Nanofiltration (NF) membranes have applications in several areas. NF can be used to treat all kinds of water including ground, surface and/or used as a pretreatment for desalination. NF membranes have been shown to be able to remove chemical oxygen demand (COD), turbidity, microorganisms and hardness, as well as a fraction of the dissolved salts. Similar to other membrane processes, a major problem in NF membrane applications is fouling. Several studies have been investigated for reducing the fouling phenomenon in NF membranes and suggested several methods for minimizing and controlling the fouling of NF membranes. This study aimed to evaluate the potential application of N for treatment in ground water of south of Quchan. The permeate fluxes of NF membrane at different feed flow rates, pressures and time were measured on a laboratory scale, using naofiltration pilot plant. The results show that by increasing the pressure as driving force on membrane filtration, the permeate flux increases. For instance, at a constant flow rate of 4.7 l/min, increasing transmembrane pressure from 8 to 20 bar causes a sharp increasing in permeate flux. The permeate flux at 20 is 2.8 times more than 8 bar operation. Also increasing flow rate leads to the reduction of concentration polarization effects and consequently increases permeate flux. At a constant pressure of 20 bars permeate flux for 14.7 is 1.9 times more than 4.7 l/min.

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