Power consumption progressively increases with increase in pressure drop.

 The pre-coat filtration is semi-automatic as a filtration-aid for additional solid waste generation and also contributes to increase in TOC in brine.

 The quality of brine from pre-coat still has suspended solids generally over 0.5 ppm. This has a long term negative effect on secondary brine resins and electrolyser membrane.

 The conventional system of anthracite and precoat involves extensive cost for installation and maintenance but still generates additional solid wastes.

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PRODUCT DESCRIPTION :
The system consists of Ultrafiltration membranes which are designed for particulate removal in the brine stream. Due to tiny opening 0.05 microns) in the membranes all suspended particles including Calcium, Magnesium Silica , and organics are retained, while permitting the passage of clear brine. The particulates thus separated get deposited inside the membrane lumen and are periodically removed out of the system by a change in the direction of the brine flow. (back wash)

Ultrafiltration membranes are also very effective in the removal of colloidal organics and are an excellent pretreatment tool for the treatment of brine in Chlor-alkali Industry.

The Ultrafiltration system can replace the conventional anthracite and precoat filters. The brine from the Ultrafiltration system is ultrapure with respect to the suspended solids.

ULTRAFILTRATION : Brine from the clarifier is to be taken directly to the ultrafiltration unit without any media filter. The system operates in the following sequence:

UF Feed          UF Product

Filtration Backwash During backwash the accumulated particulates are collected and flushed out of the system. The brine from the backwash steps are collected and taken back to the clarifier. They contain only suspended solids. Hence, practically there is no wastage of brine. Chemical cleaning is required when the differential pressure across the membrane system increases beyond 0.7 kgs/cm2 (10.5 psig) Acidified depleted brine is used for chemical cleaning. The chemical wash is collected in a separate tank , neutralised for acidity and free chlorine and fed to the saturator. The operation can be controlled by a Programmable Logic Controller, from the Central Control room.

 ECO-FRIENDLY AS THERE IS NO EFFLUENT GENERATION.

 SUBSTANTIALLY REDUCES FOOT-PRINT AREA.

 REDUCES SOLID WASTES.

 REDUCES TOC IN THE FEED BRINE TO SECONDARY RESIN TOWER DUE TO ELIMINATION OF FILTER AIDS.

 INCREASE IN THE EFFICIENCY OF THE ION EXCHANGE COLUMNS DUE TO LOWER SUSPENDED SOLIDS CONTENT.

 DUE TO PHENOMENOL DECREASE IN THE SUSPENDED SOLIDS, THE LIFE OF THE ION EXCHANGE MEMBRANE WILL INCREASE.

 THE UNIT IS PLC OPERATED,MINIMUM MANPOWER REQUIRED.

 CONSISTENT QUALITY OF PRODUCT BRINE IRRESPECTIVE OF FLUCTUATIONS IN FEED BRINE QUALITY FROM THE CLARIFIER.

 REDUCES LARGE PIPING.

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SAVINGS :

Power savings < 0.2 kwH/cum   Reduction in man-power   Elimination of Anthracite filter   Elimination of Alpha Cellulose System.   Reduction in (make up) Ion Exchange resin.

  Savings in Consumption of chemicals - HCl, NaOH

  Reduction in maintenance of Alpha cellulose and Anthracite filter.

Total saving - direct and indirect : Cost approx. Rs. 3.5 Million (US$ 7440)/ year for typical 100 T/day plant

The above savings are without taking into consideration the indirect benefits like reduction in TOC and secondary brine pressure drop and thereby resulting in power saving and enhancement in the life of resin and membrane.

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