MEMORANDUM

Date: September 27 , 2010

Subject: Site Visit

– El Dorado Nitrogen, L.P

Baytown, Texas

Nitric Acid Manufacturing NSP S Review

EPA Contract No. EP

- D

- 06

- 118; EPA Work Assignment No. 4

- 0 3 RTI Project No. 0210426.00 4 .0 0 3

From: Melis sa Icenhour

To: Bill Neuffer

EPA/SPPD /MMG (D243

- 02) U. S. Environmental Protection Agency Research Triangle Park, N.C. 27711

I. Purpose

The purpose of this visit was to observe the nitric acid manufacturing process at the

El Dorado Nitrogen facility in Baytown, Texas, and to collect information on sources of nitrogen oxide (NO X ) emissions and abatement controls in support of the review of new source performance standards (NS PS ) for the nitric acid manufacturing industry.

II. Place and Date

El Dorado N itrogen, L.P

8 4 90 W. Bay Road Baytown

, Texas 77522

- 2469 May 12, 2010

III. Attendees

The Fertilizer Institute (TFI)
Chris Leason, TFI Counsel Bill Herz, TFI President2

El Dorado Nitrogen, L.P Jerry Davis, Plant Manager Mike Barber, Process Manager

LSB In dustries Chuck Nestrud, outside counsel for LSB Industries John Carver, Vice President of Safety and Environmental Compliance

Baye r Material Science Gregg Stansfield , Fenceline Operations Manager

HSG Environmental Consultants

Ken Green

U. S. Environme ntal Protection Agency

Bill Neuffer

Tina N d oh

Mausami Desai

Nathan Frank

RTI International

Melissa Icenhour

IV. Discussion

A. Background

The El Dorado Nitrogen, L.P. facility in Baytown, Texas, manufactures nitric acid. The site of the plant is owne d by Bayer Corporation but El Dorado Nitrogen, a subsidiary of L SB

Industries

, serve s as guest operator to produce feedstocks for use by Bayer. The nitric acid produced on

- site is not used for fertilizer but is used for industrial chemicals. The facility contains a computerized, dual pressure, single train process that produces 65% nitric acid. According to Mr. Davis, a dual pressure process is usually chosen when the nitric acid concentration is greater than 65% and production is greater than 900 tons pe r day. The highest concentration of nitric acid from single pressure processes making nitric acid for producing

fertilizer is typically 58%.

The Bayer Material Science plant began operating about 1960 and is about a mile long. Bayer’s older nitric ac id unit was torn down prior to 1999 when the current operation was built.

The plot size of the plant is approximately 300 feet by 400 feet. The plot size limits expansion possibilities

.

B. Introductions and Presentation

All attendees began with a bri ef introduction including their involvement in the regulatory process . Jerry Davis then gave a presentation that covered the nitric acid production3

process; permit limits; the chemis try used to produce nitric acid; the use of selective catalytic

reductio n (SCR) for emission reductions; startup

, shutdown, an d malfunction (SSM) operations; and emissions that originate from other sources than the absorption column. Attachment 1 is a

non

- confidential version of the presentation given by El Dorado Nitrogen, L. P. The following paragraphs supplement the information presented in the attachment.

C. Process

The process at the Baytown, Texas plant is typical in the chemistry of nitric acid production but atypical in design. The first step in nitric acid product ion, oxidation of ammonia to nitrogen oxide, is typical. The ammonia supply to the process is about 0.29 tons of ammonia per ton of nitric acid.

The second step, oxidation of nitrogen oxide (NO) to nitrogen dioxide (NO 2 ) is atypical in design. The amou nt of nitrogen dioxide produced during the second oxidation step is more important at this plant than other plants where the nitric acid is used for fertilizer production. In order to meet the requirements of their client, the El Dorado Nitrogen plant mus t produce nitric

acid at 65% concentration. T o reach this concentration and maintain environmental compliance

, the plant must increase the amount of nitrogen dioxide created during the second oxidation step. The only way to increase the yield of nitrogen dioxide is to increase the time wherein the oxidation can take place. While oxidation only takes a few seconds, the material process flow through pipes and equipment is rapid . The process design increase s the amount of piping

between the beginning of th e second oxidation step and the absorption tower. For example, if the gas flow through the pipes were 300 feet per second

, there must be 300 feet of pipe for every second of oxidation time needed during the second step. The increased amount of pipe area

serve s as oxidation reactors

. As a result, this nitric acid plant look s a bit different than typical fertilizer type nitric acid plants

.

