Gas-liquid microreaction technology has shown great potential in a variety of industrial relevant mass transfer operations and reactions. This paper outlines the current research status of this technology with emphasi...Gas-liquid microreaction technology has shown great potential in a variety of industrial relevant mass transfer operations and reactions. This paper outlines the current research status of this technology with emphasis on reactor design, hydrodynamics and mass transfer phenomena as well as reaction applications. The future challenges of this important technology are also summarized.展开更多
Microreaction technology is one of the most innovative and rapid developing fields in chemical engineering, synthesis and process technology. Many expectations toward enhanced product selectivity, yield and purity, im...Microreaction technology is one of the most innovative and rapid developing fields in chemical engineering, synthesis and process technology. Many expectations toward enhanced product selectivity, yield and purity, improved safety, and access to new products and processes are directed to the microreaction technology. Microfluidic mixer is the most important component in microfluidic devices. Based on various principles, active and passive micromixers have been designed and investigated. This review is focused on the recent developments in microfluidic mixers. An overview of the flow phenomena and mixing characteristics in active and passive micromixers is presented, including the types of physical phenomena and their utilization in micromixers. Due to the simple fabrication technology and the easy implementation in a complex microfluidic system, T-micromixer is highlighted as an example to illustrate the effect of design and operating parameters on mixing efficiency and fuid flow inside microfluidic mixers.展开更多
Using the multiple reference frames （MRF） impeller method, the three-dimensional non-Newtonian flow field generated by a double helical ribbon （DHR） impeller has been simulated. The velocity field calculated by th...Using the multiple reference frames （MRF） impeller method, the three-dimensional non-Newtonian flow field generated by a double helical ribbon （DHR） impeller has been simulated. The velocity field calculated by the numerical simulation was similar to the previous studies and the power constant agreed well with the experimental data. Three computational fluid dynamic （CFD） methods, labeled Ⅰ, Ⅱ and Ⅲ, were used to compute the Metzuer constant k5. The results showed that the calculated value from the slop method （method Ⅰ） was consistent with the experimental data. Method Ⅱ, which took the maximal circumference-average shear rate around the impeller as the effective shear rate to compute ks, also showed good agreement with the experiment. However, both methods suffer from the complexity of calculation procedures. A new method （method Ⅲ） was devised in this paper to use the area-weighted average viscosity around the impeller as the effective viscosity for calculating k5. Method Ⅲ showed both good accuracy and ease of use.展开更多
Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studi...Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems.展开更多
Steady-state non-dominated sorting genetic algorithm (SNSGA), a new form of multi-objective genetic algorithm, is implemented by combining the steady-state idea in steady-state genetic algorithms (SSGA) and the fitnes...Steady-state non-dominated sorting genetic algorithm (SNSGA), a new form of multi-objective genetic algorithm, is implemented by combining the steady-state idea in steady-state genetic algorithms (SSGA) and the fitness assignment strategy of non-dominated sorting genetic algorithm (NSGA). The fitness assignment strategy is improved and a new self-adjustment scheme of is proposed. This algorithm is proved to be very efficient both computationally and in terms of the quality of the Pareto fronts produced with five test problems including GA difficult problem and GA deceptive one. Finally, SNSGA is introduced to solve multi-objective mixed integer linear programming (MILP) and mixed integer non-linear programming (MINLP) problems in process synthesis.展开更多
This study aimed to identify and to analyze characteristics of top-cited articles published in the Web of Science chemical engineering subject category from 1899 to 2011.Articles that have been cited more than 100 tim...This study aimed to identify and to analyze characteristics of top-cited articles published in the Web of Science chemical engineering subject category from 1899 to 2011.Articles that have been cited more than 100 times were assessed regarding publication outputs,and distribution of outputs in journals.Five bibliometric indicators were used to evaluate source countries,institution and authors.A new indicator,Y-index,was created to assess quantity and quality of contribution to articles.Results showed that 3828 articles,published between 1931 and 2010,had been cited at least 100 times.Among them 54% published before 1991,and 49% top-cited articles originated from US.The top eight productive institutions were all located in US.The top journals were Journal of Catalysis,AIChE Journal,Chemical Engineering Science and Journal of Membrane Science.Y-index was successfully applied to evaluate publication character of authors,institutions,and countries/regions.展开更多
