title: Bacterial communities and their association with the bio-drying of sewage sludge.
abstract: Bio-drying is a technology that aims to remove water from a material using the microbial heat originating from organic matter degradation. However, the evolution of bacterial communities that are associated with the drying process has not been researched systematically. This study was performed to investigate the variations of bacterial communities and the relationships among bacterial communities, water evaporation, water generation, and organic matter degradation during the bio-drying of sewage sludge. High-throughput pyrosequencing was used to analyze the bacterial communities, while water evaporation and water generation were determined based on an in situ water vapor monitoring device. The values of water evaporation, water generation, and volatile solids degradation were 412.9 g kg(-1) sewage sludge bio-drying material (SSBM), 65.0 g kg(-1) SSBM, and 70.2 g kg(-1) SSBM, respectively. Rarefaction curves and diversity indices showed that bacterial diversity plummeted after the temperature of the bio-drying pile dramatically increased on d 2, which coincided with a remarkable increase of water evaporation on d 2. Bacterial diversity increased when the pile cooled. During the thermophilic phase, in which Acinetobacter and Bacillus were the dominant genera, the rates of water evaporation, water generation, and VS degradation peaked. These results implied that the elevated temperature reshaped the bacterial communities, which played a key role in water evaporation, and the high temperature also contributed to the effective elimination of pathogens.
authors.affiliation: Faculty of Architectural, Civil Engineering and Environment, Ningbo University, Ningbo, China; Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China. Electronic address: cailu@nbu.edu.cn.
authors.forename: Lu
authors.initials: L
authors.lastname: Cai
authors.affiliation: Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China. Electronic address: chentb@igsnrr.ac.cn.
authors.forename: Tong-Bin
authors.initials: TB
authors.lastname: Chen
authors.affiliation: Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China. Electronic address: gaod@igsnrr.ac.cn.
authors.forename: Ding
authors.initials: D
authors.lastname: Gao
authors.affiliation: Faculty of Architectural, Civil Engineering and Environment, Ningbo University, Ningbo, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yu
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics; D018407:Bacterial Physiological Phenomena; D004269:DNA, Bacterial / Q000235:genetics; D003890:Desiccation / Q000379:methods*; D009930:Organic Chemicals / Q000378:metabolism; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology*; D013696:Temperature; D014835:Volatilization; D014867:Water / Q000737:chemistry*
chemical_list: D004269:DNA, Bacterial; D009930:Organic Chemicals; D012722:Sewage; D014867:Water
keywords: Bacterial communities; Bio-drying; Degradation; Sewage sludge; Water evaporation; Water generation