
compounds of interest. An additional QA step, spiking stack gas samples,
would provide assurance that water and other stack gas constituents do not
interfere.
The calibration section of the method describes the possibility of cross-
contamination if a low concentration standard is prepared in a bag that has
contained a high concentration standard. The same cross-contamination between
stack samples and between standards and stack samples is possible. There is
4-11
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I
Ff.Ts? tCLASS WOOU
,PflOBs
TEr'.OM
VACUUM UN£
u
i !
STACK WAi.1
8ALI £5" =5 MO SAU
T«nmfl OR
ALUU1NIZEC
UYLARBAS
FIGURE 4.3
METHOD 23 SAMPLING TRAIN
4-12
-------
also the possibility that the bags may have been contaminated dui'ng manufac-
ture or during previous use. These possibilities should be addressed in the
QA procedures. This step could be incorporated easily by requiring that the
leak check be done with pure gases and that the gas be checked for contami-
nants prior to use of the bag. A similar step could be mandated between
separate uses of a bag.
Verification of the cleanliness of each bag prior to its use is required
so trip, field, and laboratory blanks are not appropriate. The requirement
for analysis of the samples within two hours of tneir collection makes sample
splitting impractical. The method could be made more useful by validating
the stability of more compounds in the inert sampling bags. The method is
applicable to more than the seven compounds that the method lists but the
tester must perform a test specific validation study if it is to be used
for compounds not listed in the method.
Results of the test burns conducted, to support the regulatory program
for industrial furnaces are evaluated in the following paragraphs. The
evaluation is presented in three separate categories by type of industrial
furnace. Cement, lime, and lightweight aggregate kilns are discussed as a
single category because these furnaces share many common performance char-
acteristics. The three tests for asphalt aggregate kilns ere presented as
a separate category as is the single test for blast furnaces.
EVALUATION OF TEST BURN RESULTS FOR CEMENT, LIME, AND IWA KILNS
The initial surveys that were performed during the early stages of
development of this BIO revealed that adequate information about the ORE of
hazardous compounds by kilns did not exist. EPA hae also developed exten-
sive data that reported the ORE (ORE includes both thermal destruction and
removal by control devices) of hazardous compounds by incinerators. There
are significant differences in the two processes. Incinerators typically
hold their combustion gases in an oxidizing atmosphere at temperatures ran-
ging from 1800° to 2500°F for times ranging from 2.0 to 3.0 seconds. The
combustion zone temperature in kilns is typically higher (2250* to 3000T)
and the retention time is typically as long or longer (2 to 5 seconds).
Kinetic theory predicts that elementary reactions should be faster at the
higher kiln temperature, faster by a factor ranging from 4 up to 20,000,
depending upon the activation energy of the particular reaction. This
range has been confirmed by thermal destruction analytical system (TOAS)
data for many common hazardous compounds. These data demonstrate that
rates of destruction increase by factors that range from 17 to 12,000 when
the temperature is rained from 1900* to 3100*F (References 3, 4, and 5).
EPA undertook a series of testa to determine whither the destruction
of hazardous materials by co-firing in kilns was adequate to protect th«
environment. Beginning in October 1981, EPA performed tests at six kilns.
An additional test, performed by the State of California Air Resources Board,
has been included in this data set. The sources that have been tested are
characterized in Table 4.2. Three dry process cement kilns, two wet pro-
cess cement kilns, one lime kiln, and one lightweight aggregate kiln are
included.
4-13
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TABLE 4.2
COMPLETED FIELD TESTS ON HAZARDOUS WASTE CO-FIRFD IN KILNS
Site
Desig-
nation
A
B
Kiln Type/Size
Dry Process
Cement
(150,000 Ib/hr
or 1 ,800 TPD)
Wet Process
Cement
(60,000 Ib/hr
or 720 TPl»
Primary
Fuel
Pulverized
Coal ( low
sulfur)
Pulverized
Coal
Waste Description
Mixed solvents
Mixed solvents (65% a r ana-
tic, 1% chlorinated)
Source
Emission
Control
Baghouse
Electro-
static
Preci pita tor
Sampling Matrix
o Flue gas
— Modified Method 23 for vola-
tile organic compounds
— Tenax*-GC train for volatile
organic compounds
— SASS for metals and semi-
volatile organic compounds
and PCBs
— Method 5 for particles, HC1
— Continuous monitors for S02,
NOX, O2» OO, CC>2, and TUHC
o Waste dust
o Waste fuel
o Flue gas
— VOST for volatile organic
compounds
— Modified Method 5 for semi-
volatile organic compounds,
particle metals
— Impingers for HC1
— Continuous monitors for CO2,
NOX, CO. 02, and TUHC
o Waste fuel
o ESP waste dust
o Clinker
o Kiln feed
o Coal
o Slur ry wa ter
-------
TABLE 4.2—Continued
Site
Desig-
nation
Kiln Type/Size
Primary
Fuel
Waste Deccription
Source
Emission
Control
Sampling Matrix
Lightweight
Aggregate
(20,000 Ib/hr
or 240 TPD)
Pulverized
Coal
Solvents, alcohols, ethers,
still bottoms
Cross-flow
Scrubber
o Flue gas
— VOST for volatile organic
compounds
— Method 5 for particles and
metals
— Impingers for HCl
— EPA Method 3 for C02 and °2
— EPA Method 7 for NO,,
I
u>
— EPA Method 6 for
o Waste fuel
o Scrubber blowdown
o Product
o Raw material
o Coal
o Scrubber water
SO-.
Lime
(17,000 Ib/hr
or 204 TPD)
Petroleum
Coke (90%)
Gas (10%)
Solvents, lacquer, thin-
ners, alcohols, still
bottoms, paint wastes
Baghouse
o Flue gas
— VOST for volatile organic
con pounds
— Method 5 for particles,
metals, HC1
— Method 3 for O2 and CO2
— Continuous monitors for NOX,
CO, SO2, TUHC, and O2
o Waste fuel
o Baghouse dust
o Product
o Raw material
o Coal
-------
TABLE 4.2—Continued
Site
Desig-
nation
E
F
Kiln Type/Sice
Dry Process
Cement
(120,000 Ib/hr
or 1,440 TPD)
Dry Process
Cement
(120,000 Ib/hr
or 1,440 TPD)
Primary
Fuel
Coal/
Petroleum
Coke
Mixture
Coal/Coke
Mixture
Waste Description
Solvent reclamation still
bottoms (2-5% CD
Hydrocarbon solvents (2%
CD
Source
Emission
Control
Electro-
static
Preci pita tor
Electro-
static
Preci pita tor
Sampling Matrix
o Flue gas
~ Method 23 for volatile
organic compounds
— Method 5 for particles and
metals
— EPA Method 8 for SO2
— EPA Method 7 for NOX
— EPA Method 25 for TGttIO
— Impingers for HCl
— Continuous monitors for CO,
OC>2 , a nd 02
o Waste fuel
o ESP dust
o Product
o Coal
o Flue gas
— VOST for volatile organic
compounds
— Modified Method 5 for parti-
cles, metals, semi-volatile
organic compounds
— Impingers for HCl
— Continuous monitors for CC>2f
NOX, SO2, CO, O2 and TUHC
o Waste fuel
o ESP dust
o Product
o Raw material
o Coal/coke
o Quench water
0>
-------
TABLE 4.2—Continued
Site
Desig-
nation
G
*
Kiln Type/Size
Wet Process
Cement
(70,000 Ib/hr
or 840 TPD)
Primary
Fuel
No. 6 Oil
Waste Description
Degreaser and pharmaceuti-
cal wastes (6 to 35% Cl)
Source
Emission
Control
Bag house
Sampling Matrix
o Flue qaa
— Method 23 for volatile
organic compounds
— Method 5 for particles and
metals
— EPA Method 6 for SO2
— EPA Method 7 for NOX
— EPA Method 9 for opacity
— EPA Method 10 for CO
— EPA Method 3 for CO2 and O2
— Impinge rs for HC1
•— SASS for semi-volariie
organic compounds
o Process water
o Fuel oil
o Waste fuel
o ESP dust
o Product
-------
The percent fuel replacement chlorine and heat value of the wastes burned
at the various sites are summarized in Table 4.3. More detailed information
about the waste fuels is given in the individual test descriptions.
DREs ef POHCs
j
The data fi™?m all seven test sites (References 6 through 12) were re-
viewed and subjected to the QA acceptance criteria that were presented pre-
viously. The results at each site were compared to the promulgated incine-
rator regulation individually.
The ORE of POHCs in kilns are summarized, by site, in Table 4.4. The
compounds listed are tho^e that were measured in the waste and also listed
(except Freon-113) in Appendix VIII (Reference 13). Particle, HC1, and PIC
emissions are discussed in separate sections that follow the individual test
discussions. Likewise, an overview of the implications of all the data is
presented following the individual test discussions.
Site A
Site A was a dry process cement plant with a production capacity of
150,000 pounds of cement clinker per hour. The primary fuel used at the site
was low-sulfur pulverized coal. A portion of the clinker cooler exhaust gas
is used as combustion air in the kiln. The kiln exhaust gas temperature was
reduced from approximately 1000°F to 575°F by a water quench. Particulate
matter emissions were controlled by a 14-compartment baghouse. Normally,
approximately 100 tons per month of the dust collected by the baghouse are
removed from the system for disposal. This waste rate is sufficient to main-
tain an acceptably low alkali content in the clinker product. During these
hazardous waste combustion tests, the disposal rate was increased to 2000
tons per month. The increased rate of disposal was necessary to remove the
excess chloride that the waste introduced into the system. The waste, mixed
industrial solvents, was supplied by a waste fuel broxer. The waste was ap-
proximately 30% alcohols and ketones, 40% aromatic compounds, and 20% alipha-
tic compounds. It contained approximately 2% chlorine. Waste fuel provided
approximately 30% of the heat input during the co-fired runs.
A total of 31 test runs were performed. Eighteen of these were base-
line runs with the kiln firing coal only. Nine of these runs were done five
months before the 13 co-fired runs and nine during the same week as the co-
fired runs. Only two compounds listed in Appendix VIII were in the waste at
concentrations sufficient to allow computation of DREs. They were methylene
chloride (MeCl2) and methyl chloroform (1,1,1-trichloro«thane).
Two different methods were used to measure the stack gas emission rates
of the two POHCs. One of these was M23, the other was a single Terax* tube
that was preceded by a condensate trap. The M23 sampling and analysis was
done in accordance with the provisional method as published in the Federal
Register. QA/CC data showed that the results were generally credible though
a few results were discarded because of suspected contamination. The results
of the Tenax* analyses also exhibited symptoms of contamination. For example,
the baseline test emission rates of both POHCs were higher (Table 4.4) than
the co-fired emission rates. On the average the Tenax* results were higher
4-18
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TABLE 4.3
WASTE FUEL CHARACTERISTICS OF
HAZARDOUS WASTE CO-FIRED IN KILNS
Site
A
B
C
D
Fraction of Heat
Primary Fuel by Waste (%)
Pulverized Coal
Pulverized Coal
Pulverized Coal
Petroleum Coke
30
40-60
55
8-36
Percent Chlorine Heat Value <
in Waste Waste (Btu/
2 13,800
1-4 12,400
0.9 11,800
3.0 12,900
£ Gas
Pulverized Coal
& Petroleum Coke
Pulverized Coal
& Petroleum Coke
No. 6 Oil
13
35
10
4.b
1.7
25
12,300
12,300
10,200
4-19
-------
TABLE 4.4
DESTRUCTION OF PRINCIPAL ORGANIC HAZARDOUS
CONSTITUENTS IN KIU1S
Site Compound
A
B
C
D
E
F
G
a
b
c
methylene chloride
1,1, l-trichloroethane
1,1,1 -trichloroe thane
methyl ethyl Ice tone
toluene
methyl ethyl Icetone
methyl isobutyl Icetone
perchloroethylene
toluene
methylene chloride
methyl, ethyl ketone
1,1,1 -trichloroe thane
trichloroe thylene
perchloroethylene
toluene
methylene chloride
methyl ethyl Icetone
1,1,1 -trichloroe thane
toluene
Freon-1 1 3
methylene chloride
methyl ethyl Icetone
1,1,1 -trichloroe thane
toluene
methylene chloride
chloroform
carbon tetrachloride
Baseline
Emissions
(No Waste
Feed)
(Ib/hr)
0.0008
0.0012
0.0004
0.0070
0.0360
a
a
a
a
0.00001
0.00006
0.00004
0.00002
0.00002
0.00013
b
b
b
b
0.00308
0.03389
0.00133
<0. 00022
0.01405
0.0108
0.0886
0.5600
Co- Fired
Emissions
( Ib/hr )
0.0003
0.0006
0.0010
0.0050
0.0380
0.0008
0.0004
0.00004
0.00146
0.00002
0.00008
0.00006
0.00003
0.00003
0.00026
< 0.0882
<0.0738
<0.135
<0.0936
0.00040
0.00621
0.00109
<0. 00011
0.00745
0.754°
0.836°
2.140C
Average
Co-Fired
POHC
Feed Rate
( Ib/hr )
15
30
20
50
100
40
20
1
146
1
1-5
2
15
15
35
95
230
50
295
40
16
55
11
150
223
277
126
Test
Average
ORE (%)
99.998
99.998
99.995
99.990
99.962
99.998
99.998
99.997
99,999
99.9974
99.9995
99.9969
99.9998
99.9998
99.9997
>99.909
>99.968
>99.731
>99.968
99.999
99.96
99.998
>99.999
99.995
99.662C
98.698C
98.300C
No baseline run at this sits.
No POHC detected during baseline runs.
Baseline emission rate has
been subtracted*
4-20
-------
than the M23 results by a factor of four. «11 emission rates were low, how-
ever, so that even the DREs calculated from the Tenax® method, without making
allowances for the relatively high baseline measurements, were in excess of
99.99%. The Tenax* results which are given in Table 4.4, demonstrate that
this kiln destroyed more than 99.99% of the POHCs in the waste stream.
Site B
Site B was a wet process cement kiln with a production capacity of 60,000
pounds of clinker per hour. The primary fuel used at this site was pulverized
coal. A portion of the clinker cooler exhaust gas is used as combustion air
for the kiln, the remainder either passes through cyclones prior to its use
-------
the first tube but the baseline emission rate was 30% of the co-fired emis-
sion rate. The ORE of 1,1,1-trichloroethane, calculated without subtracting
the baseline emission, was 99.991 to 99.999%. No Freon-M3 was detected in
any sample. Freon-113 was added to the waste only on test days 8 and 9. A
significant concentration of Freon-113 was found in the sample of waste fuel
taken on test day 7. The average ORE of Freon-113 for thase three test days
was greater than 99.3987%.
The results of these tests, summarized in Table 4.4, indicate that the
kiln destroyed 99.99% of the hazardous material in the waste. This does not
appear to be true of toluene. However, toluene emission rate during the co-
fired tests was not higher than during the baseline tests.
Site C
Site C was a lightweight aggregate process capable of producing 20,000
pounds of expanded clay aggregate per hour. 'The kiln gases were exhausted
through a pair of cyclone dust collectors and then through a cross flow wa-
ter scrubber. Dust from the cyclones was recycled. The water from the spray
scrubber was exhausted to a pond. Scrubber water was not recycled. The dif-
ferences between this process and the cement process was that the maximum
kiln temperature was only 2100°F (opposed to 2800° to 3000°F in cement kilns)
and the product was not alkaline and thus did not scavenge HC1 from the kiln
gases. Note that although the maximum product temperature was 700°F less
than in the cement process, the flame temperature was not less. Less fuel
was burned per unit of product. The temperature of the flame was equal to
the cement kiln flame temperature, but the length of time that the gases re-
main above 2800°F was shortened by the relatively high proportion of product
in the kiln. The liquid waste was trucked directly to the site by generators.
It consisted primarily of solvents, alcohols (10%), esters (5%), and aromatic
compounds (15%). The waste fuel provided approximately 55% of the total heat
input to the kiln during these tests. The balance of the fuel was provided
by pulverized coal. The POHCs of the fuel and their approximate concentra-
tions are given below:
POHC Weight Percent in Waste
Methyl ethyl ketone (HEX) 2.5
Methyl isobutyl ketone (MIBK) 2.0
Tetrachloroethylene (Perc) 0.1
Toluene (MePhi) 8.3
The VOST was used for measurement of the emission rates of the four POHCs
listed above. The VOST was modified, however, by insertion of an impinger up-
stream of the first Tenax* trap. This was done to alleviate the plugging of
the Tenax* traps by condensate that caused abortion of most of the first six
VOST runs. Unfortunately, the condensate was neither measured nor saved for
analysis. A post hoc attempt was made to account for the quantity of POHCs
that may have been lost in the condencate. The procedure consisted of es-
timating the volume of condensate (5 ml), and measuring the concentration
of the POHCs in the scrubber effluent. The concentrations of POHCs in the
condensate was assumed to equal the concentration in the scrubber effluent.
This calculation probably underestimated the quantity of POHCs in the con-
densate since the scrubber effluent consists of condensate that has been
diluted by scrubber water. Not accounting for the dilution may have caused
4-22
-------
the POHC concentration in the condensate to be underestimated by approximate
ly an order of magnitude. Since, the quantity of POHCs in 5 ml of the scrub
ber effluent was approximately equal to the quantity on the Tenax® tubes the
emission rates nay be underestinated by an order of magnitude.
The overall test average DREs for the various POHCs are given below.
These values are those reported by the testing organization:
POHC ORE
99.998
MIBK 99-998
Perc 99.997
Toluene 99.999
They include the estimates of the POHC concentrations in the condensate that
were based on the scrubber effluent concentrations. As was noted, the esti-
mated condensate concentrations may be low by a factor of 10, therefore, the
DREs may be high by one significant figure (99.999 may be only 99.99). with
this adjustment, the DREs of the POHCs approach or equal 99.99%. However, it
is not possible to conclude that 99.99% was attained for certain during these
tests.
Site D
Site D was a lime kiln with a capacity of 17,000 pounds of lime per hour.
