Control of Polyethylene Properties using Nonlinear Model Predictive Control
نویسندگان
چکیده
Abstract: This paper deals with the control of the melt index and density of polymers produced. Nonlinear Model predictive control (NLMPC) is used for this purpose. A nonlinear reactor model combined with correlations for predicting polymer melt index and density are used to simulate the process. The simulations revealed the effectiveness of NLMPC to drive the polymer properties to follow a series of grade changeover in the absences and presence of modeling errors. Grade transition is achieved with zero offset but with relatively large settling time. Rapid grade changeover is limited by the large residence time and broad residence time distributions for both the gas phase and formed polymers.
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