Pressure Swing Permeation:Novel Process for Gas Separation by Membranes

摘要

A novel process for gas separation, called pressure swing pem1eation, was investigated to elevate the relatively low penneate pressure by pressurization with high-pressure feed gas, thereby reducing or eliminating additional penneate compression costs where a pressurized penneate is required. This process uses two or more membrane modules and operates in a cyclic fashion, with each module repeatedly undergoing the sequential steps of feed admission and penneation, residual removal, penneate reception, penneate pressurization, and product withdrawal. The unsteady-state penneation associated with pressure swing penneation was studied parametrically, and a bench-scale unit compro- mising two hollow-fiber membrane module." in parallel was tested for H 21N2 separation to demonstrate the effectiveness of the process. The pemzeate product at a pressure as high as the feed pressure can be produced without using a compressor. This is impossi- ble with traditional steady-state processes where a pressure differential across the mem- brane must be maintained. The pressure swing pemleation is analogous to pressure swing adsorption and has the potential to be synergistically integrated with the pressu~ swinJ! adsol1Jtion process for enhanced separation of gases.