Energy-Efficient Hybrid Water Purification System

Today"s military must be highly mobile and carry all necessary equipment and supplies with them. A major limitation to mobility is the need to carry fresh water. Although there are military systems that can treat any source water for drinking, their size, weight and large energy requirements often make them impractical for use by small units and forward operating bases. What is needed is a mobile, light weight, energy efficient (<20 Wh/gallon) water treatment system that can treat water from any source to produce water that meets military drinking water standards. In Phase I we built a proof of concept breadboard unit to demonstrate a hybrid water treatment system can desalinate seawater to less than 500 ppm total dissolved solids, and when run in fresh water mode, treat source water to 15-minute silt density index values of less than 3.0 and turbidity values less than 1.0 NTU. From this work we were able to accurately show a pathway to meet the weight, volume and energy metrics for the system. In Phase II, we will design and build prototype systems capable of producing 300 gallons per day of seawater that weigh less than 500 pounds and take up less than 25 cubic feet of volume.