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Chinese Journal of Chemical Engineering 2023年第1期53卷 83-88页

作者： Chao Zhang Youzhi Liu Weizhou Jiao Hongyan Shen Xigang Yuan Shengkun Jia Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China State Key Laboratory for Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

In this study,an optimization method is proposed to enhance the gas–liquid mass transfer in bubble column reactor based on the entropy generation extremum *** mass transfer–induced entropy generation can be maximized with the increase of mass transfer rate,based on which the velocity field can be *** oxygen gas–liquid mass transfer is the major rate–limiting step of the toluene emissions biodegradation process in bubble column reactor,so the entropy generation due to oxygen mass transfer is used as the objective function,and the conservation equations of the gas–liquid flow and species concentration are taken as *** optimization problem is solved by the calculus of variations,the optimal liquid flow pattern is obtained and the relationship of the maximum mass transfer enhancement on viscous dissipation is revealed,which can be used to improve the design of internal structure of the bubble column reactor.

关键词： Entropy generation bubble column reactor Optimization Biodegradation Flow field

Modeling of mass transfer characteristics of bubble column reactor with surfactant present

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Journal of Zhejiang University Science 2004年第6期5卷 714-720页

作者：赵伟荣史惠祥汪大翚 DepartmentofEnvironmentalEngineering ZhejiangUniversityHangzhou310027China

Danckwert’s method was used to determine the specific interfacial area, a, and the individual mass transfer coefficient, kL, during absorption of CO2 in a bubble column with an anionic surfactant in the carbonate-bicarbonate buffer solution and NaAsO2 as catalyst, the presence of which decreases the specific interfacial area and the individual mass transfer coefficient. The specific interfacial area and the individual mass transfer coefficient increase with increasing su- perficial gas velocity. The specific interfacial area decreases whereas the individual mass transfer coefficient increases with increasing temperature. The results of experiments were used to determine the dependence of a, kL, and kLa on the surface tension, the temperature of the absorption phase, and the superficial velocity of the gas. The calculated results from the correlation were found to be within 10% deviation from the actual experimental results.

关键词： Mass transfer coefficient Surfactant bubble column reactor Gas absorption

Removal of SO2 using ammonium bicarbonate aqueous solution as absorbent in a bubble column reactor

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Frontiers of Chemical Science and Engineering 2013年第2期7卷 185-191页

作者： Xiaolei LI Chunying ZHU Youguang MA School of Chemical Engineering and Technology State Key Laboratory of Chemical Engineering Tianjin University Tianjin 300072 China

In this work, the removal of SO2 from gas mixture with air and SO2 by ammonium bicarbonate aqueous solution as absorbent was investigated experi- mentally in a bubble column reactor. The effects of the concentration of ammonium bicarbonate, the SO2 inlet concentration of gas phase and the gas flow rate on the removal rate of SO2 were studied. The results showed that the higher the SO2 inlet concentration and the gas flow rate, the shorter the lasting time of SO2 completely removed in gas outlet, and then the faster the decrease in the removal rate of SO2. The lasting time of SO2 completely removed in gas outlet increased with increasing ammonium bicarbonate concentration. During the process of SO2 absorption, there was a critical pH of solution. When the solution pH was less than the critical pH, it would sharply fall, resulting in a rapid decrease of the SO2 removal rate. A theoretical model for predicting the SO2 removal rate has been developed by taking the chemical enhancement and the sulfite concentration in the liquid phase into account simultaneously.

关键词： SO2 removal bubble column reactor removalrate ammonium bicarbonate absorbent

bubble column reactor Fluid-dynamic Evaluation at Pilot-plant for Residue and Extra-heavy Crude Oil Upgrading Technology

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Journal of Chemistry and Chemical Engineering 2015年第3期9卷 176-190页

作者： Ricardo Sardella Palma Zacarias Luis Paiva Miguel Medina Henry Infrastructure and Upgrading Department PDVSA-Intevep Los Teques-Miranda 1201 Venezuela Refining Department PDVSA-Intevep Los Teques-Miranda 1201 Venezuela

bubble column reactors are multiphase contacting devices used in a wide variety of industrial application. Inrtevep S. A. is working on developing technologies to convert heavy and extra-heavy crude oil using this type of reactors. Volumetric gas hold up, flow pattern, average gas bubble size, average interfacial area, RTD （residence time distribution）, dispersion coefficient, Peclet number are important design parameters for a proper scale up of them. Several cold model experiments have been proposed to determine the previously mentioned parameters at atmospheric conditions, using a plexiglas bubble column reactor at pilot plant scale unit （12 cm diameter）. It was also evaluated our own design of internal trays （plates） in the reactor. Air-tap water and air-light oil systems have been used. A wide operating condition range was applied, superficial gas velocity between 0.5-10 cm/s, liquid flowrate between 15-65 I/h. Generally speaking, working without internal trays was found that gas hold up increase along the reactor and it was possible to identify heterogeneous bubble, transition and turbulent flow pattern areas for the air-light oil system. Average gas bubble size increase along the reactor at bubble regime from 2-5 mm but at turbulent regime, stay oscillating between 1-3 mm. Average interfacial area increases exponentially with superficial gas velocity at any reactor height, till 1,412 m2/m3 for the air-light oil system but, at bubble flow regime, the average interfacial area is lower than 100 m2/m3, which negatively impact the reactor performance. Internal trays in the reactor always increase gas hold up at any condition or system used. Residence time distributions curves, Peclet numbers and dispersion coefficients founded, show that this reactor with this kind of design internal trays still tends to be a complete mixing reactor under the operating conditions used.

