乙醇对硫酸盐还原-甲烷发酵效率影响的研究  

Effect of Ethanol on Sulfate Reduction and Methanogenesis

作　　者：汪琦[1] 刘波[1] 闫懂懂[1] 李松[1] 陈泽智[1] 

机构地区：[1]南京大学环境学院,污染控制与资源化研究国家重点实验室,水处理与水环境修复教育部工程研究中心,南京210093

出　　处：《环境科学》2009年第3期924-929,共6页Environmental Science

基　　金：水处理与水环境修复教育部工程研究中心开放课题基金项目(WTWER0719)

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6000 mg.L-1),在不同COD/SO42-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SO42-还原,并使COD/SO42-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/SO42-从0提升至2后系统的处理效率明显改善,COD/SO42-为12、6和4时的SO42-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、236.1mL.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,SO42-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.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/SO^- ratios. The results indicate that the addition of ethanol promotes SOl- reduction, reduces inhibition of competition resulted from COD/SO^- decreasing, and makes SRB, AB and MPB in good synergetic metabolism. The efficiency of the system was improved obviously after ethanol/SO4^2- ratio enhanced from 0 to 2. When the ratios of COD/SO42- were 12, 6 and 4, SO4^2-- 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 mL·g-1, which inhibited effectively the toxicity of H2 S. But higher recycle ratio （ r = 20） made substrate gradient too little and SO4^2- reduction efficiency reduced, while lower recycle ratio （ r = 5） made sludge bed shrunken and COD removal efficiency reduced.

关 键 词：硫酸盐还原菌 产酸菌 产甲烷菌 乙醇 协同作用 吹脱 

分 类 号：X703[环境科学与工程—环境工程]