A method for incorporation of controlling the heat exchanger networks with or without splits is proposed by integrating mathemati-cal programming and knowledge engineering. The simultaneous optimal mathematical model ...A method for incorporation of controlling the heat exchanger networks with or without splits is proposed by integrating mathemati-cal programming and knowledge engineering. The simultaneous optimal mathematical model is established. This method can be practically used in the integration of large-scale heat exchanger networks, not only to synthesize automatically but also to satisfy the requirement of struc-tural controllability with more objective human intervention.展开更多
Behavior of catalytic cracking reactions of particle cluster in fluid catalytic cracking （FCC） riser reactors was numerically analyzed using a four-lump mathematical model. Effects of the cluster porosity, inlet gas...Behavior of catalytic cracking reactions of particle cluster in fluid catalytic cracking （FCC） riser reactors was numerically analyzed using a four-lump mathematical model. Effects of the cluster porosity, inlet gas velocity and temperature, and coke deposition on cracking reactions of the cluster were investigated. Distributions of temperature, gases, and gasoline from both catalyst particle cluster and an isolated catalyst particle are presented. The reaction rates from vacuum gas oil （VGO） to gasoline, gas and coke of individual particle in the cluster are higher than those of the isolated particle, but it reverses for the reaction rates from gasoline to gas and coke. Less gasoline is produced by particle clustering. Simulated results show that the produced mass fluxes of gas and gasoline increase with the operating temperature and molar concentration of VGO, and decrease due to the formation of coke.展开更多
The local gas-phase flow characteristics such as local gas holdup(εg), local bubble velocity (V_b) and local bubble mean diameter(d_b) at a specified point in a gas-liquid-solid three-phase reversedflow jet loop reac...The local gas-phase flow characteristics such as local gas holdup(εg), local bubble velocity (V_b) and local bubble mean diameter(d_b) at a specified point in a gas-liquid-solid three-phase reversedflow jet loop reactor was experimentally investigated by a five-pointconductivity probe. The effects of gas jet flow rate, liquid jet flowrate, solid loading, nozzle diameter and axial position on the localεg, V_b and d_b profiles were discussed. The presence of solids atlow solid concentrations not only increased the local εg and V_b,but also decreased the local d_b. The optimum solid loading for themaximum local εg and V_b together with the minimum local d_b was0.16×10^-3 m^3, corresponding to a solid volume fraction ε_S＝2.5/100.展开更多
Erosion-corrosion of liquid-solid two-phase flow occurring in a pipe with sudden expansion in cross-section is numerically simulated in this paper. The global model for erosion-corrosion process includes three main co...Erosion-corrosion of liquid-solid two-phase flow occurring in a pipe with sudden expansion in cross-section is numerically simulated in this paper. The global model for erosion-corrosion process includes three main components: the liquid-solid two-phase flow model, erosion model and corrosion model. The Eulerian-Lagrangian approach is used to simulate liquid-solid two-phase flow, while the stochastic trajectory model was adopted to obtain properties of particle phase. Two-way coupling effect between the fluid and the particle phase is considered in the model. The accuracy of the models is tested by the data in the reference. The comparison shows that the model is basically correct and feasible.展开更多
Introduced the application and development status of coal gasification tech- nology in China. The most widely used coal gasification technology in China is the at- mospheric fixed-bed gasifier, its total number is abo...Introduced the application and development status of coal gasification tech- nology in China. The most widely used coal gasification technology in China is the at- mospheric fixed-bed gasifier, its total number is about 9 000. About 30 pressurized fixed-bed gasifiers are in operation, and more than 10 atmospheric fluidized-bed gasifi- ers were used. There are 13 Texaco entrained-flow bed gasifiers are under operation, 10 Texaco and 11 Shell gasifiers that are being installed or imported. About 10 under- ground gasifiers are under running now. The present R&D of coal gasification technolo- gies are to improve the operation and controlling level of fixed-bed gasification technol- ogy, and developing or demonstration of fluidized-bed and entrained-flow bed gasifiers.展开更多
