{"title":"Mixing Effect on Bio-Methanation, Settleability and Dewaterability in the Anaerobic Digestion of Sewage Sludge Fractions","authors":"D. Erdirencelebi, R. Yi̇ği̇t","doi":"10.35208/ert.1243907","DOIUrl":null,"url":null,"abstract":"Biomethanation and dewaterability characteristics of primary (PS), secondary sludge (SS) and mixed sludge (MS) fractions were assessed after anaerobic stabilization under parallel batch and continuous mixing conditions at 35℃ in order to investigate the performance of the separate digestion system. Similar methane conversion/yield values were obtained in PS, SS and MS digestion with continuous mixing’s positive effect only in PS digestionContinuous mixing resulted in 50% increase in the methane yield (600(+/-100) mL/g VSadd.d. SS sludge digestion produced a comparable methane yield at 650(+/-100) mL/g VSadd.d showing no effect due to mixing pattern. Settling and dewaterability characteristics of the stabilized PS were superior to stabilized SS samples. A reverse relationship was obtained between settling characteristics and where intermittent mixing enhanced settling ability while continuous mixing resulted in higher dewaterability of the stabilized sludges. PE addition showed a negative effect on the settleability of the sludges. Low degree mixing resulted in lower Imhoff settling volume with 50% sludge volume reduction and an SVI of 64 mL/g VS compared to 25% volume reduction and 82 mL/g SVI in the CM mode for the stabilized PS. A similar trend for the stabilized SS but worsened values with 25% volume reduction and an SVI 182 mL/g compared to 15% volume reduction and 200 mL/g VS indicated much lower settleability character in the CM mode and compared to stabilized PS.","PeriodicalId":126818,"journal":{"name":"Environmental Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Research and Technology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.35208/ert.1243907","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Biomethanation and dewaterability characteristics of primary (PS), secondary sludge (SS) and mixed sludge (MS) fractions were assessed after anaerobic stabilization under parallel batch and continuous mixing conditions at 35℃ in order to investigate the performance of the separate digestion system. Similar methane conversion/yield values were obtained in PS, SS and MS digestion with continuous mixing’s positive effect only in PS digestionContinuous mixing resulted in 50% increase in the methane yield (600(+/-100) mL/g VSadd.d. SS sludge digestion produced a comparable methane yield at 650(+/-100) mL/g VSadd.d showing no effect due to mixing pattern. Settling and dewaterability characteristics of the stabilized PS were superior to stabilized SS samples. A reverse relationship was obtained between settling characteristics and where intermittent mixing enhanced settling ability while continuous mixing resulted in higher dewaterability of the stabilized sludges. PE addition showed a negative effect on the settleability of the sludges. Low degree mixing resulted in lower Imhoff settling volume with 50% sludge volume reduction and an SVI of 64 mL/g VS compared to 25% volume reduction and 82 mL/g SVI in the CM mode for the stabilized PS. A similar trend for the stabilized SS but worsened values with 25% volume reduction and an SVI 182 mL/g compared to 15% volume reduction and 200 mL/g VS indicated much lower settleability character in the CM mode and compared to stabilized PS.