Influence analysis of process scheduling on optimized operation strategy of acetylene hydrogenation reactor

Acetylene hydrogenation reactor is an important device for removing small amounts of acetylene in high-concentration ethylene streams in the ethylene industry. The device generally runs for a long time, during which the catalyst activity in the reactor gradually decreases until the activity cannot meet the process requirements. The full cycle operation optimization of acetylene hydrogenation reactor should be carried out rigidly according to the operation optimization scheme within the operation cycle. However, in the actual industrial process, in order to meet the temporary process scheduling requirements, the operation plan of acetylene hydrogenation reactor needs to be temporarily changed in the remaining operation cycle after running in accordance with the operation optimization plan for a certain time, which brings more changes and challenges to the operation optimization problem. Based on margin estimation and control optimization framework of slow time varying systems, the full cycle dynamic optimization problem of temporarily changing the operation optimization scheme during the operation cycle is studied in this paper. The ways to change the operation optimization scheme include: changing operation cycle and pursuing economic benefit maximization, and changing optimization objective and pursuing operation cycle maximization.Through the analysis of these two optimization schemes for changing operation, it is found that the closer the operating cycle of the former is to the original operating cycle, the higher the total economic benefit of the whole cycle. The earlier the switching time of the latter, the longer the operating cycle that the reactor can maintain. However, the full-cycle economic benefits of both are inferior to the original operation optimization plan, and temporary process scheduling is generally unfavorable to the full-cycle optimized operation of the acetylene hydrogenation reactor. © 2021, Editorial Board of CIESC Journal. All right reserved.