In recent decades,colleagues working in the Discipline of Geological Resources and Geological Engineering at Central South University made significant progress in theoretic study and application of geophysics,ore depo...In recent decades,colleagues working in the Discipline of Geological Resources and Geological Engineering at Central South University made significant progress in theoretic study and application of geophysics,ore deposit and shale gas geology,3 D predictive modeling of concealed resources,and geological engineering.In geophysics,world-class progress was achieved in the development,data processing,equipment,and scientific survey of electromagnetic method in onshore and offshore environments and the tectonic evolution of the Tibetan Plateau.Especially,advanced wide-field electromagnetic exploration method and equipment as a highlight technique won the first prize of National Science and Technology Invention of China.In ore geology,progressive and complex characteristics of most nonferrous ore deposits and the geodynamic relationship between crust-mantle reaction and mineralization in south China were revealed.Progressive metallogenic models of certain typical ore deposits were established based on the study of fluid inclusion and geochemistry.According to characteristics of complex metallogenic system of polygenetic ore deposit,key ore-controlling factors were found and summarized.The investigation on unconventional resources advanced China’s shale gas resource evaluation system.In 3 D predictive modelling of metallogenic,a large-scale location prediction model was established for exploration of crisis mines and concealed ore deposits.Our developed 3 D predictive modeling techniques for concealed orebodies were widely used to explore deep mineral resources in China.In geological engineering area,the key technologies for deep drilling into complex formations were developed.Especially the drilling fluid and tools were utilized in the fieldwork.The rock and soil mechanics analysis method and anchor technologies were also established and applied to engineering practice.展开更多
A new superstructure form of heat exchanger networks (HEN) isproposed based on expert system system (ES). The new superstructureform is combined with the practical engineering. The differentinvestment cost formula for...A new superstructure form of heat exchanger networks (HEN) isproposed based on expert system system (ES). The new superstructureform is combined with the practical engineering. The differentinvestment cost formula for Different heat exchanger is alsopresented based on ES. The mathematical model for the simultaneousoptimization Of network configuration is established and solved by agenetic algorithm. This method can deal with larger scale HENsynthesis and the optimal HEN configuration is obtainedautomatically. Finally, a case study is presented to Demonstrate theeffectiveness of the method.展开更多
基金Supported by the National Natural Science Foundation of China （20490208, 20676129）, the National High Technology Research and Development Program of China （2006AA05Z233, 2007AA030206）.
文摘Gas-liquid microreaction technology has shown great potential in a variety of industrial relevant mass transfer operations and reactions. This paper outlines the current research status of this technology with emphasis on reactor design, hydrodynamics and mass transfer phenomena as well as reaction applications. The future challenges of this important technology are also summarized.
基金the National High Technology Research and Development Program of China(2006AA030202,2006AA05Z316)
文摘Microreaction technology is one of the most innovative and rapid developing fields in chemical engineering, synthesis and process technology. Many expectations toward enhanced product selectivity, yield and purity, improved safety, and access to new products and processes are directed to the microreaction technology. Microfluidic mixer is the most important component in microfluidic devices. Based on various principles, active and passive micromixers have been designed and investigated. This review is focused on the recent developments in microfluidic mixers. An overview of the flow phenomena and mixing characteristics in active and passive micromixers is presented, including the types of physical phenomena and their utilization in micromixers. Due to the simple fabrication technology and the easy implementation in a complex microfluidic system, T-micromixer is highlighted as an example to illustrate the effect of design and operating parameters on mixing efficiency and fuid flow inside microfluidic mixers.
基金Supported by the Natural Science Foundation of Tianjin （07JCZDJC02600）.
