Enclosure 5a

Page 1 of 22

EPA Information Collection Request for Nitric Acid NSPS (Subpart G)

Plant Data

Facility name PCS Geismar

Facility owner (ultimate parent owner) PCS Nitrogen Fertilizer L.P.

Plant Location - Address Hwy 30 & Hwy 3115

Latitude/Longitude for Plant N30.2 / W91.0

Describe location of latitude/longitude PCS Geismar

City, State, ZIP code 70734

Year plant began operation 1965

Information for Each Nitric Acid Production Line

(change names as needed and use the same names in the Excel spreadsheet)

Train III Train IV Train V

Year line began operation

1978

1970 in Gibbstown,

NJ moved to Geismar, 

LA in 1996 1999

Production Rate (Tons/Day of 

100% Acid) 650 550 1600

Production Rate Range (Tons/Day of 

100% Acid) 400-650 400-550 1000-1750

Subject to Subpart G? Yes No Yes

Process Type (high/low pressure) Mono-high pressure Mono-high pressure Dual Pressure

Oxidation pressure (psia) 160 150 75

Absorption pressure (psia) 145 140 160

% Acid strength Typically Produced 65 65 65

Operating Hours/Year Train III Train IV Train V

2008 5639 7349 6821

2007 5991 7469 8554

2006 1140 5340 8317

Control Technology 

(list as many as applicable)

Extended absorption

(refrigerated)

& SCR NSCR SCR

% Control Efficiency (based on most 

recent compliance test)

Train III Train IV Train V

NOX 97% 96% 97.5%

NO 96%
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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NO2 100%

Permit Limits for Each Nitric Acid Production Line

(Fill in all applicable rows)

Train III Train IV Train V

NOX Emissions (tpy) 260.98 195.00 113.26

NOX Emissions (lb/hr) 59.58 (avg)

81.25 (max)

44.52 (avg)

135.42 (max)

25.86 (avg)

200.02 (max)

NOX Emissions (lb/ton of 100% 

acid) 3.0 5.95 3.0

Permitted NOX control efficiency, if 

applicable N/A N/A N/A

If your permit includes limits for 

other pollutants, please include as 

much detail as possible below:

Train III Train IV Train V

Ammonia average (lb/hr) 1.1 11.8 3.49

Ammonia maximum (lb/hr) 1.32 13.06 17.43

Ammonia (TPY) 4.82 51.68 15.27

CO average (lb/hr) - 104.86 -

CO maximum (lb/hr) - 125.84 -

CO (TPY) - 459.30 -

VOC average (lb/hr) - 0.24 -

VOC maximum (lb/hr) - 0.29 -

VOC (TPY) - 1.07 -

SO2 average (lb/hr) - 0.03 -

SO2 maximum (lb/hr) - 0.03 -

SO2 (TPY) - 0.12 -

PM1 average (lb/hr) - 0.34 -

PM1 maximum (lb/hr) - 0.40 -

PM1 (TPY) - 1.48 -

Nitric Acid average (lb/hr) - - .01

Nitric Acid maximum (lb/hr) - - .01

Nitric Acid (TPY) - - .03
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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For each control device, please provide the key design parameters 

Extended Absorption (Train III)

Length

The absorption column in Train III is 167’ tall with the top 72’ of the 

tower being extended absorption section

Design Information

(gal/ 10 3acfm, etc)

The top 72 feet of the absorption column is considered the extended 

absorption section. It is refrigerated to approximately 40 F to enhance 

NO2 absorption. The de-mineralized feed water for the column is fed 

into the top of the extended absorption section at a rate of 20-40 GPM. 

This water flows down the 14 trays of the extended section of the 

absorption column then into the conventional section of the absorption 

section of the tower which has 20 trays.

Operation and Maintenance required

(Last 10 years)

-The refrigeration compressor that chills extended absorption section was

completely replaced in 1999 at a cost of $390,000.

-An internal inspection of the extended absorption column was 

completed in 2009 at a cost of $85,000.

Year absorption capacity was added The extended absorption was original to the plant design in 1978.

If you use an additive in your absorption column: NONE USED AT PCS Nitrogen, Geismar

Name of additive (i.e., hydrogen 

peroxide) -

Concentration of additive (%): -

Explain the process: -

Addition rate (gallons per hour): -

Ratio of additive to water: -

SCR (Train III)

Type of Catalyst Shell CRI- (low pressure, located downstream of expander)

Is Catalyst New or Regenerated? New

Catalyst Life (Design/Actual) 4 years /still on first charge

Catalyst Volume (m

3

) 12.6

Flow rate (scfm) 45,000

Ammonia injection rate (lb/hr) 242 

Operation and Maintenance required

(Last 10 years) None (new in 2007)

Year began operation 2007
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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SCR (Train V)

Type of Catalyst Grand Paroisse

Is Catalyst New or Regenerated? New (installed as first charge after plant construction in 1999)

Catalyst Life (Design/Actual) 10 years / 11years

Catalyst Volume (m3) 6

Flow rate (scfm) 140,000

Ammonia injection rate (lb/hr) 200 to 400 (winter vs. summer)

