净化液氮洗顺序控制联锁优化及应用

Optimization and Application of Sequential Control Interlock for Purified Liquid Nitrogen Washing

采用DCS控制系统PKS300对液氮洗分子筛进行了顺序控制。介绍了液氮洗主装置流程、吸附再生程序;根据系统的组态软件特点和相应功能顺序论述了分子筛顺序控制的过程和方法。本文以煤化工企业为研究,通过对在实际应用过程中,结合了工艺操作的实际经验,将DCS与安全仪表系统之间的串口通信优化为硬接点I/O输入输出方式,又进行顺控部序算法的优化,仪表异常状态下的故障退守模式,使得液氮洗顺控性能优化改造能以最佳状态适应整个生产系统。成功解决了影响装置非计划停车的问题,为其同行提供一些参考。

DCS control system PKS300 was used to control the sequence of liquid nitrogen washing molecular sieve.The process flow and adsorption procedure of liquid nitrogen washing are introduced.According to the characteristics of the configuration software of the system and the corresponding functional sequence,the process and method of molecular sieve sequence control are discussed.In this paper,taking coal chemical enterprises as the research object,the serial communication between DCS and safety instrument system is optimized as hard contact I/O input and output mode by combining the practical experience of process operation in the practical application process,and the sequential control algorithm is optimized,and the fault fallback mode in abnormal instrument state makes the optimization and transformation of sequential control performance of liquid nitrogen washing adapt to the whole production system in the best state.Successfully solved the problem that affected the unplanned shutdown of the plant,and provided some reference for its peers.