农村地区沼气净化脱硫的试验研究

[目的]探讨天然气膜法创新性分离技术在农村沼气脱硫中的应用。[方法]利用聚酰亚胺致密气体膜进行沼气脱硫,研究进气流量、膜两侧压差、进气温度和渗透侧压力等对脱硫效果和传质通量的影响,分析温度对分离效果的影响趋势。[结果]结果表明,含H2S为301 mg/m3的沼气,可将硫含量降至9 mg/m3以下,完全符合国家管输标准(<20 mg/m3)。单级膜组件在膜两侧压差为0.20 Mpa、进气流量为0.30 m3/h时,脱硫效率最高,达97%。进气温度25℃,原料气温度12~70℃,在气体流量0.64 m3/h,两侧压差0.21 Mpa时,H2S和CH4的传质速率相差6倍。[结论]聚酰亚胺致密气体膜通过改变工艺条件可有效脱除H2S酸气。

The Experiment Study on Desulfurization by Biogas Purification in Rural Area

[Objective]The purpose was to discuss the application of natural gas membrane method innovation isolation technique in countryside methane desulphurization.[Method]The polyimide compaction gas membrane for carrying out the methane desulfuration was used to study the effect of inlet gas flow,differental pressure in bilateral membranous wall,inlet gas temperature and infiltration pressure on the desulfuration effect and mass transfer flux.Influence trends of the temperature on the separation impact was analyzed.[Result]The results showed that sulfur content was decrease to 9 mg/m3 from 301 mg/m3,it accorded with national duct transport standard(<20 mg/m3).Desulfuration efficiency was the upmost of 97% when pressure difference in bilateral membranous wall was 0.20 Mpa and inlet gas flow was 0.30 m3/h.The discrepancy of mass transfer flux between H2S and CH4 wad 6 multiple under the conditions of inlet gas temperature of 25 ℃,raw material gas temperature of 12～70 ℃,gas flow of 0.64 m3/h and pressure difference in bilateral membranous wall of 0.21 Mpa.[Conclusion] The polyimide compaction gas membrane can effectively get rid of acid gas of H2S by changing craftwork condition.