Limestone (CaCO3) that was quarried nearby was heated to approximately 2000 9F
to drive off water and carbon dioxide. The product lime was sold as barn lime
and hydrated lime, Ca(OH)2. Approximately 6.5 million Btu of heat per ton of
product provided by a mixture of petroleum coke (90%) and natural gas (10%),
was needed by the process. Secondary kiln air was drawn, preheated, from the
lime cooler. The kiln exhaust gases passed through a series of large radia-
tor coolers and '•.hen through a baghouse before being exhausted.
The waste fuel consisted primarily of lacquer thinner solvents, alcohols,
still bottoms, paint wastes, and a smaller proportion (4%) of chlorinated hy-
drocarbons. The waste was spiked with perchloroethylene (perc) and trichloro-
ethylene (TCE) to bring its chlorine concentration to 3%. In addition to
these compounds, four other hazardous constituents were present in the waste
at concentrations sufficient to allow computation of their DREs. They were:
methylene chloride (MeCl2), methyl ethyl ketone (HEX), 1 ,1 ,1-trichloroethylene
(111-TCE), and toluene. The waste fuel contributed from 8 to 36% of the heat
input to the kiln during these tests. Waste was atomized from a 1-inch diam-
eter pipe that was strapped to the gas burner. The coke was fed through the
annular apace surrounding the gas and waste supply pipes.
The end si? ion rates of the two POHCs, perc and TCE, were measured by the
VOST. HC1 was detetiui.-.-'i by specific ion electrode measurement of the chlo-
ride in the impingers of the Method 5 train.
Typically, the fraction of the various POHCs that were trapped on the
first Tenax* tube ranged from about 50 to 80%. A few pair of tubes contained
less than 50% of one or more POHCs on the first tube. The quantity of the
various POHCs found on the field and laboratory blanks ranged from 50 to 200%
4-23
-------
of the quantity found on the associated sample tubes. These tilings appear to
be the result of contamination. On the other hand, some 20% of the VOST re-
sults are based upon analysis of only one of the two tubes, either the Tenax®
or the Tenax'/charcoal tube having been lost (by breakage or GC/MS malfunc-
tion). The total emission rates (Table A.4) were low and the DREs high, how-
ever. The baseline (no waste feed) emission rates were quite near the co-
fired emission rates. In fact, the difference between the baseline emission
rates and the co-fired emission rates were statistically significant for only
toluene and methylene chloride. Thus, it is concluded that the kiln destroyed
at least 99.99% of the hazardous organic constituents in the waste.
Site E
Site E was a dry process cement plant with a capacity of 120,000 pounds
of cement per hour. This plant had an unusually long (520 feet) kiln with an
unusually long (10 seconds) gas retention time. The added length, and thus
retention time, was needed because the kiln did not have a raw materials pre-
heater. The kiln gases were exhausted through cyclones and then through an
ESP. The dust collected in the cyclones and in the first three ESP banks was
recycled. Dust collected in the fourth ESP bank was considered waste.
The waste burned during these tests was the still bottoms waste of a
commercial solvent reclaimer that normally was used as supplemental fuel by
another cement plant. This waste contained approximately 11% toluene, 8%
methyl ethyl ketone (MEK), 4% methylene chloride (MeCl2), and 2% 1,1,1-tri-
chloroethane. The balance was alcohols, esters, and alkylated aromatic com-
pounds. The four compounds listed were taken as the POHCs for these tests.
The fuel had a chlorine content of 4.5% and a gross heating value of approx-
imately 12,300 Btu/pound. The waste was air-atomized into the primary fuel
(coal and petroleum coke) flame. The waste provided an average of 13% of
the heat input to the kiln during these tests.
The stack gas concentrations of the POHCs were measured by H23. The
lowest concentrations of the POHCs that were detectable by M23 were higher
than the concentrations of tne POHCs in the stack gas. Thus, even though the
flow rates of the various POHCs into the kiln were appreciable it was not pos-
sible to measure them in the stack gas at 99.99% ORE. No POHC was detected
during the co-fired runs but the maximum calculable ORE values ranged from
99.73 to 99.97%. The data demonstrate that the OREs were at least that good
but the method used could not demonstrate 99.99% ORE.
Site F
Site F was a dry process cement plant with a production capacity of
120,000 pounds of clinker per .our. This kiln was similar to Site E in that
there was no raw material preheater so the kiln was unusually long (520 feet)
with an unusually long gas retention time. The kil: was normally fired with
i mixture of pulverized coal and coke. Approximately 65% of the hot air from
the clinker cooler was used as preheated combustion air, the balance was dis-
charged through a cyclone and CSP. The kiln exhaust gases were cooled by
water sprays to 700°F and then passed through a cyclone and an ESP for par-
ticle removal. Approximately 90% of the 225 tons per day of dust that was
collected was recycled. The remaining 25 tons per day was wasted.
4-24
-------
A waste fuel supply pipe was attached to the underside of the coal/coke
burner. The waste was pressure atomized. The waste itself was composed of
hydrocarbon solvents and resins and solids that are typical of paint wastes.
The waste was spiked with 1,',2-crichloro-1,2,2-trifluoroethane (Freon-113).
This compound served &z a surrogate for refractory organic compounds. The
other POHCs that were designated (listed below) were constituents of the
was te.
Compound Weight Percent in Waste Fuel
Freon-113 0.8
Methylene chloride (MeCl2) 0.4
Methyl ethyl ketone (MEK) 0.9
1,1,1-trichloroethane 1.0
Toluene 21.6
Two baseline (no waste fuel burned) runs were done. These were followed by
three co-fired runs. The percent fuel replacement during these runs was 2ii,
37, and 42% for a test average of 35%. The POHC emission rate data from the
final run (42% fuel replacement were invalidated by the analytical laboratory
because the GC/MS internal standard responses were outside of the quality con-
trol range.
The emission rates of POHCs and other organic compounds weie measured
by both the VOST and MM5 procedures. ORE calculations were based exclusively
on the VOST analyses. MM5 samples were analyzed by GC/MS for higher boiling
fuel constituents and for PICs. The VOST sample results were difficult to
interpret. There was evidence that the samples became contaminated. There
were two prime indicators of contamination: high blanks, especially methy-
lene chloride, and the baseline emission rates (see Table 4.4) were higher
for all compounds than the co-fired emission rates. Thus, contamination may
have contributed significantly to the measured emission rates.
The data (Table 4.4) show the ORE of all compounds, except methylene
chloride, to be well in excess of 99.99%. The methylene chloride data were
discounted because of the potential for contamination. There was no indica-
tion (other than the MeCl2 data) that the kiln did not achieve 99.99% DRE
of the hazardous compounds in the waste fuel. The MM5 data, which were less
prone to be influenced by contamination because of the larger quantities of
compounds in the samples, indicated that the DRE of other waste fuel consti-
tuents exceeded 99.99%. It is most likely that the MeCl2 data are in error.
Site G
The kiln tested at Site G was a wet process unit that was producing
70,000 pounds of clinker per hour. The kiln exhaust gases were cooled and
then passed through a baghouse for particle removal prior to their discharge
to the stack. The test report did not state how much of the collected dust
was recycled nor did it describe whether the clinker cooler exhaust was used
as kiln combustion air. The primary fuel burned at the plant was No. 6 fuel
oil.
The was':-/ was a mixture of solvents, primarily alkanes and esters. The
chlorine content of the waste averaged 25% (range 6 to 35%). Most of the
4-25
-------
chlorine in the waste was contributed by three compounds: methylene chlo-
ride (MeCl->), chloroform (MeCl3), and carbon tetrachloride (MeCl^). These
three compounds were designated POHCs. The waste fuel burner pipe was lo-
cated along the inside of the annular primary combustion air conduit of the
oil burner at the 2 o'clock position. The waste was sprayed under pressure
into the oil flame but it was not air or steam atomized. The waste fuel
provided approximately 10% (range 3 to 14%) of the heat input into the Kiln
during these tests.
The data from this site (Table 4.4) do not appear to be similar to the
data from the other six sites. For example, the MeCl4 emission rate measured
during the baseline run is approximately 200 times higher than the average
POHC emission rate during the co-fired runs at the ether six sites. The base-
line results for the other two POHCs, while not so extreme, are also high.
The measured co-fired emission rates are even higher. Note that the baseline
emission rates have been subtracted, the co-fired emission rates given in Ta-
ble 4.4 are the measured rates less the baseline rates. The DREs were calcu-
lated using the baseline adjusted-emission rates. Apparently, this kiln did
a relatively poor job of destroying hazardous compounds.
Particle Emissions
The rates of emission of particles during the baseline and co-fired
tests at the various sites are given in Table 4.5. Combustion of hazardous
waste had an effect on the emission of dust at only Site F. The test report
states that the chlorine from the waste fuel appeared to concentrate in the
small particles. The observation was made at several sites. The Site F op-
erators reported that the added chloride changed the resistivity of the ce-
ment dust enough to seriously degrade the performance of the ESP. The oper-
ators were apparently aware that this might occur and had already consulted
with the manufacturer of the precipitator to explore possible corrective
actions. The increased emissions at Site G were the results of the breaking
of several bags in the fabric filter. The problem first appeared during one
of the baseline runs and was unrelated to the firing of hazardous waste. The
particle emission rates for the six co-fired runs performed after replacement
of the broken bags> was 19.5 pounds per hour (0.068 grains per dry standard
cubic foot at 7% oxygen).
Sites F and C appear to be the only two that did not comply with the
particle emission rate standard for hazardous waste incinerators of 0.08
grains per dry standard cubic foot, corrected to 7% oxygen, site F, ?.s was
mentioned, apparently developed a correctable dust resistivity problem as a
result of burning the chlorinated waste. Site C was equipped with only a
cross flow water scrubber that cannot be expected to remove particles effi-
ciently.
HC1 Emissions
The measured rates of chlorine input in the fuel (waste fuel plus pri-
mary fuel) were compared to the stack gas emission rates of gaseous chloride
in Table 4.6. Thes« data demonstrate that the alkaline product effectively
scavenges HC1 from the combustion gases. Several of the test reports noted
that the bulk of the chloride appeared to be associated with the fine parti-
cle fraction of the dust that was suspended in the kiln exhaust gases. The
4-26
-------
TABLE 4.5
PARTICLE EMISSION RATE FROM KILNS
Particle Emissions
Baseline
Site
A
B
C
D
E
F
G
C*
Ib/hr
NMb
19.7
c
2.0
49.6
52.5
21.7
gr/dscfa
NM
0.053
c
0.013
0.069
0.164
0.069
Co-Fired
Ib/hr
NM
19.0
11.7
2.2
58.4
240.0
30.7
19.5
gr/dscfa
NM
0.052
0.182
0.013
0.080
0.828
0.117
0.068
a Corrected to 7% Q£ as required by incinera-
tor regulations.
k Not measured.
c No baseline run at this site.
d Co-fired runs after replacement of broken
bags.
4-27
-------
TABLE 4.6
HYDROCHLORIC ACID EMirSION RATE FROM KILNS
Site
A
Co-Fire
B
Baseline
Co-Fire
C
Co-Fire
D
Baseline
Co-Fire
E
Baseline
Co-Fire
F
Baseline
Co-Fire
G
Baseline
Co-Fire
Chlorine in
Fuel (JL/hr)
156
13.3
129.3
22.0
1.6
28.6
36
178
22.9
149.1
NO13
351.0
Chloride in Sc^ck
Gas (Ib/hr)
Occ
1.03
<1 .8
3.52
0.051
0.20
0.44
3.7
3.2
2.9
25.3
0.34
0.96
Removal
Efficiency
99.34
86.47
97.28
97.77
87.50
98.46
89.72
98.20
87.34
83.03
99.73
a No baseline run at this site.
0 No chlorine detected in No. 6 oil.
4-28
-------
rate of waste of dust collector fines had to be increased to prevent exces-
sive buildup of chloride in the product at the cement plant. The increased
rate of production of waste dust was not seen to be a major hardship. The
rate of eirassion of HC1 at Site F was significantly higher during the co-
fired tests than at the other sites. It is believed that these samples were
contaminated by the high concentration of chloride laden dust. Sites E and
F were similar facilities and showed similar HC1 removal on baseline tests.
Site C was an expanded clay aggregate kiln. Neither the raw material nor the
product of this plant was sufficiently alkaline to absorb significant amounts
of chloride. However, the kiln was equipped with a wet scrubber that effi-
ciently removed the HC1 from the gas stream. If Site F is ignored, .he kiln
dust clinker and control equipment collectively removed 97% or greater of the
HC1 from hazardous waste combustion on six kiln tests.
Products of Incomplete Combustion (PICs)
Compounds not present in the fuel or waste fuel burned appeared in the
exhaust gas of several sources. There are two general mechanisms by which
PICs may be formed. One is formation of products of partial oxidation of
fuel components. The formation of aldehydes during incineration of refuse
is an example of this mechanism. Formation of low molecular weight hyaro-
carbons (C-j-Cg) during combustion of coal and heavy oil fuels is another
example. The second general mechanism is a reaction o* free radicals or
other molecular fragments produced in the high temperature flame to produce
different compounds. The products of these reactions may have higher mole-
cular weights than the fuel components. Benzene, polynuclear aromatic com-
pounds, and soot particles appear to be formed in this manner.
There are also means by which fuel-absent compounds may appear in the ex-
haust gas that are unrelated to the combustion. Perhaps the major source of
fuel-abse ,t compounds is the raw materials. These materials are sedimentary,
usually rock, but sometimes oyster shells, argonlte, etc., all of which inher-
ently contain greater or lesser degrees of biogenic material, often residual.
Levels can be as high as a few percent of the total raw materials. This bio-
genic material contain organic compounds that often will be drivenoff at low
temperatures and av^ear in the exhaust gases without having any opportunity
to be combusted. Other sources of fuel-absent compounds include evaporation
of lubricating oils from mechanical equipment downstream of the kiln and com-
pounds that were present in the ambient air that was used in the furnace.
The water used in wet process cement slurry or in the scrubbers at lime and
aggregate kilns may be a source of organic compounds. These may exist in the
fresh water supply, be introduced by other processes where water re-use is
practiced, or they may have be
-------
have attributed the presence of several C^-Cg alcohols and ketones in exhaust
gas samples to the degradation of XAD resin. In addition, there is evidence
that compounds sorbed by porous polymer resins are not quantitatively removed
daring their preliminary cleanup. Successive cleanings release additional
amounts of these compounds. Thus, it is possible that a measured compound
may be the residue of some past sample or contamination.
Benzene emissions were reported at Sites A and B. These emissions (Ta-
ble 4.7) occurred during both the baseline and the co-fired test runs. There
was not enough data to establish whether these reported emissions were due to
primary fuel coubustion, waste fuel combustion or analytical artifacts. No
other significant PIC emissions were reported.
Metals Emissions
The metals emissions data that were available (Table 4.8) did not indicate
that the combustion of was**? ruei increases the rate of emission of metals by
more than would be expected from their increased firing rate. For example, the
firing rate of lead (Pb) was five times higher during the cofired run at Site B
than it was during the baseline run, and its emission rate increased by a factor
of five. The fraction of those metals in the fuels that have been shown to con-
centrate in small particles (all except Ni in Table 4.8) emitted to the atmos-
phere was higher than the fractional emission of other metals. The amount of
even the volatile elements emitted was less than tns amount in the waste fuel;
i.e., approximately 15% of the mercury (Hg) in tb-j waste fuel at Site B was
erai tted.
None of the metals sought at Site A were detectable in the stack gas par-
ticles, primarily because the total mass of sample was low. The waste burned
at Site G contained negligible concentrations of metals. Thus, no baseline to
co-fired test comparisons were possible for these sites. The mass emission
rates of all dust constituents was high during the co-fired tests at Site F
because the chloride increase in the dust that occurred from burning the waste
changed the dust resistivity and degraded the performance of the precipitator.
Those emissions were not representative of normal operation and were not. in-
cluded in the tabla.
Thv metals emissions data at Site C demonstrated the effect of concentra-
tion of certain elements in small particles. This site was equipped with a
crossflow water scrubber that was ineffective at removal of small particles.
The fraction of thfc fuel-contained volatile metals (Pb and Cr) emitted in the
stack gas was approximately four times higher at this site than it was at the
other sites.
Combustion Gases and DRE
Table 4.9 contains average values for combustion gases plus NO2 and the
CREs of two hazardous compounds. No single hazardous compound was common to
all sites. The CO2 concentrations were high and, except at Site C, were not
representative of combustion conditions, since at all other sites limestone
was being calcined. There was no indication why both the unburned hydrocar-
bons and the NOX concentrations at Site E should be so much higher than thay
were at the other sites. Site E DRE data cannot be coansrsd to the other
sites since there was no upper bound for them. No meaningful correlation
4-30
-------
TABLE 4.7
PRODUCTS OF INCOMPLETE COMBUSTION FROM KILNS
Site
A
B
C
D
E
F
G
Baseline
Compound ( Ib/hr )
benzene
PCBs
perchloroethylene
benzene
chloroform
NO ATTEMPT MADE TO MEASURE
NO ATTEMPT MADE TO MEASURE
NO ATTEMPT MADE TO MEASURE
NO COMPOUNDS NOT IN WASTE
aromatic compounds
polynuclear aro-
matic compounds
sulfur
0.4
0.007
0.29
0.001
PICs AT THIS
PICs AT THIS
PICs AT THIS
WERE FOUND IN
_—
Co-Fire
(Ib/hr)
0.6
<0.001
0.008
1.25
0.005
SITE
SITE
SITE
STACK
0.0002a
0.0002a
0.00003a
a Compounds found during co-fired runs that w«re not found
during baseline run.