Operation and Maintenance required 

(Last 10 years) Added 4 drums of catalyst at a cost of $60,000 USD

Year began operation 1999

For each control device, please provide the key design parameters

NSCR (Train IV)

Reductant used (methane, H2, etc) Methane

Rate of reductant used 12,000. lbs/hr

Type of catalyst Precious metal on honeycomb monolith substrate (EnProSol)

Catalyst Volume (m

3

) 1.02

Flow rate (scfm) 42,000

Is Catalyst New or Regenerated? New Catalyst

Catalyst Life (Design/Actual) 4 / 5

Operation and Maintenance required 

(Last 10 years)

Catalyst replaced every 4 years ($250,000 per catalyst charge + $20,000. 

for installation)

Year began operation 1970 (original to plant)
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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Cost Information by Control Technology

Production

Line

Pollutant 

Controlled

Control 

Technology

Capital

(Yr of Cost basis)

Annual O & M

(Yr of cost basis)

Train III NOx Extended 

Absorption

(refrigerated)

$ 3,000,000.

(2010 approx1) Electricity= $ 76,000./yr

Maintenance cost= $ 15,000./yr

TOYAL = $ 91,000./yr

Train III NOx SCR $ 1,235,000. 

(project cost in 2007)

Maintenance= $ 18,500./yr

Ammonia2= $ 25,000./yr

SCR Catalyst3= $ 71,735./yr

TOTAL= $ 115,260./YR

Train IV NOx NSCR $ 1,495,000.

(2010 approx1)

Maintenance= $ 22,425./yr

Methane4= $ 1,300,000./yr

NSCR Catalyst5= $ 67,600./yr

TOTAL = $ 1,390,000./YR

Train V NOx SCR 1,820,000.

(2010 approx1)

Maintenance= $27,300./yr

Ammonia= $ 315,000./yr

SCR Catalyst6= $ 54,300./yr

TOTAL = $ 396,583./YR

Please provide additional cost information, comments, or notes below:

Notes:

1. Cost estimate determine from past projects +/- 50 %

2. Ammonia price of $300/ ton 

3. SCR catalyst life of 4 years (CRI-Guarantee)

4. Natural gas price of $5/mmbtu

5. NSCR Catalyst life of 4 years

6. SCR catalyst life of 10 years (GP design)
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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Continuous Emission Monitoring Systems

CEMS Information-Train III

? Plant CEMS data recorded 

concurrent with test runs (i.e., 

concentration, etc.).

All data from CEMS is recorded on electronic historian system along 

with plant production rates

CEMS Manufacturer Ametek

CEMS Model Number 400/461 serial # 4612

Description of sample extraction and 

conditioning or dew point 

maintenance systems

A 1⁄4” sample probe is used on the stack. The probe is connected to a 1⁄4” 

electrically traced tubing from the stack to the analyzer heated to 220 F.

Ability to distinguish between NO 

and NO2?

The analyzer samples every 10 minutes. After 170 seconds the NO2 

concentration can be seen. Five seconds after, oxygen is injected to 

convert all NO to NO2. This sample converts for 7.5 minutes which 

gives us our total NOx ppm reading at the end of the sample period. The 

subtraction of the final reading from the reading after 170 seconds from 

the start gives the NO concentration in the stack. Only the total NOx 

concentration is electronically recorded for the CEMS data.

Identify all periods of startup, 

shutdown, and malfunction, 

regardless of whether the event 

caused an exceedence (during the 

past 3 years) See table at end of document

Capital costs Estimate $50,000 to $100,000.

Operation and Maintenance costs Calibration gas=$3,000/yr, Parts and Maintenance=$5,000/yr

Cost of quarterly audits RATA cost= $8,000/yr CGA=$1,000

Year began operation 1994

Continuous Emission Monitoring Systems

TRAIN III- SECOND ANALYZER TO MEASURE N2O with ability to measure NO and NO2

(Note-not used for CEMS reporting data due to analyzer not being certified)

? Plant CEMS data recorded 

concurrent with test runs (i.e., 

concentration, etc.).

All data from CEMS is recorded on electronic historian system along 

with plant production rates

CEMS Manufacturer Ecochem

CEMS Model Number MC3 s-serial SN282

Description of sample extraction and 

conditioning or dew point 

maintenance systems

A 1⁄4” sample probe is used on the stack. The probe is connected to a 1⁄4” 

electrically traced tubing from the stack to the analyzer heated to 365 F.

Ability to distinguish between NO 

and NO2?

NO, NO2 and N2O are measured separately by the analyzer. NO and 

NO2 are added together in the analyzer and the sum total is sent to the 

DCS and historian as a NOx reading
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Identify all periods of startup, 

shutdown, and malfunction, 

regardless of whether the event 

caused an exceedence (during the 

past 3 years) N/A (see CEMS description)

Capital costs $92,000.

Operation and Maintenance costs Calibration gas=$4,000./yr, Parts and Maintenance=$5,000./yr

Cost of quarterly audits RATA cost= $8,000/yr CGA=$1,000

Year began operation 2008

Continuous Emission Monitoring Systems

CEMS Information-Train IV

? Plant CEMS data recorded 

concurrent with test runs (i.e., 

concentration, etc.).

