Overview of Current Practices in Desalination Facilities

Abstract

With freshwater sources already over-allocated, regions needing to meet increasing water demand are considering supplies that were previously uneconomical to treat, such as brackish groundwater and surface water, polluted water, agricultural runoff, reclaimed municipal and industrial wastewater, and seawater. In addition, increasingly stringent discharge regulations and identification of emerging contaminants are requiring wastewater utilities to implement advanced water treatment technologies. One such technology is desalination to remove dissolved constituents, including those contributing to salinity. According to Global Water Intelligence, the rate at which desalination of various water sources is being implemented has increased rapidly in recent years: 1,320 mgd in 1980; 4,000 mgd in 1990; 7,500 mgd in 2000; and 15,000 mgd in 2010, including facilities under design. The growth is spurred by an increased demand for water, a lack of alternative sources, improved technology, and decreased costs. This article highlights current seawater reverse osmosis practices revealed in a recent Water Research Foundation survey.