4-31
-------
TABLE 1.3
METALS EMISSION RATES FHOM KILNS
Mass Flow Rat.es (Ib/hr)
Baseline Tests
Co-fired Tests
Site
Metal
Fuel Total
Exhaust Gas
Fuel Total
Exhaust Gas
None
Detected
Cd
Cu
Hg
Ni
Pb
Se
Cd
Cr
Pb
Pb
Zn
0.007
<0.345
<0.002
0.809
0.485
0.009
0.098
0.032
<0.00001
<0.0004
<0.0001
0.001
0.012
0.004
<0.006
0..001
13
676
009
113
396
0.080
0.034
0.80
5.0
0.265
0.221
0.005
<0.001
0.001
<0.0004
0.055
0.027
0.006
0.016
0.43
0.004
0.005
E
F
G
Mass flow rates of metals were not calculated
Electrostatic precipitator malfunction
Metals in waste fuel were negligible
4-32
-------
TABLE 4.9
AVERAGE FLUE GAS CONCENTRATIONS OF COMBUSTION GASES FROM KILNS
1
Id
u>
Site
A
B
C
D
E
F
G
°2
Base-
line
8.3
12.3
b
7.1
5.3
6.5
12.1
(%)
Co-
Fire
8.9
12.0
13.6
5.6
5.4
7.2
11.8
co2
Base-
line
17.0
12.9
b
23.6
24.2
23.6
15.3
(%) CO (ppm)
Co-
Fire
16.2
13.1
1.5
22.0
23.3
22.4
14.7
Base-
line
64
212
b
426
3.3
37.5
166
Co-
Fire
40
190
a
646
4.0
38.7
326
TUHCe
Base-
line
a
10.2
a
8.4
1?55C
2.5
9.0
(ppm)
Co-
Fire
a
21.0
a
3.6
469°
5
12.7
N0y (ppm)
Base-
line
682
371
b
376
1600
620
136
Co-
Fire
486
477
161
422
9o9
814
6P
ORE
Methylene
Chloride
99.998
a
a
99.997
>99.909d
99.960
99.662
(%)
Toluene
a
99.990
99.998
99.999
>99 368^
99.99'j
a
a Not measured.
b No baseline run at this site.
c Total gaseous normethane organic matter.
d None detected. ORE calculated based on minimum detection limit of Method 23.
e Total unburned hydrocarbons.
-------
between ORE and any PIC could be found. Nor was there any indication that
a threshold concentration of any combustion gas, beyond which ORE was atten-
uated, exists.
Regulatory Implications of Test Burn Data
The data indicate that, where alkaline material is produced, the HC1
that results from combustion of chlorinated organic material is absorbed by
the material. Thus, the HC1 emissions are all low. There is no indication
that the burning of hazardous waste affected the rate of particle emissions,
except at Site F, where the excess- chloride in the dust during co-firing ap-
peared to change the resistivity of the dust and degrade the performance of
the ESP. This was not observed at the other three sites (B, G, and E) that
were equipped with ESPs and was thought to be correctable at Site F. Only
Site C, which was equipped with only a crossflow water scrubber, emitted
particles at a rate in excess of 0.08 grains per dry standard cubic foot,
corrected to 7% oxygen. Thus, it is evident that hazardous materials can
be burned in lei Ins without causing excess emissions of HC1 and particles.
The metals emissions data indicated the need for a fuel specification/
control device specification regulation. The combination of a control de-
vice that is ineffective for small particle removal and a high concentration
of volatile, hazardous matals could result in excessive emissions.
The ORE data demonstrated that it is possible for kilns to achieve ade-
quate (99.99%) destruction of hazardous org?nic compounds. However, it was
not demonstrated conclusively at ill sites nor have a complete spectrum of
all equipment types and operating conditions been sampled. Kilns are subject
to variations in design and operating conditions in response to variations
in raw material compositions and product specifications. The population of
kilns cannot be easily categorized. Therefore, to be environmentally cer-
tain, regulations would need to require that a trial burn be done at each
site where combustion of hazardous organic compounds was contemplated. Care
should be exercised in the design of theje trial burns to assure that the
combination of POHC selection and stack gas test method will bound the ORE
at 99.99% or higher.
EVALUATION OF TEST BURN RESULTS FOR ASPHALT AGGREGATE KILNS
Interest in the level of emissions from burning waste derived fuels in
asphalt concrete plants has grown as the practire has increased throughout
the industry. The State of Texas conducted emission testing at an asphalt
concrate plant (Reference 13> due to high occurrence of chlorinated compounds
in their fuel. The results showed that destruction efficiencies did exceed
99.99% for most chlorinated species tested. The report concluded that down-
wind concentrations neither adversely affect the environment nor posed any
health effects frc:.i public exposure.
Sampling performed for the Massachusetts Asphalt Pavement Association
(MAPA) on spiked waste derived fuel (Reference 14) showed that the particu-
late limits (NSPS) were met but trichloroethylene had a destruction removal
efficiency of 99.75% and Hydrochloric acid was emitted at 4.81 pounds per
hour with an overall removal efficiency of 81.96%.
4-34
-------
EPA tested three asphalt plants to provide data to support developing
regulations for burning hazardous waste in asphalt plants (Reference 15).
The goals for the test program were to:
o Determine the ORE of two POHCs (perchloroethylene and chlorobenzene)
in a batch plant and a drum-mix plant.
o Determine metals removal efficiency by a baghouse and a scrubber.
o Evaluate HC1 emissions from a baghouse-equipped unit and a scrubber-
equipped unit.
Initially, it was decided to sample a drum-mix plant equipped with a
baghouse (Plant A) and a batch plant equipped with a scrubber (Plant B).
When Plant B was tested, cyclonic flow in ths stack precluded sampling for
particulate (metals). A third plant (Plant C) was added to the program to
supplement the metal iata for the "batch plant equipped with a scrubber".
Plant A is a 1984 vintage Barber-Greene 400 ton per hour drua-raix plant
equipped with a baghouse. The unit is described as a "six-pack* because it
is mounted on six flat bed trailers for easy relocation. The fuel was 100%
recycled oil, primarily from industrial sources. Due to heavy rain prior
to the test program, the aggregate had a high moisture content. Therefore,
production was limited to 295 tons per hour during the test program. The
average fuel consumption was 500 gallons or 100% waste oil per hour or about
1.7 gallons per tor of concrete produced.
Plant B is a 1950's vintage batch plant equipped with primary cyclone
and low efficiency scrubber. The fuel oil was 100% recycled oil, primarily
crankcase oil. The hourly production rate was 195 tons per hour burning 390
gallons per hour of 100% waste oil. Fuel consumption was 2.0 gallons per ton
of product.
Plant C is a 1950's vintage batch plant equipped with a primary cyclone
and a medium to high efficiency scrubber. The fuel fired was 100% recycled
crankcase oil. Plant C had the lowest production capacity at 76 tons per
hour, burning 165 gallons per hour of 100% waste oil. This is equivalent
to 2.2 gallons per ton of product.
Plant A represents a typical modern type plant (drum-mix design) with
a high efficiency particuiate collector (baghouse). Plants B and C repre-
sents older type plants (batch process) with low to medium efficiency parti-
cuiate collectors (water scrubbers).
Two exhaust gas test locations were sampled on the plants. The inlet
of the control device was sampled for particulates and metals only. The
stack was also sampled for particulates and metals to allow determination
of control equipment removal efficiencies. Additionally, the exhaust stack
was sampled using EPA MM5 for POHCs and a MM6 for KC1. CEMs were used for
monitoring oxygen, carbon monoxide, and total hydrocarbons. The OEMs were
used primarily for monitoring the process to insure against sampling during
upset conditions.
4-35
-------
Table 4.10 summarizes the production data for the three units and con-
tains stack exhaust gas data including moisture, temperature, oxygen content,
and gas flow rate au standard conditions.
Two target compounds were used to measure the ORE of the plants; per-
chloroethylene and cMorobenzene. Ths compounds were injected irto the burn-
er fuel line between the fuel tank and the burner. This approach provided
several advantages over spiking the fuel in the tank.
o The fuel tanks were not contaminated.
o It was not necessary to mix the fuel to avoid stratification.
o It was much easier (and more accurate) to monitor the actual POHC,
injection rate using calibrated rotometers.
The sampling method used was EPA MM5 with XAD-2 as the sorbent trap.
The analytical method followed SW846 guidelines for GC/MS. The two target
compounds were injected into the fuel at rates to approximately 1% by weight
of the fuel. Samples of the fuel oil were collacLew airing each test and
submitted for analysis. The actual feed rates and feed oil concentrations
of the target POHCs are provided in Table 4.11.
The measured DREs are presented ir Table 4.12. Plant A is the drum-mix
plant and Plant B is the batch plant. In ztost cases the DREs are reported
to one place beyond actual sensitivity of the method. That estimated deci-
mal is underlined to indicate that it is an approximation. In a few cases,
perchloroethylene was observed but it was below the reported detectable limit
-------
TABLE 4.10
AVEKAGE PRODUCTION DATA AND EXHAUST GAS CHARACTERISTICS
Plar.t Type Controls
Production Data
Waste Asphalt
Oil Concrete
(gph) (tph)
Exhaust Data
Gas Gas Oxygen Gas
Moist. Temp. Content Flow
(%) (°F) (%) (dscfm)
Drum- Baghouse 501 295
mix
Batch Spray 389 195
scrubber
Batch Venturi 165 76
scrubber
37
18
12
280 10.1
21,900
142 12.6 24,460
134 16.0 16,470
4-37
-------
TABLE 4.11
POHC FEED RATES AND RESULTING CONCENTRATION OF THE FUEL
Perchlorcethvlene
Chlorobenzene
Grams/Minute
Percent of Fuel
Grams/rtinutt
Percent of Fuel
PLANT A
Test 1
Test 2
Test 3
Test 4
PLANT B
250
178
406
435
0.87
0.66
1 .40
1.50
255
269
319
377
0.88
1.00
1 .10
1.30
Test 1
Test 2
Test 3
85
86
86
0.34
0.44
0.44
185
176
176
0.74
0.30
0.90
4-38
-------
TABLE 4.12
MEASURED DREs AT PLANTS A AND B
Perchloroethylene (%) Chlorobenzene (%)
PLANT A
Test 1 - 99.997 99.99_1_
Test 2 = 99.99J[ 99.98£
Test 3 > 99.997^ 99.9915^
Test 4 > 99.9997^ 99.994J_
PLANT B
Test 1 > 99.95^ 99.94
Test 2 =. 99.99_ 99.95
Test 3 > 99.92 99.96
4-39
-------
TABLE 4.13
METALS CONCENTRATIONS IN THE AGGREGATE AND
WASTE OILS OF PLANTS A AND C
Metal
Arsenic
Aluminum
Boron
Barium
Cadmi-im
Calcium
Chromium
Iron
Lead
Magnesium
Manganese
Molybdenum
Nickel
Silicon
Silver
Sodium
Tin
Titanium
Vanadium
Zinc
Plant A
Aggregate
(ppm)
not analyzed
1,300
0.0
4.4
4.7
150,000
2.7
5,900
11
48,000
380
5.1
8.0
2/0
<3.0
160
<30
42
7.3
15
Waste
Fuel
(ppm)
•••
295
<1.0
23.8
<0.?
42.5
287.5
570
71.8
11.5-14
5.3
8.1-9.6
3.4
69.3
1.7-3.9
0-20
0-50
1.8-2.3
10
67
Plant
Aggregate
(ppm)
«»•«
5
1,930
10
0-1
58,300
11
8,120
7
3,590
88
4
7
665
0-1
23
0-10
73
10
10
C
Waste
Oil
(ppm)
•«•
0-1
22
26
1
571
3
188
416
286
7
7
4
150
0-1
385
0-10
0-5
12
593
4-40
-------
Although a few of the metals were present in the oil in much greater
concentrations than in the aggregate (Plant A - barium, chromium, lead, and
zinc; Plant B - boron, barium, lead, sodium, and zinc), the feed rate of the
aggregate was over TOO times the feed rate of the fuel oil on a weight to
weight basis. This precluded tracking the fate of a given specific metal
from the oil through the system.
Another approach was taken for evaluating the metals data. Based upon
t*e relative feed rate of the aggregate and fuels oils (hundreds of tons per
}A ir of aggregate to 1 or 2 tons per hour of oil) it was hypothesized that
the metal concentration of the particulate catch at the control device in-
let should be similar to the metal composition of the aggregate. 'Theoreti-
cal metal loadings were calculated in pounds per hour at the baghouse inlet
assuming that the particulate catch there was predominantly aggregate. The
potential contribution from the waste oil v/as then calculated assuming that
all of the metals in the oil reachr1 the control device inlet. Finally, the
actual metal loading was determined from analyses of the Method 5 particulate
catch. The results are compared in Tables 4.14 and 4.15 for Plants A and C,
respectively. From these results it appears that the waste oil contributes
i. significant portion of aluminum, barium, chromium, iron, lead, molybdenum,
nickel, silicon, and zinc to the particulate material at the control device
inlet of Plant A, and boron, barium, chromium, lead, sot'j.um, and zinc at
Plant C. The results are not conclusive, but are indicative especially that
the barium, chromium, lead, and zinc from the waste oils are emitted from
the asphalt kilns into the control equipment.
Table 4.16 shows the overall particulate control efficiencies of tha
baghouse (99.75% efficiency) and scrubber (99.24% efficiency). Table 4.17
presents the range of measured control efficiencies for each of the metals
at the two plants. The efficiencies for the metals deduced as being from
the fuel oils are underlined in the table. Most metals were controlled as
efficiently as the total particulate loading in the baghouse. However, the
scrubber was not as efficient for several metals including lead, sodium, and
zinc. A baghouse is generally as efficient for small particulate as it is
for large, whereas the efficiency of the scrubber decreases with the particle
size. Some of the metals are possibly more concentrated in the finer parti-
cles and therefore collected more efficiently by a baghouse than a scrubber.
Plants A, B, and C were all sampled for HC1 emissions using a midget
impinger train. The samples were analyzed by specific ion electrode. The
inlet of the venturi scrubber on Plant C was also tested. Samples of the
feed oils were also analyzed for total chloride content. The chloride con-
centrations in the waste oils burned at the three plants varied significant-
ly. The concentrations were 1.6, 0.5, and 0.1% by weight for Plants A, B,
and C, respectively.
Plant A burned industrial waste oil whi"Ji contains "extreme pressure"
(EP) lubricants which eire long chain chlorinated hydrocarbons.
The stack gas samples at all locations were found by analysis to be be-
low the detection level of the method, which is approximately equivalent to
30 ppm of HC1 in the stack gas or less than 0.5 pounds per hour at Plants A
and B. The sample volume was increased at Site C so that the minimum detect-
able concentration was 0.4 ppm or equivalent to 0.03 pounds per hour. HC1
4-41
-------
TABLE 4.14
COMPARISON OF THEORETICAL METAL CONTRIBUTIONS FROM
AGGREGATE AND WASTE GIL TO ACTUAL ME,\3UKEb METAL
LOADINGS AT THE CONTROL DEVICE INLET, PLANT A
Metal
Aluminum
Boron
Barium
Cadmium
Calcium
Chromium
Iron
Lead
Magnesium
Manganese
Molybdenum
Nicfcel
Silicon
Silver
Sodium
Tin
Titanium
Vanadium
ilinc
Aggregate*
200
<0.15
0.68
0.72
23,000
0.41
906
1.7
7,370
58.3
0.78
1.23
41.5
<0.46
24.6
<4.61
6.45
1.*2
2.30
Waste Oil
113
<0.38
9.08
<0.11
16.3
110
218
27.4
4.88
2. 01
3.38
1.28
26.5
1.0
<7.7
<19.1
0.76
<3.83
25.6
Aggregate Plus
Waste Oil
313
<.38
9.76
0.72
23,000
110
1 , 1 24
29.1
7,370
60.3
0.78
2.51
68.0
0.5
24.6
<19.1
6.45
1.12
27.9
Actual Measured Loading
(pounds per aour
x 10-2)
374
ND
7.79
0.2
25,400
101
1,165
39.8
9,330
38.2
3.75
3.68
68.6
0.6
47.9
9.63
12.8
1.68
24.2
Metal concentra'i-, in the bulk aggregate multiplied by the mass flow rate
of dust in the flu« ,as.
4-42
-------
TABLE 4.15
COMPARISON OF THEORETICAL METAL CONTRIBUTIONS FROM
AGGREGATE AND WASTE OIL TO ACTUAL MEASURED METAL
LOADINGS AT THE CONTROL DEVICE INLET, FLANT C
Metal
Arsenic
Aluminum
Boron
Barium
Cadmium
Calcium
Chromium
Iron
Lead
Magnesium
Manganese
Molybdenum
Nickel
Silicon
Silver
Sodium
Tin
Titanium
Vanadium
Zinc
Aggregate*
0.13
52.4
<0.05
0.27
<0.03
1,585
0.30
220
0.20
97.6
2.39
0.10
0.20
18.1
<0.0^
0.63
<0.27
1.98
0.27
0.27
Waste Oil
<0.12
2.72
3.22
3.22
0.14
70.6
0.32
23.3
51.5
35.4
0.84
0.90
0.43
18.6
<0.12
47.6
0.27
<0.62
1.48
73.4
Aggregate Plus
waste Oil
0.13
55.1
3.27
3.49
0.17
1,656
0.62
243
51.7
133
3.23
1.00
0.63
36.7
0.15
48.2
1.51
2.60
1.75
73.7
Actual Measured Loading
(pounds per hour
x 10-2)
0.23
150
0.14
0.92
0.04
5,476
0.97
445
13.48
371
7.59
0.36
2.12
10.7
0.05
14.7
0.24
3.96
0.85
21 .0
Metal concentration in the bulk aggregate multiplied by the mass flow rate
of dust in the fluo> gas.
4-43
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TABLE 4.16
PARTICULATE LOADINGS *ND CONTROL DEVICE EFFICIENCIES
Plant
A
C
Sample Location
Inlet of Baghouse
Outlet of Baghouse
Inlet of Scrubber
Outlet of Scrubber
Tarticulate
Concentration
(gr/dscf )
8.9
0.020
2.32
0.015
Parti culate
Loading
llb/hr)
1536
3.96
271. S
2.07
Control
Efficiencies
(%)
99.75
99.24*
The venturi was operating at a pressure drop of 16-17.5 inches of
water.
4-44
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TABLE 4.17
METAL CONTROL EFFICIENCIES: PLANT A AND C
Air Pollution Control
Device Efficiencies
Metal
Arsenic
Aluminum
Boron
Barium
Cadmium
Calcium
Chromium
Iron
Lead
Magnesium
Manganese
Molybdenum
Nickel
Silicon
Silver
Sodium
Tin
Titanium
Vanadium
Zinc
Plant A (%)
Not analyzed
TOO
NA
0-100
99-1 00
98-100
100
100
89-100
70-100
98-1 00
100
0-100
0-100
89-100
1 0-1 00
0-100
82- JB
0-100
35-97
Plant C (%)
87-100
100
77-100
99-100
56-81
100
85-93
99
25-42
100
97-99
67-78
94
64-79
65-81
36-56
0-36
99-1 00
81-94
25-28
4-45
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was still not detected in any of the samples. The results are presented in
Table 4.18 with the estimated equivalent HC1 fuel feed rate.