All data from CEMS is recorded on electronic historian system along 

with plant production rates

CEMS Manufacturer Ametek

CEMS Model Number 400/461 serial # 7969

Description of sample extraction and 

conditioning or dew point 

maintenance systems

A 1⁄4” sample probe is used on the stack. The probe is connected to a 1⁄4” 

electrically traced tubing from the stack to the analyzer heated to 220 F.

Ability to distinguish between NO 

and NO2?

The analyzer samples every 10 minutes. After 170 seconds the NO2 

concentration can be seen. Five seconds after, oxygen is injected to 

convert all NO to NO2. This sample converts for 7.5 minutes which 

gives us our total NOx ppm reading at the end of the sample period. The 

subtraction of the final reading from the reading after 170 seconds from 

the start gives the NO concentration in the stack. Only the total NOx 

concentration is electronically recorded for the CEMS data.

Identify all periods of startup, 

shutdown, and malfunction, 

regardless of whether the event 

caused an exceedence (during the 

past 3 years) See table at end of document

Capital costs Estimate $50,000 to $100,000.

Operation and Maintenance costs Calibration gas=$3,000/yr, Parts and Maintenance=$5,000/yr

Cost of quarterly audits RATA cost= $8,000/yr CGA=$1,000

Year began operation 1997
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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Continuous Emission Monitoring Systems

CEMS Information-Train V

? Plant CEMS data recorded 

concurrent with test runs (i.e., 

concentration, etc.). All data from CEMS is recorded on electronic historian system

CEMS Manufacturer Ametek

CEMS Model Number 920 NOx serial AZ-920GPSP-89982

Description of sample extraction and 

conditioning or dew point 

maintenance systems

A 1⁄4” sample probe is used on the stack. The probe is connected to a 1⁄4” 

electrically traced tubing from the stack to the analyzer heated to 220 F.

Ability to distinguish between NO 

and NO2?

NO2 and NO readings are measured separately by the analyzer. Both 

readings are sent to the DCS. The total of both readings are added 

together for a total NOx concentration and stored in the historian for 

CEMS data.

Identify all periods of startup, 

shutdown, and malfunction, 

regardless of whether the event 

caused an exceedence (during the 

past 3 years) See table at end of document

Capital costs $55,000 in 2000

Operation and Maintenance costs Calibration gas=$2,400/yr, Parts and Maintenance=$5,000/yr

Cost of quarterly audits RATA cost= $8,000/yr CGA=$1,000

Year began operation 2000

Continuous Emission Monitoring Systems

TRAIN V-SECOND ANALYZER TO MEASURE N2O with ability to measure NO and NO2

(Note-not used for CEMS reporting data due to analyzer not being certified)

? Plant CEMS data recorded 

concurrent with test runs (i.e., 

concentration, etc.).

All data from CEMS is recorded on electronic historian system along 

with plant production rates

CEMS Manufacturer Ecochem

CEMS Model Number MC3 s-serial SN282

Description of sample extraction and 

conditioning or dew point 

maintenance systems

A 1⁄4” sample probe is used on the stack. The probe is connected to a 1⁄4” 

electrically traced tubing from the stack to the analyzer heated to 365 F.
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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Ability to distinguish between NO 

and NO2?

NO, NO2 and N2O are measured separately by the analyzer. NO and 

NO2 are added together in the analyzer and the sum total is sent to the 

DCS and historian as a NOx reading.

Identify all periods of startup, 

shutdown, and malfunction, 

regardless of whether the event 

caused an exceedence (during the 

past 3 years) N/A (see CEMS description)

Capital costs $101,000.

Operation and Maintenance costs Calibration gas=$4,000./yr, Parts and Maintenance=$5,000./yr

Cost of quarterly audits RATA cost= $8,000/yr CGA=$1,000

Year began operation 2008

CEMS Data (Monthly and Annual)

Include monthly and annual NOX CEMS data for the last 3 years. Please submit the CEMS 

data electronically.
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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General Discussion

1. Please provide your thoughts on trends in nitric acid production as far as type of process that 

is used; types of absorber used, trends in selecting control devices, improvements in control 

efficiency in existing control devices, energy efficiency.

Most nitric acid plants are designed to produce acid at a maximum strength of 65-67 %. The 

azetrope (constant – boiling mixture) of nitric is 68 % which sets the maximum concentration 

that can be achieved with conventional absorption towers. Acid strengths are typically limited 

to 65 % to give flexibility and allow for lower NOx slip out of the absorber. Acid strengths 

above 68 % involve plant designs that are significantly more complicated, have much higher

capital and much higher operational cost and suffer from many corrosion challenges. Due to 

the complexity and cost of producing nitric acid above 68%, most down stream processes that 

require nitric acid have been designed to operate with an acid strength of 65% or less.

