A novel modified expanded granular sludge bed(EGSBm) reactor was developed for anaerobic treatment of municipal sewage with mixed liquid recirculation instead of effluent recirculation commonly adopted by a convention...A novel modified expanded granular sludge bed(EGSBm) reactor was developed for anaerobic treatment of municipal sewage with mixed liquid recirculation instead of effluent recirculation commonly adopted by a conventional EGSB(EGSBc) reactor.Performances of these two reactors were compared in treating municipal sewage at ambient temperatures ranging from 8 to 26 ℃.At an upflow liquid velocity(Vup) of 10.3 m/h,the mean concentrations of filtrated COD(CODfilt) and COD of the EGSBm effluent were determined to be 59.4 and 95.9 mg/L,respectively,which were significantly lower than those of the EGSBc effluent operated under identical experimental conditions.When the organic loading rate was suddenly increased from 1.2 to 7.2 kg COD/(m3·d),the EGSBm regained the removal efficiency of previous operation phase in 10 d.Hydrodynamic characteristics of the reactors were compared using the residence time distribution(RTD) model.It was found that the treatment efficiency of EGSBm kept increasing as the Vup increased.The polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis(PCR-DGGE) technique was used to analyze the microbial diversity in EGSBm.Fingerprinting pattern indicated that some species in the inoculating sludge were still reserved in the granular sludge of EGSBm,moreover,several new species occurred.展开更多
The quality of shallow groundwater in the West Lake watershed wasinvestigated form March to July 2000. Integrating with BlacklandGRASS GIS system, the DRASTIC model was used to compile the ground-water vulnerability m...The quality of shallow groundwater in the West Lake watershed wasinvestigated form March to July 2000. Integrating with BlacklandGRASS GIS system, the DRASTIC model was used to compile the ground-water vulnerability map. A land use factor was added to the DRASTICmodel and the modified model (LDRASTIC0 increased the accuracy ofprediction form 26.9/100 to 51.3/100. The vulnerability map showedthat the lowly, moderately and highly susceptible area predictedoccupied about 11.6/100, 70.9/100 and 17.5/100 of the wholewatershed, respectively. Compared with the observed values of nitrateand electric conductivity, the LDRASTIC index improved the Pearsoncorrelation coefficients form -0.010 to 0.237 and 0.380 to 0.503;Both the improved coefficients were significant at the 0.01 level.The modified DRASTIC analysis showed a Great potential as a screeningtool for policy decision-making in groundwater management.展开更多
The objective of this studying was to accurate determination of Biological Oxygen Demand (BOD) through the use of two types of prepared inoculums, the natural activated sludge supplied from conventional wastewater t...The objective of this studying was to accurate determination of Biological Oxygen Demand (BOD) through the use of two types of prepared inoculums, the natural activated sludge supplied from conventional wastewater treatment plant and the modified activated sludge prepared from activated sludge of wastewater treatment plant of refinery factory. Analytical method was used to measurement of BOD by preparing the standard curve of BOD in basal medium. The results showed to the large differences in BOD values in basal medium (30-300 mg/L) and conventional wastewater (80-320 mg/L) when they were inoculated with natural and modified activated sludge respectively. It was also found an ability of modified sludge to remove high concentrations of oil and greases.展开更多
[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide (CATB) modified attapulgite was used to modi...[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide (CATB) modified attapulgite was used to modify attapulgite, and conducted dynamic test on micro-polluted phenol wastewater. The dynamic charac- teristics of phenol removal were also studied. [Result] Attapulgite modified by CATB has strong adsorption ability on phenol in micro-polluted water, the phenol removal rate increased with the decrease of flow rate of wastewater. When pH value was 6- 8, phenol concentration in wastewater was 17.74 mg/L, flow rate was 2 m/s and ad- sorption time was 25 rain, the removal rate reached 93.07%. The modified atta- pulgite could be regenerated with alkali, and its adsorption ability after regeneration had no obvious decline. The dynamic adsorption process of phenol accorded with the first-order kinetic equation. [Conclusion] The study provided basis for further study on "organic matter removal in wastewater.展开更多
Graphene oxide(GO) has been demonstrated to be an effective hydrophilic nanofiller to modify the polymeric membranes when forming a mixed matrix structure. GO quantum dots(QDs) are promising candidates to fully exert ...Graphene oxide(GO) has been demonstrated to be an effective hydrophilic nanofiller to modify the polymeric membranes when forming a mixed matrix structure. GO quantum dots(QDs) are promising candidates to fully exert the rich oxygen containing functional groups due to their unique size induced edge effects. In this work, GO QDs modified polysulfone(PSF) ultrafiltration(UF) membranes were prepared by phase inversion method with various GO QDs loadings(0.1–0.5 wt.%). A proper amount of GO QDs addition led to a more porous and hydrophilic membrane structure. With 0.3 wt.% GO QDs, the membranes showed a60% increase in permeability(130.54 vs. 82.52 LMH bar^-1).The pristine PSF membranes had a complete cutoff of bovine serum albumin molecules and it was well maintained with GO QDs incorporated. The membranes with 0.5 wt.% GO QDs exhibited the highest flux recovery ratio of 89.7% and the lowest irreversible fouling of 10.3%(54.5% and 33.3% for the pristine PSF membranes). Our results proved that GO QDs can function as effective nanofillers to enhance the hydrophilicity, permeability and antifouling performance of PSF UF membranes.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.20876117)National Key Technologies Research & Development Program(Grant No.2006BAJ08B10,2006BAJ04A07,2008BAJ08B21)
文摘A novel modified expanded granular sludge bed(EGSBm) reactor was developed for anaerobic treatment of municipal sewage with mixed liquid recirculation instead of effluent recirculation commonly adopted by a conventional EGSB(EGSBc) reactor.Performances of these two reactors were compared in treating municipal sewage at ambient temperatures ranging from 8 to 26 ℃.At an upflow liquid velocity(Vup) of 10.3 m/h,the mean concentrations of filtrated COD(CODfilt) and COD of the EGSBm effluent were determined to be 59.4 and 95.9 mg/L,respectively,which were significantly lower than those of the EGSBc effluent operated under identical experimental conditions.When the organic loading rate was suddenly increased from 1.2 to 7.2 kg COD/(m3·d),the EGSBm regained the removal efficiency of previous operation phase in 10 d.Hydrodynamic characteristics of the reactors were compared using the residence time distribution(RTD) model.It was found that the treatment efficiency of EGSBm kept increasing as the Vup increased.The polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis(PCR-DGGE) technique was used to analyze the microbial diversity in EGSBm.Fingerprinting pattern indicated that some species in the inoculating sludge were still reserved in the granular sludge of EGSBm,moreover,several new species occurred.
