Abstract: A reverse osmosis membrane, and methods for making and using the membrane. The membrane has a continuous, defect-free, non-porous, hydrophilic coating that reduces the susceptibility to fouling.

Abstract: A membrane separation process and system for removing a component from a fluid stream. An auxiliary membrane module or set of modules is installed across the pump that drives the main membrane unit, so that the permeate streams from the main and auxiliary membrane units are mixed and pass together through a common driving pump. The concentration of the mixed permeate stream is allowed to build up by circulating the stream through the auxiliary unit. When the concentration has reached a desired level, the mixed stream can be tapped and the product stream drawn off.

Abstract: A membrane separation process and system for removing a component from a fluid stream. An auxiliary membrane module or set of modules is installed across the second stage of a two-stage membrane separation system. The driving force for the auxiliary modules is provided by the pump or other driving unit for the first membrane stage. The auxiliary module or modules provides additional treatment of the residue stream from the second membrane stage, but are driven by the first stage driving unit. The invention is particularly useful in any membrane separation operation involving gas separation, vapor separation or pervaporation in which a two-stage system design is to be used, and where it is desirable to improve the efficiency of the two-stage system.