Dynamics and Predictive Control of Gas Phase Propylene Polymerization in Fluidized Bed Reactors  

作　　者：Ahmad Shamiri Mohamed azlan Hussain Farouq sabri Mjalli Navid Mostoufi Seyedahmad Hajimolana~ 

机构地区：[1]Department of Chemical Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia [2]Training Center, Razi Petrochemical-Company, Bandar Imam 161, Iran [3]UM Power Energy Dedicated Advanced Centre (UMPEDAC), University of Malaya, Kuala Lumpur 50603, Malaysia [4]Petroleum and Chemical Engineering Department, Sultan Qaboos University, Muscat 123, Oman [5]Process Design and Simulation Research Center, School of Chemical Engineering, College of Engineering, University of Tehran, Tehran 11155/4563, Iran

出　　处：《Chinese Journal of Chemical Engineering》2013年第9期1015-1029,共15页中国化学工程学报（英文版）

基　　金：Supported by the Research Grants of the Research Council of Malaya

摘　　要：A two-phase dynamic model, describing gas phase propylene polymerization in a fluidized bed reactor, was used to explore the dynamic behavior and process control of the polypropylene production rate and reactor temperature. The open loop analysis revealed the nonlinear behavior of the polypropylene fluidized bed reactor, jus- tifying the use of an advanced control algorithm for efficient control of the process variables. In this case, a central- ized model predictive control （MPC） technique was implemented to control the polypropylene production rate and reactor temperature by manipulating the catalyst feed rate and cooling water flow rate respectively. The corre- sponding MPC controller was able to track changes in the setpoint smoothly for the reactor temperature and pro- duction rate while the setpoint tracking of the conventional proportional-integral （PI） controller was oscillatory with overshoots and obvious interaction between the reactor temperature and production rate loops. The MPC was able to produce controller moves which not only were well within the specified input constraints for both control vari- ables, but also non-aggressive and sufficiently smooth for practical implementations. Furthermore, the closed loop dynamic simulations indicated that the speed of rejecting the process disturbances for the MPC controller were also acceotable for both controlled variables.A two-phase dynamic model,describing gas phase propylene polymerization in a fluidized bed reactor,was used to explore the dynamic behavior and process control of the polypropylene production rate and reactor temperature.The open loop analysis revealed the nonlinear behavior of the polypropylene fluidized bed reactor,justifying the use of an advanced control algorithm for efficient control of the process variables.In this case,a centralized model predictive control(MPC) technique was implemented to control the polypropylene production rate and reactor temperature by manipulating the catalyst feed rate and cooling water flow rate respectively.The corresponding MPC controller was able to track changes in the setpoint smoothly for the reactor temperature and production rate while the setpoint tracking of the conventional proportional-integral(PI) controller was oscillatory with overshoots and obvious interaction between the reactor temperature and production rate loops.The MPC was able to produce controller moves which not only were well within the specified input constraints for both control variables,but also non-aggressive and sufficiently smooth for practical implementations.Furthermore,the closed loop dynamic simulations indicated that the speed of rejecting the process disturbances for the MPC controller were also acceptable for both controlled variables.

关 键 词：model predictive control fluidized bed reactor propylene polymerization Ziegler-Natta catalyst 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置] TQ051.13[自动化与计算机技术—控制科学与工程]