Simultaneous Optimization Of Reaction Path And Reactor Network

Reaction process optimization includes the reaction path synthesis and reactor network synthesis. Reaction path synthesis deals with determining the chemical reaction path which converts the given raw reactants to desired products. Reactor network synthesis involves determining the type, size and interconnections of the reactor units, optimal concentrations and temperature profiles of the process. There are many research ideas and optimization methods for reaction path and reactor network synthesis. With the expansion of the field of research and the improvement of the system complexity, the demand of optimization method has also been gradually increasing, it is important and necessary to propose a practical, simple and universal reaction process optimization method. There are many researches on several aspects, such as expanding the field of optimization method, improving the real degree of mathematical model, combining the approaches of reaction process optimization and exploring deeply the synthesis and optimization of reaction process.Firstly, there is only one kind of catalyst in research field of traditional attainable region method, and kinetic parameters of reaction system is constant. As for real production, how to filter the catalyst and how to determine the arrangement of several catalysts are very important problem related to the production planning and economic parameters, taking the use of attainable region method to study several catalysts reaction process has great realistic meaning and industrial demand. The steps and basic rules that attainable region method deals with several catalysts reaction process are proposed, and they are used in traditional Van de Vusse reaction system with two catalysts. The optimal reactor network is two series PFR, and the optimal catalyst arrangement is catalyst 1 before catalyst 2.Secondly, the’three steps strategy’named attainable region-superstructure strategy for the synthesis of chemical reactor networks is proposed, which has complementary advantages between attainable region and superstructure-based approach provides a new point of view to synthesis chemical reactor network. This strategy has been successfully applied to epoxy propane reaction system, feed flow rate is 9.54L/h with 2.485mol/L propylene and 0.834mol/L hydrogen peroxide. If choose the maximal desired production concentration as the objective function regardless of the equipment investment, the optimal reactor network gets the concentration of epoxy propane is 0.783mol/L; if choose the minimum annual total cost as the objective function, the optimal reactor network gets minimum annual total cost is $208.397, and the concentration of epoxy propane is 0.743mol/L.Thirdly, reaction path synthesis concerns the choose of chemical reaction path rather than the design of reactor, while reactor network synthesis optimizes the optimal reactor network in determined reaction path, there are many connections between the two reaction process optimizing methods. Traditional reaction process optimizing methods have limitations, taking the arrangement of functional catalysts as breakthrough point, superstructure-based method of simultaneous optimization of reaction path and reactor network is proposed in this article. Then a reaction process optimization of p-xylene is illustrated to achieve an optimal design through the method proposed, choosing C8 aromatics isomerization, toluene disproportionation and toluene alkylation production process and theirs functional catalysts as the research object. The optimal reaction process is C8 aromatics isomerization after toluene alkylation production process, compared with a single functional catalyst of toluene alkylation reaction network, optimal reactor networks loaded a variety of functional catalysts increased the yield of p-xylene by 22.73 percent over the same time period, the method proposed is demonstrated to be effective.