摘要
将污水接种活性污泥后在厌氧、中温(37℃)和120 r/min条件下进行批培养,添加浓度为1.0 g/l柠檬酸钠时的产气量和产沼气对所消耗的葡萄糖的得率系数分别比对照提高38.5%和61.9%;但是糖平均消耗速率和最终pH值分别比对照下降了12.5%和7.1%。厌氧培养过程中的挥发性脂肪酸(VFA)变化趋势差异明显,对照VFA浓度在24 h达到最大值,此时其浓度是添加柠檬酸钠组VFA浓度的82%,之后逐渐降低。但是,添加组VFA含量随着培养的进行逐渐增大,VFA的平均积累速率和VFA对葡萄糖的得率系数分别比对照增加了232%和279%。柠檬酸钠的添加促进了葡萄糖向VFA的代谢合成,为甲烷合成提供了充足的底物,提高了葡萄糖转化甲烷的效率和沼气总量。
The effects of citrate on methane production during the treatment of organic wastewater were investigated in batch assays at 37℃ and 120 rpm. The results showed that the methane fermen- tation was stimulated. At a sodium citrate concentration of 1.0 g/L, the methane production and biogas yield in glucose consumed increased by 38.5% and 61.9%, respectively. However, the glucose con- sumption rate and the final pH value were 12.5% and 7.1% lower than those of the contrasted one, re- spectively. Further more,change of volatile fatty acids （VFA） during the course of anaerobic batch fermentation was obvious between citrate addition sample and the contrasted one. The maximal VFA concentration of the contrasted one reached at 24 h,which was 82% of that of the citrate addition sample , and then reduced gradually. However, the VFA content of the citrate addition sample in- creased along with cultivation process,and the VFA production rate and VFA yield in glucose con- sumption increased by 232% and 279% o The results suggest that citrate regulated the carbon flux to the synthesis of VFA, which facilitated the precursor supply of methane synthesis, and then en- hanced the efficiency of glucose utilization for methane and biogas production.
出处
《可再生能源》
CAS
北大核心
2009年第1期69-72,共4页
Renewable Energy Resources
基金
武汉市科学技术局攻关项目(200820212029)
湖北省教育厅重点项目(D20081401)
关键词
厌氧发酵
沼气
代谢
anaerobic batch cultivation
biogas
metabolism
