The Application And Study Of DeltaV DCS In Homogenous Polymerization Propene

With the distributed control system (DCS) application and development, to develop and apply a simple, safe, reliable and easy to use or control program has become true. DeltaV DCS system inherited PROVOX DCS and RS-3 DCS system advantages, using fully the latest technologies of computers, networking, digital communications, graphic designs and control strategy, combining with workstations, ethernet, digital buses, OPC, XML and other advanced technologies. All of them provided users with a simple, flexible software and hardware installation, convenient configuration and more precise control.This topic came from propylene homogeneous polymerization system improvement project of Lan Gang Company. The control system was built in 1995, and used the U.S. Fisher-Rosemount company's RS-3 DCS systems. With the development of propylene homogeneous polymerization industry, it required highly for product quality and craft control systems. However, the RS-3 DCS system was not able to upgrade, and the control technology was relatively backward, which brought lots of problems, such as frequent hardware failures, few original cards and other pieces of hardware manufacturers, low level automation control devices, a too simple control strategy. Moreover, the current control system was short of accuracy, openness, advancement and normalization. This paper developed an advanced propylene homogeneous polymerization control system, which based on the DeltaV DCS system, and combined with configuration software, industrial ethernet, PROFIBUS and other advanced industrial control technologies and strategies. It achieved advancement, openness and reliability requirements for DCS control process.The paper discussed the development status, trends and prospects of polypropylene and DCS. The problems of the common DCS also presented. Nowadays, the world and China's polypropylene markets are all placed in the situation of demand exceeding supply. DCS in producting polypropylene develops in universal computer, ethernet network, distribution, intelligence and fieldbus continuously since the DCS emerged. But the common DCS has some problems.In the part of DeltaV DCS System, the paper introduced the system architecture, system control network, control network security, system composition and function descriptions and so on in detail in eight parts. It showed that the DeltaV DCS system characterizations, such as variable size, online upgrade support, redundant control design, off-line configuration and so on.In the part of propylene homogeneous polymerization system control design, the paper discussed the system process and designed it control strategy.In the control strategy achievement part, the paper introduced briefly the DeltaV DCS system control structure of propylene homogeneous polymerization system. It discussed the system functions and control algorithms of basic functions blocks, and expounded the function of propylene homogeneous polymerization system, such as basic measurement parameters, general PID control, complex loop control, sequential function control and PID control strategy.The DeltaV DCS system propylene homogeneous polymerization system has been put into use since October 2009. The entire control system was running smoothly, operating easily, and man-machine interface was friendly. Its successful application had advancements for applying PlantWeb, AMS, OPC, Ethernet, and other advanced industrial technologies in domestic large-scale petrochemical enterprises.