Scott B. Mccray

Small-scale membrane systems for the recovery and purification of water

Abstract The availability of high-quality membrane modules in a variety of configurations has expanded the range of potential applications for membrane systems. These expanded capabilities make it possible to use membrane systems to solve separation problems that previously could not have been addressed using membrane-based technology. This paper describes the development of three innovative membrane systems for water-recovery applications for the National Aeronautics and Space Administration and the U.S. military. For each membrane system, the separation problem is outlined, the technology and system are described, the operating data are reported, and potential spinoff applications are discussed.

Concentration of Synfuel Process Condensates by Reverse Osmosis

In this paper the authors will discuss the use of a novel, fouling-resistant, inside-skinned hollow-fiber membrane configuration as an energy-efficient and cost-effective alternative to conventional treatment of synfuel process condensate waters. Reverse osmosis has been used in the past only to polish condensate waters that were first treated by conventional means. In the work described in this paper, a reverse-osmosis system actually replaces traditional biotreatment of condensate waters or replaces the solvent-extraction process in the treatment train. The membranes used in this reverse-osmosis system are capable of rejecting at least 90% of the phenols as well as high percentages of other organics contained in actual process condensate waters. Furthermore, these membranes have operated for several months on synfuel condensate waters and showed no significant decrease in performance. Energy and cost estimates of a reverse-osmosis system based on such membranes will be discussed in detail, including a comparison of operating costs of this system with the operating costs of conventional treatment systems.