HC1 samples were collected at th_ inlet to the scrubber at Plant C.
Because the results at the inlet of the Plant C scrubber were also below the
detectable level (0.03 pounds per hour) it appears that the chlorides may be
attracted to the aggregate which was 60% doj.omitic lime at the sites tested.
It appears from these test results that burning chlorinated waste at
chloride inputs at the levels used in the test are not likely to result in
an air pollution problem. It is quite possible that the chlorides react with
the calcium in the aggregate during the drying process. This has been demon-
strated to occur during hazardous waste incineration in cement kilns.
EVALUATION OF TEST BURN RESULTS FOR BLAST FURNACE
A blast furnace should obtain greater than 99.99% ORE of toxic organics.
However, no actual testing dar.a are currently available to substantiate this
expected performance. The single test conducted by EPA to evaluate :ypical
waste disposal performance of a blast furnace when burning a liquid organic
waste (Reference 16) is deemed invalid. There were several problem/ with the
test. One major problem was that the waste feed POHC composition viried sig-
nificantly during the test runs. This introduced error in the calculation
of the ORE because of uncertainty in the amount of the POHC3 in th'i feed.
Another problem was that the POHC loading on some of the blanks for the VCST
analyses were higher than the sample loadings. Also, for son® of the POHCs,
the DRE across the blast furnace was higher than that measured across the
blast furnace and stoves. Still another shortcoming of the test.'; was that
there were no provisions made for determining whether the POHC collected
from the gas stream was PICs from the combustion of coke and fu«l oil or
was a constituent of the hazardous waste.
Although the single test was invalid, it is deemed very likely that
POHCs would be destroyed by a blast furnace system with a ORE of over 99.99%
because the fraction escaping destruction in the blast furnace is passed
through another combustion device. It is expected that the stoves and boil-
ers in which the off-gas is combusted should be capable of the sane level of
DRE as the industrial boilers for which testing has demonstrated over 99.99%
DRE of toxic orgarJ.cs with regard to the off-gas that is flared, results from
several studies (References 17-19) indicated over 98% DRE of the organic com-
pounds can be expected if the flares are operated such that a stable flame
is maintained, i.e., flame stays lit. Under unstable conditions, however,
the flare destruction efficiency can be reduced to approximately 55% (Refer-
ence 17).
To date, EPA has not conducted any tests to determine the fate of metal
constituents of hazardous waste burned in blast furnaces. These toxic metals
would, like metals in the raw materials, be partitioned between the slag, pig
iron, and the off-gases according to their physical and chemical properties.
Those that leave the furnace in the off-gases will be pass through a high ef-
ficiency air pollution control system, it is conceivable that baseline emis-
sions (i.e., without burning hazardous waste) of a metal could exceed even-
tually adopted limits. la this situation, the owners and operators may be
4-46
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TABLE 4.18
COMPARISON OF HYDROGEN CHLORIDE
EMISSION DATA AND CONTROL EFFICIENCIES
HC1 Input HC1 Emissions Control
Plant (Ib/hr) ( ib/hr) Efficiencies (%)
A 62.3 <0.38 >99.4
B 15.5 <0.56 >96.4
C 1.3 <0.03 >97.7
4-47
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required to burn hazardous waste with metal levels below specified limits
instead 01 being required to meet mass emission rate limits.
As with toxic metals, thera c.re no definitive data on the fate of chlo-
rides in hazardous waste burred in a blast furnace. The chloring in chlori-
nated wastes would likely be converted to a metal halide which would probably
be removed in the slag. Any HC1 that is formed would have to pass through a
ben of lime at some point near the top of the furnace. The burden contains
limestone which is converted to lime as it travels downward in the furnace.
This lime would likely neutralize most of the HC1 formed from the combustion
of chlorine-containing wastes. The air pollution control system would cap-
ture some of the HC1 that might pass out of the blast furnace.
SYSTEM MODIFICATIONS NECESSARY TO BURN HAZARDOUS WASTES IN INDUSTRIAL FURNACES
In order to fire hazardous wastes in existing industrial furnaces certain
modifications may be necessary, including:
o Installing waste storage and handling facilities.
o Installing equipment to characterize the wastes.
o Installing equipment to pretreat the waste to improve its suitability
for firing.
o Adding a burner gun for firing the waste or replacing the existing
gun with a multi-fuel burner designed to burn several fuels singly
or in combination.
o Upgrading combustion process controls to handle the waste fuel.
o Providing waste feed rate, oxygen, and carbon monoxide monitoring to
ensure that adequate destruction of the waste is achieved.
o Updating the air pollution control system to meet imposed emission
limits.
Waste Storage and Handling
A significant number of furnaces are used in industries which do not
generate hazardous waste suitable for burning as fuel. Thus, waste burned
in industrial furnaces is often received from off-site. Waste may arrive at
the furnace location in tank trucks, rail tank cars, by barge, or other spe-
cial means.
Although it is possible to feed the waste directly from these transport
units, it is desirable to provide for some short-terra on-site storage. Un-
1jading facilities are needed to transfer the waste from the hauler to the
storage tanks. Because the properties of tnese wastes are almo^c always very
different from the raw materials and products handled a. the furnace sites,
existing unloading facilities are often inadequate for transferring hazardous
wastes. Possible exceptions are facilities which use oil as the primary fuel
for the furnace. It may be possible to use the oil unloading facilities at
4-48
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some of these plants to transfer the waste to storage. As discussed earlier
in this document, however, most cement, lime and lightweight aggregate kilns
are fired by coal.
The requirements for hazardous waste storage and handling are oeing
developed in a separate regulatory analysis by EPA OSW and should be con-
sulted before designing and constructing such facilities. The subject will
therefore not be dis'^issed further in this document.
Characterization and Pretreatment
As previously mentioned, essentially none of the potential hazardous
wastes burned in industrial furnaces, particularly by the cement, lime, and
lightweight aggregate industries are produced oy these industries. The ma-
jor exception to this generalization is in the pulp and paper industry where
wastes from pulping processes are often burnjd as fuel in the kilns used for
regenerating lime from lime sludge. Since the wastes are generated off -site,
kiln operators can be selective as to which they will accept for burning.
They are not forced to chose between firing the waste in the kiln or finding
some alternative disposal. Specifications on the waste storage, handling,
and firing problems; to prevent potential damage to process equipment; to
protect product quality; and to meet environmental restrictions. Laboratory
space, instruments, and personnel must be provided for characterizing the
waste received from shippers. Samples of each shipment need to be analyzed
to determine if wastes conform to the desired specifications. Waste not
meeting the specifications would be rejected and returned to the shipper.
Although it is possible to eliminate the need for pretreatment by a
judicious choice of specifications, to do so would severely limit the quan-
tity of waste that could be fired in furnaces. An approach that is frequent-
ly used by furnace operators is to accept only those wastes that can be up-
graded to fuel quality by one or more of the following simple, inexpensive
pretreatment processes: wast 3 blending, solids removal by inline straining,
and thermal trea^.rent. More expensive pretreatment is avoided by requiring
that wastes meet established specifications or waste properties. The waste
properties which affect furnace operation are those on whicn decisions re-
garding pretreatment are required. These properties include heating value,
solids content, water content, ash, halogen, and sulfur content, and aiet<-ls
and toxic substances (e.g., PCBs ) content.
A minimum heating value of SOOO to 8000 Btu/lb or greater is commonly
used as a guide to define whether a waste stream is being incinerated or recy-
cled for heat recover. When wastes are below this range, they can be blended
with streams bearing higher values. Since the blending would be done batch-
wise, process equipment required would consist of an agitated tank and trans-
fer pumps. Waste would be conveyed from a shipping vehicle into the agitated
tank where it would be blended with waste of higher heating value. After the
heating value of the blended waste is adjusted, it would be transferred to an
appropriate storage tank or fed directly to the furnace.
Water in a liquid waste impacts a furnace in two ways. Free or undis-
solved water in a waste stream generally causes furnce burner pulsation and
frequently leads to flame failure. Water also to-ds to lower the heating
value of the organic fraction since a portion of the heat generated by its
4-49
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combustion is consumed in vaporizing and heating the moisture to the furnace
discharge temperature. Water removal is generally not practiced at furnace
operations because the problems and costs associated with disposing of the
generated contaminated water makes limiting the war=r content of waste more
attractive. Most orsment, lime, and aggregate plants do not have wastewater
treatment facilities and ".hose with treatment systems are limited in capacity
(used mainly for treating scrubber water). A practical alternative to water
removal is to develop specifications that would disallow any free water and
limit dissolved water to less than 10% by volume. If a shipment of waste is
received which contains water in excess of the specification, it may be re-
jected. Alternatively, it may be possible to blend it with another shipment
or with waste stored on-site to meet the specification if the water concent
is not too high and the materials are compatible. Samples of the blended
waste would be analyzed to ensure that the blended mixture met the water
content specifications before it would be transferred to a storage taak or
directly to the furnace burner.
High solids concentration in liquid wastes will increase the apparent
viscosity; cause blockage of the burner nozzles; settle in waste solvent
linej; and may (if not combustible and not incorporated in the product) in-
crease particle loading to the air pollution control system. To minimize
taese problems strainers should be installed in the piping system and speci-
fications should be adopted that require that the wastes be pumpable and that
particle size be smaller than the strainer screen opening. In-line strainers
consist of one or more mesh screen baskets housed in a vessel which may be one
of a variety of geometric configurations. When the waste is passed through
the strainer, the solid particles ar« trapped in the basket. Waste solvents
often contain grit and debris such as o-rings, metal shavings, etc., that can
damage pumps or plug burner nozzles. These can easily be removed by strainers.
A 1/8-inch opening screen basket is well suited for removing such grit and de-
bris. A 100 mash screen is recommended for removing smaller particles which
might plug a burner nozzle. Several strainer designs are commercially avail-
able differing mainly in the cleaning approach. A good choice fur this appli-
cation is a duplex strainer which permits the cleaning of one basket while
another is on-line. It should be recognized that the strainer is not intended
to remove large quantities of solid?. Its purpose is to protect pumps and
prevent plugging of small restriction? in the fuel train such as burner noz-
zles. As long as the waste is pumpable, however, solids removal should not
be required. Puapability of a waste containing a high solids content may be
improved by blending the waste in the sane manner as described above for in-
creasing the heating value.
Halogens such as chlorine, bromine, iodine, etc., are commonly found
in the raw materials used to produce cement and lime clinker and pig iron.
They preferentially react with the alkali metals during production giving
volatile ha 1 ides at the higher furnace temperr.tures. As a result/ very lit-
tle halogens are found in i\ost cement and lime clinkers and iron. The al-
kali halides are usually carried from these furnace in the gas stream. For
this reason, additional chlorine is sometimes introduced with the cement kiln
feed in order to reduce clinker alkali content. The potential benefits and
problems associated with burning halogenated wastes in cement and lime kilns
were discussed earlier in this document. The raw materials used in aggregate
(lightweight and asphaltic concrete) production are not as alkaline and con-
tain much less halogens than those for pig iron, cement, and lime (Reference
4-50
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8) and the capacity of the aggregate product for forming alkali halides is
much less than that for pig iron, cement, and lime clinker. As a result,
the likelihood that chlorine will exit the furnace as HC1 is much greater for
aggregate (lightweight and asphal^-c concrete) production. This can have a
major impact on the air pollution control systems for these rurnaces es most
are susceptible to HC1 corrosion.
The most practical means of protecting process equipment and product
quality against the deleterious effects of high halogen content is to estab-
lish limits on the levels that will be accepted. Choice of a suitable limit
will be, to some degree, dependent on the type of process used for making the
product. If suitable equipment is available, waste may be blended to meet
the specification. This would greatly increase the quantity of wastes that
could be accepted for burning. A simple blending arrangement like that des-
cribed above for increasing the heating value of waste may be used.
Viscosity is important to waste firing in two regards. A primary con-
cern is that the waste be pumpable. Reasonable pump designs and piping pres-
sure drops require limitations of waste fuel viscosity at about 10,000 stan-
dard sayboIt units. Also, if the viscosity of the waste fired is too high,
it will not be possible to atomize the liquid into droplets small enough to
oxidize completely. Good atomization can usually be achieved if waste fuel
at the burner is less than 750 standard saybolt units (Reference 20). This
figure is only a qeneralization as some can handle more viscous fluids white
others cannot hai.cle liquid approaching this viscosity. If wastes must be
pumpable to b» adapted for burning, viscosity related problems can be satis-
factorily handled oy keeping the waste heated, by blending with other wast.-.-.
or a combination of the two. Viscosity can be reduced by heating the was-;e
with tarut coils or in-line heaters. However, 400° to 500°F is the normal
limit for heating to rtd-.'.co viscosity since pumping a hot tar or similar
material becomes difficult above these temperatures. Prior to heating a
liquid waste stream, a check should be made to ensure that undesirable re-
actions such as polymerization, nitration, oxidation, etc., will not occur.
If preheating is not feasible based on these considerations, a miscible li-
quid of lower viscosity may be added to reduce the viscosity in a simple
blending tank like that described above for heating value adjustment.
Where viscous materials are to be burned, provisions for both thermal
treatment and blending to regulate the viscosity may be necessary. Storage
tanks will be insulated with a two- or three-inch layer of suitable insula-
tion and heated with a side-mounted steam or electric heat exchanger, or
steam coils installed near the floor. A gear pump designed for expected
temperature and viscosity is recommended to transfer the waste fuel. The
pump and piping should be insulated and heat traced to prevent the waste
from cooling in the lines.
Hazardous waste also often contains various levels of ash, sulfur, toxic
substances such as PCB, and heavy metals such as lead, cadmium, mercury, etc.
The atmospheric discharge of some of these materials is generally limited by
local, state, or federal regulations. One regulatory approach is to restrict
the levels of these materials in the wastes being burned. Pretreating these
wastes by means other than blending to meet the imposed specifications is
considered economically impractical.
4-51
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Waste Burner
For many furnaces a burner gun must be installed to fire wastes. As pre-
viously mentioned in Section 3, pulverized coal is the primar, fuel for the
vast majority of cement, lime, and lightweight kilns. The burner for firing
this fuel is essentially an 8- to 24-iiich diameter tube which projects from 5
to 10 feet into the kiln. Pulverized coal is blown into the kiln with the
primary combustion air through this tube. Although this type of burner may
be suitable for firing some gaseous and solid wastes, it is extremely inappro-
priate for liquid wastes. Inasmuch as liquid wastes must be vaporized before
burning can take place, they must be atomized tc achieve efficient combustion.
The pulverized coal burner has no atomizing mechanism. Liquid wastes could
be sprayed onto the coal before it enters the pulverizer, but this practice
would cause significant equipment and safety problems. Thus, an atomizing
gun must be installed to fire liquid wastes in pulverized coal fueled kilns.
Although gaseous waste can be simply piped into the coal burner, generally a
center-feed gas gun is installed to give better mixing of the waste wi^h the
primary combustion air and to achieve good flame pattern control. This gun
is essentially a 1- to 2-inch diameter tube that is tapered at the firing
end. Slots are provided in the tapered end to distribute the gas in order
to enhance mixing with the combustion air. It is typically located in the
center of the coal tube. It may or may not run the full length of the coal
burner tube. It, is unlikely that gaseous wastes would be burned in a kiln,
as those wastes are typically captive waste and are burned as generated.
A gun must also be provided to fire waste in furnace equipped only with
natural gas burners. These burners cannot be used for firing liquid and
solid wastes. Although it is possible to simultaneously fire a waste gas
with natural gas through this type gun, a separate waste gun is generally
used in order to provide better flame control. Thus, a separate waste gun
is also needed for natural gas fueled kilns.
Furnaces equipped with oil guns may not require a separate gun :o fire
waste. A few furnaces employ a combination of burners: oil and gas; oil and
coal; or oil, gas, and coal. These burners may fire the fuels separately or
in combination. Typically, only one fuel (generally oil or gas) is fired at
a time and the capability of firing the other fuel(s) is maintained for stand-
by purposes if the supply of the primary fuel is temporarily unavailable. For
furnaces with oil burners, some liquid wastes may be fired using the standby
oil gun. The oil supply line is disconnected from the burner and plumbed to
the waste handling system. In order to use it for this purpose, however, the
waste viscosity, solids content, and particle size must meet the design spe-
cifications for the gun. Since the burner turndown is generally low (about
5:1) for this type of gun, its use at low feed rates may be limited due to
poor atomization. Another approach for using an existing oil gun is to blend
wastes and oil if they are compatible. This approach may be used even when
the burner is not a combination burner. However, oil is often used for start-
up purposes and furnace temperatures are low at startup. DREs of POHCs in an
oil/waste mixture would likely decline, so oil/waste mixtures should not b-2
used for startup. Where the waste canr.oc be fired in the oil gun, a separate
waste gun must be provided.
4-52
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Regardless of which gun is used, it is crucial that it be suitable for
the waste being fired and that it be operated in such a manner as not to in-
terfere significantly with the overall performance of the furnace burner. The
performance of the burner is critical to the operation of a furnace, whether
the product is cement, lime, lightweight aggregate, or any of a wide variety
of other materials. Both the furnace productivity and furnace thermal effi-
ciency in terms of heat input per unit product output are functions of the
furnace burner. Large variations in both productivity and tnermal efficiency
in the same furnace under identical conditions can be caured by changes in
the shape, length, and location of tne flaovs in the furnace. Even product
quality can be affected by these changes. Thus, the entire plant production
capacity will be affected by ihe ability of the burner to provide an optimum
flame shape, length, and location. It is, therefore, extremely important that
the firing of hazardous waste not alter this optimum flame pattern. When a
waste is fired through a gun originally installed in a furnace to burn con-
ventional fuel, the waste properties (e.g., heating value, viscosity, vola-
tility, solids content) should not differ from the conventional fuel enough
to significantly alter the flame pattern. Similarly, a burner installed for
firing a waste tc supplement the heat input provided by a conventional fuel
must be designed and located such that the flame pattern \s not altered sig-
nificantly. Also, the flame should not impinge on the furnace wall. Because
of heat radiation from the combustion zone of the furnace, an air-cooled
jacketed waste gun may be nectssary to prevent the waste froa pre-volatiliz-
ing inside the gun. When the waste/fuel ratio is large, it may be necessary
to replace the furnace burner with a combination burner to achieve a good
flame pattern.
