Study On Optimization Of Distillation-Membrane Separation Hybrid Processes For Alcohol-Water Azeotrope System Based On Genetic Programming

The separation of azeotrope is a difficult point in chemical production,so it is of great significance to study the new energy-saving separation process.In recent years,with the rapid development of pervaporation membrane separation technology,the distillation-pervaporation membrane separation hybrid processes have highlighted advantages.In this paper,a comprehensive solution strategy for the distillation-pervaporation membrane separation hybrid processes based on genetic programming is established.According to the characteristics of a certain azeotrope and the type of pervaporation membrane,the optimal distillation-pervaporation membrane separation hybrid processes can be quickly and accurately solved.The optimal equipment parameters and operating parameters in the process can be determined.The comprehensive solution strategy was used to study the separation of two azeotrope systems of isopropanol-water and tert-butanol-water with industrial applicability.This paper constructs a comprehensive solution strategy based on genetic programming.Firstly,it establishes a chemical professional knowledge base,which can effectively guide the algorithm code generation and evolution operation to meet the requirements of chemical industry.The comprehensive solution strategy includes the establishment of chemical node model library,the generation of tree code,initial population generation principles,individual fitness calculation,evolutionary operations and termination criteria settings.During the solution process,the structural variables and operating variables in the rectification-membrane separation integrated process flow are simultaneously involved in the optimization.By using the above-mentioned solving strategy,the optimal hybrid processes of the rectification-membrane separation of the azeotrope system can be quickly and accurately solved by matching the reasonable and feasible pervaporation membrane according to the separation requirement without determining the superstructure of the process,and find the best equipment and operating parameters.In this paper,an industrial case study is carried out by using the proposed comprehensive solution strategy.The hydrophilic PERVAP 2510 membrane was selected to calculate the different feed flow and feed composition of the two systems of isopropanol-water and tert-butanol-water respectively.The corresponding optimal integrated separation processes were searched and the optimal equipment and operation parameters are calculated.For the separation of isopropanol-water azeotrope system,the calculation results show that when the feed flow is small and the water content in feed is large,the optimal integration process searched by the algorithm is integrated series distillation-membrane separation process without reflux.When the feed flow is large and the water content in feed is small,the optimal integration process searched by the algorithm is integrated series distillation-membrane separation-distillation process with one reflux.For the separation of tert-butanol-water azeotrope system,the optimal integration process searched by the algorithm is integrated series distillation-membrane separation-distillation process with two-strand reflux.The cost changes of the above structures are analyzed.The above results fully meet the actual requirements of chemical production.The integrated solution strategy of the distillation-pervaporation membrane separation hybrid processes based on genetic programming proposed in this paper can be applied to the integrated design and calculation of other azeotrope separations in chemical production,which provides a reliable theoretical basis for solving similar problems.