Reverse Osmosis Membranes for Desalination of Brackish Water

Abstract

Reverse osmosis (RO), which is commonly used for different water purification and desalination applications, is a remarkable process to separate dissolved inorganic and organic compounds from water. Over traditional methods of water treatment and purification, RO has many benefits such as production of high quality drinking water, simultaneous elimination of multiple pollutants, and simple operation procedure. As drinking water supplies are declining and demand for high quality water is increasing worldwide, RO membrane based water treatments will most probably continue to develop. This research was aimed at better understanding the behavior of the thin film composite (TFC) polyamide membrane used in RO process under various operating conditions. The performance of RO membrane was evaluated in terms of salt rejection and water flux to simulate brackish water desalination process. The operating conditions included salt concentrations ranging from 2000 to 6000 ppm and operating pressure ranging from 100 to 250 psi. Based on experimental results, the performance of the TFC polyamide RO membrane was estimated at higher operating pressures (300-1000 psi). Based on mass transfer coefficient , solute transport parameter and water permeability that is characteristic of the membrane. In addition, the potential of using the TFC RO membrane to process water during oil and gas productions (with 1.5-2.5 % salt by weight), was demonstrated in this study. Besides simulation, experiments were conducted using real water as the feed solution.