title: Multivariate analysis of sludge disintegration by microwave-hydrogen peroxide pretreatment process.
abstract: Microwave irradiation (with H2O2) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2-20 g/L), pH (4-10), and H2O2 dosage (0-2 w/w) and their interactions on 16 response variables (e.g., SCODreleased, pH, H2O2remaining). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSSremaining, and H2O2 remaining). Quadratic predictive models were constructed for all 16 response variables (R(2): 0.871-0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H2O2 and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China.
authors.forename: Wang
authors.initials: W
authors.lastname: Ya-Wei
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China.
authors.forename: Gui
authors.initials: G
authors.lastname: Cheng-Min
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China.
authors.forename: Ni
authors.initials: N
authors.lastname: Xiao-Tang
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China.
authors.forename: Chen
authors.initials: C
authors.lastname: Mei-Xue
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China. Electronic address: Yswei@rcees.ac.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Yuan-Song
mesh_terms: D057919:Biological Oxygen Demand Analysis; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008872:Microwaves; D008956:Models, Chemical; D015999:Multivariate Analysis; D012722:Sewage / Q000032:analysis*; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D012722:Sewage; D006861:Hydrogen Peroxide
keywords: Hydrogen peroxide; Microwave; Response surface methodology (RSM); Sludge disintegration