环境工程专业英语优秀PPT.ppt

环境工程专业英语你现在浏览的是第一页，共13页 An An anaerobic anaerobic hydrogen hydrogen fermentation fermentation system system with with a a thermophilic thermophilic flow-flow-through through reactor reactor(55(55o oC)C)for for hydrogen hydrogen production production and and a a boiling boiling retention retention vessel vessel(100(100o oC)C)for for continuous continuous heat heat treatment,treatment,was was studied studied for for enhanced enhanced continuous continuous hydrogen hydrogen fermentation fermentation using using sewage sewage sludge.sludge.The The performance performance of of the the hydrogen hydrogen fermentation fermentation system system was was tested tested at at various various Hydraulic Hydraulic Retention Retention Times Times(HRTs)(HRTs)ranged ranged from from 1 1 to to 5 5 days.days.The The heat heat treatment treatment of of the the fermenting fermenting sludge sludge using using the the boiling boiling retention retention vessel vessel was was an an effective effective to to select select hydrogen hydrogen producing producing bacteria,bacteria,and and to to increase increase the the hydrolysis hydrolysis of of particulate particulate organics organics in in sewage sewage sludgesludge。你现在浏览的是第二页，共13页 Commercial hydrogen is almost produced from steam reforming of natural Commercial hydrogen is almost produced from steam reforming of natural gases and gasification of coal,but these require high-energy inputs obtained gases and gasification of coal,but these require high-energy inputs obtained from non-renewable resources.With both advantages of hydrogen production from non-renewable resources.With both advantages of hydrogen production and stabilization of organic waste,the anaerobic fermentation is relatively an and stabilization of organic waste,the anaerobic fermentation is relatively an efficient and inexpensive method compared to the physicochemical methods efficient and inexpensive method compared to the physicochemical methods for hydrogen production.The objective of the study is to develop a continuous for hydrogen production.The objective of the study is to develop a continuous anaerobic hydrogen fermentation system with stable hydrogen production by anaerobic hydrogen fermentation system with stable hydrogen production by heat treatment,and with high yield of hydrogen by adopting thermophilic heat treatment,and with high yield of hydrogen by adopting thermophilic condition.condition.你现在浏览的是第三页，共13页Experimental ApparatusGas sampling potActivating reactorBiogasSludge tankInsutationHeating CoilThermophilic fermenterEfluent你现在浏览的是第四页，共13页 Biogas production was monitored daily,and its composition was Biogas production was monitored daily,and its composition wasanalyzed by a gas chromatograph equipped with a thermal conductivity analyzed by a gas chromatograph equipped with a thermal conductivity detector To analyze the methane and carbon dioxide in the biogas.with a detector To analyze the methane and carbon dioxide in the biogas.with a flow rate of 40 mL/min,and the temperatures of theinjector,detector,and flow rate of 40 mL/min,and the temperatures of theinjector,detector,and column were 80,90,and 50column were 80,90,and 50o oC,respectively.The volatile fatty acid levels and C,respectively.The volatile fatty acid levels and their compositions were analyzed by high-performance liquid chromatography their compositions were analyzed by high-performance liquid chromatography.The mixed liquors were intermittently taken.The mixed liquors were intermittently takenfrom both the flow-through and the retention reactor,and thefrom both the flow-through and the retention reactor,and theproperties,including pH,alkalinity,COD,VSS,VS,and TS,ofproperties,including pH,alkalinity,COD,VSS,VS,and TS,ofthe samples were also analyzed according to the Standardthe samples were also analyzed according to the StandardMethods.The hydrolysis rate and VFA productionrate were calculated by Eqs.(1)Methods.The hydrolysis rate and VFA productionrate were calculated by Eqs.(1)and(2)respectively.and(2)respectively.(massSCOD/d)effluent(massSCOD/d)influent/(massSCOD/d)effluent(massSCOD/d)influent/(massPCOD/d)influent(massPCOD/d)effluent(1)(massPCOD/d)influent(massPCOD/d)effluent(1)(massVFA/d)effluen(massVFA/d)influent/(massVFA/d)effluen(massVFA/d)influent/(massSCOD/d)effluen(massSCOD/d)influent(2)(massSCOD/d)effluen(massSCOD/d)influent(2)你现在浏览的是第五页，共13页Hydrogen ProductionHydrogen ProductionHydrolysis and VS ReductionHydrolysis and VS ReductionVFA Production and Hydrogen YieldVFA Production and Hydrogen YieldResults and Discussion你现在浏览的是第六页，共13页你现在浏览的是第七页，共13页Hydrogen ProductionHydrogen Production你现在浏览的是第八页，共13页 Hydrogen ProductionHydrogen Production the hydrogen production rate was quickly increased and the hydrogen production rate was quickly increased and approached to steady state within the 10th day of the operation approached to steady state within the 10th day of the operation at 1 day HRT at 1 day HRT the exposure of the fermenting sludge to heat is a good approach for the exposure of the fermenting sludge to heat is a good approach for both the selection of hydrogen production bacteria and the enhancement both the selection of hydrogen production bacteria and the enhancement of hydrolysis rate of particulate organic matter.However,a proper HRT is of hydrolysis rate of particulate organic matter.However,a proper HRT is also very important to obtain higher hydrogen production.In the study,also very important to obtain higher hydrogen production.In the study,the proper HRT was 3 days,and the hydrogen production was limited by the proper HRT was 3 days,and the hydrogen production was limited by the hydrolysis rate for 1day HRT and by the hydrogen consumption the hydrolysis rate for 1day HRT and by the hydrogen consumption activity for 5 days HRT.activity for 5 days HRT.