-------
This review has found two strong acid units which have started
operation since 1971.5 Under existing State regulations,6'7 the NOX
emissions from these strong acid plants are below the level of the NSPS.
Therefore, the rationale for excluding strong acid plants is still
appropriate, and this document will not further discuss strong acid plants.
2.3 EMISSIONS FROM NITRIC ACID PLANTS
The main source of atmospheric emissions from the manufacture of
nitric acid is the tail gas from the absorber tower. The emissions are
primarily nitric oxide and nitrogen dioxide with trace amounts of nitric
acid mist. Each of these pollutants has an effect on the color and
opacity of the tail gas plume. The presence of nitrogen dioxide is
indicated by a reddish-brown color. Since nitric oxide is colorless, the
intensity of the color and, therefore, plume opacity is directly proportional
to the nitrogen dioxide concentration in the plume. A convenient rule of
thumb is that a stack plume will have a visible brown color when the NOo
concentration exceeds 5,100 ppm divided by the stack diameter in centimeters.2
This means that the threshold of visibility for a 5-cm diameter stack is
about 1200 ppm of N02 and for a 30-cm stack, 200 ppm of ;J02-
The opacity of the plume is also a function of the amount of nitric
acid mist in the tail gas, which is dependant on the type of process
used, the extent of mist entrapment, and the efficiency of entrainment
separators. For those acid processes operated above atmospheric pressure,
the tail gases are reheated and expanded for power recovery purposes and
discharged to the atmosphere at 200° to 250°C (392° to 482°F). At this
temperature, any acid mist present is converted to the vapor state. In
atmospheric pressure processes, however, the temperature of the tail gas
is below the dew point of nitric acid. As a result, the acid is emitted
as a fine mist which increases the plume opacity. The average emission
factor for uncontrolled acid plants is 20 to 28 kg N0x/Mg (40 to 56 Ib
N0x/ton) of acid, with typical uncontrolled tail gas concentrations on
the order of 3000 ppm NOX. This concentration would be experienced in a
low pressure plant. The NOX concentration in the tail gas of medium
pressure plants ranges from 1000 to 2000 ppm.
2-10
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Nitrogen oxide emissions vary considerably with changes in plant
operation. Several operating variables have a more significant effect on
increasing NOX emissions. These include: (1) insufficient air supply to
the oxidizer and absorber; (2) low pressure, especially in the absorber;
(3) high temperatures in the cooler-condenser and absorber; (4) production
of an excessively high-strength product acid; and (5) operation at high
throughput rates. Finally, faulty equipment, such as compressors or pumps,
lead to lower pressures and leaks which decrease plant efficiency and
increase emissions.
2.4 INDUSTRY CHARACTERIZATION
2.4.1 Geographic Distribution
In 1972 there were approximately 125 nitric acid units in existence,
exclusive of government-owned units at ordnance plants. About 75 percent
of these units were 10 years old or older and, in general, had capacities
of 27C fig/day (300 tons/day) or less. The remaining 25 percent of the
units were of more recent and larger design, having capacities exceeding
270 Mg/day (300 tons/day). The Bureau of the Census reported that there
were 72 plants (involving one or more units) in 1972 producing nitric
acid in the U.S. and that by 1977 the net number of plants in production
had increased by only one.
The largest consumer of nitric acid is the fertilizer industry which
consumes 70 percent of all nitric acid produced; industrial explosives
use 15 percent of acid produced. Other end uses of nitric acid are gold
and silver separation, military munitions, steel and brass pickling,
photoengraving, production of nitrates, and the acidulation of phosphate
rock.
As of March 1983, 29 nitric acid units subject to NSPS had come on-
stream. The heaviest concentration of new or modified nitric acid unit
construction since 1971 appears along the coast of the Gulf of Mexico and
within the Mississippi River delta. The distribution of nitric acid plants
displays a spacial pattern similar to that of the major fertilizer
production centers. Since the bulk of all nitric acid produced is consumed
2-11
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captively in the manufacture of nitrogen fertilizer used mainly in the
Midwest cornbelt, the South Central States, and the Southwest, the
similarity in spacial patterns between nitric acid plants and fertilizer
manufacturing plants is to be expected.
2.4.2 Production
In 1971, U.S. production of 100 percent nitric acid totalled 6,928,000
megagrams (7,638,000 tons)8 and increased to 8,200,000 megagrams (9,040,000
tons) in 1981.9
The average rate of production increase for nitric acid fell from
9 percent/year in the 1960-1970 period to 1.7 percent from 1971 to 1981.
The decline in demand for nitric acid parallels that for nitrogen-based
fertilizers during the same period.
In 1971, the EPA predicted the start-up of five new nitric acid
units per year for several years after promulgation of the NSPS. The
actual average rate of start-up between 1971 and 1982 has been between
two and three units per year.
2.4.3 Trends
About 50 percent of plant capacity in 1972 consisted of small to
moderately sized units (50 to 300 ton/day capacity). Because of the
economics of scale, some producers are electing to replace their existing
units with new, larger units. Also, the trend toward reduction of NOX
emissions is stimulating the shutdown and replacement of older units.
'Jew nitric acid production units have been built as large as 910 Mg/day
(1000 tons/day). The average size of new units is approximately 430 Mg/day
(500 tons/day).
2.5 SELECTION OF NITRIC ACID PLANTS FOR NSPS CONTROL
Nitric acid plants were originally selected for NSPS development
because they can be large point sources of nitrogen oxides (NOX). Without
emission control, a modern plant producing 454 megagrams (500 tons) per
day of nitric acid would release about 454 kilograms (1,000 pounds) of
NOX per hour at a concentration of 3,000 ppm by volume. The growth rate
was projected to be five new units per year. As stated above, the actual
growth rate has been about three units per year.
2-12
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2.6 REFERENCES
1. A Review of Standards of Performance for New Stationary Sources - Nitric
Acid Plants, U.S. Environmental Protection Agency, EPA-450/3-79-013.
March 1979.
2. Control Techniques for Nitrogen Oxides Emissions from Stationary
Sources - Revised Second Edition, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina, EPA-450/3-83-002, January 1983.
3. Concentrating Nitric Acid By Surpassing An Azeotrope, L. M. Marzo and
J. M. Marzo, Chemical Engineering, November 3, 198U, pp. 54-55.
4. Control of Air Pollution From Nitric Acid Plants (Draft Report).
U.S. Environmental Protection Agency, Durham, North Carolina, June 1970.
5. World-Wide HPI Construction Box Score, Hydrocarbon Processing, 1971-
1982:
6. Telephone conversation between B. Sigmore, West Virginia Air Pollution
Control Commission, and J. Eddinger, U.S. EPA, on July 1, 1983.
7. Environmental Reporter, Bureau of National Affairs, Inc., Washington,
D.C., July 20, 1979, p. 521:0681.
