乙烯装置碳二加氢反应器动态建模与控制

Dynamic simulation and control of acetylene hydrogenation reactor in ethylene plant

乙烯装置碳二加氢反应过程是乙烯工艺流程中非常重要的一个环节,本身具有复杂性,现场装置的反应过程和实验室的机理研究有很大出入,同时碳二加氢反应非常灵敏,且处于生产流程的中部,可变的操作条件较少,精确操作比较困难。因而对碳二加氢反应过程的研究是目前国内乙烯装置技术改造的一个重要内容。本文基于乙烯装置中碳二加氢反应过程机理,采用HYSYS流程模拟软件建立了加氢反应器的稳态和动态模型。通过对模拟结果与实际工业过程数据的对比表明,模型的误差在5%以内,能够满足工业过程建模的要求。同时,本文对碳二加氢反应器的常规PID控制方案进行了测试,针对反应器进料温度的变化和氢炔比的变化,分析了反应器的动态响应,讨论了不同进料工况下的操作条件对反应过程的影响。结果表明,碳二加氢反应器控制方案在反应条件变化时是稳定的,可以用于指导实际生产。

Acetylene hydrogenation reactor in ethylene plant is very important in ethylene process. It is complex, the reaction process in plant and reaction mechanism in laboratory differ materially. Also, acetylene hydrogenation reactor is very sensitive. Because it happens in the middle of ethylene process, the reactor has tess variable operating conditions, and more difficult accurate operations. For the above reasons, researches on acetylene hydrogenation reactor are important technological contents in transformation of ethylene plant. This paper develops the steady-state and dynamic model of acetylene hydrogenation reactor in ethylene plant. It is based on the mechanism, using the commercial software HYSYS. The results of the model are 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 was under control and the control strategy can bc used to guide the practical production.