For liquid waste, good atomization may be achieved by:
o High pressure mechanical atomization
o Low pressure air atomization
o High pressure air atomization
o High pressure steam atomization
In general, mechanical atomization of th-s waste at proper temperature and
pressure through the use of a correctly sized nozzle tip will provide com-
plete combustion and a good flame pattern. In the simplest form, the waste
is fed directly to the nozzle but turndown is limited to 2.5:1 to 3:1 since
the degree of atomization drops rapidly with decrease in pressure (Reference
20). In a modified form involving a return flow of liquid, turndown up to
10:1 can be achieved. Major disadvantages of mechanical atomization are:
o Erosion of the nozzle orifice
o Tendency to plug with solids or liquid pyrolysis products
o Potential for spraying hazardous materials over a large area in the
event of a rupture of plumbing to the gun due to the high operating
pressures
Air or steam atomization are also suitable for firing liquid hazardous
waste in a furnace. These types of atomization will likely require addition
of air or stream supplies if these are not available. Packaged systems are
available to supply these commodities. The choice of low pressure air, high
pressure air, or steam atomization will depend to a large extent on the waste
4-53
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properties and the amount of aii that can be -.olerated. Low pressure atomi-
zation can satisfactorily atomize low viscosity wastes but with a high air
requirement. Atomization air requirements vary from 370 to 1000 ft^/gallon
of waste liquid fired. This air aust be balanced with the primary combustion
air supplied with conventional fuel to maintain an optimum flame. For high
viscosity wastes, high pressure air or steam atomization, which is more ex-
pensive, is generally required.
Because of the importance of controlling the rlame pattern in a furnace,
not all types of burner guns are suitable for co-firing hazardous waste with
the conventional fuel. Equally important, some types are unacceptable be-
cause of the potential environmental risk associated with their use. The
simple tube or pipe with no atomizing nozzle is an example of an unsuitable
waste burner gun. For liquid wastes, which constitutes the major portion of
hazardous wastes fired in furnaces, good atomization is essential for complete
combustion of the waste and for good flame control. The rotary cup atomizing
gun is also not suitable for firing waste in most industrial furnaces. These
guns produce larger droplets than atomizing burners and their flam* pattern
control is poor when used over a wide range of flow.
Combustion Process Control and Safety Shutdown
In order to safely fire hazardous waste in an industrial furnace, it
may be necessary to improve the fuel combustion controls. Since there is a
variety of control instrumentation, the degree of equipment change is site-
specific. For essentially all rotary kilns used in the lightweight aggregate
industry, fuel combustion control is limited to manual adjustments of the fuel
and combustion air feed rates by an operator. Similarily, for open hearth
furnaces and many of the older ki\ns used in cement and lime production, fuel
firing is controlled manually.
In order to maintain satisfactory manual control of the fuel combustion
in the kiln, the operator u»ust observe several parameters. The flame pattern
and the color of the clinker are noted as these can indicate that the proper
combustion is being obtained. Also, the temperatures of the gases and clin-
ker are measured at various points. Gas samples are periodically withdrawn
from the kiln exhaust for determination of oxygen ard carbon monoxide levels.
Draft pressure developed by the fans moving air through the kiln, preheaters,
and/or precalciners are observed. Armed with these observations, the opera-
tor generally is able to manually control the fuel combustion to safely pro-
duce quality clinker.
Although hazardous waste may be safely fired with manual control of the
fuel and combustion air feed rates, automatic termination of waste feed is
deemed necessary to prevent the release of hazardous materials to the envi-
ronment in the event of flameout, other combustion process upsets, or air
pollution control device failure. This requires the installation of a flame
scanner. This device senses ultraviolet radiation from the flame. When the
flame is lost, the scanner signals an automatic valve in the waste feed line
to close, immediately terminating the waste to the burner. An alarm should
also be added to warn the operator of the waste fuel shut off. It is also
deemed necessary to provide continuous monitoring of carbon monoxide levels
in the furnace exhaust gases to ensure that proper air/fuel stoichiometry is
maintained to achieve adequate combustion of the hazardous waste. An oxygen
4-54
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analyzer is also necessary to correct the carbon monoxide readings for dilu-
tion by air inleakage into the flue gases. A carbon monoxide analyzer linked
to an automatic waste field shut-off system could quickly terminate waste feed
in the event that poor combustion conditions cannot be eliminated by equipment
adjustments. Additional discussion of rxygen and carbon dioxide monitoring
is contained in a later subsection.
Because of the ever increasing cost of energy, industrial furnaces con-
structed in the last five years are generally equipped with semi-automatic
process controls which incorporate logic and instrumentation for managing
fuel combustion. These systems vary considerably in capability with the more
sophisticated ones including metering of the fuel(s) and automatic adjustment
of fuel:air ratio using continuous oxygen and/or carbon monoxide monitoring.
The controls may be set up to control single fuel or multiple fuel firing.
They ara usually based on known heating values or air:fuel ratio requirements
for each fuel.
The extent to which the semi-automatic control systems must be modified
to fire hazardous waste depends on the system design and desired control op-
tions. If a waste is to be co-fired with a conventional fuel and is to be
restricted to less than about 25% of the total heat input, metering of waste
fuel into the furnace by the process controls is not needed. The furnace
could be manually baseloaded on the waste fuel with the process controls be-
ing used to manage process savings by adjusting the conventional fuel and
combustion air flows. This would require no significant change in the com-
bustion controls. Similarly, if the system is designed for multiple fuel
firing, the required changes may be as minor as reprogramming the micropro-
cessor to account for the heating value different between the waste to be
fired and the fuel being replaced by the waste.
Significant changes to a furnace's combustion controls may be needed
when independent modulation of the waste and conventional fuel feed rate is
required. Two such waste/fuel burning configurations are identifiable. In-
dependent modulation is needed to fire either 100% waste fuel or 100% conven-
tional fuel when the properties of the waste are very different from those
of the conventional fuel, e.g., liquid waste and pulverized coal. Similarly,
co-firing at more than 25% of the total heat input with a conventional fuel
would require considerable changes to the control instrumentation. Both these
options necessitate additional flow control valves and may require a new mi-
croprocessor. An automatic flame supervision system is considered essential
whenever one is not included as part of the combustion control instrumenta-
tion.
Waste Feed Rate Monitoring
It may be necessary to restrict the flow of some highly toxic waste
streams to a small fraction of the total fuel input to ensure adequate de-
struction of a ?OHC. If such restrictions are adopted, waste feed rate mon-
itoring will be needed. Additionally, a trial burn may be required to demon-
strate the capability of a furnace to achieve an adopted ORE. The quantity
of POHC being fed to the furnace is needed for the ORE determination. Where
metering pumps or feeders are employed to convey the waste to the burner, a
continuous measurement of the feed rate may be obtained by modifying these
devices to provide a rate-dependent signal to some type of recording device.
4-55
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The following paragraphs some of the r.ore useful flow meters that may be used
for this application. Detaile^ information on these and other flow meters
con be found in References 21 through 24.
There is no universally applicable flow meter. The proper selection de-
pends on the waste properties, acceptable pressure drop, required accuracy,
and flow range to be measured. It is critical that the operation of the flow
meter be compatible with the waste. Properties of chief concern in th.'.s re-
gard include physical state, viscosity, solids content, electrical conducti-
vity, and corrosivity. Pressure loss is an important consideration in that
energy must be expended to overcome it. The flow meter must also be capable
of measuring the flow to the specific accuracy over the flow range which it
is used.
The crifice meter, the positive-displacement meter, the flow tube meter,
the vortex shedding meter, and the turbine meter cover a wide range of ap-
plications for liquid and gaseous hazardous wastes. These instruments are
moderately inexpensive, are capable of the needed accuracy, are of relative
simple design, and can be used over a large range of flows. The orifice me-
ter and flow tube are differential pressure type flow measurement devices.
This type directly measures fluid velocity by measuring a differential head
(pressure) across an obstruction in the flow stream which increases the velo-
city of the fluid, thereby decreasing its pressure. Flow equations relate
the velocity change to the pressure change. In an orifice meter, the differ-
ential pressure between the upstream and downstream sides of an orifice plate
is measured with pressure taps on either side of the orifice plate.
One disadvantage of the orifice meter for use in this application is that
suspended matter in the fluid may build up at the inside of the orifice plate
and affect its accuracy. This can be avoided by keeping the solids content
low. If it is not practical to reduce the solids content, the flow tube may
be used. The flow tube is basically a venturi without the downstream recovery
cone. Because it does not restrict the flow to the extent an orifice elate
does, it is applicable to streams with appreciable solids content. It nas a
very constant discharge coefficient and is considered i-.o be highly reliable.
It is not as expensive as the venturi but considerably more expensive than
the orifice meter.
The positive-displacement flow meters have one or more moving parts posi-
tioned in the flow stream. The main devices are reciprocatory piston, rotary
piston, rotary-vane meter, and nutating disk. Of these, more nutating disk me-
ters are probably used in than all the others combined. This device consists
of a movable disk mounted on a concentric sphere. The disk is contained in a
working chamber with spherical sidewalls and top and bottom surfaces that ex-
tend conically inward. The disk is restricted from rotating about its own ax-
is by a radial partition that extends across the entire height of the working
chamber. Each complete movement of the disk displaces a fixed volume of li-
quid. The liquid enters through an inlet port and fills the spaces above and
below the disk, which fits closely and precisely in the measuring chamber.
The advancing volume of liquid moves the piston in a nutating motion until the
liquid discharges from the output port. The major limitation of this type of
flow meter is its sensitivity to grit.
4-56
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With a vortex shedding meter, the fluid stream is forced past an obstruc-
tion (shedding bar) which sets up vortices (eddies) in the fluid. These vor-
tices cause vibrations in the shedding bar which are proportional to the flow.
A piezoelectric crystal converts these vibrations to a voltage that is ampli-
fied and transmitted to an electronic scaling iaociule. Advantages of these
instruments include accuracy, no moving parts, and relatively low price.
The turbine meter is a mechanical-type measurement instrument. It oper-
ates on the turbine principle, i.e., the volume is measured by the movement
of a wheel or turbine type of impeller. The blades of the turbine, which are
positioned within a chamber, rotate as the fluid passes through them. The
rotor can be positioned so that it can be driven by radial or axial flow or
a combination of both. The rotor's motion can directly drive a register.
This device can be used to measure continuous high gas flow rates with mini-
mum pressure loss. It is not well suited for liquids containing appreciable
quantities of solids.
Oxygen and Carbon Monoxide Monitoring
The test results presented earlier in this section demonstrated that fur-
naces used in cement, lime, and aggregate production are capable of a 99.99%
ORE. However, good combustion conditions must be maintained to ensure high
ORES. Like all combustion devices, industrial furnaces are subject to operat-
ing excursions. An acceptable DR£ must be maintained during these excursions
to prevent the emissions of hazardous materials to the environment or else
the waste feed must be shut off. Continuous monitoring of ORE is impractical
because of the complexity (and cost) of the sampling and analysis required.
Consequently, some surrogate indicator of the combustion perfornance is needed.
Combustion performance depends on operating parameters such as temperature,
feed rate of waste, and air flow rate, but monitoring these operating param-
eters does not indicate what is actually being accomplished in the furnace in
terms of the waste destruction.
Monitoring oxygen and/or carbon monoxide levels in the flue gases does
give a continuous assessment of the effectiveness of combustion. (For fur-
naces intentionally operated under reducing conditions, such as a blast fur-
nace, CO monitoring as a surrogate indicator of waste combustion performance
is not practical. However, the off-gases from reducing furnaces are typically
burned in other combustion devices where CO monitoring as a surrogate indica-
tor of combustion performance is practical). Generally accepted combustion
theory holds that low CO (carbon monoxide) flue gas levels are indicative of
a furnace operating at maximum combustion efficiency. Operating at maximum
combustion conditions ensures minimum emissions of unburned (or incompletely
burned) organics. In the first stage of combustion of hazardous waste fuel,
the POHCs are immediately thermally decomposed in the flame to form other,
usually smaller, compounds termed PICs. In this first stage of combustion
these PICs are also rapidly decomposed to form CO.
The second stage of combustion involves the oxidation of CO to C02 (car-
bon dioxide). The CO to CO2 step is the slowest (rate controlling) step in
the combustion process because CO is considered to be more thermally stable
(difficult to oxidize) than other intermediate products of combustion of haz-
ardous waste constituents. Since fuel is continuously being fired, both com-
bustion stages are occurring simultaneously.
4-57
-------
Using this view of waste combustion, the "destruction" of a POHC, and
perhaps even the destruction of PI.Cs, is independent of flue gas CO levels.
Thus, CO flue gas levels cannot be correlated to ORE for POHCs and may not
correlate well with PIC destruction. Low CO is an indicator of the status of
the CO to CO2 conversion process, the last, rate-limiting oxidation process.
Since oxidation of CO to CO^ occurs after destruction of the POHC and its
(other) intermediate (PICs), the absence of CO is a useful indication of POHC
and PIC destruction. The presence of high levels of CO in the flue gas is a
useful indication of inefficient combustion, and at some level of elevated
CO flue gas concentrations, an indication of failure of the PIC and POHC de-
struction process.
Instrumentation for both 02 and CO monitoring of furnace flue gas is com-
mercially available, is considered to be reliable, and is already installed
on some industrial furnaces for combustion control. A variety of analyzers
are used in these monitoring systems. These are reviewed in Reference 25
which also presents a list of vendors.
Although the analyzers could be used to manually shut-off waste feed, an
automatic shut-off system consisting of a microprocessor-controlled shut-off
valve is deemed more appropriate. The microprocessor could time-average the
signals from the analyzers and signal the valves to stop the waste feed if a
time-averaged CO limit is exceeded.
Air Pollution Control Equipment
All industrial furnaces are eventually are vented through some type of
dust collection systems to control particle emissions. The efficiency of
these systems was discussed in Section 3. Two important considerations in
the RIA of firing hazardous wastes are:
o How must these dust collection systems be modified so that hazardous
waste can be fired without violating existing emission standards?
o What further modifications may be required when RCRA regulation of
hazardous waste firing in industrial furnaces is promulgated?
In order to answer the first question, an understanding is needed of the
potential impact cf firing hazardous waste on the furnace air emissions. This
potential impact is directly related to the following waste constituents: ash,
sulfur, trace metals, toxic substances (e.g., PCB), and halogens. These spe-
cies exit the furnace as part of product, the waste solids and liquids, and/or
in the exhaust gases. Any fuel conversion could increase the particle loading
beyond the capacity of collection systems. This is not likely to occur with
furnaces firing coal as waste fuels typically contain less ash than the 5 to
20% ash coal they replace. A waste with enough noncombustible material to
create a particle emission increase for coal-fired furnace would create in-
tolerable storage, pumping, and combustion problems.
As with conventional fuels, some of the sulfur in the hazardous waste
fuel will exit the furnace in the exhaust gases as sulfur dioxide. The dust
collection systems on most furnaces are not very effective for FGD (spent
acid recovery furnaces are inherently equipped for SO2 control). When burn-
ing conventional fuels, furnace operators find it more economical to use low
4-58
-------
sulfur fuels than to install FGD. This being the case, there is little like-
lihood taat high sulfur waste fuels will be accepted for incineration at a
all but spent recovery furnaces. Economics simply make it more practical to
limit the waste sulfur content than to upgrade the existing dust collection
system to provide for FGD.
Trace metal removal efficiencies of most furnaces dust collection sys-
tems have not been established. Because of the potential risk to the health
of the population surrounding a furnace, a maximum allowable concentration of
some of these metals in waste fuel could be established. This approach would
eliminate the need to evaluate and possibly upgrade existing control systems
to ensure that the public's health is adequately protected from exposure to
atmospheric emissions of toxic metals.
Toxic substances like PCS, homicides, and pesticides are generally lim-
iteci to such low concentrations in the waste fuel by existing regulations
that the need for further reduction by air pollution control equipment is
impractical and unwarranted.
Firing halogenated wastes impact emissions in the following ways:
o For cement and lime kilns and other furnaces which process alkaline
raw material, it can change the resistivity of the dust and increase
the exhaust dust loading if ESPs are used.
o It substantially increases the HC1 emissions from furnaces not pro-
cessing alkaline raw materials which neutralize tha HC1 produced
during combustion. These increased HC1 emissions which can rapidly
corrode the equipment used for controlling particle emissions from
these furnaces.
The halogens released when halogenated wastes are broken into their consti-
tuent elements form volatile alkali halides in the cement and lime kilns and
other furnaces processing alkaline materials. Some of the alkali halides,
principally those formed from potassium (and possibly sodium), exit the fur-
nace as gaseous fumes and later condense to dusts at the lower temperatures
outside the furnace. This increases the dust loading to the control equip-
ment. While the increased dust loading experienced by the dust collection
system can result in increased particle emissions, it is quite feasible that
the process and/or air pollution equipment operating conditions can be modi-
fied to adequately control emissions. Proceis changes, which can probably
be employed, include reducing the insufflation rates of the recovered dust,
reducing the rates at which leached dust is recycled, altering furnace drafts,
and modifying furnace kinetics. The appropriate air pollution control device
operation change needed to counter increased loading depends on the type of
equipment being used. For an ESP, the increased loading may be offset by
increasing the rapping frequency and modifying tne voltage ar-) current dis-
tributions. A baghouse is generally insensitive to slight changes in load-
ing and increasing the cleaning frequency is one way of countering larger
dust loading- For a scrubber, the increased loading can, in some applica-
tions, be offset by increasing the pressure drop or the amount of scrubbing
water.
4-59
-------
The raw materials used in making lightweight aggregate contain substan-
tially less alkali metals than those used in making cement and lime. For this
reason, the formation of alkali halides in lightweight aggregate kilns does
r»ot take place to the extent that it does in cement and litae kilns. As a re-
sult, corrosive acids, e.g., HC1, are generated when halogenated organirs are
fired in these kilns. Furthermore, the lightweight aggregate raw materials
are not nearly as alkaline as those used in cement and lime production and
is therefore, not as capable of neutralizir generated acids. Thus, these
corrosive acids exit the kiln with the exhaust gases and enter the dust col-
lection system which is generally a wet scrubber. This can create two poten-
tial problems. If the materials of construction are not resistant to acids,
rapid corrosion will occur and the scrubber may have to be replaced. The
second potential problem is that some states may ha.-« HC1 emission limita-
tions. If emission standards cannot be achieved with the existing scrubber,
modification or replacement may be required.
