中试级沼气膜精制纯化关键部件—膜组件设计与实验研究

Design and Experiment of Membrane Module for Pilot Scale Biogas Membrane Purification

文章基于串并联二级膜渗透气回流重脱技术,设计并研制了处理气量为50 m^3·h-1的中试级内压逆流型沼气精制膜组件。研究结果表明:当进气压力为1.0 MPa时,只用一级膜分离纯化时,产品气CH4的含量可高达89.34%,其回收率约71.62%;当采用二级膜分离纯化时,产品气CH4的含量最高可达96.63%,其回收率约85.24%;当其它条件不变时,采用二级膜渗透气回流重脱方案,产品气甲烷回收率比不采用此方案可从71.62%增至85.24%。按某厂日产1万m^3沼气计算,由技术经济分析可知,采用二级膜渗透气回流重脱方案,相当于每天可挽回636 m^3车用压缩燃气,即每天可供4辆出租车用气。该试验为应用沼气膜精制提纯技术装备将低质低值沼气向高品质天然气级燃料转化提供了技术支持。

Based on osmotic gas reflux stripping technique with series and parallel two stage membrane,a pilot scaled internal pressure countercurrent biogas-refining membrane system with a gas treatment capacity of 50 m^3·h-1 was designed and developed in this paper. The results showed that,when the inlet pressure was 1. 0 MPa,and with only one stage membrane separation and purification,the CH4 content of product gas reached 89. 34%,and its recovery rate was about71. 62%. When the two stage membranes were used,the CH4 content of product gas could be as high as 96. 63% and its recovery rate was about 85. 24%. When the osmotic gas reflux stripping technique with series and parallel two stage membrane was adopted and the other conditions are the same,methane recovery rate of product gas increased by 12% comparing with that without adopting the technique,from 71. 62% to 85. 24%. This experiment provides technical support for the conversion of low-quality and low-value biogas to high-quality natural gas fuel by applying biogas membrane purification technology.