Train V Nitric Acid was commissioned in 1999 and was state of the art technology when 

installed and to this date still is. It is a dual pressure, Grand Paroisse design with a SCR for 

NOx abatement and control. With the dual-pressure process, the oxidation of ammonia takes 

place at a medium pressure of 60 to 90 psia as this has advantages for the efficiency of the 

ammonia combustion and the consumption of the precious metal catalyst. The absorption step 

is operated at the higher pressure of 130-200 psia which enhances the efficiency of the 

absorption. The capital cost of a dual pressure plant is higher since it has an addional NOx 

compressor and additional process equipment. However, with a large plant, typically greater 

than 1000 TPD, the additional capital cost can be justified by the future savings in efficiency

over that of a mono-pressure plant.

When designing an absorption column, the goal is to reduce the NOx slip out the absorber as 

much as possible since any NOx slip from the absorber results in less acid production and 

more reagent required in the NOx abatement technology (ie; ammonia to SCR or methane to 

NSCR) The efficiency of the absorption column is determined by the following:

1) Size of tower and number of absorption trays

2) The amount of cooling in the tower is very important in plant efficiency as the lower the 

temperature the more efficient the absorption. Tower cooling removes the heat of reaction

from NO2 absorbing into the water forming nitric acid and from the exothermic reaction of NO 

converting to NO2. 

3) The oxidation state of the NOx gas entering the tower is important for plant efficiency. NO 

is produced by the oxidation reaction of ammonia and oxygen on the platinum gauze. After 

the gauze, the NO reacts with excess oxygen to form NO2. This is a slow reaction that requires 

residence time and favors lower temperatures. The more NO that has reacted to NO2 prior to 

introduction into the absorption column, the more efficient the tower will be. If there is not 

enough residence time or excess oxygen available to allow for NO to react to NO2 then the 

exothermic reaction will occur in the tower and reduce the tower efficiency. Oxidation 

chambers or long runs of piping are typically designed into plant to allow for this reaction prior 
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to the absorption column.

4) The higher the pressure of the absorption column the higher the efficiency as the absorption

efficiency relationship to pressure is tertiary (tower efficiency ~ pressure 3).

NOx Abatement

For NOx abatement SCR is typically the most viable technology on a new plant or on most 

plant upgrades. SCRs can control down to very low NOx levels and have a wide temperature 

operability range which allows for easy integration into many process designs.

NSCR operate at high temperatures; typically above 1000 deg. F. Acid plants designed with a 

NSCR typically have the “back end” designed around the NSCR system to take advantage of 

the heat generated from the reaction of methane or other fuel in the catalyst bed. The hot gas 

exiting the NSCR is typically fed directly into the hot gas expander and is responsible for a 

large portion of the power used to drive the air compressor. The reagent costs are high on a 

NSCR but most of the energy is recovered in the hot gas expander. With high efficiency 

expanders, the NSCR plant can be just as efficient as a plant with SCR catalyst and the plants

are typically large exporters of steam. 

Other Improvements in Modern Plants

There are many other improvements that have made modern plants more efficient. Some of 

these are:

-Improved efficiency of large rotating equipment such air compressors, steam turbine and hot 

gas expanders.

-Better energy integration, recovery of low level heat and loss of less heat into the cooling 

water system.

-Forced circulation boiler downstream of the oxidation catalyst. These boilers efficiently

recover the heat from burning the ammonia and have proven to be very reliable.
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2. Please describe your thoughts on the air pollution controls that are used at your facility such 

as reliability, O&M costs including energy penalty, etc.

Reliability and Operability

The four technologies that are used to control NOx at PCS Geismar are well developed 

technologies that are very reliable. SCR with automatic control of ammonia injection tied into 

a continually updating analyzer allows for very precise control and ease of operation. 

Extended absorption is quite simple and thus reliable but is dependent on the reliability of a

refrigeration compressor. Installation of a rotary screw refrigeration compressor has proven to 

be very reliable. The NSCR runs very reliably and allows for Train IV to be a large exporter of 

steam which is used through out the complex.

Efficiency

SCRs are efficient as long as the inlet concentration of NOx is reasonable. High concentrations

of inlet NOx result in high ammonia consumption and slight reduction in acid production 

which is a cost to the plant with no economic return.

NSCRs can be efficient as long as the hot exit gas is recovered in an efficient hot gas expander. 

With the proper configuration of a NSCR in conjunction with an efficient expander; 

efficiencies will be comparable to co-gen style gas turbines. Typically, addional heat recovery 

is done down stream of the expander in the form of steam generation or boiler feed water preheat in order to ensure maximum efficiency of the plant.

Extended absorption is very efficient because it allows for all the NOx with the exception of 

what is released to the stack to be recovered in the product acid. Ultra low emissions are 

difficult to achieve with extended absorption. 

3. Please provide recommendations on the revisions you would like to see in this NSPS.

1. Maintain the current standard of 3 lb/ton

2. Provide an online adjustment period for plant malfunctions unless the adjustment period 

emissions exceed start-up/shut-down emissions

3. If lower NOx emissions are required, reduce the long term emission rate (or provide a 12-

month rolling total mass cap) but allow the current standard as a short term emission rate to 

provide greater operational flexibility.

