Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production:effect of pH at ambient temperature  

作　　者：Leiyu FENG Yuanyuan YAN Yinguang CHEN 

机构地区：[1]State Key Laboratory of Pollution Control and Resources Reuse,School of Environmental Science and Engineering,Tongji University,Shanghai 200092,China

出　　处：《Frontiers of Environmental Science & Engineering》2011年第4期623-632,共10页环境科学与工程前沿（英文）

基　　金：This work was financially supported by the Foundation of State Key Laboratory of Pollution Control and Resources Reuse(Tongji University)(Nos.PCRRK09002 and PCRRY10001);China Postdoctoral Science Foundation(Nos.20100470730 and 20100480622);Tianjin Key Laboratory of Aquatic Science and Technology(Nos.TJKLAST-2011-03 and TJKLAST-2011-04)。

摘　　要：Effect of pH ranging from 4.0 to 11.0 on cofermentation of waste activated sludge(WAS)with food waste for short-chain fatty acids(SCFAs)production at ambient temperature was investigated in this study.Experimental results showed that the addition of food waste significantly improved the performance of WAS fermentation system,which resulted in the increases of SCFAs production and substrate reduction.The SCFAs production at pH 6.0,7.0,8.0,and 9.0 and fermentation time of 4 d was respectively 5022.7,6540.5,8236.6,and 7911.7 mg COD·L^(-1),whereas in the blank tests(no pH adjustment,pH 8.0(blank test 1),no food waste addition,pH 8.0(blank test 2),and no WAS addition(blank test 3))it was only 1006.9,971.1,and 1468.5 mg COD·L^(-1),respectively.The composition of SCFAs at pH from 6.0 to 9.0 was also different from other conditions and propionic acid was the most prevalent SCFA,which was followed by acetic and n-butyric acids,while acetic acid was the top product under other conditions.At pH 8.0 a higher volatile suspended solids(VSS)reduction of 16.6%for the mixture of WAS and food waste than the sole WAS indicated a synergistic effect existing in fermentation system with WAS and food waste.The influence of pH on the variations of nutrient content was also studied during anaerobic fermentation of the mixture of WAS and food waste at different pH conditions.The release of NH_(4)^(+)-N increased with fermentation time at all pH values investigated except 4.0,5.0 and in blank test one.The concentrations of soluble phosphorus at acidic pHs and in the blank test one were higher than those obtained at alkaline pHs.Ammonia and phosphorus need to be removed before the SCFAsenriched fermentation liquid from WAS and food waste was used as the carbon source.

关 键 词：waste activated sludge(WAS) food waste COFERMENTATION short-chain fatty acids(SCFAs) PH synergistic effect 

分 类 号：X70[环境科学与工程—环境工程]