Date: May 2012 Subject: Analy ses of Data Received Between Proposal and Promulgation of Part 60,

Subpart Ga Nitric Acid NSPS Review EPA Contract No. EP
- D
- 11
- 084; Work Assignment No. 0

- 0 1 RTIProject No. 02103199.000.001 From: Melissa Icenhour To: Nathan Topham

OAQPS/SPPD/M IC G (D243

- 02) U. S. Environmental Protection Agency Research Triangle Park, NC 27711
Introduction In submitting comments on the proposed rule , NSPS Review of Nitric Acid (Subpart Ga), American Chemistry

Council (ACC) mentioned that a separate NO X emission standard should be developed for small single pressure units. No additional continuous emissions monitoring sy stem (CEMS) data were received during the public comment period . T he EPA held a teleconference with representatives of ACC on January 11, 2012. A s a result of the meeting, ACC volunteered to provide ( CEMS ) nitric oxides (NO X) data for multiple monopressure nitric acid plants b y the end of the day

on January

16, 2012 See Teleconference with American Chemi stry Council on January 11, 2012
. Submissions were received from Dow, DuPont, and L SB Industries (owners of El Dorado Nitrogen). As shown in Table 1 , the NO X emissions were generally higher than the final emission limit . The average emissions for some faci lities could not be determined because hourl y data was not supplied. In the case of Dow Sterlington, concentration data were supplied as 3 hour averages. Therefore the 30 operating day emission rate could not be calculated. All data and anal ys es are contai ned in Docket EPA

- HQ
- OAR
- 2010
- 0750. The following paragraphs summarize the data received from Dow, DuPont, and L SB Industries

.Dow
- Sterlington

.

Dow submitted data for 1 nitric acid plant in Sterlington, Louisiana. As discussed previously , Dow did not sub mit hourly averages so the anal ys is was limited. There were 5,812 data points ranging from 0.0 lb NO X/ton acid to 12.37 lb NO X/ton acid . The median was 0.42 lb NO X/ton acid and the average was 0.72 lb NO X/ton acid. The Sterlington nitric acid plant is a si ngle pressure design, employing extended absorption and NSCR as NO X abatement. The plant produces 200 tons per day of 100% nitric acid. However, this plant could improve the performance of their NSCR by replacing the catal ys t more often. According to the f acility , the design life of the catal ys t is 15 years but the actual life has been 25 ye ars. If modifications are made to this plant such that the plant bec omes subject to Subpart Ga , the plant could improve emissions reductions by replacing the catal ys t m ore often. DuPont
- Pascagoula

. DuPont submitted data for 1 nitric acid plant in Pascagoula, Mississippi, and 1 nitric acid plant in Beaumont, Texas. The Pascagoula plant began operation in 1992. It has a single pressure design with no extended absorption and uses SCR as NO X abatement. The plant produces 230 tons per day of 62% nitric acid. This plant could also improve the performance of the abatement device by replacing the catal ys t more often. According to the facility, the design life of the catal ys t is 9 ye ars but the actual life has been 13 years. The supplied hourly averages show that the facility emits approximately

1.3 lb NO X per ton acid except for one hour each day where the hourly average is approximately 6.0 lb NO X per ton acid. If modifications are made to this plant such that the plant bec o me s subject to Subpart Ga, this plant could improve emissions reductions by employing extended absorption and by improving the effectiveness of the SCR by replacing the catal ys t more often. See Figure 1 for a plot of the 30 operating day rolling emission rates for the Pascagoula plant during 2011. Emission rates range from 0.5 6 to 1.6 3 lb NO X/ton acid but 82% of the data were greater than 1.0 lb NO X/ton acid

.DuPont
- Beaumont.

