The characteristics of hydrogen and methane production from landfill leachate by anaerobic fermentation at 37 ℃ and pH 7. 0 was studied. The experimental results suggested that during the process of leachate anaerobic fermentation,the maximum cumulative production of hydrogen and methane was 24. 33,91. 95 mL (counted by per gram of COD) respectively; there was a lag phase a in the process of hydrogen production,while the methane production process appear no lag phase. Large amount of volatile organic acids and ethanol were found in the ultimate liquid product in hydrogen production process with the concentration of ethanol,acetate and butyrate was 487. 23,1 175. 21, 1 225. 78 mg/L respectively. Compared with hydrogen production process,ethanol,acetate and butyrate production of methane production process was relatively low,the concentration of was 256. 38,106. 73,107. 42 mg/L respectively. The ultimate mixture of hydrogen production process was strong acidic, the pH value was 4. 21. While, in methane production process,the ultimate mixture was close to neutral, the pH value was 6. 32. The removal rate of COD in methane production process was 41. 78% , which was higher than that of hydrogen production process (32. 14%). This might be the acetate in ultimate mixture of hydrogen production process could be utilized by methanogenesis and further be biodegrade.%以实际垃圾渗滤液作为厌氧发酵基质,研究了初始pH为7.0、中温(37℃)条件下的发酵产氢、产甲烷特性.结果表明,利用垃圾渗滤液作为基质发酵产氢或甲烷时,氢气的最大累积产量为24.33 mL(以每克COD计,下同),甲烷的最大累积产量为91.59 mL,产氢发酵在初期存在明显的迟滞期,但是产甲烷发酵不存在明显迟滞期；产氢发酵的液相末端产物中含有大量的挥发性有机酸和乙醇,乙醇、乙酸、丁酸质量浓度分别为487.23、1175.21、1225.78 mg/L,相比产氢发酵,产甲烷发酵的液相末端产物中乙醇、乙酸、丁酸质量浓度均较低,分别为256.38、106.73、107.42 mg/L；产甲烷发酵的最终pH是6.32,接近中性,而产氢发酵的最终pH为4.21,呈明显酸性；产甲烷发酵对COD的去除率(41.78％)高于产氢发酵对COD的去除率(32.14％),可能是产氢发酵液相末端产物中的乙酸能被产甲烷菌利用,而被进一步降解.
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