title: Effects of toxic organic flotation reagent (aniline aerofloat) on an A/O submerged membrane bioreactor (sMBR): Microbial community dynamics and performance.
abstract: Bio-treatment of flotation wastewater has been proven to be both effective and economical, as a treatment method. Despite this, little is known regarding the effects of toxic organic floatation reagents such as Dianilinodithiophosphoric acid (DDA), on the microbial community performance or dynamics, which are critical to the effective performance of the bio-treatment reactor. A submerged membrane bioreactor (sMBR) was constructed to continuously treat simulated wastewater contaminated with DDA, an organic flotation reagent that is now considered a significant pollutant. The performance of the sMBR system was investigated at different DDA loading concentrations, with assessment of the effects of DDA on the microbial communities within the sMBR, in particular the biodiversity and succession within the microbial community. Results showed that, with increased DDA loadings, the performance of the sMBR was initially negatively affected, but the system adapted efficiently and consistently reached a COD removal rate of up to 80%. Increased DDA loading concentrations had an adverse effect on the activity of both the activated sludge and microbial communities, resulting in a large alteration in microbial dynamics, especially during the start-up stage and the high DDA loading stage. Strains capable of adapting to the presence of DDA, capable of degrading DDA or utilizing its byproducts, were enriched within the sMBR community, such as Zoogloea, Clostridium, Sideroxydans lithotrophicus, Thiobacillus, Thauera amino aromatica and Alicycliphilus denitrificans.
authors.affiliation: Guangdong Polytechnic of Environmental Protection Engineering，Foshan 528216, China; School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
authors.forename: Weixiong
authors.initials: W
authors.lastname: Lin
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Polytechnic of Environmental Protection Engineering，Foshan 528216, China. Electronic address: sysun@gdut.edu.cn.
authors.forename: Shuiyu
authors.initials: S
authors.lastname: Sun
authors.affiliation: Guangdong Polytechnic of Environmental Protection Engineering，Foshan 528216, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Wu
authors.affiliation: Guangdong Polytechnic of Environmental Protection Engineering，Foshan 528216, China.
authors.forename: Pingting
authors.initials: P
authors.lastname: Xu
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
authors.forename: Ziwei
authors.initials: Z
authors.lastname: Ye
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
authors.forename: Shengwei
authors.initials: S
authors.lastname: Zhuang
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry / Q000633:toxicity*; D044822:Biodiversity; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D008567:Membranes, Artificial; D059013:Microbial Consortia / Q000187:drug effects*; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000382:microbiology; D018508:Water Purification / Q000379:methods*
chemical_list: D000814:Aniline Compounds; D008567:Membranes, Artificial; D012722:Sewage; D062065:Wastewater
keywords: Dominant microbial species; Floatation wastewater; Microbial community dynamics; Submerged membrane bioreactor (sMBR); Toxic organic floatation reagent