8. Predicasts Basebook, Predicasts, Inc., Cleveland, Ohio, 1982.
9. Chemical Engineering & News, May 3, 1982.
2-13
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3.0 CURRENT STANDARDS FOR NITRIC ACID PLANTS
3.1 FACILITIES AFFECTED
The NSPS regulates nitric acid plants that were planned or under
construction or modification as of August 17, 1971. Each nitric acid
production unit (or "train") is the affected facility. The standards of
performance apply to new facilities producing so-called "weak nitric
acid" (defined as 50 to 70 percent strength). The standards do not apply
to the various processes used to produce strong acid by extraction or
evaporation of weak acid, or by the direct strong acid process.
An existing nitric acid plant is subject to the NSPS if: (1) it is
modified by a physical or operational change in an existing facility
thereby causing an increase in the emission rate to the atmosphere of any
pollutant to which the standard applies, or (2) if in the course of
reconstruction of the facility, the fixed capital cost of the new components
exceeds 50 percent of the cost that would be required to construct a
comparable entirely new facility that meets the NSPS.
3.2 CONTROLLED POLLUTANTS-AND EMISSION LEVELS
Total nitrogen oxide emissions from nitric acid plants are controlled
under the NSPS, as defined by 40 CFR 60, Subpart G (as originally
promulgated in 36 FR 24881 with subsequent modifications in 39 FR 20794):
(a) On and after the date on which the performance test required to
be conducted . . .is completed, no owner or operator subject
to the provisions of this subpart shall cause to be discharged
in to the atmosphere from any affected facility any gases which:
(1) Contain nitrogen oxides, expressed as N02, in -excess of
1.5 kg per metric ton of acid produced; (3.0 Ib per ton),
the production being expressed as 100 percent nitric acid.
(2) Exhibit 10 percent opacity, or greater.
3-1
-------
3.3 TESTING AND MONITORING REQUIREMENTS
3.3.1 Testing Requirements
Performance tests to verify compliance with the NOX standard must be
conducted within 60 days after the plant has reached its full capacity
production rate, but not later than 180 days after the initial start-up
of the facility (40 CFR 60.8). The EPA reference methods (40 CFR 60,
Appendix A) to be used in conjunction with NOX compliance testing include:
1. Method 7 for the concentration of NOX
2. Method 1 for sample and velocity transverses
3. 'Method 2 for velocity and volumetric flow rate
4. Method 3 for gas analysis
Each performance test consists of three runs, each consisting of at
least four grab samples taken at approximately 15-minute intervals. The
arithmetic mean of the runs constitutes the value used to determine whether
the plant is in compliance.
Method 7A (Ion Chromatograph) has been proposed as an alternative
.nethod for Method 7 for determining compliance with the NSPS. Method 7A
offers improvements over Method 7 in that the sample analytical time is
shortened and precision is improved. This method utilizes the evacuated
flask sampling procedure outlined in Method 7, and the recovered sample
is then analyzed by ion chromatograph.
Acid produced, expressed in tons per hour of 100 percent nitric acid
is required to be determined during each testing period by suitable
methods and shall be confirmed by a material balance over the production
system. The method generally used to determine acid production by the
plants reviewed during this study is flowmeters. Other methods used are
acid inventory, calculations based on air flow or ammonia flow, and
weighting the acid produced over a certain interval.
3.3.2 Monitoring Requirements
The NOX levels in the tail gas from new nitric acid plants are required
to be continuously monitored to provide: (1) a record of performance and
(2) information to plant operating personnel such that suitable corrections
can be made when the system is out of adjustment. Plant operators are
3-2
-------
required to maintain the monitoring equipment in calibration and to
furnish records of excess NO* emission values to the Administrator of the
EPA or to the responsible State agency as requested.
The continuous monitoring system is calibrated using a known air NOg
gas mixture as a calibration standard. Performance evaluation of the
monitoring system is conducted using the EPA Method 7. In general, the
system in use should satisfy the specifications as shown in 40 CFR 60,
Appendix B, Performance Specification 2.
The operator is required to establish a conversion factor for the
purpose of converting the monitoring data into units of the standard.
The conversion factor is to be established by measuring emissions with
the continuous monitoring system concurrent with measuring emissions with
the reference method tests.
The production rate and hours of operation are also required to be
recorded daily.
Excess NOX emissions are required to be reported to the EPA (or
appropriate State regulatory agencies) for all 3-hour periods of excess
emissions (or the arithmetic average of three consecutive 1-hour periods).
Periods of excess emission are considered to occur when the integrated
(or arithmetic average) plant stack NOX emission exceeds the 1.5 kg/Mg
(3 Ib/ton) standard.
3-3
-------
4. STATUS OF CONTROL TECHNOLOGV
The nethods of emission control being employed on nitric acid
units subject to the NSPS are presented in this chapter. As discussed
in Chapter 2, the NOX content of the tail gas in any nitric acid plant
is a function of the extent to which the absorption reaction reaches
completion. Nitric acid plants can be designed for low NOX emission
levels without any add-on processes. Such plants are usually designed
for high absorber efficiency; high inlet gas pressures and effective
absorber cooling. However, some new plants are not designed for MOX
emission levels low enough to meet the NSPS. For these plants, add-on
abatement methods are necessary. Therefore, to achieve the NSPS, nitric
acid plants must extend the absorption reaction, add a control device
to the exhaust stream, or both.
The control methods used by units subject to the NSPS include
extended absorption, catalytic reduction, and chilled absorption with
caustic scrubbing. Catalytic reduction was used as the basis for the
MSPS. Since that time fuel costs have risen, and all but one of the
units which have started operation since the 1979 review are designed
for high absorber efficiency (extended absorption).
4.1 EXTENDED ABSORPTION
The most obvious method of reducing NOX emissions in the tail gas
of a nitric acid plant is to increase the absorption efficiency.
Emission control by absorption is somewhat misleading, since no add-on
emission control equipment is necessary if the plant is designed and
built with sufficient absorption capacity. Nitric acid plants have
been constructed with absorption systems designed for 99.7 plus percent
NOX recovery.
In the extended absorption process, the increased absorption
capacity is achieved by installing a single larger absorber or adding a
second absorption tower in series to the existing absorber. The NOX is
4-1
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absorbed by water and forms nitric acid. The economics of the extended
absorption process generally require the inlet gas pressure at the
absorber to be at least 730 kPa (107 psig).1 There is normally no
liquid effluent from extended absorption; the weak acid from the
secondary absorber is recycled to the first absorber, increasing the
yield of nitric acid. Figure 4-1 is a schematic flow diagram of a
nitric acid plant using extended absorption by means of a second
absorber. Figure 4-2 is a schematic flow diagram of a unit using only
a single larger absorber for emission control.
A smaller volume and number of trays in the absorption system are
required when the use of mechanical refrigeration for chilling part of
the cooling water is employed. Two cooling water systems are used for
cooling the absorbers. The first part of the absorption process is
cooled by the normal cooling water available at the plant site.
Approximately one-third of the trays are cooled by normal cooling
water. The balance of the trays in the absorption system are cooled by
cooling water at about 7°C (45°F), which is achieved by mechanical
refrigeration. The refrigeration process is normally a part of the
ammonia vaporization section of the nitric acid plant.
