title: Performance, kinetics behaviors and microbial community of internal circulation anaerobic reactor treating wastewater with high organic loading rate: Role of external hydraulic circulation.
abstract: Performance of internal circulation anaerobic reactor (IC) treating wastewater at high organic loading rate (OLR) and role of external hydraulic circulation were evaluated. When the OLR was increased from 2.50 to 18.94kgCOD/m3/d, COD removal decreased to 85% slightly and methane production increased to 4.49L/L/d with the upflow velocity of 1.0m/h resulted from the additional hydraulic circulation. Withdrawal of external hydraulic circulation led to decrease of COD removal to lower than 60% drastically and methane production by 81%. Accumulation of volatile fatty acids caused decline of pH to below 6.0 and the shift of substrate metabolic pathway to the hybrid fermentation. In addition, both maximum methane production rate and maximum substrate degradation rate obtained from mathematical models decreased significantly. Hydrogenotrophic methanogens including Methanobacterium and Methanocorpusculum predominated in the anaerobic sludge and the shift of microbial community was also observed.
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
authors.forename: Gan
authors.initials: G
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China. Electronic address: liyan_0921@126.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
authors.forename: Wen-Tao
authors.initials: WT
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Li
mesh_terms: D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D059014:High-Throughput Nucleotide Sequencing; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008697:Methane / Q000378:metabolism; D017013:Methanobacteriaceae / Q000235:genetics / Q000378:metabolism; D059013:Microbial Consortia / Q000235:genetics / Q000502:physiology*; D008962:Models, Theoretical; D011422:Propionates / Q000378:metabolism; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods; D062065:Wastewater / Q000737:chemistry*
chemical_list: D005232:Fatty Acids, Volatile; D008697:Methane; D011422:Propionates; D012722:Sewage; D062065:Wastewater
keywords: High-throughput sequencing; Internal circulation anaerobic (IC) reactor; Kinetics behavior; Microbial community; Volatile fatty acids (VFA)