.,   0                        V66/3-
            United States      Office of Air Quality        EPA-450/S-84-011
            Environmental Protection  Planning and Standards      April 1984
            A9encV        Research Triangle Park NC 27711
            Air
&EPA      Review of New
            Source  Performance
            Standards for Nitric
            Acid Plants

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                                    EPA-450/3-84-011
Review of New Source Performance
   Standards for Nitric Acid Plants
            Emissions Standards and Engineering Division
             U.S. ENVIRONMENTAL PROTECTION AGENCY
                  Office of Air and Radiation
             Office of Air Quality Planning and Standards
             Research Triangle Park, North Carolina 27711

                      April 1984

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This report has been reviewed by the Emission Standards and Engineering Division of the Office of Air
Quality Planning and Standards, EPA, and  approved for publication. Mention of trade names or
commercial products is not intended to constitute endorsement or recommendation for use. Copies of
this report are available through the Library Services Office (MD-35), U.S. Environmental Protection
Agency, Research Triangle Park, N.C.  27711, or from the National Technical Information Services,
5285  Port Royal Road, Springfield, Virginia  22161.

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                              TABLE OF CONTENTS

                                                                Page

 LIST OF ILLUSTRATIONS                                          v

 LIST OF TABLES                                                 vi

 1.  EXECUTIVE SUMMARY                                          ±_i

 1.1  BEST DEMONSTRATED CONTROL TECHNOLOGY                      1-1
 1.2  ECONOMIC CONSIDERATIONS AFFECTING THE NSPS                1-2
 1.3  STRONG NITRIC ACID PLANTS                                 !_2

 2.   THE NITRIC ACID MANUFACTURING INDUSTRY                   2-1

 2.1  INTRODUCTION                                             2 1
 2.2  BACKGROUND INFORMATION                                   2-1

      2.2.1  Single Pressure Process                           2-4
      2.2.2  Dual  Pressure Process                             2-8
      2.2.3  Strong Nitric Acid  Production                     2-8

 2.3  EMISSIONS FROM NITRIC ACID PLANTS                         2-10
 2.4  INDUSTRY CHARACTERIZATION                                 2-11

      2.4.1  Geographic  Distribution                           2-11
      2.4.2  Production                                         2-12
      2.4.3  Trends                                             2-12

 2.5  SELECTION OF  NITRIC  ACID PLANTS  FOR  NSPS  CONTROL          2-12
 2.6  REFERENCES                                                2-13

 3.    CURRENT  STANDARDS  FOR  NITRIC ACID PLANTS                  3-1

 3.1   FACILITIES AFFECTED                                       3 1
 3.2   CONTROLLED POLLUTANTS  AND  EMISSION LEVELS                 3-1
 3.3   TESTING  AND MONITORING REQUIREMENTS                       3_2

     3.3.1  Testing Requirements                               3_2
     3.3.2  Monitoring  Requirements                            3-2

4.   STATUS OF CONTROL TECHNOLOGY                              4_!

4.1  EXTENDED ABSORPTION                                       4 i
4.2  CATALYTIC REDUCTION                                       4 5
4.3  CAUSTIC SCRUBBING                                         4 o
4.4  REFERENCES                                                4 8
                                   m

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                     TABLE OF CONTENTS (cont'd)

                                                            Page

5.   COMPLIANCE TEST RESULTS                                5-1

5.1  ANALYSIS OF NSPS COMPLIANCE TEST RESULTS               5-1
5.2  ANALYSIS OF NOX MONITORING RESULTS                     5-3
5.3  STATUS OF NOX EMISSIONS MONITORS                       5-6
5.4  REFERENCES                                             5-6

6.   COST ANALYSIS                                          6-1

6.1  EXTENDED ABSORPTION PROCESS                            6-1

     6.1.1  Capital Costs                                   6-1
     6.1.2  Annualized Costs                                6-2

6.2  CATALYTIC REDUCTION                                    6-15

     6.2.1  Capital Costs                                   6-15
     6.2.2  Annualized Costs                                6-15

6.3  COST EFFECTIVENESS
6.4  REFERENCES
                                    IV

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                          LIST OF ILLUSTRATIONS

Figure Number                                                    page

     2-1         Single Pressure Nitric Acid Manufacturing       2-7
                 Process

     2-2         Dual  Pressure Nitric  Acid Manufacturing         2-9
                 Process

     4-1         Extended  Absorption System Using  Second         4-3
                 Absorber  For NOX Control