The extended absorption system operates without any problems as
long as design conditions are met. This means that the absorber pressure
and oxygen content in the gas to the absorber must not be below design
level, and the temperature and NOX content in the gas stream must not
exceed design level. With regard to temperatures, this system is
vulnerable to high summer ambient temperatures in the southern tier of
States, i.e., temperatures in excess of 35°C (95°F). Information from
several extended absorption nitric acid plants confirms this potential
problem. The plants indicated, however, that they have compensated for
these periods of excessive ambient temperatures by designing the unit
to allow them to decrease cooling water temperature or by increasing
the bleach and secondary air flow.2>3,4
Of the 10 nitric acid plants that have started operation since the
1979 review, 8 feature extended absorption as the NOX control mechanism.
It appears that the increases in natural gas prices have made extended
4-2
-------
Tail Gas
-pi
OJ
Ammon i a
N-
Air
/
^
TfC
I
Compressor
^
•>
>
f
/"~^\
V
>
^
i
Converter
k
•J
^
\
^
f
Heat
\ /
/ \
^~
f
Absorber
\
/ ^
Condenser
1
1
1
I
1— A UCTIIvJCvJ
Absorber
f ""1
L
>. '
V
Recovery ~
f
N
j
1 '
1 '
1
1
1 1
' 1
1 ^*
I
/
c Process
Water
1 IT
r Weak Acid
• —
1
Power
Recovery
i
Product
Acid >
Figure 4-1. EXTENDED ABSORPTION SYSTEM USING SECOND
ABSORBER FOR K!0 CONTROL
-------
Ammonia
A
Air
Compressor
Y
£-
Reactor
\L
\L
Heat
Recovery
Chilled.
Water
Cool ing
Water
>
Condenser
Tail Gas
A
^Process
Water
Power
Recovery
t\
roduct
Acid
Figure 4-2. EXTENDED ADSORPTION SYSTEM USING ONE
LARGE ABSORBER FOR NO CONTROL
A
-------
absorption the preferred process for NOX abatement in the future. In
fact, one plant using catalytic reduction indicated that if they were
to install a new acid plant, they would probably use the extended
absorption because of the lower operating costs.5
4.2 CATALVTIC REDUCTION
Catalytic reduction was widely used as an NOX abatement system
on new nitric acid plants built between 1971 and 1977. Due to rapid
fuel price escalations since 1975, new installations have chosen extended
absorption. Catalytic reduction was also used as a method of NOX
decolorization on over 50 percent of the nitric acid plants built prior
to the NSPS. The reasons for the prevalence of this control technology
until 1975 were:
(1) Its relative ease and flexibility of operation.
(2) The recovery of waste heat.
(3) High NOX removal efficiencies.
(4) Relatively cheap cost of fuel.
In practice, the catalytic reduction unit is an integral part of
the plant (Figure 4-3). The tail gas from the absorption tower is
preheated by heat exchange with the converter effluent gas. Fuel is
added and burned in the catalytic unit to generate heat and reduce the
NOX concentration in the tail gas. The hot gas from this unit passes
to an expander which drives the process air compressor for the ammonia
converter. A waste heat boiler removes the heat from the expander
outlet gas in the form of steam, and the treated tail gas is vented to
the atmosphere. In some cases, a waste heat boiler is required after
the catalytic unit to keep the expander inlet temperature below its
design maximum—usually 677°C (1,250°F).
Catalytic reduction processes can be divided into two categories:
nonselective and selective reduction. In nonselective reduction, the
tail gas from the absorber is heated to the necessary ignition temperature
and mixed with a fuel such as methane, carbon monoxide, or hydrogen.
When methane (natural gas) is used as the fuel, the following reactions
take place:
CH4 + 202 -* C02 + 2H20 (1)
CH4 + 4N02 ^ 4NO + C02 + 2^0 (2)
CH4 + 4NO -> 2\\2 + C02 + 21^0 (3)
4-5
-------
Cooler
Nitric Condensers
Acid
Condenser
3-
M
-<
f_f ^,
Waste Heat Steam
Generator
n
Platinum Filter I
n
1
Catalytic and Tall Gas
Treatment . Healer
Unit
FIGURE 4-3.
ACID PLANT INCORPORATING CATALYTIC REDUCTION
FOR NOX ABATEMENT1
-------
The first two reactions proceed -ri-'dly with the evolution of heat
which is recovered in a waste 'vr Diler. In the second reaction, or
decolorization step, the nitro^ "14s is converted to nitric oxide,
so the gas is colorless even fio :; there has been no decrease in the
total nitrogen oxides. Only the last reaction with additional methane
results in the reduction of the nitric oxide to nitrogen. The final
reduction step must be limited to an upper temperature of 843°C (1,550°F),
due to the catalyst thermal limitation. If reduction has to be carried
out in the presence of high oxygen concentrations (above 3.0 percent),
it must be performed in two stages to prevent exceeding the upper
temperature limit. In practice, 98 percent control efficiency of the
NOX in the tail gas has been achieved by this process.5
In the selective reduction process, ammonia is used to catalytically
reduce N02 to N2 without simultaneously reacting with oxygen. A ceramic-
supported platinum catalyst is used to effect the following reactions:
3NH3 + 6N02 •»• 7^2 + 12^0
4NH3 + 6NO -». 5M2 + 6^0
Both of these reactions occur at relatively low temperatures (210° to
270°C).
The advantage of this method is that less heat is evolved and the
installation of heat removal equipment is unnecessary. However, the
catalyst required is more expensive and the ammonia cost may not be
competitive with other fuels even when less is required. Close
temperature control is required to prevent ammonia oxidation, which
would increase nitrogen oxide emissions. Startup and shutdown procedures
must also be closely controlled to avoid formation of ammonium nitrate
salts.
Of the 10 nitric acid plants subject to the NSPS which have started
operation since the 1979 review, only 1 features catalytic reduction as
the MOX control method. This plant uses natural gas as the fuel.
4-7
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4.3 CAUSTIC SCRUBBING
Caustic scrubbing involves treatment of the absorber tail gas with
solutions of sodium hydroxide to absorb MO and NO? in the form of
nitrate and/or nitrite salts in a scrubbing tower. In caustic scrubbing,
the following reactions take place:
2MaOH + 3N02 + 2NaN03 + NO + H20
2MaOH + NO + N02 ^ 2NaM02 + H20
However, disposal of the spent scrubbing solution presents a serious
water pollution problem. One nitric acid plant subject to the NSPS
employs a combination of chilled extended absorption and caustic
scrubbing to achieve NOX abatement. At this unit, the caustic scrubber
(Figure 4-4) is located in the top of the absorber. The caustic solution
is recycled in the scrubber with a portion bled to the absorber. This
caustic bleed-off results in an acid loss.5
4.4 REFERENCES
1. A Review of Standards of Performance for New Stationary Sources--
Nitric Acid Plants, U.S. Environmental Protection Agency,
EPA-45Q/3-79-013, March 1979.
2. Letter and enclosure from F. W. Berryman, Chevron Chemical Company,
to Jack R. Farmer, U.S. EPA, dated March 16, 1983.
