Concentration of Synfuel Process Condensates by Reverse Osmosis

Abstract
In this paper we 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.