应用动态模拟软件DYNSIM开展了异丙苯工艺苯塔自动控制的设计.使用PRO/II建立了苯塔系统的稳态模型,并分析了苯塔压力控制方式及调节阀难以选取的原因为在不同温度、压力以及氮气流量下丙烷在冷凝液中的溶解度变化较大,造成丙烷不凝气瞬间大量释放.通过研究认为采用分程控制调整该塔压力较为合理.采用建立的动态模型研究了在苯塔压力受到干扰后,分程控制方案不同控制曲线对调整塔顶压力的效果.结果表明,经过整定PID参数后,具有不凝气排放和氮气补充同时动作区域的分程控制方案能够在13分钟内调整塔压至设定值.以上研究表明动态模拟软件能够直观地体现化工装置的动态特性,为化工装置设计的安全可靠性提供支撑.
A benzene tower steady state simulation model is built in PRO/II based on Cumene Plant.The reason of difficult to lectotype column pressure control strategy and valve is because of noncondensable gas propane change caused by termperature,pressure and adding nitrogen flowrate.The column's dynamic simulation model is built in DYNSIM.Dynamic studies are conducted and the optimized pressure control strategy is obtained.A control curve with optimized PID parameters was determined that can adjust column pressure to set point effectively when it was disturbed.It is concluded that dynamic simulation is an intuitive way to show the dynamic behaviors of chemical process and thereby becomes a helpful tool for safe and efficient operations of the plant.