浅谈聚丙烯装置中PDS控制系统的设计

Brief Discussion on PDS Control System Design in Polypropylene Plant

产品卸料系统(PDS)的稳定性与可靠性直接影响到聚丙烯产品的产率。简要介绍了采用UNIPOL工艺生产聚丙烯装置中PDS的流程及其特点;阐述了PDS控制系统的组成、PLC硬件的选型、PLC软件的设计、PDS阀门的选型与设计、顺序控制和联锁逻辑的设计,并详细描述了顺序控制逻辑的步骤、顺序控制时间的设定、顺序控制终止与联锁逻辑保护等相关的设计要点,从而为同类型聚丙烯装置中PDS控制系统的设计提供了思路与参考。

Production yield of polypropylene is directly affected by the stability and reliability of product discharge system（PDS）. The process and its characteristics of PDS in polypropylene installation with UNIPOL process are briefly introduced. PDS control system composition, PLC hardware type selection, PLC software design, type selection and design of PDS valve, sequence control and interlocking logic design are expounded. Relative key design points of steps of sequence control logic, sequence control time setting, sequence control termination and interlock logic protection etc. are described in detail. The thinking and reference for PDS control system design for same type of polypropylene installation are provided.