环境工程专业英语

环境工程专业英语第一页，共十三页，2022年，8月28日Abstract：Ananaerobichydrogenfermentationsystemwithathermophilicflow-throughreactor(55oC)forhydrogenproductionandaboilingretentionvessel(100oC)forcontinuousheattreatment,wasstudiedforenhancedcontinuoushydrogenfermentationusingsewagesludge.TheperformanceofthehydrogenfermentationsystemwastestedatvariousHydraulicRetentionTimes(HRTs)rangedfrom1to5days.Theheattreatmentofthefermentingsludgeusingtheboilingretentionvesselwasaneffectivetoselecthydrogenproducingbacteria,andtoincreasethehydrolysisofparticulateorganicsinsewagesludge。

第二页，共十三页，2022年，8月28日Introduction

Commercialhydrogenisalmostproducedfromsteamreformingofnaturalgasesandgasificationofcoal,buttheserequirehigh-energyinputsobtainedfromnon-renewableresources.Withbothadvantagesofhydrogenproductionandstabilizationoforganicwaste,theanaerobicfermentationisrelativelyanefficientandinexpensivemethodcomparedtothephysicochemicalmethodsforhydrogenproduction.Theobjectiveofthestudyistodevelopacontinuousanaerobichydrogenfermentationsystemwithstablehydrogenproductionbyheattreatment,andwithhighyieldofhydrogenbyadoptingthermophiliccondition.

第三页，共十三页，2022年，8月28日MaterialsandMethods

ExperimentalApparatus

GassamplingpotActivatingreactorBiogasSludgetankInsutationHeatingCoilThermophilicfermenterEfluent第四页，共十三页，2022年，8月28日AnalysisandCalculations

Biogasproductionwasmonitoreddaily,anditscompositionwasanalyzedbyagaschromatographequippedwithathermalconductivitydetectorToanalyzethemethaneandcarbondioxideinthebiogas.withaflowrateof40mL/min,andthetemperaturesoftheinjector,detector,andcolumnwere80,90,and50oC,respectively.Thevolatilefattyacidlevelsandtheircompositionswereanalyzedbyhigh-performanceliquidchromatography.Themixedliquorswereintermittentlytaken

fromboththeflow-throughandtheretentionreactor,andthe

properties,includingpH,alkalinity,COD,VSS,VS,andTS,of

thesampleswerealsoanalyzedaccordingtotheStandard

Methods.ThehydrolysisrateandVFAproductionratewerecalculatedbyEqs.(1)and(2)respectively.

[(massSCOD/d)effluent−(massSCOD/d)influent]/

[(massPCOD/d)influent−(massPCOD/d)effluent](1)

[(massVFA/d)effluen−(massVFA/d)influent]/

[(massSCOD/d)effluen−(massSCOD/d)influent](2)

第五页，共十三页，2022年，8月28日HydrogenProduction

HydrolysisandVSReduction

VFAProductionandHydrogenYield

ResultsandDiscussion第六页，共十三页，2022年，8月28日HydrogenProduction

第七页，共十三页，2022年，8月28日

HydrogenProduction第八页，共十三页，2022年，8月28日

HydrogenProduction

thehydrogenproductionratewasquicklyincreasedandapproachedtosteadystatewithinthe10thdayoftheoperationat1dayHRT

theexposureofthefermentingsludgetoheatisagoodapproachforboththeselectionofhydrogenproductionbacteriaandtheenhancementofhydrolysisrateofparticulateorganicmatter.However,aproperHRTisalsoveryimportanttoobtainhigherhydrogenproduction.Inthestudy,theproperHRTwas3days,andthehydrogenproductionwaslimitedbythehydrolysisratefor1dayHRTandbythehydrogenconsumptionactivityfor5daysHRT.

第九页，共十三页，2022年，8月28日HydrolysisandVSReduction

Thehydrolysisintheanaerobicdegradationfororganicsludgecontainingparticulatematterisusuallyaratelimitingstep,affectingonthewholeperformanceofanaerobicprocess,anddeterminingVS(VolatileSolids)removalofthesludge.VSremovalandhydrolysisrateweresignificantlyaffectedbypHconditionInthecaseofRunIIIwith5daysHRT,VSremovalwas37.9%,whichwashigherthanRunIorRunII.TheeffectoftheexposuretimeofthefermentingsludgetoheatwasconfirmedagainbytheincreaseofVSremovalinRunIIIwithlongerHRT.

第十页，共十三页，2022年，8月28日HRTintheanaerobichydrogenfermentationsystemwithcontinuousheattreatmentisanimportantparameterinselectinghydrogenproducingbacteriaanddeterminingthepathwaysforminghydrogen.pHisanotherimportantparameterdeterminingthemetabolicpathwayforminghydrogen

VFAProductionandHydrogenYield第十一页，共十三页，2022年，8月28日highermaximumyieldofhydrogencomparedtopreviousstudieswas3.07mmolH2/gTS,whichwasobtainedat3daysHRT.ThehydrogenyieldandhydrolysisrateweresignificantlyaffectedbypHcondition,andproperpHforthehydrogenfermentationwasfrom5.5to6.5.Thehydrogenproductionwaslimitedbythehydrolysisfor1dayHRTandbythehydrogenconsumptionactivityfor5daysHRT

第十二页，共十三页，2022年，8月28日Conclusion

Thecontinuoushydrogenfermentationsystem,consistedofa

thermophilic(55℃)flowthroughreactorandaboilingretention

vessel(100℃)forcontinuousheattreatmentwasagoodprocess

forcontinuoushydrogenproductionfromsewagesludge.The

continuousheattreatmentofthefermentingsludgeusingthe

boilingretentionvesselwasaneffectivemethodfortheselection

ofhydrogenproducingbacteria,andtheincreaseofVSremoval

invirtueoftheenhancementofhydrolysisforparticulateorganics

insewagesludge.Theperformanceofhydrogenfermentation

wassignificantlyaffectedbythehydraulicretentiontimeand

pH,andtheoptimalconditi