title: Characteristics of extracellular polymeric substances and bacterial communities in an anaerobic membrane bioreactor coupled with online ultrasound equipment.
abstract: Two parallel anaerobic membrane bioreactors (MBRs), integrated with or without ultrasound equipment for online membrane fouling control (US-AnMBR, or AnMBR) were established to digest waste activated sludge (WAS). The characteristics of bound extracellular polymeric substances (EPS) and bacterial communities in the systems were investigated for further understanding of the membrane fouling mechanisms. Ultrasound was an effective method for reducing cake layer resistance. A relatively high amount of bound EPS were found in the cake layer, especially for the US-AnMBR, by responding to the external forces (i.e. cross flow and ultrasound). High-throughput pyrosequencing and denaturing gradient gel electrophoresis (DGGE) were applied to analyze the bacterial diversity. Some bacterial populations contributing to membrane fouling were identified to accumulate in the cake layer, such as Peptococcaceae, Bacteroides and Syntrophobacterales. Since the ultrasounded retentate was recirculated back to the reactor, the bacterial community in the digested sludge was affected.
authors.affiliation: Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Yu
authors.forename: Xianghua
authors.initials: X
authors.lastname: Wen
authors.forename: Meilan
authors.initials: M
authors.lastname: Xu
authors.forename: Xia
authors.initials: X
authors.lastname: Huang
mesh_terms: D000693:Anaerobiosis; D001419:Bacteria / Q000254:growth & development*; D001704:Biopolymers / Q000737:chemistry*; D019149:Bioreactors / Q000382:microbiology*; D005110:Extracellular Space / Q000737:chemistry*; D008567:Membranes, Artificial; D009862:Online Systems / Q000295:instrumentation; D014465:Ultrasonics / Q000295:instrumentation*; D018508:Water Purification / Q000295:instrumentation*
chemical_list: D001704:Biopolymers; D008567:Membranes, Artificial