Experimental investigation and simulation of hollow fiber membrane process for SF_6 recovery from GIS

摘要

In this present study, polyethersulfone hollow fiber membrane was used to recover sulfur hexafluoride (SF_6) from gas-insulated switchgear (GIS). SF_6, N_2 pure gas and mixed gas (12.5 vol.% of SF_6) experiment was initiated to observe permeation behavior according to temperature and pressure difference and retentate flow rate. Scanning electron microscopy was used to investigate the morphological characteristics and the structure of asymmetric hollow fibers. The permeation rates of SF_6 and N_2 were measured by the variable pressure method. As a result, permeance of N_2 was 9.5-16.3 GPU, and selectivity of N_2/SF_6 was 10.5-13.3. Moreover, the concentration of SF_6 in the retentate stream reached to 99.2% by the control of the operating condition. Based on the experimental results, tree-stage membrane process was designed using simulation program. As a result, demanded membrane area reduced about 74% according to operating condition difference.