Reverse osmosis membrane fouling and its control

Reverse osmosis (<i>RO</i>) membranes can be used to treat ground water, surface water and wastewater, but a major problem in <i>RO</i> membrane applications is fouling. Many studies have investigated the mechanisms of fouling in <i>RO</i> membranes and suggested various methods to control the membrane fouling. This paper reviews several aspects of <i>RO</i> membranes, such as the types of membrane fouling, their effects on <i>RO</i> membrane processes and fouling control technologies, focussed on the appropriate feed pretreatment technologies and cleaning methods, especially on the membrane filtration pretreatment processes, including microfiltration (<i>MF</i>), ultrafiltration (<i>UF</i>) and nanofiltration (<i>NF</i>), which are the new trends in designing a pretreatment system in the application of <i>RO</i>.<br />