文摘Using the multiple reference frames （MRF） impeller method, the three-dimensional non-Newtonian flow field generated by a double helical ribbon （DHR） impeller has been simulated. The velocity field calculated by the numerical simulation was similar to the previous studies and the power constant agreed well with the experimental data. Three computational fluid dynamic （CFD） methods, labeled Ⅰ, Ⅱ and Ⅲ, were used to compute the Metzuer constant k5. The results showed that the calculated value from the slop method （method Ⅰ） was consistent with the experimental data. Method Ⅱ, which took the maximal circumference-average shear rate around the impeller as the effective shear rate to compute ks, also showed good agreement with the experiment. However, both methods suffer from the complexity of calculation procedures. A new method （method Ⅲ） was devised in this paper to use the area-weighted average viscosity around the impeller as the effective viscosity for calculating k5. Method Ⅲ showed both good accuracy and ease of use.
文摘Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems.
文摘Steady-state non-dominated sorting genetic algorithm (SNSGA), a new form of multi-objective genetic algorithm, is implemented by combining the steady-state idea in steady-state genetic algorithms (SSGA) and the fitness assignment strategy of non-dominated sorting genetic algorithm (NSGA). The fitness assignment strategy is improved and a new self-adjustment scheme of is proposed. This algorithm is proved to be very efficient both computationally and in terms of the quality of the Pareto fronts produced with five test problems including GA difficult problem and GA deceptive one. Finally, SNSGA is introduced to solve multi-objective mixed integer linear programming (MILP) and mixed integer non-linear programming (MINLP) problems in process synthesis.
文摘This study aimed to identify and to analyze characteristics of top-cited articles published in the Web of Science chemical engineering subject category from 1899 to 2011.Articles that have been cited more than 100 times were assessed regarding publication outputs,and distribution of outputs in journals.Five bibliometric indicators were used to evaluate source countries,institution and authors.A new indicator,Y-index,was created to assess quantity and quality of contribution to articles.Results showed that 3828 articles,published between 1931 and 2010,had been cited at least 100 times.Among them 54% published before 1991,and 49% top-cited articles originated from US.The top eight productive institutions were all located in US.The top journals were Journal of Catalysis,AIChE Journal,Chemical Engineering Science and Journal of Membrane Science.Y-index was successfully applied to evaluate publication character of authors,institutions,and countries/regions.
基金Supported by the Natural Science Foundation of Guangdong Province (No. 990630) and the State Major Basic Research Development Program (No. G20000263).
文摘A method for incorporation of controlling the heat exchanger networks with or without splits is proposed by integrating mathemati-cal programming and knowledge engineering. The simultaneous optimal mathematical model is established. This method can be practically used in the integration of large-scale heat exchanger networks, not only to synthesize automatically but also to satisfy the requirement of struc-tural controllability with more objective human intervention.
基金Supported by the National Natural Science Foundation of China （50776023） and NSFC-Petro China （20490200）.
文摘Behavior of catalytic cracking reactions of particle cluster in fluid catalytic cracking （FCC） riser reactors was numerically analyzed using a four-lump mathematical model. Effects of the cluster porosity, inlet gas velocity and temperature, and coke deposition on cracking reactions of the cluster were investigated. Distributions of temperature, gases, and gasoline from both catalyst particle cluster and an isolated catalyst particle are presented. The reaction rates from vacuum gas oil （VGO） to gasoline, gas and coke of individual particle in the cluster are higher than those of the isolated particle, but it reverses for the reaction rates from gasoline to gas and coke. Less gasoline is produced by particle clustering. Simulated results show that the produced mass fluxes of gas and gasoline increase with the operating temperature and molar concentration of VGO, and decrease due to the formation of coke.
基金Supported by the National Natural Science Foundation of China (No. 29706006) and the General Corporation of Petrochemical Engineering of China (No.X598021).
