CO2 removal from biogas bywater washing system

Abstract

CO2 removal from biogas by water washing system was investigated with various parameters, including liquid/gas ratio, pressure, temperature, and CO2 content. The results indicate that CO2 removal ratio could reach 34.6%-94.2% as liquid/gas ratio increased from0.14 to 0.50. Increasing pressure (from0.8 to 1.2MPa) could improve gas purification with a constant inflow rate of gas. Temperature played a key role in the process and lower temperature in absorption tower was beneficial for reducing CO2 content. CO2 removal ratio could reach 24.4%-83.2% when CO2 content in the simulated gas was 25%-45%. The lowest CO2 content after absorption was 2.6% at 1.2MPawith 400 L·h-1 gas flowand 200 L·h-1 water flow, which meets the requirement of CO2 content in natural gas for vehicle fuel.