4-60
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REFERENCES
1. Protocol for the Collection and Analysis of Volatile POHCs Using VOST.
U.S. Environmental Protection Ayency. EPA-600/S-94-007. March 1984.
2. Code of Federal Regulations, Title 40, Part 60. Appendix A, Reference
Method 23.
j. Lee, K-C., et al. Revised Model for the Prediction of the Tii*e-Temper-
ature Requirements for Thermal Destruction of Dilute Organic \.ipors and
Its Usage for Predicting Compound Destructability. Union Carbide Cor-
poration. South Charleston, West Virginia. Presented at the 75th An-
nual Meeting of the Air Pollution Control Association, New Orleans.
June 1982.
4. Preliminary data. Personal communication from B. Dellinger, University
of Dayton Research Institute, Dayton, Ohio to C.D. Wolbach, Acurex Cor-
poration. January 1983.
5. Duvall, D.S. and Rubey, W.A. Laboratory Evaluation of High Temperature
Destruction of Polychlorinated Biphenyls and Related Compounds. SFA-
600/2-77-228. Municipal Environmental Research Laboratory. Cincinnati,
Ohio. December 1977.
6. Engineering Evaluation Report C-82-080. Supplemental Fuels Project/Gen-
eral Portland, Inc./California Division/Los Robles Cement Plant/Lebec,
California. State of California Air Resources Board, 1983.
7. Evaluation of Waste Combustion in Cement Kilns at General Portland, Inc.,
Paulding, Ohio. Research Triangle Institute and Engineering-Science,
Inc. March 1984.
8. Day, D.R. and Cox, L.A. (Monsanto Research Corporation). Evaluation
of Hazardous Waste Incineration in an Aggregate Kiln: Florida Solite
Corporation. May 30, 1984.
9. Day, D.R. and Cox, L.A. (Monsanto Research Corporation). Evaluation
of Hazardous Waste Incineration in Lime Kilns at Rockwell Lime Company.
October 1983.
10. Smith, G.E. and Rom, J.J. (Systech Corporation). Hazardous Waste Com-
bustion in a Dry Process Cement Kiln. September 1982.
11. Evaluation of Waste Combustion in a Dry Process Cement Kiln at Lone
Star Industries, Oglesby, Illinois. Research Triangle Institute and
Engineering-Science, Inc. April 1984.
12. Peters, J.A., et al. (Monsanto Research Corporation). Evaluation of
Hazardous Waste Incineration in Cement Kilns at San Juan Cement Company.
August 1983.
13. Barta, J.P. and Nabi S. Zarr. Emissions from the Combustion of Fuel Oil
Containing Chlorinated Asphaltic Compounds. Texas Air Control Board.
4-61
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14. Harris, J.C. and Schlickenrieder, Lynn K. Waste Oil Combustion at a
Batch Asphalt Plant: Trail Burn Sampling and Analysis. Presented at
the 76th Annual Meeting of the Air Pollution Control Association. June
19-24, 1983.
15. Baker, R.*.., et al. Draft Summary Test Report: Sampling and Analysis of
Hazardous Waste and Waste Oil Burned in Three Asphalt Plants. Prepared
for U.S. Environmental Protection Agency. January 1986.
16. Destruction and Removal of POHCs in Iron Making Blast Furnaces. Prepared
by Radian Corporation for the U.S. Environmental Protection Agency. De-
cember 31, 1985.
17. McDaniels, M. (Engineering-Science). A Report on A Flare Efficiency
Study. Chemical Manufacturers Association, September 1982.
18. Pohl, J.H., et al. (Energy & Environmental Research Corporation).
Evaluation of the Efficiency of Industrial Flares: Test Results. U.S.
Environmental Protection Agency. Publication EPA-600/2-84-095. May
1984.
19. Pohl, J.H., & Soellsy, N.R. (Energy & Environmental Research Corporation).
Evaluation of the Efficiency of Industrial Flares: Flare Head Design &
Gas Composition. U.S. Environmental Protection Agency. Publication EPA-
600/2-85-106. September 1985.
20. Engineering Handbook for Hazardous Waste Incineration. U.S. Environmen-
tal Protection Agency. Washington, D.C. Publication SW 889. September
1981 .
21. Fluid Meters, Their Theory and Application, 5th Edition. American So-
ciety of Mechanical Engineers: New York, 1959.
22. Spring, L.K. Principles and Practice of Flowmeter Engineering, 9th
Edition. Plimpton Press, Norwood, Massachusetts, 1967.
23. Cheremisinoff, N.P. Applied Fluid Flow Measurement: Fundamental and
Technology. Marcel Dekker, Inc., New York, 1979.
24. Flow: Its Measurement and Control in Science and Industry. Vol. I
and II, Instrument Society of America. Research Triangle Park, North
Carolina. 1971, 1982.
25. Continuous Air Pollution Source Monitoring Handbook. U.S. Environmental
Protection Agency, Cincinnati, Ohio, EPA-825/6-79-005. June 1979.
4-62
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SECTION 5
COST ELEMENTS FOR THE REGULATOR* IMPACT ANALYSIS
GENERAL
A key element of any regulatory impact analysis is an assessment of the
potential economic impact of the various regulatory options* bei'.ig considered.
This section identifies the major cost 'actors being considered by EFA in the
assessment and provides selective cost data that are not being obtained by
EFA from other sources. Regulations for the burning of hazardous waster as
hazardous waste derived fuels (HWDF) in industrial furnaces could potentially
have an economic impact on waste producers, furnace operators, and regulatory
agencies. This report is limited to those costs associated with burning the
wastes in existing industrial furnaces. The actual economic impact analysis
will be presented by EFA in a separate document.
The economic impact of burning hazardous waste in industrial furnaces
is being analyzed by EPA in terms of how the various regulatory options alter
the net fuel savings. This net savings is the difference between the credits
associated with the fuel replacement and the increased capital and operating
costs of firing waste over firing conventional fuels. Therefore, analysis
of the economic impact of a regulatory option requires cost data for the sig-
nificant elements of the credits and the incremental costs. The choice of
cost elements will depend, to a large extent, on the level of detail speci-
fiad of the analysis. These data are being obtained from a number of sources•
The items being provided in this document fall into three major categories:
(1) conventional fuel prices, (2) capital costs to modify the furnace sy tern
to burn a hazardous waste derived fuel (HWDF), and (3) the major operating
and maintenance (O&M) costs associated with burning a HWDF.
The costs are presented so that they may easily be applied by EPA in its
analysis as they are needed for each specific industrial furnace.
CONVENTIONAL FUEL PRICES
The prices of conventional fuels for industrial furnaces are to be used
in the analysis of fuel replacement credits. Two sets of prices are consi-
dered. The first set is for 1982 which was the year covered by the OSW Burn-
er Questionnaire survey of waste fuel users. The results of this survey will
also be used in the economic impact analysis. The 1982 prices were:
5-1
-------
o Naturai Gas - $3.63 per million Btu
o Distillate Oil - $7.24 per million Btu
o Residual Oil - $4.62 per million Btu
o Cca} - $1.09 per million Btu
The above 1982 fuel prices were ootained from documents published by
the Energy Information Administration which is the brancn of the Department
01 Energy responsible for collecting, compiling, and disseminating data on
Uniteu States energy cost and usage. Natural gas and oil prices were devel-
oped from data provided in Reference 1; coal prices were based on data fiom
Reference 2. These prices were representative of the national average values
paid by industrial users in 1982.
One element of the RIA is to estimate the impact of the regulation on
future HWDF burner operations. Therefore, a second fuel data set was needed;
projected fuel prices for the period covered by the analysis. Fuel prices
projected for the period 1985 through 2010, are listed in Tables 5.1 through
5.4. These projections were taken from Reference 3 currently being used by
the EPA Office of Air Quality Planning and Standards (OA^PS) for its econom-
ical modeling as part of its effort to develop New Source Performance Stan-
dards (NSPS) for industrial boilers. Costs are updated periodically.
CAPITAL COSTS
When fossil iuel-fired furnaces are used to burn hazardous wastes,
capital expenditures may be required for a number of system modifications,
including: waste characterization and pretreatment, storage and handling
facilities; fuel burners; combustion control instrumentation; waste feed
metering; combustion gas oxygen and carbon monoxide monitoring; and air
pollution controls for toxic metals and HC1 emissions.
Cost data for waste storage and handling facilities have been generated
by EPA for its economic analysis of treatment, storage and disposal facili-
ties. Therefore, cost data for waste storage and handling are not presented
here. Cost data for the remaining elements have been aggregated into three
groups.
o Waste characterization and pretreatment costs
o Furnace modifications costs
' Air pollution control device costs
The cost data presented below were developed from published data, vendor in-
formation, and engineering judgment. The following discussion includes the
various elements comprising these three groups.
Waste Characterization and Pretreatment Costs
A combination of restrictions on waste characteristics and pretreatment
of wastes is needed in order to avoid potential adverse impacts of firing
hazardous waste on furnace equipment, product qual:'. "v, and the environment.
The potential problems of firing these wastes could >- avoided merely by ad-
hering to a stringent acceptance specification. Alternatively, one could ac-
cept wastes of unrestricted quality and depend on pretreatment to make them
5-2
-------
TABLE 5.1
PROJECTIONS OF REGIONAL INDUSTRIAL NATURAL GAS PRICES3
(1982 dollars per million Btu)
Denand Region 1985 1990 1995 2000 2005 2010
1. t:«w England 6.09 7.16 8.50 11.47 14.67 16.50
2. New York/New Jersey 4.90 5,-il 6.42 8.67 11.09 12.47
3. Middle Atlantic 4.29 4.. • 5.45 7.35 9,40 10.57
4. South Atlantic 4.82 5.70 6.76 9.13 11.67 13.13
5. Midwest 4.14 4.90 5.81 7.85 10.03 11.29
6. Southwest 4.27 4.63 5.50 7.42 9.49 10.67
7. Central 3.77 4.55 5.40 7.30 9.33 10.49
8. North Central 4.22 4.79 5.68 7.67 9.81 11.04
9. West 4.69 5.44 6.45 8.71 11.14 12.53
10. Northwest 4.90 5.08 6.03 8.15 10.41 11.72
a Taken from Reference 3.
5-3
-------
TABLE 5.2
PROJECTIONS OF REGIONAL INDUSTRIAL REJ'^DUAL FUEL OIL PRICESa'b
Cl.yB2 dollars per million Btu)
1 .
2.
3.
4.
5.
6.
7.
8.
9.
10.
Demand Region
New England
New York /New Jersey
Middle Atlantic
South Atlantic
Midwest
Southwest
Central
North Central
West
Northwest
1985
4.
4.
4.
4.
4.
4.
4.
4.
4.
4,
09
02
01
20
34
43
40
25
49
31
1990
5.15
5.09
5.09
5.32
5.44
5.63
5.51
5.40
5.71
5.49
1995
7.
7.
7.
7.
7.
8.
7.
7.
8.
7.
32
23
22
56
73
00
83
67
10
79
2000
8.
8.
8.
9.
9.
9.
9.
9.
9.
9.
92
82
81
21
42
75
54
35
88
50
2005
11
10
10
1 1
11
12
1 1
1 1
12
11
.11
.98
.97
.48
.73
.14
.89
.65
.31
.84
2010
12.78
12.63
12.62
13.20
13.50
13.97
13.67
13.40
14.16
13.62
a 1.6% sulfur.
0.3% sulfur * 1.6% sulfur + $0.68/MMBtu.
0.8% sulfur - 1.6% sulfur + $0.35/MMBtu.
3.0% sulfur - 1.6% sulfur - $0.45/MMBtu.
b Taken from Reference 3.
5-4
-------
TABLE 5.3
PROJECTIONS OF REGIONAL INDUSTRIAL DISTILLATE FUEL OIL PRICES3
(1982 dollars per million Btu)
Demand Region 1985 1990 1 99b 2000 2005 2010
1. New Enyland 6.33 7.28 10.02 12.07 14.84 16.96
2. New York/New Jersey 6.27 7.22 9.93 11.97 14.71 '6.82
3. Middle Atlantic 6.24 7.18 9.88 11.90 14.63 16.72
4. South Atlantic 6.08 7.03 9.68 11.66 14.34 16.39
5. Midwest 6.20 7.13 9.82 11.83 14.54* 16.62
6. Southwest 6.08 7.06 9.72 11.71 14.40 16.45
7. Central 6.15 7.08 9.74 11.73 14.42 16.49
8. North Central 5.98 6.94 9.55 11.50 14.14 16.16
9. West 6.04 7.01 S.65 11.63 14.29 16.34
10. Northwest 6.04 7.01 9.65 11.63 14.29 16.34
a Taken from Reference 3.
5-5
-------
TABLE 5.4
PROJECTIONS OF REGIONAL DELIVERED INDUSTRIAL COAL PRICESa'b
(January 1983 dollars oer million Btu)
1.
2.
3.
4.
5.
Sulfur Content
Demand Region Coal Type ( Ib SO^/MKBtu)
New England Bituminous <0.80
0.80 - 1.08
1.08 - 1.67
1.67 - 2.50
2.50 - 3.33
3.33 - 5.00
>5.00
New York/New Jersey Bituminous <0.80
0.80 - 1.08
1.08 - 1.67
1.67 - 2.50
2.50 - 3.33
3.33 - 5.00
>5.00
Middle Atlantic Bituminous <0.80
0.80 - 1.08
1.08 - 1.67
1.67 - 2.50
2.50 - 3.33
3.33 - 5.00
>5.00
South Atlantic Bituminous <0.80
0.80 - 1.08
1.08 - 1.67
1.6-* - 2.50
2.50 - 3.33
3.33 - 5.00
>5.00
Midwest Bituminous <0.80
0.80 - 1.08
1.08 - 1.67
1.67 - 2.50
2.50 - 3.33
3.33 - 5.00
>5.00
Sub- <0.80
Bituminous O.SO - 1.08
1985
3.33
3.42
3.30
3.25
3.19
2.68
2.94
3.34
3.20
3.10
2.94
2.87
2.39
2.60
2. S3
2.77
2.60
2..;o
2.41
1.98
1.77
2.92
2.74
2.55
2.30
2.64
2.09
2.52
3.13
2.94
3.00
2.70
2.59
2.18
2.23
2.63
2.63
1990
3.77
3.67
3.67
3.68
3.50
3.98
3.21
3.52
3.41
3.42
3.22
3.14
2.71
2.83
3.20
3.05
2.96
2.74
2.70
2.50
2.14
3.32
3.12
2.60
2.80
2.53
2.69
2.64
3.39
3.22
3.14
2.97
2.91
2.46
2.42
2.84
2.84
1995
3.93
3.80
3.88
3.85
3.64
3.29
3.41
3.62
3.51
3.54
3.35
3.22
2.90
2.97
3.34
3.17
3.11
2.88
2.82
2.81
2.32
3.47
3.26
3.03
3.06
2.55
2.81
2.71
3.53
3.37
3.30
3.08
3.02
2.78
2.52
2.84
2.84
2000
4.01
3.92
4.03
3.96
3.68
3.48
3.56
3.74
3.63
3.66
3.47
3.31
3.14
3.13
3.45
3.30
3.25
3.00
3.04
2.96
2.54
3.66
3.42
3.31
3.17
2.70
2.96
2.87
3.66
3.48
3.45
3.21
3.14
2.91
2.67
2.92
2.92
5-6
-------
TABLE 5.4—Continued
Sulfur
Content
Demand Region Coal Type ( Ib SO^/MMBtu) 1985
6. Southwest Bituminous
0
1
1
2
3
7. Central Bituminous
0
1
1
2
3
Sub-Bi tumi nous
0
1
1
8. North Central Bituminous
0
1
1
Sub-Bi tumi nous
0
1
1
9. West Bituminous
0
1
1
Sub-Bituminous 1
1 0. Northwest Bituminous
0
1
1
Sub-Bi tuminous
0
1
1
<0
.80
.08
.67
.50
.33
>5
.80
- 1
- 1
- 2
- 3
- 5
.00
.08
.67
.50
.33
.00
<0.80
.80
.08
.67
.50
.33
>5
<0
.80
.08
.67
- 1
- 1
- 2
- 3
- 5
.00
.80
- 1
— 1
- 2
.08
.67
.50
.33
.00
.08
.67
.50
<0.80
.80
.08
.67
<0
.80
.08
.67
<0
.80
.08
.67
.67
<0
.80
.08
.67
<0
.80
.08
.67
- 1
- 1
- 2
.80
- 1
- 1
- 2
.80
- 1
- 1
- 2
- 2
.80
- 1
- 1
- 2
.80
- 1
- 1
- 2
.08
,67
.50
.08
.67
.50
.08
.67
.50
.50
.08
.67
.50
.08
.67
.50
* By ZCP Inc., 1850 K Street, N.W., Washington,
b Taken from Reference 3.
2
2
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
1
1
1
1
1
1
0
0
2
2
2
2
2
3
3
2
2
2
2
2
2
D.C.
.94
.89
.03
.71
.57
.95
.32
.77
.76
.95
.95
.94
.69
•34
.53
.53
.37
.43
.64
.47
.29
.91
.52
.36
.86
.80
.69
.63
.26
.53
.34
.18
.10
.17
.80
.06
.06
.05
.05
1990
3
3
2
3
2
3
2
2
2
3
3
3
2
2
2
2
2
2
1
1
1
1
1
1
0
0
2
2
2
2
2
3
3
2
2
2
2
2
2
.31
.26
.65
.09
.79
.17
.84
.97
.95
.23
.22
.15
.61
.47
.60
.60
.44
.48
.87
.66
.34
.40
.62
.48
.92
.90
.87
.76
.49
.78
.42
.37
.24
.27
.81
.14
.14
.10
.05
1995
3
3
3
3
2
3
2
3
3
3
3
3
2
2
2
2
2
2
1
1
1
1
1
1
1
1
2
2
2
2
2
3
3
3
2
2
2
2
2
.58
.51
.02
.19
.94
,39
.97
.09
.07
.34
.18
.27
.58
.52
.72
.72
.52
.63
.92
.74
.35
.50
.59
.47
.01
.04
.91
.82
.85
.60
.49
.42
.30
.29
.78
.29
.29
.29
.05
2000
3
3
3
3
3
3
3
3
3
3
3
3
2
2
2
2
2
2
2
1
1
1
1
1
1
1
3
2
2
2
2
3
3
3
2
2
2
2
2
.77
.69
.16
.21
.08
.46
.07
.14
.09
.46
.22
.40
.66
.58
.81
.81
.81
.54
.01
.76
.38
.54
.75
.59
.12
.06
.15
.98
.91
.65
.59
.58
.42
.42
.80
.36
.36
.36
.10
, 20006.