The Beaumont plant began operati on in 1971. It has a single pressure design with no extended absorption and uses NSCR as NO X abatement. The plant produces 250 tons per day of 63% nitric acid. Hourl y data were not supplied so the 30 operating day rolling emission rates could not be calcul ated. The plant supplied 24 hour average s which range from 0.00 to 1.97 lb NO X/ton acid and averages 0.79 lb NO X/ton acid. If modifications are made to this plant such that the plant bec o me s subject to Subpart Ga , the plant could improve emissions reductio ns by employing extended absorption or installing an SCR
. LSB Industries

- East and West. The East and West units began operation in 1962 and are not subject to subpart G and are controlled by

an SCR. The East unit produces 300 tons of 52%
- 58% nitric acid p er day and the West unit produces 288 tons of 52%
- 58% nitric acid per day . According to the facility , the design life of the SCR cataly st is 11 to 15 years. The data submitted by the company

covered the period of January

2011 through December 2011. The cat al ys t was replaced in August 2011, which means that the data from January through July

2011 is likely

to be higher than typical because the cataly st was near the end of its useful life. Also, the SCR unit is located after the gas expander. According to Jeremy Richard of PSC Geismar (see document 0062 in docket EPA

- HQ
- OAR
- 2010
- 0750), the mixing of gas and ammonia within the SCR is not ideal at this location. For best practice, the SCR should be located before the gas expander. Therefore, the East/West units are poorl y performing plants and are not consistent with best sy stem of emissions reductions. If modifications are made to th ese plant s such that the plants bec o me subject to Subpart Ga , the plants could improve emissions reductions by changing the locatio n of the SCR, and replacing the catal ys t more often. See Figure 2 for a plot of the 30 operating day rolling emission rates for the East nitric acid plant during 2011. Emission rates range from 4.4 to 13.0 lb NO X/ton acid and average 8.22 lb NO X/ton acid. See Figure 3 for a plot of the 30 operating day rolling emission rates for the West nitric acid plant during 2011. Emission rates range from 2.4 to 1 1.9 lb NO X/ton acid and average 6.1 lb NO X/ton acid.LSB Industries

- Cherokee No. 2 and DMW.

These nitric acid units have single pressure designs and only use extended absorption for NO X abatement. Hourl y data were not supplied for the Cherokee No. 2 plant so the 30 operating day rolling emission rates could not be calculated. The plant supplied 24 hour averag e s which range from 0.0 4 to 3.83 lb NO X/ton acid and average 2.57 lb NO X/ton acid. If modifications are made to th ese plant s such that the plants bec o me subject to Subpart Ga , the plants could significantly reduce emissions reductions by installing an SCR or an NSCR. See Figure 4 for a plot of the 30 operating day rolling emission rates for the DMW plant during 2011

. Emission rates range from 3.0 to 5.1 lb NO X/ton acid and average 3.88 lb NO X/ton acid.

Conclusions. T he additional data received included ni tric acid plants that are not currently subject to subpart G, are not currently controlled, or are generall y not employing the best system of emissions reductions (BSER). These facilities may need to install additional controls to comply with subpart Ga if they

are modified or reconstructed and trigger the standard. See Impacts of Nitric Acid NSPS Review

-NO X (Updated memo for Final NSPS) . However, these facilities do not illustrate that an emission standard of 0.50 lb NO X/ton acid is not achievable and thus would not have impacted the level of the standard in the final rule.

### Table 1. Facility Data Received in January 2012

**Plant Location**  **Unit Year nitric acid**  **plant constructed**  **Year of**

**Data Type**  **Control device**  **30 operating day rolling**

**emission rate Highest**  **Emission Rate (lb NO**  **X /ton acid)**  Dow Sterlington

----- 1976 2011 Monopressure NSCR
----- a DuPont Beaumont
----- 1971 2009
- 2010 Monopressure NSCR
----- b DuPont Pascagoula

----- 1992 2011 Monopressure SCR 1.63 LSB Industries East 1962 2011 Mono pressure SCR 13.02 LSB Industries West 1962 2011 Monopressure SCR 11.87 LSB Industries Cherokee Unknown 2011 Monopressure None
----- b LSB Industries DMW Unknown 2011 Monopressure None 5.11 a Only 3 hour averages were supplied. b Hourly data were not supplied.

### Figure 1. **DuPont Pascagoula Nitric Acid Plant in 2011** 

### Figure **2 .**  **LSB Industries East Nitric Acid Plant in 2011** 

### Figure **3 .**  **LSB Industries West**  **Nitric Acid Plant in 2011** 

### Figure **4 .**  **LSB Industries DMW Nitric Acid Plant in 2011**