     4-2         Extended  Absorption System Uisng  One  Large       4-4
                 Absorber  For NOX Control

     4-3         Acid  Plant  Incorporating  Catalytic  Reduction     4-6
                 For NOX Abatement

     4-4         Schematic Of Nitric Acid  Plant  Incorporating     4-9
                 Caustic Scrubbing For  NOX  Control

     6-l          Secondary Absorber Tower  Input  and  Output for    6-3
                 a 454 Mg/day  (500 TPD) Nitric Acid  Plant

     6-2          Schematic of  Extended  Absorption  System          6-4

     6-3          Capital Cost of  Extended Absorption System       6-8
                 for Nitric Acid  Plant

     6-4          Annualized Costs of Extended Absorption          6-14
                 System For Nitric Acid Plant

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                              LIST OF TABLES

Table Number                                                     Page

   2-1           Nitric Acid Plants Completed Since              2-5
                 Promulgation of the NSPS

   5-1           Compliance Test Results For Nitric Acid         5-2
                 Plants Subject to the NSPS Since the
                 1979 Review

   5-2           Summary of NOX Monitoring Data For Nitric       5-4
                 Acid Plants Subject to the NSPS

   6-1           Capital Cost Summary For An Extended            6-5
                 Absorption System [Plant With a Capacity
                 of 181 Mg/day (200 tons/day)]

   6-2           Capital Cost Summary For An Extended            6-6
                 Absorption System [Plant With a Capacity
                 of 454 Mg/day (500 tons/day)]

   6-3           Capital Cost Summary For An Extended            6-7
                 Absorption System [Plant With a Capacity
                 of 908 Mg/day (1,000 tons/day)]

   6-4           Nitric Acid Prices                              6-10

   6-5           Annualized Cost Summary For An Extended         6-11
                 Absorption System [Plant With a Capacity
                 of 181 Mg/day (200 tons/day)]

   6-6           Annualized Cost Summary For An Extended         6-12
                 Absorption System [Plant With a Capacity
                 of 454 Mg/day (500 tons/day)]

   6-7           Annualized Cost Summary For An Extended         6-13
                 Absorption System [Plant With a Capacity
                 of 907 Mg/day (1,000 tons/day)]

   6-8           Annualized Cost Summary For Catalytic           6-17
                 Reduction [Model Plant With a Capacity
                 of 181 Mg/day (200 tons/day)]

   6-9           Annualized Cost Summary For Catalytic           6-18
                 Reduction [Model Plant With a Capacity
                 of 454 Mg/day (500 tons/day)]
                                    VI

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                        LIST OF TABLES (Cont'd)

Table Number

   6-10          Annualized Cost Summary For Catalytic
                 Reduction [Model  Plant With a Capacity
                 of 907  Mg/day (1,000 tons/day)]

   6-11          Cost Effectiveness Ratios  For Model  Plants       6-21
                 Using Extended Absorption  and Catalytic
                 Reduction Controls
                                   vn

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                          1.  EXECUTIVE SUMMARY

     The new source performance standards (NSPS) for nitric acid plants
were promulgated by the Environmental Protection Agency (EPA) on December 23,
1971.  The standards affect nitric acid production units which commenced
construction or modification after August 17, 1971.  A nitric acid
production unit is any facility producing weak nitric acid (30 to 70
percent in strength) by either the pressure or atmospheric pressure
process.  The NSPS limits emissions of nitrogen oxides (NOX).
     A review of the nitric acid plant standard was previously conducted
in 1979; however, no revisions to the NSPS were made as a result of the
1979 review.
     The objective of this report is to again review the USPS for nitric
acid plants.  The following paragraphs summarize the findings of this
second review.
1.1  BEST DEMONSTRATED CONTROL TECHNOLOGY
     The control methods used by nitric acid units subject to the NSPS
are extended absorption, catalytic reduction, and chilled absorption with
caustic scrubbing.  Catalytic reduction was used as the basis for the
NSPS since, at the time of the NSPS development, no other NOX control
methods had been demonstrated to achieve the NSPS.  Since promulgation of
the NSPS, the catalytic reduction process has been largely supplanted by
the extended absorption process as the control method of choice for
achieving the NSPS due to increasing fuel  costs.  None of the units built
since 1977 are designed with catalytic reduction.  The capability of
extended absorption and chilled absorption with caustic scrubbing in
achieving the NSPS was indicated by information and data obtained during
the 1979 review.
     Compliance test results for the 10 facilities subject to the NSPS
which have started operation since the 1979 review indicated that all
have achieved the MSPS with the exception of one extended absorption

