An expanded granular sludge bed (EGSB) reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granu...An expanded granular sludge bed (EGSB) reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granular sludge during the start-up period being investigated. The results indicated that the EGSB reactor can be started up successfully in 27 d by increasing the organic loading rate rapidly. The removal efficiency of COD was maintained above 93% with influent COD concentration of 25 000 mg/L and OLR of 37.94 kgCOD/(m 3 ·d). The EGSB reactor with good pH self-balancing could be fed with fresh leachate of low pH value (4 5). The biogas production rate was closely related with OLR and COD reduction. Every gram of COD fed (consumed) to the reactor produced 0.34 L STP (0.36 L STP ) biogas with 0.21 L STP (0.23 L STP ) methane. Thus, 65% 70% of the produced biogas was methane. Sixty one percentage of COD fed to the reactor was converted to methane, another 33% was converted to biomass by metabolism, and the other 6% was left in the liquid phase. The specific methanogenic activity (SMA) of the granular sludge had increased by 92% after 27 d dynamic incubation. The granular sludge in the reactor had good settlement performance with majority diameter of 1 2 mm.展开更多
A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extract...A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which correspond...展开更多
A periodic packing mode of trickle-bed reactor (TBR) for the gas limited reaction was proposed. Hy-drogenation of 2-ethylanthraquinone over Pd/Al2O3 in a laboratory-scale TBR was taken as a test reaction for determini...A periodic packing mode of trickle-bed reactor (TBR) for the gas limited reaction was proposed. Hy-drogenation of 2-ethylanthraquinone over Pd/Al2O3 in a laboratory-scale TBR was taken as a test reaction for determining whether the periodic packing mode is advantageous. The effects of operating conditions and packing type on TBR performance were experimentally examined to demonstrate the cause-effect relationships. A mathe-matic model of TBR considering axial dispersion and fractional wetting was developed to quantitatively illuminate the reason of performance enhancement.展开更多
Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amou...Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amount of modifier, initial concentration of reactant, pressure and temperature on conversion and enantiometric excess in a stirred autoclave and the effects of the liquid velocity, gas velocity, modifier concentration and various catalytic beds in a trickle-bed reactor. The maximum optical yields were about 50% and 60% in the two types of reactors, respectively. It was assumed that the total hydrogenation rate included the reaction rates over the unmodified and modified active sites on platinum surface and a kinetic model, which fitted the experimental data well in autoclave, was obtained. A simplified plug-flow model was proposed to describe the bed average efficiency of trickle-bed reactor.展开更多
基金supported by the Science and Technology Commission of Shanghai Municipality (Grant Nos.10DZ120010C,D9DZ2251700)
文摘An expanded granular sludge bed (EGSB) reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granular sludge during the start-up period being investigated. The results indicated that the EGSB reactor can be started up successfully in 27 d by increasing the organic loading rate rapidly. The removal efficiency of COD was maintained above 93% with influent COD concentration of 25 000 mg/L and OLR of 37.94 kgCOD/(m 3 ·d). The EGSB reactor with good pH self-balancing could be fed with fresh leachate of low pH value (4 5). The biogas production rate was closely related with OLR and COD reduction. Every gram of COD fed (consumed) to the reactor produced 0.34 L STP (0.36 L STP ) biogas with 0.21 L STP (0.23 L STP ) methane. Thus, 65% 70% of the produced biogas was methane. Sixty one percentage of COD fed to the reactor was converted to methane, another 33% was converted to biomass by metabolism, and the other 6% was left in the liquid phase. The specific methanogenic activity (SMA) of the granular sludge had increased by 92% after 27 d dynamic incubation. The granular sludge in the reactor had good settlement performance with majority diameter of 1 2 mm.
基金the National NaturalScience Foundation (No. 30570053)the Fund of CrossSubjects of Zhejiang University (No. 109000-812651)+2 种基金the National Natural Science Foundation of China (No.50406022)the National High Technology Research and Development Program of China (No. 2007AA10Z409)the National Key Project of Scientific and Technical Supporting Programs Funded by Ministry of Science &Technology of China (No. 2006BAJ08B01)
文摘A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which correspond...
基金the State Key Development Program for Basic Research of China (No. G2000048005) the SINOPEC (No.X503023).
文摘A periodic packing mode of trickle-bed reactor (TBR) for the gas limited reaction was proposed. Hy-drogenation of 2-ethylanthraquinone over Pd/Al2O3 in a laboratory-scale TBR was taken as a test reaction for determining whether the periodic packing mode is advantageous. The effects of operating conditions and packing type on TBR performance were experimentally examined to demonstrate the cause-effect relationships. A mathe-matic model of TBR considering axial dispersion and fractional wetting was developed to quantitatively illuminate the reason of performance enhancement.
文摘Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amount of modifier, initial concentration of reactant, pressure and temperature on conversion and enantiometric excess in a stirred autoclave and the effects of the liquid velocity, gas velocity, modifier concentration and various catalytic beds in a trickle-bed reactor. The maximum optical yields were about 50% and 60% in the two types of reactors, respectively. It was assumed that the total hydrogenation rate included the reaction rates over the unmodified and modified active sites on platinum surface and a kinetic model, which fitted the experimental data well in autoclave, was obtained. A simplified plug-flow model was proposed to describe the bed average efficiency of trickle-bed reactor.