乙醇对硫酸盐还原-甲烷发酵效率影响的研究 |
摘要点击 3375 全文点击 1615 投稿时间:2008-03-19 修订日期:2008-05-16 |
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中文关键词 硫酸盐还原菌 产酸菌 产甲烷菌 乙醇 协同作用 吹脱 |
英文关键词 sulfate-reducing bacteria (SRB) acidogenic bacteria (AB) methane-producing bacteria (MPB) ethanol cooperation stripping |
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中文摘要 |
针对硫酸盐还原菌(SRB)、产酸菌(AB)和产甲烷菌(MPB)的生态位特征,采用两级厌氧与循环气提吹脱工艺,以蔗糖和乙醇为有机底物(COD为6 000 mg·L-1),在不同COD/SO2-4时分别研究了底物中乙醇浓度对硫酸盐还原、有机物去除和甲烷发酵效率的影响,以及系统的硫化物吹脱效果和最佳回流率.结果表明,乙醇的添加可以促进SO2-4还原,并使COD/SO2-4降低产生的竞争性抑制作用减弱,SRB、AB和MPB菌群处于良好的协同代谢状态.乙醇/SO2-4从0提升至2后系统的处理效率明显改善,COD/SO2-4为12、 6和4时的SO2-4还原率分别由7.7%、 8.1%、 14.1%提高为84.7%、 87.6%、 82.5%,COD去除率由83.3%、 76.5%、 69.6%提高为92.8%、 93.5%、 89.7%,CH4/COD由225.7、 204.6、 178.6 mL·g-1提高至278.5、 253.7、 236.1 mL·g-1.系统经10倍回流水稀释及气提吹脱30%~55%的硫化物后,硫化物浓度分别低于27.8、 38.4、 52.4 mg·L-1,有效地抑制了H2S的毒性作用.但回流率偏大(20倍)使底物浓度梯度过低,SO2-4还原率下降;回流率偏低(5倍)使污泥床无法充分膨胀,COD去除率降低. |
英文摘要 |
Base on the different niche characteristics of sulfate-reducing bacteria (SRB), acidogenic bacteria (AB) and methane-producing bacteria (MPB), this experiment used two-stage anaerobic treatment and circular gas stripping. Sucrose and ethanol were used as organic substrate (COD=6 000 mg·L-1). The effect of ethanol concentration on sulfate reduction, COD removal and methanogenesis, the effect of sulfide stripping and the best recycle ratio were investigated respectively at different COD/SO2-4 ratios. The results indicate that the addition of ethanol promotes SO2-4 reduction, reduces inhibition of competition resulted from COD/SO2-4 decreasing, and makes SRB, AB and MPB in good synergetic metabolism. The efficiency of the system was improved obviously after ethanol/SO2-4 ratio enhanced from 0 to 2. When the ratios of COD/SO2-4 were 12, 6 and 4, SO2-4 reduction efficiencies increased from 7.7%, 8.1%, 14.1% to 84.7%, 87.6%, 82.5%, COD removal efficiencies increased from 83.3%, 76.5%, 69.6% to 92.8%, 93.5%, 89.7%, and CH4/COD increased from 225.7, 204.6, 178.6 mL·g-1 to 278.5, 253.7, 236.1 mL·g-1, respectively. Dilution at a recycle ratio of 10 and stripping 30%-55% sulfide controlled sulfide concentrations less than 27.8, 38.4, 52.4 mg·L-1, which inhibited effectively the toxicity of H2S. But higher recycle ratio (r=20) made substrate gradient too little and SO2-4 reduction efficiency reduced, while lower recycle ratio (r=5) made sludge bed shrunken and COD removal efficiency reduced. |