你现在浏览的是第九页，共13页Hydrolysis and VS ReductionHydrolysis and VS Reduction The hydrolysis in the anaerobic degradation for organic sludge containing The hydrolysis in the anaerobic degradation for organic sludge containing particulate matter is usually a rate limiting step,affecting on the whole performance particulate matter is usually a rate limiting step,affecting on the whole performance of anaerobic process,and determining VS(Volatile Solids)removal of the sludge.of anaerobic process,and determining VS(Volatile Solids)removal of the sludge.VS removal and hydrolysis rate were significantly affected by pH VS removal and hydrolysis rate were significantly affected by pH conditionIn the case of Run III with 5days HRT,VS removal was 37.9%,conditionIn the case of Run III with 5days HRT,VS removal was 37.9%,which was higher than Run I or Run II.The effect of the exposure time of which was higher than Run I or Run II.The effect of the exposure time of the fermenting sludge to heatwas confirmed again by the increase of VS the fermenting sludge to heatwas confirmed again by the increase of VS removal in Run IIIwith longer HRT.removal in Run IIIwith longer HRT.你现在浏览的是第十页，共13页 HRT in the anaerobic hydrogen fermentation system with continuous heat HRT in the anaerobic hydrogen fermentation system with continuous heat treatment is an important parameter in selecting hydrogen producing bacteria treatment is an important parameter in selecting hydrogen producing bacteria and determining the pathways forming hydrogen.pH is another important and determining the pathways forming hydrogen.pH is another important parameter determining the metabolic pathway forming hydrogenparameter determining the metabolic pathway forming hydrogenVFA Production and Hydrogen YieldVFA Production and Hydrogen Yield你现在浏览的是第十一页，共13页 higher maximum yield of hydrogen compared to previous studies higher maximum yield of hydrogen compared to previous studies was 3.07 mmol H2/g TS,which was obtained at 3 days HRT.The was 3.07 mmol H2/g TS,which was obtained at 3 days HRT.The hydrogen yield and hydrolysis rate were significantly affected by pH hydrogen yield and hydrolysis rate were significantly affected by pH condition,and proper pH for the hydrogen fermentation was from 5.5 condition,and proper pH for the hydrogen fermentation was from 5.5 to 6.5.The hydrogen production was limited by the hydrolysis for to 6.5.The hydrogen production was limited by the hydrolysis for 1day HRT and by the hydrogen consumption activity for 5days HRT1day HRT and by the hydrogen consumption activity for 5days HRT你现在浏览的是第十二页，共13页 The continuous hydrogen fermentation system,consisted of a The continuous hydrogen fermentation system,consisted of athermophilic(55thermophilic(55)flow through reactor and a boiling retention)flow through reactor and a boiling retentionvessel(100vessel(100)for continuous heat treatment was a good process)for continuous heat treatment was a good processfor continuous hydrogen production from sewage sludge.Thefor continuous hydrogen production from sewage sludge.Thecontinuous heat treatment of the fermenting sludge using thecontinuous heat treatment of the fermenting sludge using theboiling retention vessel was an effective method for the selectionboiling retention vessel was an effective method for the selectionof hydrogen producing bacteria,and the increase of VS removalof hydrogen producing bacteria,and the increase of VS removalin virtue of the enhancement of hydrolysis for particulate organicsin virtue of the enhancement of hydrolysis for particulate organicsin sewage sludge.The performance of hydrogen fermentationin sewage sludge.The performance of hydrogen fermentationwas significantly affected by the hydraulic retention time andwas significantly affected by the hydraulic retention time andpH,and the optimal conditions were the HRT of 3days and pHpH,and the optimal conditions were the HRT of 3days and pH5.5-6.5,respectively.VS removal was increased according to5.5-6.5,respectively.VS removal was increased according toHRT and the maximum value was 37.9%at 5days of HRT.TheHRT and the maximum value was 37.9%at 5days of HRT.Themaximum hydrogen yield of the continuous hydrogen fermentationmaximum hydrogen yield of the continuous hydrogen fermentationsystem was 3.07 mmol H2 g TS-1 at 3 days of HRTsystem was 3.07 mmol H2 g TS-1 at 3 days of HRT你现在浏览的是第十三页，共13页