                                   1-1

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 unit.   This  unit  has never been operated except for a 2-day startup period
 during  which time the  unit was compliance  tested and shut down.  It is
 installed  as a  standby unit  for ammunition production.
 1.2  ECONOMIC CONSIDERATIONS AFFECTING THE NSPS
     The cost effectiveness  of achieving the NSPS was estimated for the
 two  most prevalent control systems, extended absorption and catalytic
 reduction, on nitric acid plant sizes of 181,454 and 907 Mg/D (200, 500,
 and  1,000  TPD).   The cost effectiveness of extended absorption ranges
 from a cost  savings of $46 per megagram for a 970 Mg/D plant ($42 per
 ton  for a  1,000 TPD plant) to a cost of $258 per megagram for a 181 Mg/D
 plant ($235  per ton for a 200 TPD plant).  For catalytic reduction, the
 cost effectiveness ranges from $841 per megagram for a  970  Mg/D plant
 ($760 per  ton for a 1,000 TPD plant) to $1,153 per megagram for a
 181  Mg/D plant ($1,050 per ton for a 200  TPD plant).
     Since the MSPS was proposed,  29 nitric acid units  have started
 operation.   The growth rate in terms of nitric acid production  average
 1.7  percent per year between  1971  and 1982.  The actual  average rate of
 start-up between 1971  and 1982 has been between two and  three  units per
year.
 1.3  STRONG NITRIC ACID PLANTS
     The NSPS does not apply  to the various processes  used  to  produce
 strong acid.   The rationale for excluding strong acid  plants  from the
NSPS at the time it was developed  was that  emissions from these  strong
acid plants are small,  about  the  level  of the MSPS,  and  only one  strong
acid process  was in  operation.   This review has found two strong  acid
units which have started operation since  1971,  and  the  reported NOX
emissions  from these  strong acid  plants are below  the level of  the  NSPS.
                                   1-2

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                 2.   THE NITRIC ACID MANUFACTURING INDUSTRY

 2.1   INTRODUCTION
      The  United  States  Environmental  Protection  Agency  (EPA)  proposed  new
 source performance  standards  (NSPS)  for  nitric acid  plants under  Section 111
 of the Clean  Air Act on August 17,  1971  (36  FR 15704).  These  regulations
 were  promulgated on  December  23,  1971  (36  FR 24875).  The  regulation
 applied to  any nitric acid  production  facility producing weak  nitric
 acid,  the construction  or modification of  which  commenced  after August 17,
 1971.
     The Clean Air Act  Amendments of  1977  require that  the Administrator
 of the EPA  review and,  if appropriate, revise established  standards of
 performance for  new  stationary  sources at  least every 4 years.  The NSPS
 was previously reviewed  in  1979; no changes  in the NSPS were made as a
 result of the 1979 review.  The purpose of this report  is  to review and
 assess  the need  for  revision of the existing standards of  nitric acid
 plants  based on  developments that have occurred since the last review or
 are expected to  occur within the nitric acid manufacturing industry.
 The information  presented in this report was obtained from reference
 literature, discussions with industry representatives, control equipment
 vendors, EPA regional offices, and State agencies.
 2.2  BACKGROUND  INFORMAT ION 1
     Nitric acid  is manufactured in  the U.S.  by the  high temperature
catalytic  oxidation of ammonia.  The essential  components  of an ammonia
oxidation  nitric  acid plant  are:
     1.  Converter  or oxidation section where the ammonia  vapor and  air
         are mixed  and reacted catalytically  to oxidize  the ammonia.
     2.  Cooler-Condenser section  where the nitroaen  dioxide  is produced
         by  cooling  the  reaction gases and  weak nitric acid is formed.
     3. Absorber section where the  cool  nitrogen  dioxide  is  absorbed  in
        water to form nitric  acid.
                                   2-1

