Feasibility Analysis Of Heat-Integration Reactive Distillation Column

In modern times, the problem of energy resources has always been focused by all countries in the world, especially after the two crises of petroleum. Every country is paying high attention to the problem of energy resources. The problem is more obvious in the chemical industry as the chemical industry is energy intensive industries and the energy consumption is very huge, especially in separation process. Compared with traditional distillation column, heat integration technology shows the advantages of less energy consumption and low capital investment. Hence, how to maximize the advantages of heat integration of the reactive distillation column has become the hot point home and abroad nowadays and it is also the research theoretical basis of this paper.This paper mainly discusses two kinds of heat integration, the internal heat integration and the external heat integration. The internal heat integration is realized between the rectifying section and the stripping section of a single distillation column. In order to keep the temperature difference between the stripping section and the rectifying section, the ascending vapor flow from the stripping section is sent into the compressor to increase the pressure. Compared with the internal heat integration, the external heat integration is operated between two individual distillation columns with different operating pressures.In the traditional reactive distillation column, the product from the top of the distillation column needs to be condensed in the condenser and the product from the bottom needs to be vaporized by reboiler. In this case, the traditional reactive distillation column shows the disadvantage of high energy consumption and low thermodynamic effect. In the internal heat-integrated reactive distillation column (IHIRDC), the reaction zone is divided into a high pressure section and a low pressure section to achieve the heat transfer. The basic theory of external heat integration is to increase the pressure of reactive column. On that situation, the temperature of the condenser in the top of the high pressure column will be higher than that of the low pressure column. The temperature difference makes the heat transfer possible and the energy from the condenser in the top of high pressure column can be recycled. Also external heat integration includes rectifying section/stripping section heat integration and condenser/reboiler heat integration.In this paper, the reactive distillation system including an ideal reactive distillation column separating a hypothetical reaction, A+B(?)C +D, is employed to study and compare the following three systems:the conventional reactive distillation system, the reactive distillation system with internal heat integration and the reactive distillation system with external heat integration. Finally an optimum reactive distillation system in obtained based on the goal function of total annual costs (TAC).