4. Clarify the monitoring and reporting requirements in Subpart A and Subpart G. Set up a 

matrix identifying which sections of Subpart A are applicable to Subpart G affected sources so 
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that the regulated community does not have to go from Subpart to Subpart, section to section in 

an attempt to identify all requirements. 

5. Make the regulations generally more understandable and usable.

Startup, Shutdown, and Malfunction

1. Please describe the maximum emission levels of NOX or NH3 expected during a startup, 

shutdown, and malfunction event. 

The three acid trains at PCS Geismar respond differently during start up and their ability to 

reduce NOx emissions

Train III

Train III has two NOx abatement technologies: 1) extended absorption and 2) SCR down 

stream of the expander. During start up, the plant can be operated so that the NOx 

concentration exiting the absorber can be controlled low enough as to not overwhelm the SCR 

which allows the SCR to maintain and control NOx emissions below 3 lbs/ton during start up. 

In addition, a feature that allows for tight NOx control is a continually updating NOx analyzer. 

This allows for precise automatic control of NOx emissions and helps prevent the overfeeding 

of ammonia to the SCR. This continually updating analyzer was installed in 2009 and is part 

of the analyzer used to measure N2O emissions. During a typical start up the NOx emission 

average between 2.0 to 3.0 lbs/ton for the first hour. Then, after the first hour of operation NOx 

can then be controlled at the average emission range. Shut down emissions are typically 

controlled within the average range and malfunction or plant upset can typically be 

compensated within the SCR in 15 minutes.

Train IV

Train IV uses NSCR abatement technology to reduce NOx. Natural gas can only be 

introduced to the NSCR after ammonia feed has started to the oxidation catalyst (platinum 

gauze). Process control safety interlocks are designed in order prevent an explosive condition

of natural gas and air within the process piping. For this reason, these controls do not permit 

natural gas addition to the NSCR until commencement of ammonia flow to the oxidation 

catalyst. 

In a single pressure plant with a NSCR, two sources of energy drive the air compressor that 

supplies air to the oxidation catalyst 1) Steam Turbine and 2) Hot Gas Expander downstream 

of the NSCR. Prior to the introduction of ammonia to the oxidation catalyst, the only source of 
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energy to drive the air compressor is the steam turbine which only is able to achieve a 

moderate plant pressure resulting in reduced absorber efficiency. Once the ammonia feed is 

started to the oxidation catalyst, then natural gas flow can be started to the NSCR. The heat 

generated from burning the natural gas in the NSCR then drives the expander and quickly 

brings the compressor speed up. With the increasing speed of the air compressor the pressure 

of the absorption column increases which improves efficiency and drops the NOx slip out of 

the tower. However, for that short period of time before the expander drives the compressor,

the absorber efficiency is low which results in excess NOx slip from the absorber. Once the 

plant is lined out and the oxidation reaction is up to temperature, then the NSCR is optimized 

and the NOx emissions come into range. In the first 60 minutes after start up, NOx emissions

typically run between 5.5 and the maximum permit limit of 6.5 lbs/ton. Occasionally the 

maximum permit limit is exceeded but not typically. After the first hour of operation, NOx 

emissions drop to the normal average operating range. Shut down emission rates run higher 

than average, between 3.0 and 6.5 lbs/ton for approximately one hour. Plant malfunction and 

swings such as change in ammonia pressure or swing in oxidation catalyst temperature can 

result in higher emission rates in the 3.0-5.0 lbs/ton range.

Train V

Train V NOx is easily controlled within the maximum limit of 3 lbs/ton during start up / shut 

down and most malfunctions. The maximum limit is much higher than the normal operating 

range of 0.3-0.4 lbs/ ton which helps to prevent NOx slip over the maximum permit limit.

Many features of the plant allow for NOx to be controlled within permit limits during start up

and shut down. Some of these design features include:

- Dual pressure design with guide vane control on the air compressor and expander

which allows for greater control of the tower pressure during various modes of 

operation

- Start up heater upstream of the SCR that allows for the SCR catalyst bed temperatures

to be optimized before high levels of NOx reduction is required.

- SCR that can be put into service prior to introduction of ammonia to the oxidation 

catalyst

- Efficient absorption column (greater than 200’ tall) which help reduce NOx slip. The 

lower NOx concentration from the column then results in a reduced load on the SCR 

reactor.

- Continually updating NOx analyzer which allows for precise control of NOx and 

prevent overfeeding of ammonia to the SCR

Start up emissions in Train V can be anywhere from 0.5– 3.0 lbs/ton but rarely exceed the 

maximum limit of 3 lbs/ton. Normal average emission rates are typically achieved one to two

hours after start up. Malfunction or plant upset typically don’t have a significant effect on 

NOx and rarely cause emissions to go over 1.0 lbs/ton. Controlled shut downs have NOx 

emissions within the average range. Trip outs result in emissions between 1.0 and 3.0 lbs/ton.
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2. Please describe how long excess/elevated emissions NOX or NH3 will typically occur during 

a startup, shutdown, and malfunction event. 