3. Letter and enclosure from Joseph M. Roman, Terra Chemicals
International, Inc., to Jack R. Farmer, U.S. EPA, dated March 1, 1983.
4. Letter and enclosure from Ben T. Traywick, Apache Powder Company,
to Jack R. Farmer, U.S. EPA, dated February 24, 1983.
5. Trip Report - Columbia Nitrogen Corporation, Augusta, Georgia,
February 16, 1983.
6. Trip Report - Agrico Chemical Company, Catoosa, Oklahoma,
February 7, 1983.
4-8
-------
k Emission to Atmosphere
Intercooler
Steam
Turbine
Air
Compressor
Tail Gas
Expander
Filter
Ammonia
Air
Reactor
Haste
Heat
Boiler
Heat
Recovery
Cooler
Condenser
Caustic
Scrubber
Process
c Lonaensate
Nitric Acid
Absorber
Tower
Nitric Acid
Figure 4-4. SCHEMATIC OF NITRIC ACID PLANT INCORPORATING
CAUSTIC SCRUBBING FOR NO CONTROL6
A
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5. COMPLIANCE TEST RESULTS
EPA regional offices, State agencies, and nitric acid plants were
contacted to obtain compliance test information for facilities which are
subject to the NSPS and have started operation since the 1979 review.
The results of the survey show that there are 10 new nitric acid
units which have started operation since the 1979 review. Data obtained
include the average NOX emissions and the 100 percent nitric acid production
rates at the time of the tests. Also obtained were quarterly emission
monitoring reports for 1981 and 1982.
5.1 ANALYSIS OF fJSPS COMPLIANCE TEST RESULTS
The results of compliance tests obtained from new nitric acid plants
are summarized in Table 5-1. Compliance test results from the 10 nitric
acid units indicate that all but one unit are in compliance with the
NSPS. The units are controlled by either catalytic reduction, extended
absorption, or chilled absorption and caustic scrubbing.
The nitric acid unit which is not yet in compliance with the NSPS is
utilizing extended absorption and has never completed the start-up phase.
This unit is owned by the U.S. Army and is installed for ammunition
production. The unit has never been operated except for a two-day start-up
period during which time the unit was compliance tested and shut down.
Discussions with plant personnel indicate that there are no plans to
restart the unit.1 It is installed as a standby unit for ammunition
production during wartime. The plant personnel also indicated that
modifications would be made to bring the unit into compliance prior to
any startup. However, due to budget limitations, these modifications
cannot be scheduled until 1987.
5-1
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Table 5-1. COMPLIANCE TEST RESULTS FOR NITRIC ACID PLANTS
SUBJECT TO THE NSPS SINCE THE 1979 REVIEW2-H
Average
Control MOX Emissions
Plant Technique (Ib/ton)
A Chilled Absorption & 1.84
Caustic Scrubbing
B Catalytic Reduction 1.13
C Extended Absorption 1.3
D Extended Absorption 2.75
E Extended Absorption 1.8
*F Extended Absorption 4.1
G " Extended Absorption 2.55
H Extended Absorption 2.31
I Extended Absorption 2.74
J Extended Absorption 2.13
NSPS = 3.0
* Plant tested upon start-up, was then shutdown, and has not restarted,
5-2
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5.2 ANALYSIS OF NOX MONITORING RESULTS
Quarterly emission monitoring reports for 1981 and 1982 were obtained
on seven nitric acid plants subject to the NSPS which have come on-line
since the 1979 review. Table 5-2 summarizes these quarterly reports.
Five of the seven units have maintained emissions below the tiSPS
95 percent of the time or greater during the two-year period. The excess
emissions generally occurred during startups and shutdowns due to forced
plant outages. Other causes of excess emissions were problems with the
chilling system, high cooling water temperature, and leaks in the tail
gas heater. Leaks in the heater allow N0x-rich gas to leak into the
exhaust gas downstream of the pollution control equipment. Leaks in the
expander gas heater were the principal cause of the excess emissions for
the other two units (Plants E and H). Plant E maintained emissions below
the HSPS only 90 and 80 percent of the time in 1981 and 1982, respectively.
The reheater leak at Plant E occurred in the last quarter of 1981 and was
not corrected until the second quarter of 1982. This unit maintained
emissions below the NSPS over 97 percent of the time in the first three
quarters of 1981, and returned to a high reliability of maintaining
emissions below the MSPS in the last two quarters of 1982.
Plant H has experienced problems in continuously operating with
emissions below the NSPS since startup of the unit in 1979. The initial
compliance test conducted in August 1980 indicated an emission rate of
3.17 pounds per ton. This unit generally maintained emissions below the
NSPS until a leak developed in the expander gas heater in late 1980.
Monitoring data prior to the leak indicated to the company that they
could not maintain 60 percent acid strength (design level) and maintain
emissions below the NSPS. Therefore, the acid strength was reduced. The
leak in the expander gas heater was repaired at the end of the first
quarter of 1981. The unit was then again operating with emissions below
the IJSPS. A second compliance test conducted in April 1981 indicated an
MOX emission rate of 2.81 pounds per ton. The unit operated with
emissions below the NSPS, for the most part, in the second quarter of
1981. With the arrival of hot weather in June, the company was unable to
keep the emissions below the NSPS on a continuous basis. In August 1981,
5-3
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Table 5-2. SUMMARY OF NOV MONITORING DATA FOR NITRIC ACID PLANT SUBJECT TO THE N!SPS2~8
A
)urs Hours in Excess
Principal Cause of
Excess Emissions
Percent of
Plant
A
C
D
E
G
H
I
Time in
1981
99.8
98.0
99.6
90.2
96.3
43.4
95.9
Compliance
1982
99.7
98.9
97.2
79.8
95.8
1.0
96.1
Total Hours
In Excess
of NSPS
39
230
97
2,380
328
6,281
389
Hours in Excess
due to Startup
or Shutdown
24
159
63
44
164
681
117
Forced plant outages
Forced plant outages
Leak in Reheater
1) High cooling water temperature
2) Leak in tail gas heater
Leak in expander gas heater
Chiller problems
-------
several modifications were made to the unit in an-effort to increase the
absorption tower efficiency and, thus, decrease NOX emissions. These
modifications included reducing the acid concentration to 54 percent,
adding potassium carbonate to the chilled water system to lower the water
temperature without freezing up the system, increasing the pressure on
the absorption system by closing back on the hot gas expander inlet
valve, and by operating the compressor set at the fastest speed possible
at all times to maintain the highest air pressure possible. These modifi-
cations resulted in the unit achieving the fJSPS during the winter months
(low ambient temperatures) until leaks developed again in the expander
gas heater. The leaks are felt to be caused by the thermal stressing in
the unit due to the extreme temperature differences between unit operation
and unit shutdown. The plant made several attempts to repair the leaks;
and it was determined that the main expander support springs on the
expander gas heater failed, and that this lack of support for the unit
had created stresses and possible misalignment in the tube sheet resulting
in the tube sheet cracking. These leaks caused excess emissions from the
fourth quarter of 1981 until the plant was shutdown in the second quarter
of 1982. In mid-August 1982, the unit was brought back on-line. The
corrective action taken in the expander gas heater reportedly eliminated
the problems encountered with the leaks. However, additional process
design modifications failed to bring the MOX emissions down to the level
of the fJSPS. Due to the current economic situation, the unit was shutdown
indefinitely in September 1982.