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In the first step of this process, one volume of anhydrous ammonia is
mixed with nine volumes of preheated air and passed through a multi-
layered, silk fine platinum-rhodium gauze catalyst at 750° to 800°C
(1,380° to 1,470°F).  Under these conditions, the oxidation of ammonia to
nitric oxide proceeds in an exothermic reaction with a 95 percent yield:
                    4NH3 + 502 > 4NO + 6H20                          (1)
     The second step involves the oxidation of the nitric oxide to nitrogen
dioxide and its liquid dimer, nitrogen tetroxide:
                    2NO + 02 > 2N02 > ^04                           (2)
The forward rate of reaction (2), which is rather slow compared with
reaction (1), is favored at lower temperatures and higher pressures.
Hence, reaction (2) is always carried out after cooling the gas to 388C
(100°F) or less and, depending on the process design, at pressures up to
500 kilopascals (kPa) (73 psig).
     In the final  step, the nitrogen dioxide/dimer mixture is cooled
further and passed to an absorber where it reacts with water to produce
an aqueous solution of 50 to 60 percent nitric acid, the concentration
depending on the temperature, pressure, number of absorption stages, and
concentration of the nitrogen dioxide entering the absorber:
                    31102 + H20 + 2HN03 + MO                          (3)
     This reaction is also favored by low temperature and high pressure,
because the gases involved are more soluble at lower temperatures and
absorption results in a reduction in volume.  In fact, some processes
utilize the low temperature/high pressure conditions to increase yields.
     The formation of nitric acid in Equation (3) involves the
disproportionation of nitrogen dioxide to form two moles of nitric acid
for every mole of nitric oxide.  In order to reoxidize the nitric oxide
during absorption, secondary air (also known as bleacher air) is introduced
into the absorber along with the nitrogen dioxide.  However, the reaction
to form nitric acid is never quite complete—the overall process is
95 percent efficient, so that a small quantity of nitrogen oxides, fJOx
OJ02 and NO), is inevitably present in the waste gas discharged from the
absorption column.  The NOX in these waste gases is the target for air
pollution regulations and control.
                                   2-2

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      Acid product  is  withdrawn  from the  bottom of  the  tower  in  concentrations
 of 55 to 65  percent.   The  air entering the  bottom  of the  tower  serves  to
 strip N02 from  the  product and  to  supply oxygen  for reoxidizing  the HO
 formed in making nitric  acid  (Equation 3).
      The oxidation  and absorption  operations  can be carried  out  at low
 pressures [100  kPa  (14.5 psi)], medium pressures [400  to  800 kPa  (58 to
 116  psi)], or high  pressures  [1,000 to 1,200  kPa (145  to  174 psi)].  Both
 operations may  be at  the same pressure or different pressures.
      Before  corrosion-resistant materials were developed  (precluding the
 use  of high  pressures) the ammonia  oxidation  and absorption operations
 were carried out at essentially atmospheric pressure.  The advantages
 over higher  pressure  processes were  longer catalyst life  (about 6 months)
 and  increased efficiency of ammonia  combustion.  However, because of the
 low  absorption  and NO  oxidation rates, much more absorption volume was
 required, and several  large towers were  placed in series.
      Combination pressure  plants carry out the ammonia oxidation process
 at low or medium pressure  and the absorption  step at medium or high
 pressure.  The  increased pressure for the oxidation reaction shortens the
 catalyst's lifetime (1 to  2 months) and  lowers the ammonia oxidation
 conversion efficiency.  Thus, lower pressures  in the oxidation  process
 are  preferred.   On the other hand,  higher pressures in  the absorption
 tower  increase  the absorption efficiency  and reduce fJOx levels  in the
 tail gas.  The  advantages of higher absorber pressures  must be  weighed
 against  the cost of pressure vessels and  compressors.
     The choice  of which  combination of pressures to use is very site
 specific and is  governed  by the  economic  tradeoffs  such as costs of raw
materials, energy and equipment,  and process efficiency.   In  the 1960's,
combination low  pressure  oxidation/medium pressure  absorption and single
pressure [400 to 800 kPa  (58 to  116 psi)] plants were preferred.   Since
the 1970's, the  trend has been  toward medium pressure oxidation/high
pressure absorption  plants  in  Europe and  single pressure  [400 to  800  kPa
(58 to 116 psi)] plants in  the U.S.
                                   2-3

