The Research And Application Of Chloroacetic Acid Crystallization Process Control

Chloroacetic acid is widely used in pesticides, pharmaceuticals, dyes and other industries as one of the important basic chemical raw materials. In recent years, with the rapid economy development, the market needs of chloroacetic acid is growing fast in domestic and foreign. The chloroacetic acid’s interal producing needs two steps: chlorination and crystallization. The yield and quality of the finished product is directly related to the crystallization process. In the process of chloroacetic acid crystallization, the temperature control of crystallization reactor is not very ideal, resulting in low product quality, which is a long-term challenges the chloroacetic acid industry need to face. So the advanced intelligent algorithm is adopted to design the controller, in order to meet the requirements of temperature control, getting rid of the traditional PID and manual operation.How to receive chloroacetic acid production of high-quality and high-yield, is always the research focus in the chloroacetic acid production plant and domestic and foreign research institutions. This paper design a reasonable control program of chloroacetic acid crystallization combined with the actual production of chloroacetic acid factory and process requirements. The kettle contents temperature must accord to certain trends in the process of chloroacetic acid crystallization, which control requirement is relatively high. Therefore, pouring the mixing water of preheated tank into the crystallization kettle jacket to maintain kettle temperature in industrial production. In this paper, the Fuzzy Smith intelligent method and RBF-PID algorithm are proposed to control the preheated tank and crystallization kettle temperature respectively, with the controlled object characteristics of time-varying, large inertia and lag. The MATLAB Simulation results show that the control effect of the designed controllers is superior to the traditional algorithms. At the end of the paper, chloroacetic acid crystallization production process is simulated by using MCGS configuration, which can display the real-time and historical data of preheated tank and crystallization kettle temperature, and achieve alarm function of preheated tank level.