Discussion with a vendor representative confirmed that the high MOX
emissions at Plant H were caused by leaks, but that a further problem
exists because the design pressure [850 kPa (125 psig)] is not being
achieved.12 The vendor stated that the design of this unit is similar to
other units in operation, and it is designed for operation during the
summer high ambient temperatures. The vendor was prepared to perform
tests during the hot months to determine the results of the latest modifi-
cations, but these were cancelled when the unit was shutdown and not
5-5
-------
restarted due to economic conditions. The vendor indicated that there
are no plans for further modifications until the unit is started up and
results of the latest modifications have been analyzed.
Monitoring reports for 1981 and 1932 were obtained on one nitric
acid plant subject to the rJSPS which is controlled by catalytic reduction.
The data showed that the unit maintained emissions below the fJSPS over
99.7 percent of the time in both 1981 and 1982.
5.3 STATUS OF UOX EMISSION MONITORS
The NSPS requires installation of an instrument for continuously
monitoring and recording NOX emissions. The continuous monitor in wide use
is based on the principle of photometric analysis. The monitors installed
on nitric acid plants subject to the NSPS have been very reliable according
to those plants that have started operation since the 1979 review. Three
plants have reported greater than 98 percent reliability.4,5,8 Routine
maintenance on the monitor is reported to be about one manhour per week.3,8
The main problem has been deterioration of the ultraviolet lamp resulting
in frequent replacement. These monitors have been installed for emissions
monitoring only.
The continuous monitoring system is calibrated using a known air-N02
gas mixture as a calibration standard. Performance certification of the
monitoring system is conducted using the EPA Method 7. In general, the
system in use should satisfy the specifications as shown in 40 CFR 60,
Appendix 3, Performance Specification 2.
5.4 REFERENCES
1. Telephone Conversation between Don Hartman, Badger Army Ammunition
Plant, and James Eddinger, U.S. EPA, on January 17, 1983.
2. Letter and enclosure from J. Brad Willett, American Cyanamid Company,
to Jack R. Farmer, U.S. EPA, dated April 29, 1983.
3. Letter and enclosure from F. W. Berrymen, Chevron Chemical Company,
to Jack R. Farmer, U.S. EPA, dated March 16, 1983.
4. Trip Report - Agrico Chemical Company, Catoosa, Oklahoma, February 7,
1983.
5. Letter and enclosure from Ben T. Traywick, Apache Powder Company, to
Jack R. Farmer, U.S. EPA, dated February 24, 1983.
5-6
-------
5;Q Tn''-° Report - Gulf Oil Chemicals Company, Jayhawk, Kansas, February 8,
Letter and enclosure from Kenneth E. Jury, N-ReH Corporation to
,aj:> R. Farmer, U.S. EPA, dated March 4, 1983.
3. Letter and enclosure from Joseph M. Homan, Terra Chemical International
Inc., to Jack R. Farmer, U.S. EPA, dated March 1, 1983.
9. Letter and enclosure from Jack S. Divita, U.S. EPA-Region VI, to
Stanley T. Cuffe, U.S. EPA, dated November 24, 1982.
10. Memo from J. Brian Galley, Wisconsin Department of Natural Resources
to Jim Eddinger, U.S. EPA, dated November 8, 1982.
11. Trip Report - U.S. EPA-Region VII Office, Kansas City, Missouri,
February 9, 1983.
12. Telephone Conversation between Glenn Smith, D.M. Weatherly Company and
James Eddinger, U.S. EPA, on March 3, 1983.
5-7
-------
6. COST ANALYSIS
This chapter presents the updated costs of control systems required to
achieve the current fJSPS covering nitric acid plant tail-gas emissions. Two
control systems are analyzed: (1) the extended absorption process and
(2) the catalytic reduction process. Capital and annualized costs of
each control option are estimated for three model plant sizes: 131, 454
and 907 megagrams (200, 500, and 1000 tons) of nitric acid production
(100 percent basis) per day. The cost data are presented in January 1983
dollars, and the developed costs are compared with actual costs reported
by the industry.
The control system includes all the equipment and auxiliaries required
to provide the specified emission control. The capital cost of a control
system includes all the cost items necessary to design, purchase, install,
and commission the control system. In addition to the direct costs, the '
capital cost includes such indirect items as engineering, contractor's fee,
construction expense, and a contingency.
The annualized cost represents the cost of owning and operating the
control system. The operating cost covers the utilities, supplies, and
labor required to operate and maintain the system on a day-to-day basis.
The cost of owning the system includes capital-related charges such as
capital recovery, property taxes, insurance, and administrative charges.
6.1 EXTENDED ABSORPTION PROCESS
6.1.1 Capital Costs
The costs of an extended absorption process are estimated for the
three model plant sizes. The costs represent the incremental costs of
achieving the New Source Performance Standard compared with an uncontrolled
plant. The control system consists of a secondary absorber and condensation
system for recovery of absorbed nitric acid. The most important of
several design alternatives to be considered are the tail-gas pressure
and temperature and the temperature of the gas leaving the secondary
absorber. Some plants use only well water in the absorption tower,
6-1
-------
whereas others use refrigerated or chille^ water. The tail-gas pressure
determines the shell thickness of the an _-/•, and the temperatures
generally affect the gas flow rate and I-- ;^e absorber size. Figure 6-1
shows the basic conditions for the theorer •->] system used in this study.
All gas and liquid volumes and the absorber volume are proportional to
plant capacity. Regardless of its size, the absorber, a bubble-tray
column, has 39 trays. Figure 6-2 presents a schematic of the entire
extended absorption system. The condensation system includes a chiller,
compressor, condenser, chilled water tank, and necessary pumps and piping.
Estimates of the capital costs of the absorption system are based on
published cost data."1.2 jhe purchase cost of each system component was
estimated, and installation, labor, and material were added to obtain the
total installed cost. This cost includes all the necessary ancillaries,
such as foundations, insulation, and ladders. The indirect costs were
factored from the direct costs. All of these costs and factors were taken
from References 1 and 2 and updated to January 1983 dollars per the
Chemical Engineering (CE) Plant Cost Index. Tables 6-1 through 6-3 show
capital costs of an extended absorption system for the three model plants.
These cost estimates define the curve shown in Figure 6-3. This figure
also shows the capital costs reported by four plants (updated to January
1983 dollars) in their responses to EPA information requests. This
figure indicates a close correlation between estimated and reported costs.
6.1.2 Annualized Costs
The annualized costs include the direct operating costs for the
pumps, water chiller, and absorber. Utilities and direct operating labor
costs are based on the following estimates:
Plant size, Mg/day
Cost element
Water, m3/s
Electricity, GJ/yr
Labor, h/yr
Pumps, GJ/yr
Chiller, GJ/yr
18!