5-7
-------
suitable for furnace firing. Depending solely on waste specifications would
severely limit the quantity of acceptable waste. Conversely, depending sole-
ly on pretreatment is not technically and/or economically practical for many
wastes. Therefore, the a»ore practical approach for preventing waste-fuel
burning related problems in industrial furnaces is a combination of waste
restriction and inexpensive pretreatment processes (blending, straining of
grit and debris, and thermal treatment).
Operational and tixicity related problems can be prevented by establish-
ing limits on waste characteristics that significantly influence furnace equip-
ment deterioration, product quality, and/or the environmental risk related to
firing wastes. These characteristics include heating value, water content,
solids content, halogen content, viscosity, ash, toxic substances such as PCB
and metals. Limits on these characteristics could be used as criteria for
accepting or rejecting waste from shippers or other plant operations. Each
waste shipment would be analyzed to determine its acceptability as a fuel.
Wastes and/or HWDF which could meet the specifications as received or after
blending, in-line straining, and/or thermal treatment would be accepted for
burning while those out-of-specification wastes would be rejected. Blending
with either a conventional fuel or another compatible waste or HWDF would be
used when possible to upgrade it to an acceptable quality, i.e., to reduce
the concentration of metals, ash, sulfur, solids, water, or halogens, and/or
to increase the heating value of wastes. In-line strainers would be used to
remove grit and other large particles to protect pumps and to prevent plug-
ging of the burner gun. Viscous wastes would be heated to make them pumpable
and to permit proper atomization necessary for high combustion efficiency.
The cost to characterize and/or pretreat a waste to make it suitable for
furnace firing offsets the money saved in fuel replacement. This section pre-
sents these offsetting costs which are required for an economic analysis of
waste firing in industrial furnaces.
Waste Characterization
The use of waste specifications as criteria for eliminating unsuitable
wastes requires characterization of the physical and chemical properties.
Therefore, provisions must be made for the necessary analyses. Throe ap-
proaches for obtaining the analyses are possible. One approach would be to
perform all analyses on-site, which would require the acquisition of analy-
tical equipment. Laboratory space for the needed equipment could generally
be made available in an existing laboratory or by converting office space.
Another option would entail using a commercial laboratory for the required
analyses. A third approach, is to perform some of the simple analyses in
the' plant laboratory while contracting a commercial laboratory for the more
sophisticated analyses. The third approach was used to prepare analytical
costs. It was assumed that analyses for metals and toxic substances would
be made by a commercial laboratory while the other analyses would be con-
ducted in a plant laboratory. Sufficient plant laboratory space to conduct
the simple analyses was estimated to cost approximately $50,000. Equipment
for determining compatibility, heating value, halogen content, sulfur, ash,
water content, and specific gravity could be purchased for approximately
$25,000. Costs for having the analyses made by a commercial laboratory are
estimated later in this section along with other waste firing related O&H
costs.
5-8
-------
Blending
Blending a waste with a conventional fuel or another higher Btu waste
provides an inexpensive means of reducing the concentration of metals, ash,
sulfur, solids, water, or halogens, while increasing its heating value for
safe disposal in an industrial furnace. Blending wastes is gen-arally a
batch process. Grab samples taken from each waste lot are used to confirm
that they can be upgraded to the established specifications by blending.
The selected waste batch is transferred to the blend tank where it is mixed
with anociier waste or fuel oil. Samples of the materials to be blended are
tested for compatibility before mixing. After the materials are mixed, the
blended waste is either pumped into a Larger tank for storage or directly
to the furnace burner(s).
The equipment should be designed to process wastes received from off-
site as weil as from other plant operations. A simple system would consist
of an agitation tank plus pumps and j iping. At mini-num, it would use a
20,000 gallon t^nk which is large enough to hold a tank truck load (5,000-
10,000 gallons) plus the higher quality blend stock. A typical blending
operation might operate one shift p« r day for five days per week, blending
20,000 gallons per shift. This schedule is especially suited to plan' s that
only run one shift: per day such as asphalt concrete plants. The blenching
schedule includes time for sampline and analysis, transferring it to the
blend tank, adding high quality material, mixing the tank contents, and
pumping to longer-term storage.
The tanks should be equipped with nitrogen blanketing as it is sometimes
required under individual State Implementation Plans to minimize evaporative
losses. Two 100 gallons/ minute gear pumps are required per blending tank -
one for transferring materials into the tank and one for pumping them out.
Gear pumps were specified because they afford a reasonably tight shut-off and
prevent leaking when not in operation. A 100 gallons/minute capacity would
be needed to achieve rapid transfer of materials (e.g., empty the tank in ap-
proximately 200 minutes). Two hundred feet of three-inch piping was assumed
to be neede^ for connecting tne blend tank to other storage and handling fa-
cilities.
The total installed cost of a system with only one 20,000 gallon blend-
ing tank was estimated at $74,000 including pumps and piping. This system
would provide up to 20,000 gallons of blended material per day or 100,000
gallons per week for the typical five day per week blending operation. It
would produce 595 gallons per hour of waste fuel for continuous furnace fir-
ing. It was considered the minimum practical size for blending waste for
furnace firing. Larger blending capacities may be obtained by using multi-
ple units. Costs associated with blending larger quantities may estimated
by multiplying the price of one unit by the number of units required.
Straining of Solids
Liquid wastes with high solids content may cause several problems includ-
ing increased apparent viscosity, burner gun nozzle blockage, obstruction of
piping, and possibly increased particle emissions. Because of these potential
problems, the solids content should be sufficiently restricted to provide* a
liquid that is pumpable and free of grit ani debris. In-line strainers have
5-9
-------
been used to protect pumps and burner guns in the even: that large particles
turn up in the waste. Blending may be used to reduce me solids level but
other pretreatment techniques such as filtering are not generally practiced
because of the expense and the need to dispose of the removed solids which
would be classified as hazardous waste.
Typically, two different sets of duplex strainers are needed. A 1/8-
inch opening screen basket is requir
-------
FIGURE 5.1
EQUIPMENT DIAGRAM FOR THERMAL TREATMENT OF HAZARDOUS WASTES
RECYCLE
TO STORAGE
STORAGE
TANKS ARE
INSULATED
AND HEATED
FROM
STORAGE
O
O
BACK-PRESSURE
REGULATOR
STEAM
FUEL
HEATER
TO
KILN
DUPLEX
STRAINER
CONDENSATE
m
in
m
m
•s
O
8
m
8
m
-------
and piping. The installed costs of this equipment are plotted as a function
of waste feed rate in Figure 5.2 as Curve 1.
Wastes of greater than 10,000 standard saybolt units viscosity at ambi-
ent temperature must not only be treated to insure good atomization, out must
also be kept hot enough to prevent them from setting up in the storage tank
and piping. All waste received at the waste derived fuel storage facility
must be pumpable. The equipment required to handle waste in this category
include the heat exchanger for heating the waste as it is pumped to the fur-
nace, provisions to recirculate the waste back to the storage tank, as well
as itarns to keep the liquid warm:
o Storage tank insulation
o Storage tank heaters
o Pipe tracing and insulation
o Addition of a spare circulating pump
Installed costs of this equipment, excluding the storage tank insulation and
heaters, are plotted as a function of waste throughput in Figure 5.2 as curve
2. Although waste storage tank costs are not part of the authorized scope of
this study, the tank heater and insulation costs are provided. These costs
are presented in Table 5.5. The storage tank heater for which costs are pre-
sented is the immersion steam coil type. Insulation costs are for three
inches of fiberglass insulation.
Furnace Modification Costa
Burner Modification Costs
The cost for modifying an existing burner system to fire hazardous waste
is site specific. It depends on the existing burner type and capacity, type
of conventional fuel fired, properties of the waste, and quantity of waste to
be fired. The least expensive approach is likely to be taken. Some furnaces
require only that a burner gun be replumbed to fire the waste. This would
not require significant capital expenditure. In other instances, the hazard-
ous waste could be blended with the conventional fuel and fired with no mod-
ifications to the burner. This approach could be used when the wasts and
conventional fuel are compatible or when burning liquid waste in the fuel
oil-fired burners.
Costs given below are for providing the necessary burner components to
fire a liquid hazardous waste in natural gas, oil and combination fossil fuel-
fired furnaces. It was assumed that the waste was piped to the burner, i.e.,
costs do not include a fuel handling train. The figures were obtained from
burner vendors and, therefore, may be different from actual costs because
some furnace operators may fabricate their own waste burners.
One approach to firing waste materials is to install a dedicated waste
burner gun in or adjacent to the conventional fuel burner. Waste is simply
atomized into the primary fuel (natural gas or oil) flame envelope. This
arrangement may be used for co-firing waste up to 30% of the total heat in-
put. A good quality atomizing burner gun, properly sized for the range of
waste flows can be purchased for $10,000 to $15,000, depending on the length
of the burner. The tc'.al installed cost in 1982 dollars, including plumbing
and flame safeguard system, is from $20,000 to $30,000.
5-12
-------
E=S ENGINEERING-SCIENCE -
FIGURE 5.2
INSTALLED CAPITAL COSTS FOR THERMAL
TREATMENT OF HAZARDOUS WASTES
100
ui _-
eg SO
O
G
£ 20
*t
H 10
O
U
_J
E
u
o
IU
I-
tf!
Z
2 —
10
CURVE
CURVE 2
2C
50 100 200
WASTE FLOW, CPH
500
1000
CURVE-1- PUMPABLE AT AMBIENT TEMPERATURES BUT MUST BE HEATED
FOR GOOD ATOMIZAT1ON.
CURVE-2- MUST BE HEATED TO KEEP PUMPABLE AND TO OBTAIN GOOD
ATOMIZATION.
5-13
-------
TABLE 5.5
STORAGE TANK HEATER AND INSULATION INSTALLED COSTS
Tank Size Heater Costs Insulation Costs
(gallons) (1982 dollars) (1982 dollars)
500 11,000 430
1,000 12,000 66C
2,000 14,000 960
5,000 17,000 1,310
10,000 19,000 2,850
20,000 38,000 3,640
5-14
-------
It is assumed that the process controls for modulating an additional
burner are not necessary. The furnace could be annually based loaded on the
waste fuel with the existing process controls being used to modulate the con-
ventional fuel and combustion air flows. Based on the detailed study of the
furnaces and their current practices, this assumption is valid and should
extend to other furnace types.
Carbon Monoxide and Oxygen Monitoring
Continuous monitoring of carbon monoxide levels in the exhaust gases of
a furnace burning a hazardous waste is deemed necessary to ensure that good
combustion conditions are maintained to provide adequate destruction of the
POHCs and PICs. Oxygen monitorin.., is required in conjunction with CO moni-
toring to adjust CO levels to a common excess air rate indicated by excess
oxygen content in the flue gas. Correcting CO levels to a common flue gas
oxygen content avoids the problem of having (otherwise) high CO levels di-
luted by large quantities of excess air. Some furnaces are already equipped
with oxygen and/or carbon monoxide monitoring to save fuel costs through in-
creased combustion efficiency, and/or for safety purposes. Most of the CO
monitors installed on cement kilns are for detecting explosive or unburned
hydrocarbon concentrations and are nog designed to measure the low CO levels
typical of optimum combustion conditions (0-5000 ppm). These devices typical
operate in a concentration range of 0-10%.
The cost of CO and oxygen continuous emissions monitoring systems for a
"clean" environment is considerably less than that for a "dirty" application.
There is not a clear distinction between a "clean" and a "dirty" exhaust gas.
For purposes of this analysis, however, a "dirty" exhaust gas application is
defined as one that requires an extractive monitoring system in which the
extracted sample must be treated to reduce the gas temperature, particulate
loading, and moisture content. A sample location in the backend of a dry
cement kiln is an example of a "dirty" application. A "clean* application
example is a sample location downstream of the air pollution control deveice.
Typical costs for oxygen and carbon monoxide continuous emission moni-
toring systems for clean applications are $15,000 and $20,000 respectively
(1982 dollars). These costs include analyzers, sample transport system (if
extractive type unit), chart recorder and installation. If an automatic data
reduction system is desired an additional cost of $20,000 would be incurred
(Reference 5).
For a more hostile environment, the cost of the continuous emission mon-
itor systems (CB*S) will be significantly higher due to the added cost of
specialized sample conditioning equipment. Providing an unadulterated sample
that is compatible with the analyzers is more difficult in sample locations
where there are extremely high temperature, moisture, and particulate loading.
The cost of special equipment needed to adjust these stack gas characteristics
increases with the number of characteristics that must be adjusted and the de-
gree of adjustment required. For purposes of this analyses it will be assumed
that the conditioning system must treat a flue gas that requires a water-coded
probe and has a high moisture content and particulate loading.
5-15
-------
Waste Feed Metering
If limitations on the hazardous waste feed rate are established based on
the trial burn results* capital outlays for flow metering will be necessary.
Two types of liquid flow measurement devices well-suited for this application
are the positive displacement meter and the orifice meter. These units are
relatively inexpensive ana are applicable to a wide range of wastes. Either
device can be obtained for approximately $2,000 to meter flows up to 7,000
gallons per hour, which is the maximum flow rate one would anticipate for
waste f-ad to the industrial furnaces being considered. Some type of record-
ing device is needed to provide a permanent record of the waste faed rate.
A simple $2,000 chart recorder would serve this purpose adequately. Instal-
lation is lively to cost an additional $1,000. Thus, the total installed
cost of a liquid waste feed metering system will be approximately $5,000 in
1982 dollars.
Air Pollution Control Cost
The iss.ua of particulate matter, metals, and hydrochloric acid emissions
from a furnace burning hazardous waste need to be considered on a source spe-
cific basis. The furnaces considered in detail in this study are already
equipped with air pollution control systems for removing particulate matter
from the. furnace exhaust gases. II is possible that most of these systems
will be able to meet adopted toxic metal emission'standards should they be
adopted. It is assumed that metals will be controlled by either particulate
matter controls or waste fuel specifications. Furthermore, hydrochloric acid
emissions may not be a problem if operators do not burn chlorinated waste at
chloride levels that cculd cause the adopted emission levels to be exceeded.
However, should a furnace operator chose to burn HWOF's that would cause ac-
ceptable health risks from toxic metals and hydrochloric acid emission to be
exceeded, additional air pollution controls would be required.
The type of control system that would be installed will vary depending
on the emission limitations eventually adopted and the exhaust gas parameters.
For study purposes, costs are presented for a combination venturi scrubber
for particulate matter removal followed by a packed bed absorber for HC1 re-
moval. The venturi scrubber will remove metals that are contained in the
exhaust gases as particulate matter while those in the vapor state will be
removed by the packed tower. Costs are presented as a function of furnace
exhaust gas flow. Factors are also given to estimate costs if only metals
as particulate matter or HC1 removal is required. Other combinations of tox-
ic metals and HC1 removal are available, but the venturi/absorber is a prac-
tical technique that adequately represents the costs element needed to as-
sess the economic impact of pollution control equipment that may be required.
This approach is somewhat conservative in that the packed tower may not be
necessary in all cases to accomplish similar results.
Installed cost for a combination venturi/absorber system may be esti-
mated from the following equation:
Cost » 96 x Q0.8164
where: Q - the exhaust gas flow rate in acfm
5-16
-------
This system includes a quench tower to lower the exhaust temperai_are from
550°F to saturation, a venturi scrubber for particle collection, acid gas
absorber, caustic recycle system for neutralizing the scrubber water, ID
fan, stack, and auxiliaries. The assumed materials of construction are:
o High-nickel-alloy quencher and venturi throat
o High-grade, chemically resistant, high-temperature fiberglass shell
for the cyclonic separator and packed tower
o Polypropylene tower packing
o Inconel or HasteXloy fan wheel with rubber-lined steel housing
If no venturi scrubber is needed for metals control, the total system
cost is reduced by 15%.
If acid gas absorption is not required, the total system cost is re-
duced by approximately 40%.
Costs represented by the above equation are also based on purchased
equipment cost contained in Reference 6 with installation assumed to be 100%
of the purchased cost. These costs are typical for a venturi pressure drop
requirement of 30-inches water column, which should be adequate for this ap-
plication. They are indexed to 1982, the year covered by the OSW Burner
Questionnaire which is being used in the RIA.
OPERATING AND MAINTENANCE COSTS
The operating and maintenance costs for a furnace operation are like-
ly to be greater when 100% waste fuel or a combination of waste and conven-
tional fuels are burned than when 100% conventional fuels are burned. Addi-
tional storage and handling facilities are typically required to fire wastes
and these must be maintained. If agitators or nitrogen blanketing are used,
operating costs will increase. When the wastes require pretreatment before
burning, additional O&M costs are incurred. There may also be increased
furnace O&M costs an a result of adding a waste burner gun. However, these
costs are not expected to be significant.
The equipment needed to meet the regulatory requirements that are even-
tually adopted will likely further increase the O&M costs associated with
firing hazardous waste over those associated with firing conventional fuels.
Air pollution control devices added to meet emission limitations will in-
crease the O&M cost burden. Further costs will be incurred to maintain oxy-
gen and/or carbon monoxide monitoring and waste metering. O&M costs asso-
ciated with waste metering are, however, expected to be insignificant.
This section presents O&M costs for the following of the aforementioned
items:
o Waste Characterization and Pretreatment
o Furnace Modification Costs
o Air Pollution Control Devices
Increased O&M costs, associated with waste storage and handling other than
pretreatment, are provided by others.
