Operation Optimization Of Chemical Process Based On Integration Of PRO/â…¡ And Excel And GA

The process simulation software PRO/Ⅱ has a strong physical database and rich in thermodynamic models and unit operation modules. The PRO/Ⅱ can be used in chemical process simulation, design and optimization. But the PRO/Ⅱ is lack in some functions like data processing and automatic optimization; we can solve these problems by software integration technology.In this article, using the interactive function of the COM server of the PRO/Ⅱ software and other software, an interface program between the PRO/Ⅱ software and the Excel software was worked out in Visual Basic for Applications(VBA) of Excel software. The PRO/Ⅱ is to simulate the specific chemical process as a simulator; the interface is responsible for transferring the date between Excel and PRO/Ⅱ. Through the integration of the two software, the PRO/Ⅱ can be controlled in the Excel, and the parameters of PRO/Ⅱ software model can be automatically modified. Using the integrated software read and write target datas will be conveniently, and we can using this method to replace the repeat operation by hand, then we can save time and improve the computational efficiency.Then, the program of genetic algorithm was worked out, and the integration of PRO/Ⅱ software,Excel software and genetic algorithm was realized. Genetic algorithm generate parameters for PRO/Ⅱ software simulating and select the excellent parameters according to the simulation results of PRO/Ⅱ software. The multi-objective Genetic Algorithm was also worked out and the integration realize the multi objective optimization function.By the integration,the main fractional column and absorption-stabilization system in a 1.2Mt/a FCC unit were optimized. First, the single variable simulation analysis is performed to demonstrate the convenience the integration in lager number calculation and reading and writing simulation datas. Second, set maximize economic benefits of the unit as the target with three variables, which increased the economic benefits of the unit by 904.3 yuan/h. Third, using 7℃circulation cooling water instead some common circulation cooling water, and added a new heat exchanger, which increased the economic benefits of the unit by 1685.6 yuan/h. Fourth, the multi-objective optimization of the system was realized, set dry gas quality and heating duty and cooling duty as the targets. Pareto optimal solutions were foud by the integration; and we find that practical operation is not optimal; we can get better dry gas quality using the same duty.In this article, the integrated software is not only suitable for the FCC unit, but also can be applied to other chemical processes which can be simulated in PRO/Ⅱ software. For china’s chemical industry, this has important practical significance to improve economic efficiency and reduce energy consumption, to improve designing and operating level of unit and to reduce the gap between our country and foreign advanced countries.