0.0032
4300
2150
1200
3100
454
0.0090
10900
3225
3100
7800
90 /
0.016
23400
4300
7900
15500
6-2
-------
TAIL GAS OUT
ABSORBENT IN
C.D032m3/s (SOgpm
TAIL GAS IN
22.7 m3/s (48,200scfro
689 kPa (lOCpsigJ
4.44-C (40"F)
CHILLED WATER IN
-0.115 m^sg-l.e?0: (1820gpmat29cF)
V « 2*9 m3 (8800 ftJ)
OIA * 3.66 m (12 ft)
HGT =24.4 m (80 ftj
SHELL
THICKNESS-1.905 on (3/4 in
CHILLED WATER OUT
15 m3/s P-I.I
WEAK ACID, EQUIVALENT TO
7.26 Mg/day(8 TPD)g lOOi CONCENTRATION
ALL COMPONENTS OF TYPE 304 STAINLESS STEEL
Figure 6-1. Secondary absorber tower input and
for a 454 Mo/day (500 TPD) nitric^ ac?o
6-3
-------
Oi
I
ABSORBENT GAS TO ATMOS.
FEED PUMP (2)
SECONDARY
ABSORBER
GAS IN
RETURN
PUMP (2)
WEAK ACID
PUMP (2)
Note: All systems have two
pumps and drives for
redundancy.
MAKEUP WATER (2)
13-
CHILLER
CHILLED WATER COMPRESSOR (1)
PUMP (2)
CHILLED WATER
SURGE TANK
CHILLED WATER
FEED PUMP (2)
CONDENSER
Figure 6-2. Schematic of extended absorption system.
-------
TABLE 6-1. CAPITAL COST SUMMARY FOR AN
EXTENDED ABSORPTION SYSTEM [PLANT
WITH A CAPACITY OF 181 Mg/day (200 tons/day)]
(in January 1983 dollars)
Description
A. Direct Costs
1. Absorber tower3
2. Pumps and drives^
3. Chilled water system0
4. Piping, valves, and fittings^
5, Electrical
6. Instrumentation^
Total Direct Costs (TDC)
3. Indirect Costs
K Contractor's fee (6% of TDC)9
2. Engineering (10% of TDC)9
3. Construction expense (8% of TDC)9
Total Indirect Costs (TIC)
C. Contingency (10% of TDC and TIC)9
Total Capital Cost
? Reference 1, pp. 768, 769, 770, 772.
» Reference 1, pp. 555, 557, 558.
c Reference 2, pp. 265, 278.
a Reference 1, pp. 529, 530.
£ Reference 1, p. 171.
f Reference 1, p. 170.
9 Reference 1, p. 164.
Cost,
$1000
330
77
20
75
44
44
590
35
59
47
141
73
804
6-5
-------
TABLE 6-2. CAPITAL COST SUMMARY FOR AiJ
EXTENDED ABSORPTION SYSTEM [PLANT
WITH A CAPACITY OF 454 Mg/day (500 tons/day)]
(in January 1983 dollars)
Description
Cost,
$ 1300
A. Direct Costs
1. Absorber towera
2. Pumps and drives'3
3. Chilled water system0
4. Piping, valves, and fittings01
5. Electrical
6. Instrumentation^
Total Direct Costs (TDC)
3. Indirect Costs
1. Contractor's fee (5% of TDC)9
2. Engineering (10* of TDC)9
3. Construction expense (8% of TDC)9
Total Indirect Costs (TIC)
C. Contingency (10% of TDC and TIC)9
Total Capital Cost
558
100
40
185
74
74
1031
52
103
82
247
128
1406
a Reference 1, pp. 768, 769, 770, 772.
b Reference 1, pp. 555, 557, 558.
c Reference 2, pp. 265, 278.
d Reference 1, pp. 529, 530.
e Reference 1, p. 171.
f Reference 1, p. 170.
9 Reference 1, p. 164.
6-6
-------
TABLE 6-3. CAPITAL COST SUMMARY FOR AN
EXTENDED ABSORPTION SYSTEM [PLANT
WITH A CAPACITY OF 907 Mg/day (1000 tons/day)]
(In January 1983 dollars)
Description
Cost,
$1000
A. Direct Costs
1. Absorber tower3
2. Pumps and drives^
3. Chilled water system0
4. Piping, valves, and fittingsd
5. Electrical^
6. Instrumentation^
Total Direct Costs (TDC)
B. Indirect Costs
1. Contractor's fee (6% of TDC)9
2. Engineering (10% of TDC)9
3. Construction expense (8% of TDC}9
Total Indirect Costs (TIC)
C. Contingency (10% of TDC and TIC)9
Total Capital Cost
a Reference 1, pp. 768, 769, 770, 772.
b Reference 1, pp. 555, 557, 558.
<• Reference 2, pp. 265, 278.
d Reference 1, pp. 529, 530.
J Reference 1, p. 171.
f Reference 1, p. 170.
9 Reference 1, p. 164.
818
191
70
292
109
109
1589
95
159
127
381
197
2167
6-7
-------
3000
2800
2600
2400
2200
~ 2000
< 1800
o 1600
S 1400
. 1200
o
o
o
1000
900
800
700
600
500
400
COSTS REPORTED IN RESPONSES
A TO EPA REQUESTS FOR INFORMATION:
UPDATED TO JAN. 1983 DOLLARS.
100
200
300 400 500
900
PLANT SIZE Mg/day
Figure 6-3. Capital cost of extended absorption system
for nitric acid plant.
6-8
-------
acid recovered varies greatly from plant to plant, and its value is
somewhat uncertain. Although nitric acid prices are quoted in the Chemical
Marketing Reporter, these prices are not directly applicable because most
of the manufacturing plants are captive facilities and hence there is no
established market. As shown in Table 6-4, the reported prices do not
fluctuate as one would expect of a commodity chemical. The table also
shows that the concentration greatly affects the value; the higher grade
is currently worth approximately 40 percent more than the lower grade (on
a 100 percent nitric acid basis). Thus, although some manufacturers have
reported acid credits, there is no correlation between these credits and
plant size. For comparison purposes, consider the effect of control
efficiencies and acid prices on a 454 Mg/day plant as follows:
Assumed
base efficiency, Increased efficiency, Acid recovered, Credit, S1000
/£>
98
98
98
98
98
7o
0
1.0
1.2
1.4
1.6
Mg/yr
0
1836
2204
2571
2880
$215/Mg
0
358
430
501
561
S308/Mg
n
514
617
720
806
Since the estimated annualized costs for an extended absorption system on
such a plant is about $610,000 (without acid credit), the net annualized
cost can range from as much as +$250,000 to -$200,000.
The value of the recovered acid is based on the following
assumptions:
(1) Acid production increases by 1.6 percent.
(2) The increased production is a weak acid having a value of
S195 per ton.
