Steady-state, Dynamic Simulation And Optimization Of Acetylene Hydrogenation Reactor In Ethylene Plant

C2 hydrogenation reactor is an essential equipment of ethylene process. In reality, the quality and quantity of ethylene are directly decided by acetylene conversion and hydrogenation selective in this reactor. Because the hydrogenation process is very complex, the reaction mechanism in laboratory can't be directly used in the industrial process. Meanwhile, C2 hydrogenation reactor is in the middle of ethylene process which has less variable operating conditions and is difficult to be accurately operated. Therefore, modeling and optimization techniques of acetylene hydrogenation reactor are significant to improve the ethylene product quality, make production stable and improve economic efficiency.This study developed the steady-state and dynamic model of acetylene hydrogenation reactor in ethylene plant based on the mechanism. The commercial software HYSYS was used as the platform for the modeling. With acquiring industrial process data, kinetic parameters were fitted using the traditional least square method in order to make the model consistent with real process. The results of the model were compared with industrial operating data. It shows that the error is below 5% and the model is suitable for the simulation of industrial reactor. Also, a conventional PID approach to control the aforementioned reactor is tested. By analyzing the dynamic responses according to the changes of feed temperature and hydrogen-acetylene ratio of the reactors, the effects of different load are discussed. The results show that the reactor is under control and the control strategy can be used to guide the practical production.Since the convergence of standard particle swarm optimization is difficult, a control factor being obtained by chemical prior knowledge was introduced into the formula to update particle's velocity, which was used to adjust the particle's position to improve the input variables of model. The products can meet the technical requirements of each component compositions. Sensitivity analysis, based on the model, for operation variables of hydrogenation reactor determine the optimization scheme, and the improved PSO is used to optimize operation variables. Simulation results show that optimization measures, such as reducing the feed temperature of reactor, increasing hydrogenation flow, can effectively improve acetylene conversion and hydrogenation selective for C2 hydrogenation reactor.