The high degree of reversibility of heat integrated distillation column(HIDiC) has been thermodynamically interpreted by the entropy method. In this paper, a heat transfer model and a more universal method were propos...The high degree of reversibility of heat integrated distillation column(HIDiC) has been thermodynamically interpreted by the entropy method. In this paper, a heat transfer model and a more universal method were proposed, through which the overall heat transfer coefficient at different height of column under different operating conditions could be obtained before the experiment. Then the separation of a binary ethanol-water system was carried out experimentally as a case study to verify the heat transfer model and the aforementioned calculation method. The close results between the calculation, the simulation, and the experiments suggested that the proposed model and the calculation method in this paper were accurate and applicable. Meanwhile, it was demonstrated that the HIDiC shows obvious effect of reducing entropy increase and improving thermodynamic efficiency as compared to conventional distillation column.展开更多
In the realm of the synthesis of heat-integrated distillation configurations,the conventional approach for exploring more heat integration possibilities typically entails the splitting of a single column into a twocol...In the realm of the synthesis of heat-integrated distillation configurations,the conventional approach for exploring more heat integration possibilities typically entails the splitting of a single column into a twocolumn configuration.However,this approach frequently necessitates tedious enumeration procedures,resulting in a considerable computational burden.To surmount this formidable challenge,the present study introduces an innovative remedy:The proposition of a superstructure that encompasses both single-column and multiple two-column configurations.Additionally,a simultaneous optimization algorithm is applied to optimize both the process parameters and heat integration structures of the twocolumn configurations.The effectiveness of this approach is demonstrated through a case study focusing on industrial organosilicon separation.The results underscore that the superstructure methodology not only substantially mitigates computational time compared to exhaustive enumeration but also furnishes solutions that exhibit comparable performance.展开更多
The optimal performance of heat-driven binary separation processes with linear phenomenological heat transfer law(q∝△(T-1)) is analyzed by taking the processes as heat engines which work between high-and low-tempera...The optimal performance of heat-driven binary separation processes with linear phenomenological heat transfer law(q∝△(T-1)) is analyzed by taking the processes as heat engines which work between high-and low-temperature reservoirs and produce enthalpy and energy flows out of the system,and the temperatures of the heat reservoirs are assumed to be time-and space-variables.A numerical method is employed to solve convex optimization problem and Lagrangian function is employed to solve the average optimal control problem.The dimensionless entropy production rate coefficient and dimensionless enthalpy flow rate coefficient are adopted to indicate the major influence factors on the performance of the separation process,such as the properties of different materials and various separation requirements for the separation process.The dimensionless minimum average entropy production rate and dimensionless minimum average heat consumption of the heat-driven binary separation processes are obtained.The obtained results are compared with those obtained with the Newtonian heat transfer law(q∝△(T)).展开更多
基金supported by the National Key Research and Development Program of China(2017YFB0602500)the Foundation for High Level Talents of Hebei (A2017002032).
文摘The high degree of reversibility of heat integrated distillation column(HIDiC) has been thermodynamically interpreted by the entropy method. In this paper, a heat transfer model and a more universal method were proposed, through which the overall heat transfer coefficient at different height of column under different operating conditions could be obtained before the experiment. Then the separation of a binary ethanol-water system was carried out experimentally as a case study to verify the heat transfer model and the aforementioned calculation method. The close results between the calculation, the simulation, and the experiments suggested that the proposed model and the calculation method in this paper were accurate and applicable. Meanwhile, it was demonstrated that the HIDiC shows obvious effect of reducing entropy increase and improving thermodynamic efficiency as compared to conventional distillation column.
文摘In the realm of the synthesis of heat-integrated distillation configurations,the conventional approach for exploring more heat integration possibilities typically entails the splitting of a single column into a twocolumn configuration.However,this approach frequently necessitates tedious enumeration procedures,resulting in a considerable computational burden.To surmount this formidable challenge,the present study introduces an innovative remedy:The proposition of a superstructure that encompasses both single-column and multiple two-column configurations.Additionally,a simultaneous optimization algorithm is applied to optimize both the process parameters and heat integration structures of the twocolumn configurations.The effectiveness of this approach is demonstrated through a case study focusing on industrial organosilicon separation.The results underscore that the superstructure methodology not only substantially mitigates computational time compared to exhaustive enumeration but also furnishes solutions that exhibit comparable performance.
基金Supported by the Program for New Century Excellent Talents of China (Grant No. NCET-04-1006)the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 200136)
文摘The optimal performance of heat-driven binary separation processes with linear phenomenological heat transfer law(q∝△(T-1)) is analyzed by taking the processes as heat engines which work between high-and low-temperature reservoirs and produce enthalpy and energy flows out of the system,and the temperatures of the heat reservoirs are assumed to be time-and space-variables.A numerical method is employed to solve convex optimization problem and Lagrangian function is employed to solve the average optimal control problem.The dimensionless entropy production rate coefficient and dimensionless enthalpy flow rate coefficient are adopted to indicate the major influence factors on the performance of the separation process,such as the properties of different materials and various separation requirements for the separation process.The dimensionless minimum average entropy production rate and dimensionless minimum average heat consumption of the heat-driven binary separation processes are obtained.The obtained results are compared with those obtained with the Newtonian heat transfer law(q∝△(T)).