Tables 6-5 through 6-7 present a breakdown of the annualized cost
estimates for each model plant. These estimates define the cost curves
shown on Figure 6-4. The annualized cost data reported in the responses
to EPA requests for information were not complete enough to be compared
6-9
-------
TABLE 6-4. NITRIC ACID PRICES*
(S/Mg)
Year
1975
1976
1977
1978
1979
1980
1981
1982
Acid Concentration
52.3 - 67.2%
127
127
127
• 127
193
193
193
215
94.5 - 98%
231
231
231
231-264
264
264
264
308
a Year-end prices based on data reported by Chemical Marketing
Reporter: all prices on 100% nitric acid basis.
6-10
-------
A.
TABLE 6-5. ANNUALIZED COST SUMMARY FOR AN
EXTENDED ABSORPTION SYSTEM [PLANT WITH
A CAPACITY OF 181 fig/day (200 tons/day)]
(In January 1983 dollars)
Cost element
~ •
DIRECT OPERATING COSTS
1. Utilities
a. Water ($0.50/1000 gal)
b. Electricity ($0.05/kWh)
2. Operating Labor
a. Direct ($15/man-hour)
b. Supervision (20? of direct labor)
3. Maintenance and Supplies (42 x Capital Cost)
a. Labor and material
b. Supplies
CAPITAL CHARGES
1. Overhead
a.
b.
Plant (50% x A2 and A3 above)
Payroll (20% x A2 above)
2. Fixed Costs
a. Capital recovery (13.5% x Capital Cost)
b. Insurance, taxes, and G&A (4% x Capital Cost)
C. SUBTOTAL
D. CREDIT FOR RECOVERED ACID
E. NET ANNUALIZED COST
Cost,
SI 000
13
60
32
6
32
36
3
106
32
325
224
101
6-11
-------
TABLE 6-6. AfJNUALIZED COST SUMMARY FOR AN
EXTENDED ABSORPTION SYSTEM [PLANT WITH
A CAPACITY OF 454 fig/day (500 tons/day)]
(in January 1983 dollars)
Cost element
Cost,
$ 1000
CRECT OPERATING COSTS
1. Utilities
a. Water (SO.50/1000 gal)
b. Electricity ($0.05/kWh)
2. Operating Labor
a. Direct ($15/man-hour)
b. Supervision (20% of direct labor)
3. Maintenance and Supplies (4% x Capital Cost)
a. Labor and material
b. Supplies
36
151
48
10
56
3. CAPITAL CHARGES
1. Overhead
a. Plant (50% x A2 and A3 above)
b. Payroll (20% x A2 above)
2. Fixed Costs
a. Capital recovery (13.5% x Capital Cost)
b. Insurance, taxes, and G&A (4% x Capital Cost)
59
12
185
56
SUBTOTAL
D. CREDIT FOR RECOVERED ACID
E. MET AtiliUALIZED COST
613
561
52
6-12
-------
TABLE 6-7. ANN UAL IZED COST SUMMARY FOR AM
EXTENDED ABSORPTION SYSTEM [PLANT WITH
A CAPACITY OF 907 Mg/day (1000 tons/day)]
(in January 1983 dollars)
Cost element
Cost,
Si 000
A. DIRECT OPERATING COSTS
1. Utilities
a. Water ($0.50/1000 gal) 65
b. Electricity ($0.05/kWh) 325
2. Operating Labor
a. Direct ($15/man-hour) 65
b. Supervision (20% of direct labor) 13
3. Maintenance and Supplies (4% x Capital Cost)
a. Labor and material
b. Supplies 87
CAPITAL CHARGES
1. Overhead
a. Plant (50% x A2 and A3 above)
b. Payroll (20% x A2 above)
2. Fixed Costs
a. Capital recovery (13.5% x Capital Cost)
b. Insurance, taxes, and G&A (4% x Capital Cost)
35
16
285
87
C. SUBTOTAL
CREDIT FOR RECOVERED ACID
NET ANN UAL IZED COST
1028
1118
(90)
6-13
-------
1000
800
600
500
400
5 300
—I
o
Q
CO
txs
200
§ 150
100
80
60
50
40
300
400 500
900
PLANT CAPACITY, Mg/day
Figure 6-4. Annual ized costs of extended absorption system
for nitric acid plant.
6-14
-------
with the estimated costs. Also, as previously stated, the costs are
highly sensitive to the quantity and quality of the recovered acid. The
problem of comparing annualized costs is exacerbated further by the
scarcity of open-market price data.
6.2 CATALYTIC REDUCTION
6.2.1 Capital Costs
Although nonselective reduction of tail-gas pollutants is generally
considered a part of the process (because of the recovery of the heat),
it is generally recognized that some portion of the system constitutes
air pollution control. For this study, we assume that the catalytic
treatment unit, the catalyst, the short run of pipe on either side of the
unit for the gases, and the fuel lines are all allocable to pollution
control. Mo public sources of cost information could be found for the
catalytic reduction unit. This unit is unlike normal incinerators
because of the high pressure (689 kPa) of the inlet gases. Both
D. M. Ueatherly and a fabricator of such units were contacted; however,
because of the proprietary nature of the unit and the lack of specific
design specifications, they were unable to provide any cost data.
Reportedly, one plant has a unit for which it paid a turnkey price of
52.3 million (actual reported figure updated to January 1983 dollars).
This represents the cost of the catalytic unit and the catalyst. The
application of this cost to the model plants, by use of the Six-Tenths
Power Rule, yields the following capital costs:
Plant capacity, Mg/day Capital cost, $lp6 (Jan. 1983 dollars)
200 0.94
500 K63
1000 2.47
6.2.2 Annual ized Costs
Direct annualized costs consist of the fuel (natural gas assumed)
used in the catalytic reduction unit, operating labor, and maintenance
labor and supplies. Effective fuel use is reduced by post-oxidation heat
recovery. According to one manufacturer's response to an EPA request for
6-15
-------
information, a unit that treats 30.1 m3/s (64,000 scfm) of tail gas consumes
about 1237 m3 (45,000 ft3) of natural gas per hour. The heat content of
this natural gas is about 45.6 GJ (43 million Btu), of which 23.5 GJ
(22.2 million Stu), or 52 percent, is recovered downstream. Thus, the
net energy requirement is about 0.00574 GJ (0.00542 million Btu) per
28.3 m3 (1000 scf) of tail gas. Direct operating labor is estimated at
0.5 man-hour per shift, regardless of the unit size. As with the extended
absorption system, maintenance and supplies are estimated at 4.0 percent
of the capital cost of the facility. This includes the average cost of
catalyst replacement. Reportedly, the catalyst must be replaced every 3
to 8 years at a cost of about 5350,000 for a plant producing 816 Mg/day
(900 tons/day). Thus, the estimated average annual cost of catalyst
replacement at the model plants is:
Plant size, Mg/day Cost, $1000
181 14
454 36
907 71
Because the catalytic reduction process is less complex than the
extended absorption process, one would also expect maintenance costs to
be less, but the catalyst replacement costs tend to equalize the overall
expense.
Estimates of indirect costs (capital charges) are based on percentage
factors similar to those used for the extended absorption system costs.
