厌氧生物滴滤法脱除冷煤气中硫化氢的研究

水煤气中硫化氢在燃烧时会转变成二氧化硫,对环境产生污染。文章采用厌氧生物滴滤塔法对冷煤气进行脱硫处理。因煤气对氧的严格限制,通过设计生物滴滤塔,经挂膜驯化后在厌氧条件下对浓度在1~5 g/m3左右的硫化氢进行脱除处理,考察滴滤塔运行条件对脱除效果的影响。结果表明,生物挂膜25 d后,生物滴滤塔达到稳定,喷淋液pH值为2.23,ORP值为283 mV,溶解氧为0.4 mg/L,对溶液中硫离子氧化效率达到94%。滴滤塔在液气比0.15,空塔气速0.088 m/s,pH值5.0~7.0,填料高度为82 cm,塔温为25~30℃左右时,达到较优的运行条件,此时该滴滤塔对以CO、CO2、H2和1 940 mg/m3H2S组成的模拟水煤气的脱硫效率达91.2%。

Removal of Hydrogen Sulfide in Cold Coal Gas by Anaerobic Bio-trickling Filter

Hydrogen sulfide in water gas would turn into sulfur dioxide when burnt,which would pollute the environment.Anaerobic biological filter method was used in desulfurization for cold coal gas.As the water gas has strict control of oxygen concentration,bio-trickling filter was designed for removing hydrogen sulfide about 1~5 g/m3 in water gas under anaerobic conditions after biological membrane hunged and domesticated.Effect of the filter operating conditions on removal efficiency was studied.Results showed that after biological membrane hanged and domesticated in 25 d,the bio-trickling filter became stable,spray liquid pH value was 2.23,ORP value was 283 mV,dissolved oxygen concentration was 0.4 mg/L,and oxidation efficiency of sulfur ion in the solution reached 94%.Under the optimal operating conditions as liquid gas ratio 0.15,aeration rate 0.088 m/s,pH value 5.0~7.0,packing height 82 cm,tower temperature 25~30 ℃,the desulfurization efficiency was 91.2% for 1 940 mg/m3 H2S in the simulated water gas consisting of CO,CO2,H2 and H2S.