文摘The local gas-phase flow characteristics such as local gas holdup(εg), local bubble velocity (V_b) and local bubble mean diameter(d_b) at a specified point in a gas-liquid-solid three-phase reversedflow jet loop reactor was experimentally investigated by a five-pointconductivity probe. The effects of gas jet flow rate, liquid jet flowrate, solid loading, nozzle diameter and axial position on the localεg, V_b and d_b profiles were discussed. The presence of solids atlow solid concentrations not only increased the local εg and V_b,but also decreased the local d_b. The optimum solid loading for themaximum local εg and V_b together with the minimum local d_b was0.16×10^-3 m^3, corresponding to a solid volume fraction ε_S＝2.5/100.
基金Supported by the National Natural Science Foundation of China(N.59831030).
文摘Erosion-corrosion of liquid-solid two-phase flow occurring in a pipe with sudden expansion in cross-section is numerically simulated in this paper. The global model for erosion-corrosion process includes three main components: the liquid-solid two-phase flow model, erosion model and corrosion model. The Eulerian-Lagrangian approach is used to simulate liquid-solid two-phase flow, while the stochastic trajectory model was adopted to obtain properties of particle phase. Two-way coupling effect between the fluid and the particle phase is considered in the model. The accuracy of the models is tested by the data in the reference. The comparison shows that the model is basically correct and feasible.
基金Supported by national "973" Key Project(G1999022102) and National High-Tech R&D Project(863) (2003AA522032)
文摘Introduced the application and development status of coal gasification tech- nology in China. The most widely used coal gasification technology in China is the at- mospheric fixed-bed gasifier, its total number is about 9 000. About 30 pressurized fixed-bed gasifiers are in operation, and more than 10 atmospheric fluidized-bed gasifi- ers were used. There are 13 Texaco entrained-flow bed gasifiers are under operation, 10 Texaco and 11 Shell gasifiers that are being installed or imported. About 10 under- ground gasifiers are under running now. The present R&D of coal gasification technolo- gies are to improve the operation and controlling level of fixed-bed gasification technol- ogy, and developing or demonstration of fluidized-bed and entrained-flow bed gasifiers.
文摘In recent decades,colleagues working in the Discipline of Geological Resources and Geological Engineering at Central South University made significant progress in theoretic study and application of geophysics,ore deposit and shale gas geology,3 D predictive modeling of concealed resources,and geological engineering.In geophysics,world-class progress was achieved in the development,data processing,equipment,and scientific survey of electromagnetic method in onshore and offshore environments and the tectonic evolution of the Tibetan Plateau.Especially,advanced wide-field electromagnetic exploration method and equipment as a highlight technique won the first prize of National Science and Technology Invention of China.In ore geology,progressive and complex characteristics of most nonferrous ore deposits and the geodynamic relationship between crust-mantle reaction and mineralization in south China were revealed.Progressive metallogenic models of certain typical ore deposits were established based on the study of fluid inclusion and geochemistry.According to characteristics of complex metallogenic system of polygenetic ore deposit,key ore-controlling factors were found and summarized.The investigation on unconventional resources advanced China’s shale gas resource evaluation system.In 3 D predictive modelling of metallogenic,a large-scale location prediction model was established for exploration of crisis mines and concealed ore deposits.Our developed 3 D predictive modeling techniques for concealed orebodies were widely used to explore deep mineral resources in China.In geological engineering area,the key technologies for deep drilling into complex formations were developed.Especially the drilling fluid and tools were utilized in the fieldwork.The rock and soil mechanics analysis method and anchor technologies were also established and applied to engineering practice.
基金Supported by the Natural Science Foundation of Guangdong Province (No. 990630) and the State Major Basic Research Development Program (G20000263).
文摘A new superstructure form of heat exchanger networks (HEN) isproposed based on expert system system (ES). The new superstructureform is combined with the practical engineering. The differentinvestment cost formula for Different heat exchanger is alsopresented based on ES. The mathematical model for the simultaneousoptimization Of network configuration is established and solved by agenetic algorithm. This method can deal with larger scale HENsynthesis and the optimal HEN configuration is obtainedautomatically. Finally, a case study is presented to Demonstrate theeffectiveness of the method.