基金Project supported by the British Council (No. SHA/992/297) and the Zhejiang Provincial Science and Technology Development Found
文摘The quality of shallow groundwater in the West Lake watershed wasinvestigated form March to July 2000. Integrating with BlacklandGRASS GIS system, the DRASTIC model was used to compile the ground-water vulnerability map. A land use factor was added to the DRASTICmodel and the modified model (LDRASTIC0 increased the accuracy ofprediction form 26.9/100 to 51.3/100. The vulnerability map showedthat the lowly, moderately and highly susceptible area predictedoccupied about 11.6/100, 70.9/100 and 17.5/100 of the wholewatershed, respectively. Compared with the observed values of nitrateand electric conductivity, the LDRASTIC index improved the Pearsoncorrelation coefficients form -0.010 to 0.237 and 0.380 to 0.503;Both the improved coefficients were significant at the 0.01 level.The modified DRASTIC analysis showed a Great potential as a screeningtool for policy decision-making in groundwater management.
文摘The objective of this studying was to accurate determination of Biological Oxygen Demand (BOD) through the use of two types of prepared inoculums, the natural activated sludge supplied from conventional wastewater treatment plant and the modified activated sludge prepared from activated sludge of wastewater treatment plant of refinery factory. Analytical method was used to measurement of BOD by preparing the standard curve of BOD in basal medium. The results showed to the large differences in BOD values in basal medium (30-300 mg/L) and conventional wastewater (80-320 mg/L) when they were inoculated with natural and modified activated sludge respectively. It was also found an ability of modified sludge to remove high concentrations of oil and greases.
基金Supported by Innovation Fund Project of Ministry of Science and Technology(10C26213201183)~~
文摘[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide (CATB) modified attapulgite was used to modify attapulgite, and conducted dynamic test on micro-polluted phenol wastewater. The dynamic charac- teristics of phenol removal were also studied. [Result] Attapulgite modified by CATB has strong adsorption ability on phenol in micro-polluted water, the phenol removal rate increased with the decrease of flow rate of wastewater. When pH value was 6- 8, phenol concentration in wastewater was 17.74 mg/L, flow rate was 2 m/s and ad- sorption time was 25 rain, the removal rate reached 93.07%. The modified atta- pulgite could be regenerated with alkali, and its adsorption ability after regeneration had no obvious decline. The dynamic adsorption process of phenol accorded with the first-order kinetic equation. [Conclusion] The study provided basis for further study on "organic matter removal in wastewater.
基金supported by Beijing Natural Science Foundation(2172027)
文摘Graphene oxide(GO) has been demonstrated to be an effective hydrophilic nanofiller to modify the polymeric membranes when forming a mixed matrix structure. GO quantum dots(QDs) are promising candidates to fully exert the rich oxygen containing functional groups due to their unique size induced edge effects. In this work, GO QDs modified polysulfone(PSF) ultrafiltration(UF) membranes were prepared by phase inversion method with various GO QDs loadings(0.1–0.5 wt.%). A proper amount of GO QDs addition led to a more porous and hydrophilic membrane structure. With 0.3 wt.% GO QDs, the membranes showed a60% increase in permeability(130.54 vs. 82.52 LMH bar^-1).The pristine PSF membranes had a complete cutoff of bovine serum albumin molecules and it was well maintained with GO QDs incorporated. The membranes with 0.5 wt.% GO QDs exhibited the highest flux recovery ratio of 89.7% and the lowest irreversible fouling of 10.3%(54.5% and 33.3% for the pristine PSF membranes). Our results proved that GO QDs can function as effective nanofillers to enhance the hydrophilicity, permeability and antifouling performance of PSF UF membranes.