As a major configuration of membrane elements,multi-channel porous inorganic membrane tubes were studied by means of theoretical analysis and simulation.Configuration optimization of a cylindrical 37-channel porous in...As a major configuration of membrane elements,multi-channel porous inorganic membrane tubes were studied by means of theoretical analysis and simulation.Configuration optimization of a cylindrical 37-channel porous inorganic membrane tube was studied by increasing membrane filtration area and increasing permeation efficiency of inner channels.An optimal ratio of the channel diameter to the inter-channel distance was proposed so as to increase the total membrane filtration area of the membrane tube.The three-dimensional computational fluid dynamics(CFD) simulation was conducted to study the cross-flow permeation flow of pure water in the 37-channel ceramic membrane tube.A model combining Navier–Stokes equation with Darcy's law and the porous jump boundary conditions was applied.The relationship between permeation efficiency and channel locations,and the method for increasing the permeation efficiency of inner channels were proposed.Some novel multichannel membrane configurations with more permeate side channels were put forward and evaluated.展开更多
In this work, the extractive distillation with heat integration process is extended to separate the pressure-insensitive benzene-cyclohexane azeotrope by using furfural as the entrainer. The optimal design of extracti...In this work, the extractive distillation with heat integration process is extended to separate the pressure-insensitive benzene-cyclohexane azeotrope by using furfural as the entrainer. The optimal design of extractive distillation process is established to achieve minimum energy requirement using the multi-objective genetic algorithm, and the results show that energy saving for this heat integration process is 15.7%. Finally, the control design is performed to investigate the system's dynamic performance, and three control structures are studied. The pressure-compensated temperature control scheme is proposed based on the first two control structures, and the dynamic responses reveal that the feed disturbances in both flow rate and benzene composition can be mitigated well.展开更多
Through a great deal calculation, the design and simulation analysis of stator parametric and rotor electromagnetic system of 1000MW turbo-generator are performed by using Ansoft Maxwell Rmxprt12.1 software. Besides. ...Through a great deal calculation, the design and simulation analysis of stator parametric and rotor electromagnetic system of 1000MW turbo-generator are performed by using Ansoft Maxwell Rmxprt12.1 software. Besides. the basic parameters of the generator, the geometry dimensions of the stator and rotor, type and sizes of the slots, coils and windings parameters and the way of windings connection are determined. The finite element model of electromagnetic systems of generator stator and rotor was constructed by Ansoft Maxwe112D3D 12.1, and the transient electromagnetic characteristics of generator was analyzed and simulated. The 3D geometric models of turbo-generator were established respectively by using PROE software, and the dynamic finite element model of generator structure was built by ANSYS workbench 11.0. In addition, the dynamic characteristics of stator iron core, stator frame were calculated respectively. The simulation calculation has shown that the structural parameters, material parameters, and the electromagnetic characteristics parameters for large turbogenerator that are put forward by this paper should be optimal. and the design plan and method suggested by this paper should be feasible. The paper provides an effective solution for the development of larger turbo-generator than 1000 MW.展开更多
This paper focuses on the dynamic control of distillation column with side reactors(SRC) for methyl acetate production. To obtain the optimum integrated structure and steady state simulation, the systematic design app...This paper focuses on the dynamic control of distillation column with side reactors(SRC) for methyl acetate production. To obtain the optimum integrated structure and steady state simulation, the systematic design approach based on the concept of independent reaction amount is applied to the process of SRC for methyl acetate production. In addition to the basic control loops, multi-variable model predictive control modular with methyl acetate concentration and temperature of sensitive plate is designed. Then, based on process simulation software Aspen Plus, dynamic simulation of SRC for methyl acetate production is used to verify the effectiveness of the control scheme.展开更多
Limiting anthropogenic climate change to below 2°C requires substantial and rapid reductions in greenhouse gas emissions.Additionally,carbon dioxide removal technologies are essential to compensate for hard-to-ab...Limiting anthropogenic climate change to below 2°C requires substantial and rapid reductions in greenhouse gas emissions.Additionally,carbon dioxide removal technologies are essential to compensate for hard-to-abate emissions and counteract overshooting the earth’s carbon budget.One prospective technology is direct air carbon capture and storage(DACCS),but its energy intensity and costs limit large-scale deployment.Flexible DACCS operation seems promising for cost reduction but yet remains underexplored.This study explores the economic benefits of flexible operation of adsorption-based DACCS,considering fluctuations in both electricity prices and greenhouse gas emissions from the electricity supply.To increase the feasibility of flexible DACCS operation,the typical steam-assisted temperature vacuum swing adsorption cycle is enhanced by introducing two break phases and variable air and steam mass flows during adsorption and desorption.The benefits of flexible operation are comprehensively evaluated using a DACCS system model integrating a detailed dynamic process model with life-cycle greenhouse gas emissions and economic data.The flexible operation allows each cycle to be adjusted to optimally address the time-varying greenhouse gas emissions and costs from electricity supply.A rolling horizon algorithm combined with particle swarm optimization is used to optimize the DACCS cycles in flexible operation mode over one week.The case study focuses on the future German power grid and a DACCS system using amine-functionalized sorbents.Results indicate that flexible DACCS operation can significantly reduce net carbon removal costs by up to 20%compared to a steadystate operation.These findings highlight the potential of flexible DACCS operation to support carbon neutrality efforts by enabling cost-effective carbon dioxide removal through integration with volatile renewable energy systems.展开更多
基金Supported by the National Basic Research Program of China(2012CB224806)the National Natural Science Foundation of China(21490584,21476236)the National High Technology Research and Development Program of China(2012AA03A606)
文摘As a major configuration of membrane elements,multi-channel porous inorganic membrane tubes were studied by means of theoretical analysis and simulation.Configuration optimization of a cylindrical 37-channel porous inorganic membrane tube was studied by increasing membrane filtration area and increasing permeation efficiency of inner channels.An optimal ratio of the channel diameter to the inter-channel distance was proposed so as to increase the total membrane filtration area of the membrane tube.The three-dimensional computational fluid dynamics(CFD) simulation was conducted to study the cross-flow permeation flow of pure water in the 37-channel ceramic membrane tube.A model combining Navier–Stokes equation with Darcy's law and the porous jump boundary conditions was applied.The relationship between permeation efficiency and channel locations,and the method for increasing the permeation efficiency of inner channels were proposed.Some novel multichannel membrane configurations with more permeate side channels were put forward and evaluated.
