CA-EN
The plant is slated to produce 660,000 ton/year of caustic soda 100% or its equivalent 1,320,000 ton/year of caustic soda 50%. the plantconsists of two lines each producing half of the overall output. Its major feedstock is brine with a density of 300-310 gr/lit. Thisrequired feed is obtained by processing 1,196,000 t/y of washed

 Salt from the Sarbandar salt pond.

The plant can be classified into four major sections:

1-Brine filtration and precipitation

2-Cell room (electrolysis of sodium chloride)

3-Purification unit

4-Wastewater treatment

At the first section Na2 Co3

Sodium carbonate (Na2CO3)and sodium hydroxide (NaOH) are added to the input brine. Then, suspended solid impurities are settled and the brine is fed to the filtration unit where three different kinds of filters  namely anthracite, candle and ion-exchange filters are used

respectively to remove the suspended solid content, the dissolved solid content and  the calcium and magnesium impurities to a level of 20 ppb. (Due to the sensitivity of the membranes, the brine should have a high purity.)


The second section

Includes 24 BM 2.7 Electrolyzer. Each electrolyzerconsists  of 168electrolyzing cells 5 of which remain stays in stand- by mode.

In electrolyzing cells, the saturated brine will be decomposed electrically into CL- and Na+ with a current density of 5.46 KA/m2 and a current of 14.86 KA. Some amount of hydrogen is produced in the cathode

compartment of each cell.The CL- ions are oxidized and produce chlorine gas.And the Na+ ions, after passing through the membranes, combine with OH- ions and form NaOH or caustic soda.

The third section

Includes cooling, drying and concentration of chlor in which the chlorine gas produced by the electrolyzers will be pumped to the drying unit.

The out coming the chlorine gas will be sent to users.

At the concentration Unit, the 32% NaOH coming from the cells is concentrated ot 50%. This is then sent storage tank for sales.

In the acidification unit, portions of the freed hydrogen during hydrogen purification and the out coming chlor from the compressors are combined and burnt in a furnace. As a result, the obtained chloridric acid will convert to HCL in a column after absorbing water.

This will be used for the plants consumption. The combination of chlor and NaOH will produce sodium Hypochlorite.

In the water Treatment Unit, the waste water coming from various units will be neutralized and diluted. It is pumped to the nearby Fajr UT complex after its PH is regulated and its free chlorine is eliminated.