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     The two types of weak nitric acid production processes in use in  new
U.S. plants, i.e., single pressure and dual  pressure process,  are described
in the following sections.  Table 2-1  lists  all  of the new and modified
nitric acid plants subject to NSPS, together with their capacities and
the production and NOX abatement processes used.
2.2.1  Single Pressure Process
     In the single pressure process, both the oxidation and absorption
are carried out at the same pressure—either low (atmospheric) or medium
pressures of 400 to 800 kPa (60 to 120 psig).  Single pressure plants  are
the most common type in the U.S.  Figure 2-1 is a simplified flow diagram
of a single pressure process.  A medium pressure process will  be described
in the following paragraphs.
     Air is compressed, filtered, and  preheated to about 300°C (592°F) by
passing through a heat exchanger.  The air is then mixed with  anhydrous
ammonia, previously vaporized in a continuous-steam evaporator.  The
resulting mixture, which contains about 10 percent ammonia by  volume,  is
passed through the reactor.  The reactor contains a platinum-rhodium
(2 to 10 percent rhodium) wire-gauze catalyst (e.g., 30 mesh and 75 mm
diameter wire, packed in layers of 10  to 30  sheets) so that the gas
travels downward through the gauze sheets.  Catalyst operating temperature
is about 750°C (1382°F).
     The hot nitrogen oxides and excess air  mixture (about 10  percent
nitrogen oxides) from the reactor are  partially cooled in a heat exchanger
and further cooled in a water cooler.   The cooled gas is introduced into
a stainless-steel absorption tower with additional air for the further
oxidation of nitrous oxide to nitrogen dioxide.  Small quantities of
water are added to hydrate the nitrogen dioxide and also to scrub the
gases.  The overhead gas from the tower is reheated by feed/effluent heat
exchangers and then expanded through a power recovery turbine/compressor
used to supply the reaction air.*  The bottom of the tower yields nitric
*In those plants using catalytic reduction as NOX abatement method,  the
tail gas is first passed through the catalytic reduction system and  then
expanded through a power recovery turbine/compressor used to supply  the
reaction air.
                                   2-4

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                                Table 2-1.  NITRIC ACID PLANTS COMPLETED  SINCE  PROMULGATION OF THE NSPS
r-o
i
en
Company
Allied Chemical Corp.
Monsanto Textile Co.
Nitram, Inc.
Kaiser Aluminum & Chem.
Columbian Nitrogen
Mississippi Chemical

U.S. Army
CF Industries
IMC - Dixie Chemical
Rubicon Chemical Inc.
Allied Chemical Corp.
Agrico Chemical Co.

Air Products & Chemical
Dupont Co.
Union Oil Co. of Calif.
Valley Nitrogen
Plant Location
Newell , PA
Escambia City, FL
Tampa, FL
Savannah, GA
Augusta, GA
Yazoo City, MS

Holston, TN
Donaldsonville, LA
Sterlington, LA
Geismar, LA
Geismar, LA
Catoosa, OK

Pasadena, TX
Victoria, TX
Brea, CA
Fresno, CA
Year
Completed
1975
1977
1976
1976
1977
1977
1973
1976
1977
1976
1976
1978
1975
1979
1976
1977
1977
1977
Plant
Design Capacity
(100X HN03)
Mg/day (tons/day) Process Design
164
819
310
450
819
910
328
285
470
200
320
500
570
570
289
918
137
180
(180)
(900)
(350)
(500)
(900)
(1000)
(360)
(315)
(520)
(220)
(350)
(550)
(630)
(630)
(318)
( 1000 )
(150)
(200)
Single Pressure
Dual Pressure
Single Pressure
Single Pressure
Single Pressure
Dual Pressure
Single Pressure
Dual Pressure
Dual Pressure
Single Pressure
Single Pressure
Single Pressure
Single Pressure

Single Pressure
Single Pressure
Single Pressure
Single Pressure
Emission Control System
Catalytic Reduction
— — _
Catlytic Reduction
Extended Absorption
Catalytic Reduction
Extended Absorption
Extended Absorption
Extended Absorption
Extended Absorption
Extended Absorption
Catalytic Reduction
Extended Absorption
Chilled Absorption &
Caustic Scrubbing
Catal "! ii Reduction
i < < • \.jsorption
Catalytic Reduction
Cat.ilytic Reduction

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                             Table  2-1.   NITRIC ACID PLANTS COMPLETED SINCE PROMULGATION OF THE NSPS  (Cont'd)
ro
i
c-i
           Company
Plant Location
    Year
Completed
       Plant
   Design Capacity
    (100% HNOa)
Mg/day (tons/day)
Process Design    Emission Control System
J.R. Simplot Co.
Chevron Chemical
Apache Power Co.
American Cyanamid
USS Agri -Chemical
Gulf Oil Chemical
Chevron Chemical
Co.

