生物催化氧化法脱除H_2S的填料选择研究

Packing media of oxidative biofilter for H_2S removal

针对H2S污染的严峻形势,构建了包括催化再生装置和生物滴滤器的生物催化氧化装置,进行了装置的填料选择研究。经对比试验得出填料脱硫性能的优劣顺序为:沸石>焦炭>多面空心塑料小球。在温度为30℃、进气量为0.25m3/h、进气H2S为2000mg/m3、喷淋量为1000mL/h、喷淋液的pH为1.97、Fe3+为0.05mol/L的条件下,装填沸石的生物催化氧化装置的出气H2S浓度足以达到《恶臭污染物排放标准》(GB14554—93)规定的一级厂界标准值。试验证明,生物催化氧化法是有效的新型脱除H2S技术,具有良好的经济、社会及环境效益,应进一步开展中试研究。

The biocatalytic oxidation system for gas phase desulfurization included an oxidative biofilter, in which H2S was removed by biooxidation by Thiobacillus ferrooxidans and chemical oxidation by Fe^3＋ present in the recirculating scrubbing liquid, and a reactor for catalytic regeneration of Fe^2＋ . Natural zeolite, coke, and plastic balls （20-30 mm dia. ） were compared as the material of the biofilter packing media based on the cost and H2 S removal. Effects of packing depth, influent H2 S concentration, and the scrubbing liquid flowrate were also considered. The study results show the natural zeolite was thc best packing material, followed by coke and the plastic balls. Under the treatment conditions of： temperature = 30 ℃, influent flowrate = 0.25 m^3/h, influent H2S = 2 000 mg/m^3 , liquid flowrate = 1 000 mL/h, pH= 1.97, CFe^3＋ =0.05 mol/L, the effluent H2 S concentration was below the national discharge limit of GB 14554 93. The biocatalytic oxidation system was very cost effective for removing H2 S from a gaseous influent. The attractive economics of this desulfurization system should be validated in an onsite pilot scale demonstration.