title: Enhancement of the dewaterability of sludge during bioleaching mainly controlled by microbial quantity change and the decrease of slime extracellular polymeric substances content.
abstract: Contribution rates of factors controlling sludge dewaterability during bioleaching, such as sludge pH, microbial quantity, extracellular polymeric substances (EPS), etc., were investigated in this study. Results showed that the dewaterability of bioleached sludge was jointly enhanced by the growth of Acidithiobacillus sp., the increase of Fe(3+) concentration, the decreases of sludge pH, heterotrophic microorganism quantity change, and the decreases of EPS and bound water contents. Ridge regression analysis further revealed that the contribution rates of microbial quantity change, bound water content and slime EPS content on sludge dewaterability enhancement were 32.50%, 24.24%, and 22.37%, respectively, all of which are dominant factors. Therefore, the enhancement of sludge dewaterability was mainly controlled by microbial quantity change and the decrease of bound water and slime EPS contents during bioleaching.
authors.affiliation: Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Minbo
authors.initials: M
authors.lastname: Huo
authors.affiliation: Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing 210095, China.
authors.forename: Guanyu
authors.initials: G
authors.lastname: Zheng
authors.affiliation: Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: lxzhou@njau.edu.cn.
authors.forename: Lixiang
authors.initials: L
authors.lastname: Zhou
mesh_terms: D042763:Acidithiobacillus / Q000254:growth & development / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001704:Biopolymers / Q000032:analysis*; D005591:Chemical Fractionation; D002681:China; D015169:Colony Count, Microbial; D005110:Extracellular Space / Q000737:chemistry*; D052836:Heterotrophic Processes; D006863:Hydrogen-Ion Concentration; D012044:Regression Analysis; D012722:Sewage / Q000737:chemistry*; D013997:Time Factors; D014867:Water / Q000737:chemistry*
chemical_list: D001704:Biopolymers; D012722:Sewage; D014867:Water
keywords: Bioleaching; Dewaterability; Extracellular polymeric substances; Microbial quantity; Municipal sewage sludge