Another difference between the typical nitric acid plant and the El Dorado Nitrogen plant is the availability of hi gh pressure steam. At typical plants, shutdown of the nitric acid process also results in shutdown of the steam turbine, compressors, the expander, and any abatement technology. It takes time when starting the plant to create enough steam to operate the steam turbine/compressor train and increase the process pressure to allow absorption of the nitrogen dioxide. Until there is enough steam for absorption to take place, the nitrogen dioxide is emitted

instead of reacted.

Bayer owns the site of the El Dor ado Nitrogen plant and also has other types of chemical processes nearby. These other chemical processes offer a n unlimited amount of steam that can be accessed by the El Dorado Nitrogen plant at any time, which allows the compressor train to

run even if the nitric acid process is not running . Thus, the facility can remain in compliance with hourly NO X and ammonia concentrations at all times, even during periods of startup and

shutdown.

The third difference between the El Dorado Nitrogen plant and a t ypical nitric acid plant is the absorption tower. A typical absorption tower is about 15 0 feet tall and operates at a pressure of 150 pounds per square inch gauge (psig). The El Dorado Nitrogen absorption tower4

is 210 feet tall , has 34 trays, and operate s at a pressure of 170 psig. The design of the SCR deNOX system is based on an inlet concentration of NO X of 600 ppm. The unli mited steam that

can be accessed on

- site also allows the absorption tower and SCR to remain operating and thus

reduce the amount of nitrogen dioxide that is emitted from the plant during typical startup and

shutdown operation s

.

Process maintenance includes changing the ammonia oxidation catalyst about every 6

months as it loses activity and becomes brittle , causing loss of precio us metal catalyst . The plant generally undergoes an extensive maintenance shutdown every two years.

D

. Emissions and Controls

Emissions from the absorption tower in clude nitrogen oxides (NO X ) and nitrous oxide (N 2 O). The nitric acid production process is controlled by SCR at 650 oF , which controls NO X emissions but does not control N 2 O emissions. The catalyst used in the SCR system typically has a longer life than a catalyst used in a nonselective catalytic reduction (NSCR) system. The

amount of cata lyst used in the SCR system depends on the ratio of NO to NO 2 . If the ratio is higher than 50%, the amount of catalyst should be increased.

The plant has the following permit limits:

• Ammonia (NH 3 ) slip of 20 ppmv (hourly and annual average),

• NO X emissio ns of 23 pound per hour, and

• NO X emissions of 71 tons per year.

The plant uses a Grande Paroisse z eolite catalyst, which may cause nitrous oxide (N 2 O) formation. The plant has no permit limits for N 2 O.

The capital cost of the unit in 1999 was about $ 80 million

. The SCR catalyst typically costs $500,000 and has a life expectancy of greater than 10 years.

The plant uses extractive Fourier Transform Infrared (FTIR) technology to monitor NO,

NO 2 , NH 3 , and N 2 O emissions.

The plant has 5 nitric acid storage tanks operating at slight negative pressure . The vapor emissions from the tanks are controlled by a packed bed scrubber with hydrogen peroxide

solution . The liquid effluent from the scrubber is recycled. Some NO X and acid mist are

emitted.

Typ ically the plant emits pollutants in the following concentrations:

• N 2 O

— 1200 ppm,

• NO 2

— 10 ppm,

• NO

— 10 ppm, and

• NH 3

— 1 ppm.5

E

. Conclusions

This plant is relatively new, efficiently designed, and has low NO X emissions

. T hese factors made this plant an idea l candidate for a site visit. Industry representatives who attended this site visit and presentation stated that the plant is not a typical nitric acid plant and the low emissions achieved by this plant are not achievable by all nitric acid plants.

## Attachment 1

Non

- Confidential Presentation

P rovided by El Dorado Nitrogen, L.P.