title: Comparison of biodiesel production from sewage sludge obtained from the A²/O and MBR processes by in situ transesterification.
abstract: The potential of two types of sludge obtained from the anaerobic-anoxic-oxic (A(2)/O) and membrane bioreactor (MBR) processes as lipid feedstock for biodiesel production via in situ transesterification was investigated. Experiments were conducted to determine the optimum conditions for biodiesel yield using three-factor and four-level orthogonal and single-factor tests. Several factors, namely, methanol-to-sludge mass ratio, acid concentration, and temperature, were examined. The optimum yield of biodiesel (16.6% with a fatty acid methyl ester purity of 96.7%) from A(2)/O sludge was obtained at a methanol-to-sludge mass ratio of 10:1, a temperature of 60°C, and a H2SO4 concentration of 5% (v/v). Meanwhile, the optimum yield of biodiesel (4.2% with a fatty acid methyl ester purity of 92.7%) from MBR sludge was obtained at a methanol-to-sludge mass ratio of 8:1, a temperature of 50°C, and a H2SO4 concentration of 5% (v/v). In this research, A(2)/O technology with a primary sedimentation tank is more favorable for obtaining energy from wastewater than MBR technology.
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors: Juanjuan
authors: J
authors: Qi
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China. Electronic address: zhufenfen@ruc.edu.cn.
authors: Fenfen
authors: F
authors: Zhu
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors: Xiang
authors: X
authors: Wei
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors: Luyao
authors: L
authors: Zhao
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors: Yiqun
authors: Y
authors: Xiong
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors: Xuemin
authors: X
authors: Wu
authors: School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China.
authors: Fawei
authors: F
authors: Yan
mesh_terms: D056804:Biofuels / Q000032:analysis*; D019149:Bioreactors; D002849:Chromatography, Gas; D004951:Esterification; D006358:Hot Temperature; D013058:Mass Spectrometry; D012722:Sewage / Q000032:analysis / Q000737:chemistry*; D018505:Waste Management / Q000379:methods*
chemical_list: D056804:Biofuels; D012722:Sewage
keywords: Biodiesel; In situ transesterification; Sewage sludge