Co.
s
s Co.
Co.
Bison Nitrogen Products
N-ReN Southwest,
Inc.
Badger Army Ammunition
N-ReN Corporation
Pocatello, ID
Kennewick, WA
Benson,
Hannibal
Crystal
Jayhawk,
AZ
, MO
City, MO
KS
Fort Madison, IA
Woodward
Carlsbad
Baraboo,
, OK
, NM
WI
East Dubuque, IL
1977
1977
1978
1978
1979
1979
1981
1978
1975
1981
1979
50
500
270
320
500
910
500
250
180
360
200
(53)
(550)
(300)
(350)
(550)
(1,000)
(550)
(272)
(195)
(400)
(220)
Singl
Singl
Dual
Singl

Singl
Singl
Singl

Dual
Singl
e Pressure
e Pressure
Pressure
e
-
e
e
e
-
Pressure
—
Pressure
Pressure
Pressure
--
Pressure
e
Pressure
Catalytic Reduction
Extended Absorption
Extended
Extended
Extended
Extended
Extended
Extended
Catalytic
Extended
Extended
Absorption
Absorption
Absorption
Absorption
Absorption
Absorption
Reduction
Absorption
Absorption

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   Ammonia (Anyhdrous)
                         o
                         a
                         a

                         ai
                                                                               Waste Gases to Power Recovery

                                                                                  and Tall Gas Treatment
                                                                                     Water
         Reactor
Air
          Compressor
Filter
                               Cooler
                                                                     Weak Acid
                                                             Air
                                                     €
                                                     o
                                                     
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acid of 55 to 65 percent strength.  Nineteen of the twenty-nine U.S.
nitric acid plants subject to NSPS employ a single pressure process.
2.2.2  Dual Pressure Process
     In order to obtain the benefits of increased absorption (with greater
product yield) and reduced NOX emissions, five dual pressure plants
subject to NSPS have been built in the U.S.
     A simplified process flow diagram for a dual pressure plant is shown
in Figure 2-2.  In the 'Jhde version of this process,  liquid ammonia is
vaporized by steam, heated, and filtered before being mixed with air from
the air/nitrous oxide compressor at from 300 to 500 kPa  (°^3 to 5 atm).
The ammonia/air mixture is catalytically oxidized in  the reactor with heat
recovery by an integral waste heat boiler to generate steam for use in
the turbine-driven compressor.  The combustion gases  are further cooled
by tail gas heat exchange and water cooling before compression to the
absorber pressure of 800 to 1400 kPa M to 14 atm).   The absorption
tower is internally water-cooled to increase absorption  by water.  Nitric
acid up to 70  percent concentration is withdrawn  from the bottom of the
column and degassed with the air feed  to remove unconverted NO before
being sent to  storage.  The air/NO mixture is  combined with reactor
effluent to form the absorber feed.  High yields  of up to 96 percent
conversion can be obtained by this process.
2.2.3  Strong  Nitric Acid Production
     The NSPS  does not apply to the various processes used to produce
strong acid (95-99 percent strength) by extraction  or evaporation of weak
acid, or by the direct strong acid process.  For  the  most part,  nitric
acid is manufactured and consumed  at concentrations of about 60  percent.
But, concentrated (90  percent or more)  nitric  acid  is needed for the
production of  chemicals such as isocyanates and nitrobenzene.3   The
rationale for  excluding strong acid plants from the NSPS at the  time it
was developed  was that, in comparison  to the NOX  emissions from  weak acid
plants, emissions from the strong  acid  plants  are relatively minor and
only one strong acid process was in operation.4

                                   2-8

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ro
i
             Ammonia (Anyhdrous)
                                 b
                                 Q.
        Air.
                  Compressor
                                                    Reactor
                                          Filter
                                                                                      Waste Oases to Power Recovery

                                                                                          and Tall Gas Treatment
                                                                       Compressor
Cooler
                                                                  NO/NO,
                                                                              Weak Acid
                                                                    Air
                                                                                             Water
                      3
                      o
                      
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     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

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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

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 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

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                    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

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                                                                                                    Tail Gas
-pi
OJ
Ammon i a
N-










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I
















Compressor







^


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>




f
/"~^\




V

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^

i












Converter



k
•J
^




\
^












f

Heat












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/ \










^~
f
Absorber












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1
1
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I

1— A UCTIIvJCvJ
Absorber
f ""1
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' 1
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c Process
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1 IT
r Weak Acid

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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

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                                                                                    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

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 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

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                         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

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                              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

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                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

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               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

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               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

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               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

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                   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

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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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