Train III

With two emission control technologies in Train III, (extended absorption and SCR) the 

emissions are able to be controlled below the 3 lbs/ ton limit during nearly all startup, 

shutdown or typical plant malfunctions. For example if the SCR unit was to fail on loss of 

ammonia feed, adjustments can be made to the plant such as increased demineralized water 

flow to the top of the absorber which would prevent the plant from exceeding the emission 

limit. In Train III, the normal (average) NOx emission limits are typically achieved within 30 

minutes after the ammonia is introduced to the oxidation catalyst (gauze). During shut down 

elevated emissions rarely exceed one hour.

Train IV

During start up, Train IV typically operates with high emission for one hour after ammonia 

flow has started to the oxidation catalyst. Typically the NOx can be controlled down into the 

normal operating range within one hour of start up. Most plant upset or small malfunctions

can be quickly compensated for and NOx emissions can be returned back to normal within 15 

minutes. On shut down, elevated emission typically last NOx for 30 to 60 minutes.

Train V

Elevated start up emissions can last from one to two hours. Most plant upsets or small 

malfunction can be compensated within minutes and typically do not raise emissions above the 

average. If the shut down result in elevated emission, which is not typical, these typically last 

for less than on hour. 

3. Please describe any equipment or work practices that are employed to minimize or 

eliminate the quantity or duration of excess/elevated emissions of NOX or NH3 during 

startup, shutdown, and malfunction events. 

The following steps are taken in the each of the Geismar plants to lower emissions on start up 

prior to commencing ammonia flow to the oxidation catalyst:

1) The pressure of the absorption tower is maximized. This is achieved by operating the 

steam turbine that drives the air compressor at 100%.

2) The trays in the absorption column are filled with demineralized water. This is 

determined by a pressure drop across the absorption tower along with a rising liquid 
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level in the bottom of the absorption column. 

3) Demineralized water is maximized to the top of the absorption column and weak acid 

flow is maximized to the lower trays of the tower.

4) Cooling water is maximized to the tower to optimize absorption efficiency and in Train 

3, the refrigeration compressor is put into service and the extended absorption section 

of the tower is chilled down to 40F.

5) The SCRs are commissioned and put in service to be ready to immediately reduce NOx 

emissions. 

6) In Train V, the start up steam heater upstream of the SCR is put into service to bring 

the SCR up to efficient operating temperature to ensure optimum conversion of NOx to 

nitrogen and reduce ammonia slip. 

Immediately after ammonia flow is started to the oxidation catalyst (gauze is lit), the following 

step are made to reduce NOx emissions.

1) The NSCR is put into service in Train IV.

2) The air compressor is sped up with the additional energy from the hot gas expander that 

comes from the heat that is generated from the oxidation reaction.

3) The oxidation catalyst is brought up to normal operating temperature and lined out very 

quickly. 

4) The absorber pressure is raised to normal operating pressure in each of the plants.

TRAIN III

Duration of 

DATE time Status Event 

(hours)

1/15/2007 19:30 startup 1:00

1/31/2007 shutdown 1:00

2/27/2007 21:45 startup 0:45

3/6/2007 0:30 shutdown 1:45

3/9/2007 15:15 startup 2:00

3/30/2007 6:00 shutdown 1:30

3/31/2007 22:45 startup 0:30

4/8/2007 2:45 shutdown 0:45

4/12/2007 3:45 startup 1:00

5/20/2007 15:00 shutdown 0:30

5/31/2007 0:30 startup 1:00
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7/8/2007 18:00 shutdown 1:45

7/29/2007 14:15 startup 1:45

8/2/2007 3:30 shutdown 2:00

8/2/2007 23:45 startup 1:45

8/7/2008 9:00 shutdown 2:30

8/23/2007 9:00 shutdown 0:30

8/23/2007 21:30 startup 1:45

8/28/2007 18:45 shutdown 1:45

8/29/2007 0:00 startup 0:45

9/13/2007 11:00 shutdown 3:30

9/14/2007 18:15 startup 1:30

10/26/2007 5:00 shutdown 0:15

10/27/2007 6:30 startup 1:30

10/31/2007 14:15 shutdown 0:15

10/31/2007 14:45 startup 1:00

11/7/2007 20:15 shutdown 3:00

11/8/2007 14:20 startup

11/18/2007 6:10 shutdown 1:50

11/29/2007 6:45 startup 1:00

12/7/2007 5:30 shutdown 0:15

12/20/2007 startup 0:00

12/31/2007 shutdown 0:00

1/6/2008 18:30 startup 1:15

1/31/2008 9:30 malfunction 3:30

2/5/2008 1:00 shutdown 2:30

2/6/2008 21:00 startup 1:30

3/7/2008 13:30 shutdown 1:00

3/15/2008 startup 0:00

4/5/2008 15:15 shutdown 2:15

4/6/2008 14:00 startup 3:00

4/8/2008 4:15 shutdown

4/8/2008 15:15 startup 1:30

4/11/2008 6:15 shutdown 1:00

4/12/2008 19:30 startup 2:30

4/25/2008 0:00 shutdown 0:15

5/3/2008 14:00 startup 3:45

5/12/2008 shutdown

5/27/2008 18:40 startup 3:05

5/30/2008 9:20 shutdown 1:25

6/2/2008 2:00 startup 0:30

6/8/2008 19:15 shutdown 1:00

6/9/2008 9:15 startup 3:00

6/19/2008 shutdown

7/2/2008 14:45 startup 2:30

7/21/2008 11:00 shutdown 1:00

7/23/2008 1:30 startup

8/13/2008 18:45 shutdown 2:15

8/14/2008 11:30 startup 1:15

8/15/2008 10:00 shutdown 0:15
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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8/16/2008 0:00 startup 0:15