关键词： Fluid dynamic bubble column reactor residue upgrading technology trays.

Different efficiency toward the biomimetic aerobic oxidation of benzyl alcohol in microchannel and bubble column reactors: Hydrodynamic characteristics and gas–liquid mass transfer

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Chinese Journal of Chemical Engineering 2023年第3期55卷 84-92页

作者： Qi Han Xin-Yuan Zhang Hai-Bo Wu Xian-Tai Zhou Hong-Bing Ji Fine Chemical Industry Research Institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Sun Yat-sen UniversityHuizhou 516081China

The selective aerobic oxidation of benzyl alcohol to benzaldehyde has attracted considerable attention because benzaldehyde is a high value-added product. The rate of this typical gas–liquid reaction is significantly affected by mass transfer. In this study, CoTPP-mediated(CoTPP: cobalt(II) mesotetraphenylporphyrin) selective benzyl alcohol oxidation with oxygen was conducted in a membrane microchannel(MMC) reactor and a bubble column(BC) reactor, respectively. We observed that 83% benzyl alcohol was converted within 6.5 min in the MMC reactor, but only less than 10% benzyl alcohol was converted in the BC reactor. Hydrodynamic characteristics and gas–liquid mass transfer performances were compared for the MMC and BC reactors. The MMC reactor was assumed to be a plug flow reactor,and the dimensionless variance was 0.29. Compared to the BC reactor, the gas–liquid mass transfer was intensified significantly in MMC reactor. It could be ascribed to the high gas holdup(2.9 times higher than that of BC reactor), liquid film mass transfer coefficient(8.2 times higher than that of BC reactor), and mass transfer coefficient per unit interfacial area(3.8 times higher than that of BC reactor). Moreover,the Hatta number for the MMC reactor reached up to 0.61, which was about 15 times higher than that of the BC reactor. The computational fluid dynamics calculations for mass fractions in both liquid and gas phases were consistent with the experimental data.

关键词： Membrane microchannel reactor Gas-liquid flow Mass transfer Benzyl alcohol Computational fluid dynamics(CFD) bubble column reactor

Numerical Simulation of Unsteady-State Flowsin bubble column reactors

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Transactions of Tianjin University 2003年第4期9卷 283-288页

作者：张金利包佳琨李韡胡瑞杰韩振亭 School of Chemical Engineering and Technology

Unsteady-state operation has been widely applied in chemical engineering, such as optimizing a process, increasing yield and saving energy, etc. But the knowledge of the flow characteristics in bubble column reactors(BCRs) under unsteady state control is far from enough. In order to study the flow structures in this operation, the volume of fluid (VOF) model and the standard k-ε model to simulate the evolution of gas-liquid flow in BCRs under the start-up state are combined. For both the symmetry and asymmetry flow, the layout of the gas-inlets, the gas-in velocity, the liquid viscosity and the aspect ratio of the BCR all have effects on the liquid velocity distribution. The simulation results could provide some information for the design and scale-up of the BCRs.

关键词： bubble column reactor numerical simulation gas-liquid flow flow structure

Removal of dyes from wastewater by growing fungal pellets in a semi-continuous mode

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 338-345页

作者： Tao Lu Qilei Zhang Shanjing Yao Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China

To increase the efficiency of dye removal from wastewater using mycelial pellets, a bubble column reactor with a simple structure was designed and efficiently used to remove dyes from solution containing dyes. The mycelial pellets were prepared by marine fungus Aspergillus niger ZJUBE-1. Eight dyes were tested as dye targets for the adsorption capacity of mycelial pellets and good removal results were obtained. Eriochrome black T was selected as a model dye for characterizing the adsorption processes in detail. The measurement results of Zeta potential and FT- IR analysis indicate that the electrostatic attraction may play a key role in the biosorption process. The bubble column reactor was utilized to study the batch dye-removal efficiency of mycelial pellets. A re-culture process between every two batches, which was under non-sterile condition, successfully enhanced the utilization of mycelium bio- mass. The dye removal rate is 96.4% after 12 h in the first batch and then decreases slowly in the following batches. This semi-continuous mode, which consists of commutative processes of dye-removal and re-culture, has some outstanding advantages, such as low power consumption, easy operation, high dye removal rate, and efficient biomass utilization.

关键词： dye mycelial pellets marine fungus bubble column reactor semi-continuous biosorption