title: Polyhydroxyalkanoates in waste activated sludge enhances anaerobic methane production through improving biochemical methane potential instead of hydrolysis rate.
abstract: Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d(-1)) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.
authors.affiliation: School of Automation Science &Engineering, South China University of Technology, Guangdong 510640, China.|Advanced Water Management Centre (AWMC), The University of Queensland, QLD 4072, Australia.
authors.forename: Qilin
authors.initials: Q
authors.lastname: Wang
authors.affiliation: School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.|Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Advanced Water Management Centre (AWMC), The University of Queensland, QLD 4072, Australia.
authors.forename: Guo-Jun
authors.initials: GJ
authors.lastname: Xie
authors.affiliation: Advanced Water Management Centre (AWMC), The University of Queensland, QLD 4072, Australia.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhou
authors.affiliation: School of Natural and Applied Sciences, Northwestern Polytechnical University, Xi'an 710129, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Qian
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.|Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Guojing
authors.initials: G
authors.lastname: Yang
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.|Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
authors.affiliation: School of Automation Science &Engineering, South China University of Technology, Guangdong 510640, China.
authors.forename: Yiqi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Advanced Water Management Centre (AWMC), The University of Queensland, QLD 4072, Australia.|College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.|Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Dongbo
authors.initials: D
authors.lastname: Wang
mesh_terms: D000693:Anaerobiosis; D006868:Hydrolysis; D008697:Methane / Q000096:biosynthesis* / Q000737:chemistry*; D054813:Polyhydroxyalkanoates / Q000737:chemistry; D012722:Sewage
chemical_list: D054813:Polyhydroxyalkanoates; D012722:Sewage; D008697:Methane