Effect of monomer feed and production rate on the control of molecular weight distribution of polyethylene in gas phase reactors

被引：13

作者：

Ali, Mohammad Al-haj ^{[1
]}

Ali, Emad M. ^{[1
]}

机构：

[1] King Saud Univ, Dept Chem Engn, Riyadh 11421, Saudi Arabia

来源：

COMPUTERS & CHEMICAL ENGINEERING | 2011年 / 35卷 / 11期

关键词：

Molecular weight distribution; Nonlinear model predictive control; Polymerization reactor control; Polyethylene; Fluidized-bed reactor; GRADE TRANSITION CONTROL; POLYMERIZATION REACTORS; OPTIMIZATION; CATALYSTS; ETHYLENE; COPOLYMERIZATION; SELECTION; MODEL;

D O I：

10.1016/j.compchemeng.2011.04.014

中图分类号：

TP39 [计算机的应用];

学科分类号：

081203 ; 0835 ;

摘要：

The control of the polymer molecular weight distribution via altering the monomer to hydrogen molar ratio in fluidized bed reactors is examined. The molar ratio is altered by manipulating the monomer and hydrogen feed rates using nonlinear model predictive controller. The simulation revealed promising results however a trade-off between utilizing both the monomer and hydrogen flows simultaneously and the hydrogen flow exclusively exists. Utilization of the monomer and hydrogen flows together favors the rapid transition to the required MWD but at the expense of higher purge and inconsistent production rate. Exclusive use of the hydrogen intake leads to steady production rate and less consumption of the purge. However, longer time is needed to achieve the desired MWD. The same phenomena are observed when discrete mechanism for product withdrawal is implemented. (C) 2011 Elsevier Ltd. All rights reserved.

引用

页码：2480 / 2490

页数：11

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