New US Navy RO units 'will use 65% less energy'
The United States Office of Naval Research (ONR) is planning to build prototype desalination units that will use 65% less energy and be 40% smaller by weight than current Navy reverse-osmosis (RO) units, an ONR release on 23 September 2009 predicted.The units will be used for forces afloat, marine corps expeditionary forces and humanitarian missions ashore.
Delivering drinkable water for ships at sea and marines ashore for less cost and less energy became an ONR priority in 2004 under the Expeditionary Unit Water Purification Program (EUWP). Since its inception, the EUWP has produced advances in desalinization capability.
The first generation EUWP technology demonstrator has been used in a number of humanitarian missions. In 2005, it was deployed in support of the navy's response to Hurricane Katrina where it delivered safe drinking water to residents on the Gulf of Mexico coast being treated at a hospital in Biloxi, Mississippi.
The second generation EUWP Gen II technology demonstrator, built with shipboard constraints imposed on the design, is a larger, more stationary demonstration unit, and has potential for use by isolated communities. It has been tested successfully at the Seawater Desalination Test Facility at the Naval Facilities Engineering Service Center in Port Hueneme, California.
Port Hueneme is, of course, also the test site for the Affordable Desalination Consortium, which, since 2005, has sought to demonstrate lower energy consumption for (RO) desalination technologies among its other goals (See D&WR August/September 2008). The Naval Facilities Service Engineering Center is a consortium member.
Armistead anticipates increased capabilities from the newer demonstration unit. "From current Navy desalination systems we only get 20% product water," he said. "That means for 1,000 gallons of feed water, we would get only 200 gallons product water. These new systems will likely double that."
Michelle Chapman, a physical scientist with the US Bureau of Reclamation, is a member of the ONR team managing the research program observes, "Several of the projects we have funded have turned into patents for commercially available products and processes that are available for use in water desalination systems for communities where freshwater sources are not available."
Based on the successes in the EUWP program, the Advanced Shipboard Desalination, Future Naval Capability Program will begin in 2010. Navy Surface Warfare Center Carderock Division, Ship Systems Engineering Station (NSWCCD-SSES), is a partner in this effort. According to Dave Nordham, a NSWCCD-SSES mechanical engineer, "Any sort of technology advancements we find for ships are directly applicable ashore and can be utilized by ever-increasing drought ridden areas."
Key partners in the EUWP program include NSWCCD-Philadelphia, US Army Tank Automotive Research Development & Engineering Command, US Bureau of Reclamation and the Naval Facilities Engineering Service Center's Seawater Desalination Test Facility at Port Hueneme.