ZONE ONE

This zone consists of one 111-MTPD Ammonia, one 150-MTPD Urea, one 240-MTPD Soda-Ash, one 60-MTPD Sodium bicarbonate, and one 91-MTPD STPP plants. The in-built utility plant provides all the utilities for the process plants in this zone.

Sodium Carbonate plant
The Soda Ash plant with 180 MTPD nameplate capacity was started up in 1973. Subsequent expansion projects increased the production rate to 240 MTPD. Table salt and limestone are feedstock for this plant.

Soda-Ash is used in glass, paper mills, leather, food and textile industries as additive or feedstock.

STPP is the major constituent of detergents and their derivatives.

ZONE TWO

The major expansion project in the company was executed in 1984 by constructing Ammonia, Urea, Nitric Acid and Ammonium Nitrate plants of ten times in capacity as zone No. one . It also consists of bulk handling facilities for produced materials as well as utilities. The Hydrogen and Argon recovery unit was annexed to Ammonia plant in 1994.

AMMONIA PLANT

Ammonia is produced via steam reforming of natural gas. Natural gas at pressure of 43 bar is first desulfurized and then mixed with steam prior to let into primary reformer. Air is injected to secondary reformer in order to provide the synthesis gas with Nitrogen and also provides the necessary heat for further reforming of the exit gas for primary reformer. The carbon monoxide is converted to carbon dioxide in shift reactors. Carbon dioxide is washed and recovered by hot carbonate solution and sent to the Urea plant. The residual carbon oxides in the synthesis gas are converted to methane in Methanator prior to gas compression stage. The make up gas is converted to Ammonia in the synthesis loop and the produced ammonia is let down and sent to consumers while the unreacted gas is routed back to the reactor. The purge gas is dealt with in the Argon recovery unit and the Hydrogen rich gas is used as make up gas.

UREA PLANT

Ammonia and carbon dioxide are needed to make urea. The Urea plant is designed to produce 1500 MTPD urea. The ammonia and carbon dioxide is fed to the condenser to make Carbomate solution. It is then let to the reactor to be converted to urea. The solution thus formed is concentrated in series of evaporators and sent to prilling tower. Airflow in countercurrent direction (drafted by six fans) solidifies the urea prill drops and cools it to 88 degrees Celsius.

NITRIC ACID PLANT

Nitric acid is produced by air oxidation of ammonia on a platinum-based catalyst. The oxidation product is Nitrogen monoxide. It is further oxidized to nitrogen dioxide, which is then absorbed by water to form nitric acid.

AMMONIUM NITRATE PLANT

Nitric acid and ammonia are feedstock for this process. Ammonia is first vaporized in evaporator and then is mixed with nitric acid in the reactor to produce steam and ammonium nitrate solution. Vacuum evaporators are used to concentrate the solution thus formed. The 99.8% melt is poured into prilling tower via suitable showers. The prill drops are solidified and cooled by countercurrent airflow in prilling tower and fluidized cooler bed. Ammonium nitrate for industrial purposes is also produced in this plant.

ARGON RECOVERY UNIT

The ammonia purge gas is used to produce 15 MTPD technical grade (99.999%) Argon. It is used in welding as well as electrical bulb industry.

ZONE THREE
 

This zone consist of Methanol, Chlor-Alkali and Calcium Hypochlorite Plants.

During the imposed eight-year war with Iraq, the expansion project installations was transferred to Shiraz in order to safeguard the equipment. The plant was erected in the Shiraz site and started up in 1988. 180 MTPD Hydrochloric acid, and 40 MTPD Javelle water are possible products of this plant along with 60 MTPD liquid chlorine, and 68 MTPD caustic soda as fixed products.  

The products of this plant are used in food, cosmetics, Aluminum, water treatment, pulp and paper industries.

The calcium hypochlorite plant with a name plate capacity of 15 MTPD was constructed adjacent to chlorine plant in order to meet the demand for water disinfectant. The plant has been on stream since 1993.
 

METHANOL PLANT

The methanol plant was designed to produce 255 MTPD grade “AA” methanol. The plant has been operational since 1990. Steam reforming of natural gas is used for this process. Methanol is applied in synthetic fibers, plastics industries as well as melamine, insecticides and MTBE production.