串级均匀控制系统在深冷凝液回收装置中的应用

Application of Cascade-Averaging Control System in Cryogenic Condensate Recovery Unit

均匀控制系统既可以保持设备的液位或压力在一定的控制范围内,又可以保证流量在较小的范围内缓慢变化,使前后设备在物料供求上相互均匀、协调。均匀控制在工业生产过程中应用越来越广泛。为做好均匀控制系统的设计、投运和比例积分微分(PID)参数整定工作,通过对深冷凝液回收装置中脱甲烷塔和脱乙烷塔控制要求的研究,提出了控制液位与流量的串级均匀控制系统。介绍了该系统的控制规律选择原则和系统投运要点。详述了该系统的投运过程及PID参数整定过程,分析总结了控制效果。实际应用表明:串级均匀控制系统兼顾了液位控制与流量控制之间的矛盾;脱甲烷塔、脱乙烷塔的液位和流量均控制在要求范围内,且变化平缓;整个装置一次性投产成功后连续平稳运行。该系统在具有类似串联设备的连续工业生产过程中具有推广应用价值。

The averaging control system can keep the liquid level or the pressure of the equipment within a certain control range,and at the same time,it can ensure that the flow changes slowly within a small range,so that the adjacent equipments are uniform and coordinated with each other in the supply and demand of materials.Averaging control is used more and more widely in industrial production process.For design,operation and proportional integral differential(PID)parameters setting of averaging control system,a cascade averaging control system to control liquid level and flow is proposed after the study of control requirements of demethanation tower and deethane tower in deep condensate recovery unit.The selection principle of control law and the main points of putting the system into operation are introduced.The operation process and PID parameter setting process of the system are described in detail.The control effect is analyzed and summarized.The practical application shows that the cascade averaging control system balances the contradiction between the liquid level control and the flow control.Liquid level and flow of the demethanation tower and the deethane tower are controlled within the required ranges,and the change is gentle.The whole equipment runs continuously and smoothly after being put into operation successfully in one time.The system has the value of popularization and application in continuous industrial production process with similar series equipment.