Hydrophobic Hollow-Fiber Membranes for Membrane Distillation Applications

1The Navy has been investigating membrane distillation (MD) as a means of desalinating seawater aboard ships since 1983. MD could potentially offer advantages over conventional distillation, the technology in most common use now, and could offer an alternative to other promising membrane technologies such as reverse osmosis. These potential advantages include small size, simplicity, and low energy requirements. MD is also relatively unaffected by salt concentration, not susceptible to fouling, and produces essentially pure water that does not need further treatment. MD has never been commercialized, primarily because no membrane has yet been developed specifically for this application. To render this technology available for full Navy consideration, we propose to develop an MD membrane and the accompanying module. In Phase I we will investigate the technical feasibility of developing a membrane that, when optimized during Phase II, would meet Navy Specifications for MD. During Phase I this membrane will be incorporated into a first-generation module and tested against the Navy specificatons. The results of this test will indicate whether the membranes are technically feasible and will specific targets for Phase II optimization. The ultimate goal of the program is to commercialize the proposed new technology to meet the needs of the Navy. We have established a spin-off company, Bend Membrane Technologies, to manufacture and market membranes based on our technologies. This company could offer an avenue for membrane manufacture in quantities that would meet those needs.