Tubular Reverse Osmosis Membrance Research.

摘要

The report concerns the development of tubular NS-100ultrathin composite membranes capable of demonstrating single-pass seawater desalination while contained within flexible,braided pressure supports and investigates ultrafiltration as pretreatment for the reverse osmosis desalination of seawater. A flexible braided sleeve was used as a membrane pressure support. Through proper selection of yarn and membrane diameter and precise control of the braiding process dimensional stability requirements were met. Uniform tubular extrudate was continuously cast in a reproducible manner by a solution extrusion-gelation process. The mechanical properties of the substrate material were evaluated by tensil tests and the internal structure was examined from SEM cross-sectional photographs. Optimum conditions for coating and crosslinking polyethylenimine film on the inside of the polysulfone tube were developed for maximum performance. A rapid procedure was developed for characterizing ultrafiltration (UF) permselectivity characteristics in terms of molecular weight cut-off properties. Cost comparisons were made between the pretreatment of seawater by ultrafiltration and by conventional means. (Modified author abstract)