8/20/2008 3:30 shutdown 0:15

8/30/2008 13:30 startup 0:15

10/9/2008 15:45 shutdown 1:30

10/21/2008 12:00 startup 0:15

10/30/2008 2:45 shutdown 1:45

10/31/2008 22:15 startup 2:45

11/13/2008 21:00 startup 0:30

11/18/2008 22:15 shutdown 1:00

12/18/2008 19:45 startup 2:00

12/29/2008 10:45 shutdown 0:45

12/30/2008 21:45 startup 0:15

1/6/2009 6:15 shutdown 0:15

9/4/2009 14:30 startup 2:45

9/16/2009 10:00 shutdown 1:46

9/29/2009 22:30 startup 1:00

10/7/2009 21:15 shutdown 0:15

10/27/2009 17:30 startup 0:15

11/3/2009 21:00 shutdown 0:15

11/19/2009 11:15 startup 0:15

11/28/2009 8:45 shutdown 0:30

TRAIN 

IV Duration 

Date Time Status of event

(hours)

2/7/2007 19:00 shut down 1:30

2/21/2007 7:35 startup 6:10

3/1/2007 7:45 shutdown 2:15

3/2/2007 7:20 4:30 7:40

3/30/2007 0:15 shutdown 1:15

3/30/2007 22:00 startup 1:45

4/1/2007 15:00 malfunction 0:45

4/11/2007 17:15 malfunction 1:30

4/23/2007 13:30 shutdown

4/29/2007 10:00 startup 0:00

4/29/2007 15:00 malfunction 0:00

5/18/2007 20:00 shutdown 2:15

5/23/2007 15:00 startup 2:15

7/5/2007 2:00 shutdown 1:45

7/6/2007 5:00 startup 2:30

8/7/2007 0:00 shutdown 0:45

8/8/2008 1:00 startup 0:30

8/15/2007 14:00 malfunction

8/28/2008 18:45 shutdown 1:00

8/29/2007 1:01 startup 1:14

9/25/2007 17:45 shutdown 1:30

9/26/2007 22:30 startup 4:00
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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11/2/2007 8:30 shutdown 0:15

11/4/2007 7:00 startup 1:30

11/15/2007 19:30 shutdown 1:00

12/6/2007 19:15 startup 1:45

1/28/2008 0:10 shutdown 1:50

2/8/2008 12:10 startup 1:05

3/13/2008 0:00 shutdown 2:45

3/16/2008 22:00 startup 1:30

3/27/2008 10:00 shutdown 1:30

3/27/2008 23:30 startup 1:15

4/18/2008 11:45 shutdown 1:15

4/18/2008 20:25 startup 1:50

5/11/2008 20:00 shutdown 1:00

5/23/2008 22:45 startup 4:00

7/29/2008 0:00 shutdown 0:45

7/229/2008 19:00 startup 0:30

8/13/2008 6:15 shutdown 4:00

8/13/2008 12:00 startup 0:15

8/15/2008 19:00 malfunction 1:00

8/23/2008 3:30 malfunction 12:00

8/31/2008 5:00 shutdown 0:00

9/18/2008 startup

10/17/2008 shutdown

10/26/2008 startup

10/27/2008 0:15 malfunction 18:00

10/30/2008 2:45 shutdown 0:00

10/31/2008 17:50 startup 0:00

12/2/2008 5:00 shutdown 0:00

12/12/2008 19:30 startup 1:45

12/15/2008 13:00 malfunction 0:00

12/18/2008 8:00 malfunction 0:00

1/6/2009 6:00 shutdown 1:30

6/10/2009 12:00 startup 4:00

6/16/2009 10:00 shutdown 2:00

7/29/2009 11:00 startup 3:00

7/30/2009 0:00 malfunction 2:00

8/4/2009 2:00 shutdown 1:00

8/5/2009 0:00 startup 1:00

8/18/2009 9:00 malfunction 0:00

9/22/2009 17:00 malfunction 0:00

9/23/2009 0:00 malfunction 2:00

9/28/2009 6:00 shutdown 1:00

10/24/2009 startup

10/27/2009 shutdown

10/27/2009 startup

11/28/2009 11:00 shutdown 2:00

TRAIN V Duration of 

Date time Status Event 
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(hours)

