Synthesis And Design Of Reactive Distillation Column With Multiple Reactive Sections

These years have witnessed great development of reactive distillation research. As a synthesis technology of reaction operation and separation operation, reactive distillation can solve many problems in reaction process and separation process, which lead to improvement of process efficiency and reduction of capital investment and operating. On the basis of a great deal of theoretical researches, the application of reactive distillation has brought enormous economic benefits in chemical industry.Conventional reactive distillation with a single reactive section (RDC-SRS) can solve the reaction system with a single reaction well. In the case of the separations of multiple-step consecutive reaction systems, RDC-SRS require large amounts of energy. It is difficult for RDC-SRS to achieving careful coordination of multiple reactions in a single reactive section, resulting in negative influence in aspect of internal mass integration and internal energy integration.A reactive distillation column with multiple reactive sections (RDC-MRS) is proposed in order to solve the problem of high energy consumption for the multiple-step consecutive reaction. The arrangements of multiple reactive sections allow the coordination of the several reactions involved, and provide additional degrees of freedom in order to reinforce the internal mass integration and internal energy integration. In the research of RDC-MRS, reactive distillation column with double reactive sections (RDC-DRS) and the reactive distillation column with three reactive sections (RDC-TRS) are basic and important structures, which are the key research contents in this paper.With the disproportionation of trichlorosilane to silane, the RDC-TRS and RDC-DRS are demonstrated to require less utility consumption than the RDC-SRS. Under the constraints that the total number of stages and the number of reactive stages are kept identical with the conventional RDC-SRS, the operating costs of RDC-TRS and RDC-DRS are decreased over 11% and about 9.2% respectively. This outcome indicates that the RDC-TRS and RDC-DRS could be competitive alternatives in the separations of the multiple-step consecutive reactions. Beyond that, the dividing-wall reactive distillation column with double reactive sections(DWRDC-DRS) is proposed. Even though the product purity does not meet the requirement due to the complicated reaction system, DWRDC-DRS has the capability of saving energy.