SEPARATION OF OXYGEN FROM SEAWATER BY MEMBRANE PERMEATION

A RELIABLE METHOD OF EXTRACTING DISSOLVED OXYGEN FROM SEAWATER IS REQUIRED FOR A NUMBER OF NAVAL APPLICATIONS. THIS PROPOSAL DESCRIBES THE DEVELOPMENT OF A MEMBRANE SYSTEM TO PERFORM THIS SEPARATION. IN THIS SYSTEM, SEAWATER CONTAINING DISSOLVED AIR IS BROUGHT IN CONTACT WITH A SUITABLE SELECTIVE MEMBRANE, AND A PARTIAL VACUUM IS APPLIED TO THE OTHER SIDE OF THE MEMBRANE. WATER AND DISSOLVED AIR PERMEATE THE MEMBRANE. THE WATER IS CONDENSED, PRODUCING A POTABLE WATER STREAM AND LEAVING AN OXYGEN-ENRICHED AIR STREAM. WE WILL USE THIN-FILM COMPOSITE POLY(DIMETHYLSILOXANE) OR ETHYLCELLULOSE MEMBRANES ALREADY PRODUCED AT MEMBRANE TECHNOLOGY AND RESEARCH, INC. (MTR), FOR THIS APPLICATION. IN THE PHASE I PROGRAM, THE TECHNICAL FEASIBILITY OF THE APPROACH WILL BE DEMONSTRATED USING A SMALL-BENCH SCALE SYSTEM AND 0.2-M(2) SPIRAL-WOUND MEMBRANE MODULES. BASED ON THESE RESULTS, A PRELIMINARY DESIGN ANALYSIS OF A UNIT FOR A 50PERSON SUBMARINE CREW WILL BE PERFORMED. IN A PHASE II PROGRAM, A COMPLETE PILOT UNIT SUITABLE FOR FIELD EVALUATION WOULD BE PRODUCED.