Tables 6-8 through 6-10 present a detailed breakdown of the annualized
costs for the three model plants. Mote that two items—utilities and
capital recovery—account for 70 to 80 percent of the total costs.
6.3 COST EFFECTIVENESS
The cost of controlling NOX emissions can be related to the quantity
of pollutant removed from the exhaust gas stream by using the annualized
costs as a basis. Because costs tend to follow the 0.6 Power Rule (so-called
"economies of scale"), the cost-effectiveness of the regulation is more
attractive to larger plants. The estimated quantity of NOX controlled by
the MSPS requirements is as follows:
6-16
-------
TABLE 6-8. AWJUALIZED COST SUMMARY FOR CATALYTIC
REDUCTION [MODEL PLANT WITH A CAPACITY
OF 181 Mg/day (200 tons/day)]
(in January 1983 dollars)
Cost element
Cost,
$1000
A. DIRECT OPERATING COSTS
I. Utilities
a. Natural gas (net of recovered heat) at $4.GO/MBtu
2. Operating Labor
a. Direct ($15/man-hour)
b. Supervision (2Q% x direct labor)
3. Maintenance and Supplies (4% x Capital Cost)
a. Labor and material .
b. Supplies
B. CAPITAL CHARGES
1. Overhead
a. Plant (50% x A2 and A3 above)
b. Payroll (20% x A2 above)
2. Fixed Costs
a. Capital recovery (13.5% x Capital Cost)
b. Insurance, taxes, and G&A (4% x Capital Cost)
TOTAL
210
11
2
38
25
">
0
124
38
451
6-17
-------
TABLE 6-9. ANNUALIZED COST SUMMARY FOR CATALYTIC
REDUCTION [MODEL PLANT WITH A CAPACITY
OF 454 Mg/day (500 tons/day)]
(in January 1983 dollars)
Cost element
Cost,
$1000
A. DIRECT OPERATING COSTS
1. Utilities
a. Natural gas (net of recovered heat) at$4.00/MBtu
2. Operating Labor
a. Direct ($15/man-hour)
b. Supervision (20% x direct labor)
3. Maintenance and Supplies (4% x Capital Cost)
a. Labor and material
b. Supplies
530
11
2
65
CAPITAL CHARGES
1. Overhead
a. Plant (50% x A2 and A3 above)
b. Payroll (20% x A2 above)
2. Fixed Costs
a. Capital recovery (13.5? x Capital Cost)
b. Insurance, taxes, and G&A (4% x Capital Cost)
39
3
214
65
C. TOTAL
929
6-18
-------
TABLE 6-10. ANNUALIZED COST SUMMARY FOR CATALYTIC
REDUCTION [MODEL PLANT WITH A CAPACITY
OF 907 Mg/day (1000 tons/day)]
(in January 1983 dollars)
Cost element
Cost,
$1000
A.
3.
DIRECT OPERATING COSTS
1. Utilities
a. Natural gas (net of recovered heat) at $4.00/MBtu
2. Operating Labor
a. Direct ($15/man-hour)
b. Supervision (20% x direct labor)
3. Maintenance and Supplies (4% x Capital Cost)
a. Labor and material
b. Supplies
CAPITAL CHARGES
1. Overhead
a.
b.
Plant (50% x A2 and A3 above)
Payroll (20% x A2 above)
2. Fixed Costs
a.
b.
Capital recovery (13.5% x Capital Cost)
Insurance, taxes, and GV\ (4% x Capital Cost)
C. TOTAL
1050
11
2
99
56
3
325
99
1645
6-19
-------
Plant size. Mg/day NOX removed, Hg/yr
181 391
454 977
907 1955
These quantities assume that uncontrolled NOX emissions are about
0.0075 kg/kg of acid produced (15 Ib/ton of acid produced), which is
equivalent to an NOX concentration of 1000 ppm in the exhaust gas. The
required reduction to 200 ppm would remove 0.0060 kg/kg (12 Ib/ton) of acid
produced. The cost effectiveness of each control alternative is shown in
Table 6-11. The cost effectiveness of extended absorption ranges from a
cost savings of $46 per megagram for a 970 Mg/D plant to a cost of S258
per megagram from a 181 Mg/D plant. For catalytic reduction, the cost
effectiveness ranges from S841 per megagram for a 970 Mg/D plant to $1,153
per megagram for a 181 Mg/D plant. Plants with capacities greater than
about 650 Mg/day actually benefit financially by using extended absorption
because the acid credits exceed the control costs. However, the amount
of credit is sensitive to the recovery efficiency at each installation
and to the value placed upon the recovered acid. Overall, the cost
effectiveness figures are in the reasonable range. Figure 6-5 is a
graphical presentation of the cost effectiveness data.
6.4 REFERENCES
1. Peters, M. S., and K. D. Timmerhaus. Plant Design and Economics for
Chemical Engineers. 3rd Ed. McGraw-Hill, New York. 1980.
2. Means, R. S. Building Construction Cost Data, 1983.
6-20
-------
TABLE 6-11. COST EFFECTIVENESS RATIOS FOR
MODEL PLANTS USING EXTENDED ABSORPTION AND
CATALYTIC REDUCTION CONTROLS
(in January 1983 dollars)
Control
Method
Extended Absorption
Extended Absorption
Extended Absorption
Catalytic Reduction
Catalytic Reduction
Catalytic Reduction
Plant Size
Annualized
Cost
Mg/day (tons/day) (SlOOO/yr]
181 (200) 101
454 (500) 52
907 (1000) (90)
181 (200) 451
454 (500) 929
907 (1000) 1,645
NOX Cost
Removed Effectiveness
(Mg/yr) (S/Mg NOX)
391
977
1,955
391
977
1,955
258
53
(46)a
1,153
951
841
a Value of product recovered is greater than the control cost
resulting in a saving.
6-21
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 REPORTNO. 2. ""
EPA-450/3-84-011
4. TITLE AND SUBTITLE
Review of New Source Performance Standards for Nitric
Acid Plants
7 AUTHOR(S)
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Office of Air Quality Planning and Standards
U.S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
12. SPONSORING AGENCY NAME AND ADDRESS
DAA for Air Quality Planning and Standards
Office of Air and Radiation
U.S. Environmental Protection Agency
RTP. N.C. 27711
3. RECIPIENT'S ACCESSION- NO.
5. REPORT DATE
,. .. Aoril 19.84
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
1 1 . CONTRACT/GRANT NO.
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA 200/04
15. SUPPLEMENTARY NOTES ~ —
This report reviews the current New Source Performance Standards for Nitric Acid
__, — ,
applicable control technology, and the ability of plants to meet the current
standards.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTOR
b.lDENTIFIERS/OPEN ENDED TERMS
c. COS AT I Field/Groi
Air Pollution
Nitric Acid Plants
Nitrogen Oxides
Standards of Performance
Pollution Control
Air Pollution Control
13B
Release Unlimited
19. SECURITY CLASS (This Reportj
Unclassified
21. NO. OF PAGES
70
iO SECURITY CLASS f This page)
Unclassified
22. PRICE
rorm 2220-1 (9-73)
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