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Keeping the water flowing

| By Chemical Engineering

Currently, there are around 13,000 desalination plants in operation or under construction in 150 countries, according to the Institution of Chemical Engineers (IChemE; Rugby, U.K.; A number of these plants are in, or are planned for, locations that might surprise some of us. In the U.S., the Carlsbad Desalination Project (California;, described as the largest seawater desalination plant in North America, is expected to provide 50 million gal/d of desalinated seawater to San Diego County. The plant is scheduled to start up in 2016. IChemE predicts that by 2050, desalination plants could become common on U.K. coastlines, and by that time, the number of desalination plants across the world is expected to more than double as population growth and other factors place an ever increasing demand on water supply.

By now, it is no surprise to anyone reading these pages that there is a growing focus on sustaining our global water supply. Researchers and engineers are working on ways to improve water and wastewater treatment processes, including desalination technologies to increase the freshwater supply. Some of the latest advances can be found in Chemical Engineering’s Chementator section. In April, for example, we reported on work being done at the Lawrence Livermore National Laboratory (LLNL, Livermore, Calif.; on capacitive desalination (A new way to desalt water without using RO or distillation, Chem. Eng., p. 11, April 2013). And researchers from the University of Texas at Austin ( and the University of Marburg (Germany; are developing a process, called electrochemically mediated seawater desalination, that promises to be an inexpensive way to desalinate small volumes of seawater (Desalination, Chem. Eng., p. 13, August 2013). In a recent press release, IChemE quotes Martin Currie, a member of IChemE’s Water Special Interest Group and independent water quality and treatment consultant with Aqueum, as saying, “Globally, water scarcity is such a critical issue, that sustainable desalination is one of the most important areas in which chemical engineers are safeguarding our futures.”

Meanwhile, market experts are predicting big opportunities for suppliers to water treatment applications. By aggregating forecasts from several of its water-related reports, the McIlvaine Company (Northfield, Ill.; concludes that about $2.7 billion will be spent on the membrane portion of desalination investments this year and the rest of the $8 billion expected to be spent on membrane systems will be on related equipment, such as valves, pumps, piping and other filtration equipment. And, according to the ARC Advisory Group (Dedham, Mass.; the water and wastewater industry presents one of the largest opportunities for automation businesses over the next 20 years.

The focus on water and wastewater extends to all applications including both municipal and industrial needs. In fact, these two applications are not mutually exclusive. As the chemical process industries (CPI) strive to limit their water use, and look for more efficient ways to treat and reuse wastewaters, they are also looking at treated municipal water as a water source. Several archived articles in Chemical Engineering go into these aspects in more detail. See, for example, Water Reuse and Conservation in the CPI, pp. 44–50, September 2008 (

And, for more insight into how difficult-to-treat CPI wastewaters are evaluated and treated, see our cover story in this month’s issue.

Dorothy Lozowski, Editor in Chief