Reconstruction For Caustic Wash Tower Of Vinyl Chloride Device In Chloric Alkali Productio

There are a lot of control problems that we can study on industrial production process,especially in the age of fast development of industry and information,improving automation system is necessary,and PH control is one of it,it also make great effect directly to the quality of products,products life and environment pollution of industrial production process.This paper aim at PH control problem of operating fluid of a chlor-alkali chemical enterprises for the actual production of vinyl chloride plant in alkaline washing tower,start from the analysis of user needs and the mechanism of pH control process,through accessing to a large number of domestic and foreign literature,and combining with the actual production process on-site operation,analyzed the factors that influencing the process of the pH value control of the caustic washing tower in the plant,including the operating mechanism of the caustic scrubber itself under different process flow conditions,and the impact of acid,alkali flow,concentration,liquid level for pH control accuracy,and then,a mathematical model for the neutralization of the caustic scrubber was established,obtained nonlinear characteristic of pH value in the control process.In view of the complexity of technology changes for actual production process,and put forward the solution creatively of the combination of equipment specialty and control specialty to solve the control problem.Through the transformation of equipment structure of the alkaline washing tower,make tower liquid level,working pressure and circulation of working fluid of of different working conditions stable,and the goal of reducing influencing factors in pH value control of tower working fluid is realized,reduced input variables for pH controller design,and the paper used the Matlab software to have done simulation experiments of the conventional PID control and fuzzy PID control program that presented in this paper,different simulation results were obtained.After comparison,the conclusion is that fuzzy PID control has smaller overshoot and shorter response time than conventional PID control,fuzzy PID control is more suitable for pH control process.