Membrane separations are one of the latest techniques widely used in industries in recent years. Its efficiency, low requirement of energy and possibility of hybrid processes makes it better than the conventional processes. The major problems in the membrane processes are flux decline, fouling and concentration polarization due to deposition of solids on the membrane surface. In present work, ethylene glycol-water solution of PCP chemicals Pvt. Ltd. containing large amount of sodium sulphates was treated with HPA-150 nanofiltration membrane on flat sheet module pilot plant. Due to high salt concentration, fouling occurs and the membrane was clogged. Thus solution was diluted and then treated and the effect of dilution was studied. It results in increase in flux and decrease in concentration polarization and thus fouling. The effect of different pressure on the flux and rejection were studied. The flux increases with increase in pressure. Effect of dilution is also studied. The flux increases with the dilution factor and the rejection decreases with dilution factor. Cleaning of the membrane can be done by chemical methods using 2% (w/v) citric acid and 2% (w/v) EDTA solution. The effect of cleaning with both the chemicals was studied and flux recovery was calculated. The flux increases as compared to that with ethylene glycol-water solution, but does not recover completely due to irreversible fouling. The flux recovery after cleaning with 2% (w/v) citric acid solution is around 56% and after cleaning with 2% (w/v) EDTA is around 70%.
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