基金supported by the National Natural Science Foundation of China(grant number 21476261)the Key Research and Development Plan Project of Shandong Province(grant number 2015GGX107004)
文摘In this work, the extractive distillation with heat integration process is extended to separate the pressure-insensitive benzene-cyclohexane azeotrope by using furfural as the entrainer. The optimal design of extractive distillation process is established to achieve minimum energy requirement using the multi-objective genetic algorithm, and the results show that energy saving for this heat integration process is 15.7%. Finally, the control design is performed to investigate the system's dynamic performance, and three control structures are studied. The pressure-compensated temperature control scheme is proposed based on the first two control structures, and the dynamic responses reveal that the feed disturbances in both flow rate and benzene composition can be mitigated well.
文摘Through a great deal calculation, the design and simulation analysis of stator parametric and rotor electromagnetic system of 1000MW turbo-generator are performed by using Ansoft Maxwell Rmxprt12.1 software. Besides. the basic parameters of the generator, the geometry dimensions of the stator and rotor, type and sizes of the slots, coils and windings parameters and the way of windings connection are determined. The finite element model of electromagnetic systems of generator stator and rotor was constructed by Ansoft Maxwe112D3D 12.1, and the transient electromagnetic characteristics of generator was analyzed and simulated. The 3D geometric models of turbo-generator were established respectively by using PROE software, and the dynamic finite element model of generator structure was built by ANSYS workbench 11.0. In addition, the dynamic characteristics of stator iron core, stator frame were calculated respectively. The simulation calculation has shown that the structural parameters, material parameters, and the electromagnetic characteristics parameters for large turbogenerator that are put forward by this paper should be optimal. and the design plan and method suggested by this paper should be feasible. The paper provides an effective solution for the development of larger turbo-generator than 1000 MW.
基金Supported by the National Natural Science Foundation of China(61673205,61503181,21727818)National Key R&D Program of China(2017YFB0307304)+1 种基金the Natural Science Foundation of Jiangsu Province(BK20141461,BK20140953)the State Key Laboratory of Materials-Oriented Chemical Engineering Open Subject(kl16-07)
文摘This paper focuses on the dynamic control of distillation column with side reactors(SRC) for methyl acetate production. To obtain the optimum integrated structure and steady state simulation, the systematic design approach based on the concept of independent reaction amount is applied to the process of SRC for methyl acetate production. In addition to the basic control loops, multi-variable model predictive control modular with methyl acetate concentration and temperature of sensitive plate is designed. Then, based on process simulation software Aspen Plus, dynamic simulation of SRC for methyl acetate production is used to verify the effectiveness of the control scheme.
基金This work has been carried out within the project MoGaTEx(01LY2001B)funded by the German Federal Ministry of Education and Research(BMBF)in the founding initiative"KMU-innovativ".
文摘Limiting anthropogenic climate change to below 2°C requires substantial and rapid reductions in greenhouse gas emissions.Additionally,carbon dioxide removal technologies are essential to compensate for hard-to-abate emissions and counteract overshooting the earth’s carbon budget.One prospective technology is direct air carbon capture and storage(DACCS),but its energy intensity and costs limit large-scale deployment.Flexible DACCS operation seems promising for cost reduction but yet remains underexplored.This study explores the economic benefits of flexible operation of adsorption-based DACCS,considering fluctuations in both electricity prices and greenhouse gas emissions from the electricity supply.To increase the feasibility of flexible DACCS operation,the typical steam-assisted temperature vacuum swing adsorption cycle is enhanced by introducing two break phases and variable air and steam mass flows during adsorption and desorption.The benefits of flexible operation are comprehensively evaluated using a DACCS system model integrating a detailed dynamic process model with life-cycle greenhouse gas emissions and economic data.The flexible operation allows each cycle to be adjusted to optimally address the time-varying greenhouse gas emissions and costs from electricity supply.A rolling horizon algorithm combined with particle swarm optimization is used to optimize the DACCS cycles in flexible operation mode over one week.The case study focuses on the future German power grid and a DACCS system using amine-functionalized sorbents.Results indicate that flexible DACCS operation can significantly reduce net carbon removal costs by up to 20%compared to a steadystate operation.These findings highlight the potential of flexible DACCS operation to support carbon neutrality efforts by enabling cost-effective carbon dioxide removal through integration with volatile renewable energy systems.