title: Fine-tuning key parameters of an integrated reactor system for the simultaneous removal of COD, sulfate and ammonium and elemental sulfur reclamation.
abstract: In this paper, we proposed an integrated reactor system for simultaneous removal of COD, sulfate and ammonium (integrated C-S-N removal system) and investigated the key parameters of the system for a high level of elemental sulfur (S(0)) production. The system consisted of 4 main units: sulfate reduction and organic carbon removal (SR-CR), autotrophic and heterotrophic denitrifying sulfide removal (A&H-DSR), sulfur reclamation (SR), and aerated filter for aerobic nitrification (AN). In the system, the effects of key operational parameters on production of elemental sulfur were investigated, including hydraulic retention time (HRT) of each unit, sulfide/nitrate (S(2-)-S/NO3(-)-N) ratios, reflux ratios between the A&H-DSR and AN units, and loading rates of chemical oxygen demand (COD), sulfate and ammonium. Physico-chemical characteristics of biosulfur were studied for acquiring efficient S(0) recovery. The experiments successfully explored the optimum parameters for each unit and demonstrated 98% COD, 98% sulfate and 78% nitrogen removal efficiency. The optimum HRTs for SR-CR, A&H-DSR and AN were 12h, 3h and 3h, respectively. The reflux ratio of 3 could provide adequate S(2-)-S/NO3(-)-N ratio (approximately 1:1) to the A&H-DSR unit for obtaining maximum sulfur production. In this system, the maximum production of S(0) reached 90%, but only 60% S(0) was reclaimed from effluent. The S(0) that adhered to the outer layer of granules was deposited in the bottom of the A&H-DSR unit. Finally, the microbial community structure of the corresponding unit at different operational stage were analyzed by 16S rRNA gene based high throughput Illumina MiSeq sequencing and the potential function of dominant species were discussed.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: yuanye_19840915@163.com.
authors.forename: Ye
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: echo110244@126.com.
authors.forename: Chuan
authors.initials: C
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: liangbin1214@163.com.
authors.forename: Bin
authors.initials: B
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: hengyue5257@163.com.
authors.forename: Cong
authors.initials: C
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: zhaoyoukang@gmail.com.
authors.forename: Youkang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: xuxijun3220@sina.com.
authors.forename: Xijun
authors.initials: X
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: tanwenbo1@163.com.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Tan
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: x.zhou@awmc.uq.edu.au.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: localinna.1990@163.com.
authors.forename: Shuang
authors.initials: S
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: sundezhi@bjfu.edu.cn.
authors.forename: Dezhi
authors.initials: D
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan. Electronic address: djlee@ntu.edu.tw.
authors.forename: Duujong
authors.initials: D
authors.lastname: Lee
authors.affiliation: Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK 73019, USA; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. Electronic address: jzhou@ou.edu.
authors.forename: Jizhong
authors.initials: J
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: waj0578@hit.edu.cn.
authors.forename: Aijie
authors.initials: A
authors.lastname: Wang
mesh_terms: D000465:Algorithms; D064751:Ammonium Compounds / Q000302:isolation & purification*; D001419:Bacteria / Q000737:chemistry / Q000378:metabolism; D019149:Bioreactors; D002244:Carbon / Q000737:chemistry; D002852:Chromatography, Ion Exchange; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D013431:Sulfates / Q000302:isolation & purification*; D013455:Sulfur / Q000737:chemistry / Q000302:isolation & purification*; D016999:Sulfur-Reducing Bacteria / Q000378:metabolism*; D062065:Wastewater / Q000737:chemistry; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D064751:Ammonium Compounds; D002244:Carbon; D009584:Nitrogen; D010100:Oxygen; D013431:Sulfates; D013455:Sulfur; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Aerated nitrification; Denitrifying sulfide removal; Elemental sulfur production; Sulfate reduction and organic carbon removal; Sulfur reclamation