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Measurement of Concentration Fields near the Interface of a Rising Bubble by Holographic Interference Technique

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Chinese Journal of Chemical Engineering 1999年第4期7卷 363-367页

作者：马友光成弘 YuGuocong 余国琮 chemicalengineeringresearchcenter TianjinUniversityTianjin300072China

holographic interference, concentration near the interface, bubble , mass transfer

关键词： holographic interference concentration near the interface bubble mass transfer

Turbulent Liquid Flow in a Gas-Liquid Bubble Column

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Chinese Journal of Chemical Engineering 1999年第3期7卷 189-195页

作者：王树立张敏卿范敏英余国琮 chemicalengineeringresearchcenter TianjinUniversityTianjin300072China DepartmentofMechanicalEngineering PashunPetroleumInstituteFushun113001China

The radial distribution of the axial component of time-average liquid velocity and turbulent intensity in a gas-liquid bubble column was investigated experimentally using Laser Doppler Anemometer (LDA). The effects of operating parameters on liquid turbulent intensity are studied and an empirical relationship between turbulent intensity and viscosity was established. Such a relationship can be used conveniently in the calculation of liquid velocity profiles in bubble columns.

关键词： bubble column liquid velocity field turbulent intensity turbulent viscosity

HYDRAULIC ENERGY RECOVERY FOR SWRO DESALINATION PLANTS

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化工学报 2003年第6期54卷 878-879页

作者：王越王世昌徐世昌 chemicalengineeringresearchcenter SchoolofChemicalEngineeringandTechnology StateKeyLaboratoryofChemicalEngineering TianjinUniversity

Since the 1980s, turbine type energy recovery devices have been used in Sea Water Reverse Osmosis (SWRO) desalination plants in a dominant position. In recent years, positive displacement (PD) energy recovery devices (such as types PX and PES) have been developed rapidly and tend to replace turbines because of their higher efficiency~[1,2]. Their efficiency is reported to be above 90%, while the efficiency of turbines is only about 30%-50%~[3].

关键词：水能 SWRO 海水反渗透性能量回收脱盐作用脱盐车间

Preparation of 6-APA by Enzymatic Bioconversion in an Emulsion Liquid Membrane Reactor

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Chinese Journal of Chemical Engineering 2001年第4期9卷 431-435页

作者：陆强胡鸣熊丹柳邓修 UnilabResearchCenterofChemicalReactionEngineering EastChinaUniversityofScienceandTechnologyShanghai200237China chemicalengineeringresearchcenter EastChinaUniversityofScienceandTechnologyShanghai200237China

Production of 6-aminopenicillanic acid (6-APA) by hydrolysis using penicillin acylase (PA) was studied as a model of an enzymatic emulsion liquid membrane (ELM) process. The loss of PA activity was examined for various membrane compositions (organic solvent, surfactant, carrier). The effects of some experimental variables on the stability of emulsion were investigated. It was found that the choice of organic solvent greatly affected the stability of the emulsion. Increasing the concentration of the carrier in the membrane phase increases the transfer rate of substrate and products but also has a destabilizing effect on the emulsion. The recovery of 6-APA obtained by a di-carrier system (N263-N1923) was much higher than those when either of the di-carriers was used separately. The whole process was controlled both by the enzymatic reaction rate and by the transfer rate of the substrate and the products, however, the ratio of them could be changed by varying the composition of the system. For an optimum condition, it was obtained that the recovery ratio of 6-APA was over 80% and the conversion of benzyl penicillin (PG) was up to 90% in the external phase after 30 minutes. Meanwhile, the breakage percentage of the emulsion was less than 2%.

关键词： 6-aminopenicillanic acid penicillin enzymatic bioconversion emulsion liquid membrane reactor

Population dynamics and spa-tial distribution of microbial species in multispecies biofilms under the action of direct electric current

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Chinese Science Bulletin 2003年第24期48卷 2688-2693页

作者： CAOHongbin LIXingang WUJinchuan ZHONGFangli ZHANGYi chemicalengineeringresearchcenter SchoolofChemicalEngineering&TechnologyTianjinUniversityTianjin300072China InstituteofProcessEngineering ChineseAcademyofSciencesBeijing100080China

The metabolism, population dynamics and spa-tial distribution of nitrifying bacteria and heterotrophs in biofilms under the action of direct electric current were in-vestigated by using the micro-slicing technique. The nitrifi-cation rate of nitrifying bacteria was severely inhibited by a current over 10 Am-2 at lower C/N ratios. Compared to het-erotrophs, the nitrifying bacteria in the surface biofilms were severely inhibited, resulting in a significant decrease in bac-terial density. An increase in current density narrowed the less current-sensitive inner biofilm region, and in addition the density of NO2-oxidizers decreased more significantly than that of NH4-oxidizers in the surface biofilms probably due to electrochemical reactions at the anode. However, the effect of current on both the population dynamics and the spatial distribution of the microbial species was less signifi-cant at larger C/N ratios.

关键词：空间分布人口动力学微生物生物薄膜硝化作用大气污染污染治理

Measurement and Prediction of Interfacial Area on a DistiIlation Tray

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Transactions of Tianjin University 2003年第1期9卷 29-34页

作者：宋海华李天一李红海 chemicalengineeringresearchcenter TianjinUniversity

In this paper the modern electron optical equipment is used to translate the clear image of speed moving bubbles in bubbling liquid on a sieve tray into the digital information stored in computer, and the computer aided image processing technique is utilized to measure the bubble size distributions and interfacial areas under various operating conditions. And the dynamic behavior of bubbles in turbulent liquid is analyzed theoretically; the mechanism of bubble deformation and breakage is explored on the basis of Kolmogoroff′s isotropic turbulence hypothesis; the mathematical model for predicting the gas liquid interfacial area is proposed. The comparison between the simulated results and the experimental data shows that the model is higher in accuracy, simple in form and convenient in use.

关键词： bubble size distribution interfacial area multiphase turbulent dynamics computer aided image analysis distillation tray

Network Structure Expert System and Operation Optimization

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Transactions of Tianjin University 2003年第1期9卷 35-40页

作者：刘洪谦袁希钢麻德贤 chemicalengineeringresearchcenter TianjinUniversity SchoolofChemicalEngineering BeijingUniversityofChemicalEngineering

It is proposed that double level programming technique may be adopted in synthesis strategy. Optimization of heat exchanger network structural configuration (the master problem) may be solved at the upper level, leaving the rest operating conditions( the slave problem) being optimized at the lower level. With the uniqueness in mind, an HEN synthesis expert system may be employed to address both the logical constraints and the global operation parameters′ optimization using enhanced sequential number optimization *** studies demonstrate that the synthesis strategy proposed can effectively simplify both the problem solving and the synthesis process. The validity of the strategy recommended is evidenced by case studies′ results compared.

关键词： heat exchanger networks(HEN) sequential number theoretic optimization (SNTO) expert system