Dow Water & Process Solutions

DOW™ Ultrafiltration Membranes Enable Reuse of Domestic Waste Water

Despite source water challenges, UF technology ensures quality reverse osmosis membrane performance

Edina, MN - November 18, 2008

In order to ensure quality reverse osmosis feed water, ShanXi DaTong Co-gen has selected DOW™ Ultrafiltration membranes for its DaTong, China co-generating plant. Despite challenges posed by high chemical oxygen demand, the ultrafiltration (UF) membranes successfully demonstrate reliable performance with product water of turbidity averaging 0.05 Nephelometric Turbidity Unit (NTU) and silt density index (SDI) of less than one.

Located in the ShanXi province of China, the facility has supplied more than 300 megawatts of heat and electricity to local communities and industries for the past 50 years. In order to meet the increasing demand for energy, DaTong required an economical and efficient solution for municipal waste water treatment. The site was able to maintain acceptable feed water quality for reverse osmosis using only a prescreen and DOW Ultrafiltration modules as pretreatment. No coagulation, sedimentation, or sand filtration pretreatment unit operations are needed.

"Knowing how to effectively integrate world-class technology, such as ultrafiltration and reverse osmosis, allows Dow to assist municipalities such as ShanXi," said Christina Fang, area commercial development manager, Dow Water Solutions. "The stable product water turbidity and low SDI-consistent since November 2006-in addition to the system requiring chemical cleaning once every six to eight months, demonstrates the reliability and quality of DOW Ultrafiltration."

To learn more about DOW Ultrafiltration, or view this case study in its entirety, visit www.dowwatersolutions.com.

About Dow Water Solutions

Dow Water Solutions is a performance-based business unit comprised of world-class brands and enabling component technologies designed to advance the science of water purification around the world, including seawater desalination, contaminant removal and water reuse. With more than 1,000 employees worldwide, the business maintains five production facilities globally to manufacture, market and sell reverse osmosis membranes, ion exchange resins, titanium-based arsenic removal media, ultrafiltration, and electrodeionization components. Dow Water Solutions also manufactures, markets and sells premier water purification systems in China.

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For Editorial Information:

Karen Jayne Leinberger
The Dow Chemical Company
1.952.897.4364

Gardner Hatch
Gibbs & Soell, Inc.
1.212.697.2600
ghatch@gibbs-soell.com