5-17
-------
Waste Characterization Pretreatment O&M Costs
The annualized O&M costs associated with waste characterization and the
three pretreatn.3nt processes (bxending, straining, and thermal treatment) for
which capital costs were given earlier in this section are presented here.
Waste Characterization Cost
As previoesly discussed, furnace operators can avoid high O&M costs to
upgrade hazardous waste by limiting the materials that they will accept to
those that require only blending, straining, or thermal treatment tc make
them suitable for fuel. This practice requires that each shipment of waste
be analyzed to determine if it meets established specifications. Wastes
should be analyzed for heating value, halogens, sulfur, water, ash, speci-
fic gravity, toxic metals, and PCBs. These analyses may be made by a plant
chemist or by an independent commercial laboratory. The need for rapid re-
sults requires the analyses to be made at a laboratory near the plant. Since
metal and PCB determinations require more sophisticated analytical procedures
and equipment, it is assumed that these are performed at a nearby commercial
laboratory while the other analyses are completed in the plant laboratory.
O&M costs for the waste characterization approach described above will,
therefore, include simple charges for the analyses performed by the outside
firm and the labor and other costs associated with the plant's waste analyses.
Assuming 30 samples are analyzed per week for PCB by gas chromatography and
up to five metals by atomic absorption, the annual charges by the outside
laboratory is estimated at $156,000 in 1982 dollars.
Labor for waste characterizations by the plant's chemist and his super-
visor is estimated at $26,500. Maintenance and indirect O&M costs are taken
at 22.2% of the capital costs of the laboratory space and equipment. These
costs are $16,600 which brings the total annual waste characterization O&M
costs to $199,100 in 1982 dollars.
Pretreatment
Certain elements of the pretreatment costs are generic to all three pro-
cesses. These are listed in Table 5.6. As shown in Table 5.6, the O&M costs
include both direct and indirect components. The direct components include
operating labor, maintenance, and utilities. Operating labor is taken at
$9.75/manhour. Estimated labor requirement is two manhours for waste blend-
ing. For straining and thermal treatment, it is ansumed that no operating
labor is needed. Supervision is estimated at 15% of the total operating la-
bor costs (Reference 7). Maintenance requirements are difficult to predict
accurately for these types of operations. For such situations, maintenance
is generally taken at 2-6% of the capital costs (Reference 8). Five percent
was used in these estimates.
Utilities required for the pretreatment processes include electricity
to drive pumps and the blend tank agitator, nitrogen for blanketing the blend
tanks, and steam for the thermal pretreatment. Pump power consumption is es-
timate., from the following equation:
5-18
-------
TABLE 5.6
COMPONENTS OF ANNUALIZED OSM COSTS
Direct
Operating Costs
Cost Factor*
Operating Labor
- Operator
- Supervisor
Maintenance
Utilities
- Electricity
- Steam
$9.75/manhour
15% of operator
5% of capital costs
SO.05/kilot* tt-hour
$6.00/1,000 pounds
Indirect
Operating Costs
Cost Factor*
Overhead
Property Tax
Insurance
Adainis tration
Capital Recovery
Costs
80% of operating
labor and main-
tenance labor
1% of capital costs
1% of capital costs
2% of capital costs
0.132 (using i •
10% and an equipment
life of IS years)
All costs are in 1982 dollars.
5-19
-------
kilowatt-hours - 0.746 (gpm) (hd) (sg) H
3960 n
where: gpm - flow rate, United States, gallons/ninute
hd - head of fluid, feet
sg • specific gravity relative to water 9 60°F, 29.92 incnes mercury
n » overall pump/motor efficiency - 40*
H • hours of operation
Agitator horsepower for the 20,000 gallon tank is assumed to be 3 horsepower.
An electricity cost of $0.05 per kilowatt-hour (Reference 9) was used in the
power costs determination. Unit cost and quantity of nitrogen needed for
blending the blend tank are used on data taken from Reference 6.
Steam is needed for tne thermal pretreatment. An average cost of $6.00/
1,000 pounds of steam at 100 pounds/square inch was used. The indirect oper-
ating costs include the costs of overhead, taxes, insurance, administration
expense*, and capital charges. Taxes, insurance, and administration can col-
lectively be estimated at 4% of the capital costs, wnile overhead charges
can be considered at 80% of the labor charges for both OtM. The annualized
capital charges reflect the costs associated with capital recovery over the
depreciable life of the system and can be determined as follows:
Capital Recovery Cost - (capital costs) x * * * *
(1 * i)n - 1
where: i • annual interest rate
n - capital recovery period
for these estimates, a useful life of 15 years and an average annual interest
rate of 10% were assumed.
Blending O&M Costs
The estimated annual 0«M costs for the previously described tank blend-
ing system is $36,000. These costs are based on a five day per week blend-
ing operation using a <0,000 gallon blend tank equipped with agitation and
nitrogen blanketing. Wastes are either transferred from other part* of the
plant or unloaded from a tank truck or rail car into the tank where they are
upgraded to the desired quality by adding othe- wastes or fuel oil. The
waste mixture i* continuously agitated to achieve uniform blending. Af-
ter the desired quality is obtained, the blended waste is pumped to either
another tank for long-term storage or directly to the burner. Cost* are
based on the assumption that it take* eight hour* to prepare 20,000 gallons
of blended waste which is also the maximum daily production rate of the sys-
tem. One operator is required two hours per day to oversee the blending
process. Utilities include electricity to drive the agitator and transfer
pumps and nitrogen for blanketing the tank. The nitrogen can be either
vented to the furnace or to the same system a* used for the storage tanks.
The blending O4M costs trill vary with the amount of fuel blended. Costs
presented here are for one 20,000 gallon tank system which will provide 595
gallon* per hour of blended waste* OCM cost* for furnace* firing more than
the capacity of the 595 gal/hr blending system can be obtained by multiplying
5-20
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the costs presented here for this system by the number of multiple blending
systems required. This can be determined by dividing the production capacity
to be fueled with waste by 595 gal/hr and rounding to the nearest whole num-
ber. For example, a 3,000 tens/day blast furnace firing 7 gallons of waste
fuel per ton pig iron produce would consume 875 gal/hr of the waste. Two
20,000 gallon blending systems (595 gal/hr) are required to produce the nec-
essary waste fuel.
875 gal/hr , 1.47 (2 rounded to nearest
595 gal/hr whole number)
Therefore, the O&M costs to blend the waste fuel for this furnace is two
times the costs presented for the 20,000 gallon system, i.e., $72,000.
Straining O&M Costs
The O&M costs associated with removing grit and debris with basket
strainers are considered insignificant for purposes of the RIA.
Thermal Treatment O&M Costs
Figure 5.3 presents the annualized thermal treatment O&M costs as a
function of waste feed rate for the two categories of waste for which capi-
tal coats were given earlier in this section:
o Curve 1 - Wastes with viscosities greater than 750 standard sayboIt
units but less than 10,000 standard saybolt units at ambient tempera-
tures.
o Curve 2 - Wastes with viscosities greater than 10,000 standard say-
bolt units at ambient temperatures.
Provisions for heating and insulating of the storage tanks are not included
in the O&M costs presented in Figure 5.3. Wastes with viscosities greater
than 10,000 standard saybolt units require tank heating and insulation while
wastes with viscosities between 750 and 10,000 standard saybolt units at
ambient temperatures do not. The following are O&M costs for storage tank
heating and insulating:
O&M Costa - Thermal Treatment
Tank Size (gallons) O&M Costs (1982 dollars/year)
500 470
1,000 890
2,000 1,710
5,000 2,190
10,000 3,900
20,000 5,380
5-21
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ENGINEERING - SCIENCE -
FIGURE 5.3
ANNUALJZED O&M COSTS FOR THERMAL TREATMENT
OF HAZARDOUS WASTES
100
10 20 50 100 200
WASTE FLOW, CPH
500
1000
CURVE-1- PUMPABLE AT AMBIENT TEMPERATURES BUT MUST BE HEATED
FOR GOOD ATOM1ZATION.
CURVE-2- MUST BE HEATED TO KEEP PUMPABLE AND TO OBTAIN GOOD
ATOMI2AT1ON.
5-22
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Furnace Modification O&M Costs
Burner Modification O&M Costs
The burner gun to fire waste fuel should require little operator atten-
tion beyond that required for the furnace firing conventional fuels. Main-
tenance cost will be about 5% of capital cost, capital recovery 13.2%, and
taxes, insurance, and administration, 4%. Total annual Ot~'i cost will be
about 22.2% of the original burner gun assembly capital cost.
Oxygen and Carbon Monoxide Monitoring O&M Costs
Annual operating costs for several continuous monitoring systems have
been estimated for evaluating the economic impact of NSPS for industrial boil-
ers (Reference 7). These costs should also be applicable to "clean" exhaust
gas applications. An annual O&M cost of $18,500 in 1982 dollars was estimated
for an oxygen monitoring system. Costs for a carbon monoxide system should be
about the same. The major items included in this estimate are the maintenance
and performance certification. One-half manhour per day was assumed to be re-
quired for the maintenance at a rate of $35.81/manhour, including supervisor
and overhead. One certification test per year, costing $11.900 was assumed.
The operating and maintenance cost of a CEMS for dirty gas is expected
to be higher than for a clean gas application. The extent to which these
cost will be higher will depend on the type of conditioning system selected
cod to some degree will be site-specific. The labor will be approximately
30% higher for a system for a dirty gas application based on an assumed one-
half manhour per day labor requirement. Thus, for a dirty gas system, three
quarter-manhours per day would be required for 0/M. At the assumed ?35.81/
manhour labor rate (1982 dollars) used above the 0/M cost would be $21,000
(1982 dollars) which includes $11,900 for one certification test.
Requiring 02 and CO monitors on industrial furnaces burning hazardous
waste could result in a fuel cost savings to the operators of these devices.
This potential saving would result if the operators used the 02 monitors to
maintain low excess air (LEA) combustion of the fuels. With LEA combustion,
less fuel is required because less heat is lost out the stack with the com-
bustion gases.
The magnitude of the potential fuel savings that can be obtained by LEA
combustion must be determined individually for each furnace because it depends
on many factors. The major factors influencing the potential savings include:
o Furnace type and condition
o Burner type and condition
o Combustion control type and condition
o Operating load level
The furnace type and condition have a large impact on the amount of fuel
saving that may be achieved through LEA combustion. Some types have design
characteristics that limit the range of LEA operation. Also, the flue gas
exit temperature for one type furnace can be significantly different from
those of another type. Since the fuel savings for a given excess air reduc-
tion is temperature dependent furnaces with higher exit flue gas temperatures
5-23
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should be capable of achieving a higher fuel savings per unit excess air re-
duction. The condition of the furnace also impacts the fuel savings poten-
tial of LEA. A furnace that has significant air in-leakage is .-nore difficult
to operate at low excess air levels because the air infiltration may distort
the O2 reading drastically.
The type and condition of the burner(s) installed in the furnace also
greatly influence the fuel savings potential of LEA operation. A burner is
designed to operate efficiently over a specific excess air range. If oper-
ated at an excess air range lower than the design level, proper mixing of the
fuel and combustion air cannot be achieved. Poor air and fuel mixing would
likely result in incomplete combustion of the fuel and higher fuel consump-
tion. Gas burners generally can operate at lower excess air levels than oil
burners which generally operate at lower levels than coal burners. There is
also a wide variation in tne excess air level operations capability of burn-
ers for a given fuel. For example, design excess air levels for oil burners
used in asphalt dryers can vary from five tc twenty percent. The condition
of the burner also affects the potential fuel savings because the fuel flow
through a dirty or damaged burner is difficult to control.
Another important factor determining the potential of LEA combustion
and hence fuel savings is the type and condition of the combustion controls.
Combustion controls vary widely in complexity from the simple single-point
positioning units typically found on smaller units to the metering system of
a complex, computerized process control system. Interfacing the 02 monitor
to these systems has limitations that are unique to each type of control sys-
tem. The level cf LEA achievable is limited to how well the Q^ monitoring
is used by the control system. Also, the condition of control system mech-
anical components also impacts the fuel savings potential. Damper linkage
may flax slightly, and bearings may wear over time. Even metering systems
are susceptible to some shortcomings, since their flow transmitters are op-
erated at temperatures and pressures that vary significantly from those at
which the transmitters were initially calibrated.
More excess 02 is needed at low loads because of poorer mixing of the
fuel and air. Consequently, the operating load level also impacts the fuel
savings of LEA combustion.
Because of the influence of the factors discussed above, a detailed
breakdown of potential fuel savings by furnace type and fuel is deemed un-
justified. For the purpose of determining the economic impact of requiring
02/CO monitoring, two estimates of this potential fuel saving is considered
adequate. A 2% savings is estimated as a typical average value for all the
furnaces discussed in Section 3 except asphalt and lightweight aggregate
kilns. A 4% savings is estimated for asphalt and lightweight aggregate fur-
naces because these units are typically operated at very high excess air
levels. Both estimates are based on discussions with combustion control
equipment suppliers, information found in the literature, and limited data
on oxygen levels and furnace exit flue gas temperatures. These estimates
are also based on the assumption that a 0.5% increase in combustion effi-
ciency is achieved per 1% reduction in the 02 level in the flue gas.
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Not all furnace operators would receive the fuel saving estimated for
LEA operation as a consequence of requiring 02/CO monitoring. Many of the
larger industrial boilers are already equipped with O2-trim or C>2/CO-trinu
In fact, those industrial furnaces equipped with CO-trim systems will actual-
ly be required to operate at a higher LEA level than they are currently op-
erating at and thus wiuld consume more fuel. Furnaces with CO-trim systems
typically operated with a CO setpoint of from 200 to 400 ppm. A 100 ppm CO
limit would require that they operate at a higher LEA level than their cur-
rent setpoint level. Also, nearly all sulfur recovery furnaces are equipped
with O2-trim systems. Thus, estimating the fuel savings potential of requir-
ing O2/CO monitors on a particular population of furnaces requires a know-
ledge of how many units in the population already are operating at LEA levels
(i.e., how may are using 02 or CO monitors to achieve LEA combustion.) Once
the fraction of furnaces currently employing LEA controls is determined, the
potential fuel savings for the entire population may be estimated from the
potential savings of a single unit.
The savings of a single furnace can be estimated by multiplying the to-
tal annual fuel cost by 0.02 or 0.04 depending on the type fuel burning de-
vice being considered. The annual fuel cost is estimated by multiplying the
design heat impact by the unit fuel cost presented in the proceeding para-
graphs. For example, the maximum potential annual fuel savings of a 150 x
106 Btu/hr, residual oil-fired furnace would be:
.02 x 150 x
106 Btu/hr x 8760 hrs/yr x S4.62/106 Btu - $121,400
This assumes that the furnace operates 24 hours per day, 365 days a year.
This savings can be adjusted to match different assumptions regarding load
factor.
A comprehensive survey of furnaces was not conducted to determine the
fraction of units already equipped with an LEA capacity. Conversations with
industry representatives and control system vendors indicate the approximate
breakdown listed below:
Furnaces % With Some Form of LEA Cap
Lightweight Aggregate 30
Blast Furnaces
Stoves 50
Boilers 50
Spent Acid Recovery 50
Asphalt 0
Reverberatory 50
Air Pollution Control Devices O&M Costs
The annualized O&M ccsts for the venturi/gas absorption systems pre-
sented in Figure 5.4 are based on 8,700 hours/year operating time and the
cost factors presented in Table 5.7. The O&M costs include direct costs
such as operating labor and materials, maintenance, replacement parts,
utilities, and collected particulate disposal. Also included are indi-
rect costs such as overhead, insurance, taxes, and capital recovery.
5-25
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Estimated operating labor requirement for the air pollution control de-
vice system is four manhours per shift. The utilities include quench water,
scrubber water, absorber water, caustic soda, and electricity.
5-26
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FIGURE 5.4
ANNUALIZED OPERATION AND MAINTENANCE COSTS
FOR THE VENTURI/GAS ABSORPTION SYSTEMS
1C.OQC
ui
a;
= 1,000
100,
10,000
100,000
EXHAUST GAS RATE, a fern
1,000 000
5-27
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TABLE 5.7
COMPONENTS OF ANNUALIZED O&M COSTS FOR
AIR POLLUTION CONTROL DEVICES
Direct
Operating Costs
Cost Factor*
Operating Labor
- Operator
- Supervisor
Maintenance
Utilities
- Electricity
- Steam
$9.75/manhour
15% of operator
5% of capital costs
$0.5/kiIowatt-hours
$6.00/1,000 pounds
Indirect
Operating Costs
Cost Factor*
Overhead
Property Tax
Insurance
Administration
Capital Recovery
Costs
80% of operating
labor and main-
tenance labor
1% of capital costs
1% of capital costs
2% of capital costs
0.132 (-using i *
10% and an equipment
life of 15 years)
* All costs are in 1982 dollars.
5-28
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REFERENCES
1. Energy Information Administration. Monthly Energy Review. Washington,
D.C., Publication DOE/EIA-0035 (83/1213]). December 1983.
2. Energy Information Administration. Coal Production - 1982. Washington,
D.C., Publication DOE/EIA-0118 (82). Septonber 1983.
3. Memorandum from T- Hogan, Energy and Environmental Analysis, Inc., to R.
Short. EPA:EA3. June 22, 1983.
4. Engineering Handbook for Hazardous Waste Incineration - Cincinnati, Ohio.
U.S. Environmental Protection Agency, EPA SW-889. 1981.
5. Dickerman, J.C. and Kelly, M.E. Issue Paper: Compliance Monitoring
Costs. Radian Corporation, Durham, North Carolina. September 25, 1980.
6. McCormick, R.J. and DeRosier, R.J. (Acurex Corporation). Capi'^al and
O&M Cost Relationships for Hazardous Waste Incineration. Prepared for
the U.S. Environmental Protection Agency. EPA Contract 68-02-3176 and
68-03-3043. July 1983.
7. Chilton, C.H. Cost Engineering in the Process Industries. McGraw-Hill,
New York, 1980.
8. Peteru, M.S., and Timmerhause, K.D. Plant Design and Economics for
Chemical Engineers. McGraw-Hill, New York, 1980.
9. Comparative Evaluation of Incinerators and landfills for Hazardous Waste
Management. Prepared by Engineering-Science for the Chemical Manufactur-
ers Association. May 1982.
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