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集约化畜禽养殖场厌氧发酵过程中产生的大量H2S具有潜在的危害。本文以某畜禽养殖场的新鲜猪粪为研究对象,通过添加不同比例的赤铁矿和氧化镁,模拟猪粪厌氧发酵过程中对H2S产生和释放的影响。在18 d的持续实验中,对发酵液中pH和发酵气体中H2S浓度变化进行全程监控,结果表明:添加赤铁矿对发酵体系的pH无明显影响,而添加氧化镁可显著提高发酵体系的pH值;添加2种矿物越多,气体中H2S含量越低。推测2种矿物对H2S产生的抑制在机制上有所不同。赤铁矿主要通过还原分解消耗H+和沉淀消耗S2-的方式抑制H2S的产生;氧化镁则主要通过提高体系pH值,抑制SRB的活性以及降低H2S在气相中的分配。“,”Anaerobic fermentation in intensive farms can produce large amount of H2S which is potentially hazardous.This study designed experiments to investigate the effects of hematite and MgO on producing and releasing H2S in anaerobic fermentation system.Fresh swine manure was taken to be the fermentation material.Changes of pHs and H2S concentrations were monitored during 18 experimental days.The results showed that at the beginning of the experiments,the pH of fermentation system changed little with the addition of hematite,while much with the addition of MgO.After the experiments,it was discovered that both hematite and MgO suppressed the pH decrease and H2S production.The results indicated that hematite and MgO act differently in the suppressing of H2S production.The suppression of H2S production by hematite was through consuming H+ and S2-which was vital for the formation of H2S,while by MgO was through elevating pH of the system,which could then suppress the activities of sulfate reducing bacteria and the hydrolyze of S2-.