3/8/2007 21:30 startup 1:15

4/14/2007 1:15 shutdown 1:30

4/14/2007 10:30 startup 1:30

4/20/2007 5:00 shutdown 4:00

4/20/2007 14:15 startup 1:45

5/14/2007 11:45 shutdown 2:15

8/11/2007 21:30 startup 1:30

8/29/2007 3:00 shutdown 0:30

8/29/2008 6:15 startup 0:15

9/11/2007 10:45 shutdown 2:45

9/13/2007 11:30 startup 2:15

10/30/2007 3:00 shutdown 0:30

10/31/2007 9:00 startup 2:00

1/3/2008 10:15 shutdown 0:15

1/4/2008 1:30 startup 1:15

3/3/2008 15:15 shutdown 0:15

3/6/2008 0:00 startup 1:30

3/16/2008 18:00 shutdown 0:30

3/20/2008 13:00 u startup 4:45

3/19/2008 12:00 shutdown 1:00

5/24/2008 3:00 startup 2:00

5/29/2008 16:00 shutdown 3:30

6/13/2008 7:15 startup 1:00

7/23/2008 14:00 shutdown 0:15

7/23/2008 17:15 startup 1:45

8/13/2008 6:00 shutdown 1:00

8/13/2008 16:00 startup 1:15

8/16/2008 5:00 shutdown 0:30

8/16/2008 11:45 startup 0:45

8/26/2008 3:15 shutdown 0:30

8/30/2008 9:30 startup 2:30

8/31/2008 shutdown 0:00

9/8/2008 6:00 startup 3:15

9/23/2008 20:00 repair SCR 0:30

10/30/2009 1:25 shutdown 9:35

10/30/2008 14:00 startup 4:45

10/31/2009 4:45 shutdown 0:15

11/2/2008 4:00 startup 0:45

11/13/2008 15:45 shutdown 0:15

12/1/2008 21:30 startup 1:00

12/11/2009 7:45 shutdown 1:45

1/5/2009 13:45 startup 4:15

1/29/2009 22:00 shutdown 3:00

1/30/2009 5:00 startup 4:45

3/3/2009 11:30 startup 0:30

3/29/2009 20:00 shutdown 2:45

4/7/2009 10:45 startup 1:15
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5/11/2009 20:00 shutdown 0:30

5/18/2009 15:45 startup 4:00

6/1/2009 5:00 shutdown 0:45

6/8/2009 10:45 startup 0:15

6/29/2009 11:30 shutdown 0:30

7/2/2009 11:15 startup 1:00

8/15/2009 4:00 shutdown 1:15

8/16/2009 11:30 startup 0:30

9/21/2021 21:30 shutdown 1:00

9/23/2009 8:45 startup 0:30

10/21/2009 16:30 shutdown 0:15

10/22/2009 22:30 startup 0:15

11/9/2009 19:45 shutdown 0:15

11/17/2009 6:30 startup 1:00

11/17/2009 21:15 shutdown 0:30

11/26/2009 13:45 startup 0:15

12/13/2009 15:00 shutdown 1:00

12/15/2009 17:00 startup 1:00

12/22/2009 8:00 shutdown 1:00

12/29/2009 22:00 startup 1:59

12/30/2009 0:00 shutdown 1:00
EPA Information Collection Request for Nitric Acid NSPS (Subpart G)—Electronic Version

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Emission Testing

1. Include emissions testing conducted during the last five years. Include tests for NOX, and 

NH3. Read and follow the guidance below.

2. Test method data of interest include those performed according to EPA Methods 7, 7A, 7B, 

7C, 7D, or Method 320.

3. Method 7E (for NOX) data can be submitted, but only if the testing was performed with the 

following modifications for nitric acid plants. Because of the propensity of NO2 to be 

absorbed by water, the sampled gas must not contact any condensate, and the efficiency of 

any NO2 to NO converter (if needed by the detection principle of the instrument) must be 

determined and documented as described in the method. For wet basis measurement systems, 

the tester must measure and report temperature data to show that the sample line and all 

sample transport components up to the inlet of the analyzer (and, for hot-wet extractive 

systems, also the analyzer) were maintained above the stack gas dew point. Use of a dilution 

probe to reduce the dew point is an acceptable procedure, if documented. Section 8 of 

Method 7E describes the measurement system performance tests and documentation required 

by the method, both prior to and following sampling. NO2 calibration gas must be substituted 

for NO calibration gas in the performance of system bias checks. The alternative mentioned 

in Section 8.6 to follow the dynamic spike procedure in Section 16.1 is acceptable, but only 

with NO2 spike gas. The dynamic spiking procedure is strongly recommended.

4. If you do not have emission test data for NOX using a method in note 2 or using Method 7E 

according to the modified protocol in note 3, you must conduct a stack test to determine 

NOX emissions following one of the approved methods above.

5. If you do not have emission test data for NH3, you must conduct a stack test to determine 

the emissions using the procedures of Method 320.

6. If a concentration is at or below the applicable method’s detection level, then provide 

information about the method (title and source), the calculated detection level in units of the 

applicable raw material or emissions concentration or mass rate, and the procedure for 

determining the detection level.

7. Additional stack testing guidance is contained in Enclosure 7.