Temperature control of a highly active catalyst polyolefin polymerization reactor at an unstable operating point

摘要

The invention of a new catalyst, Metallocenes, which is highly active, selective and able to control polymer structure more precisely than the ordinary catalyst, leads the polyolefin polymer production to a new catalyst revolution. However, because the catalyst is sensitive to temperature, it pushes the plant to operate at an open-loop unstable point. This paper deals with a design problem of temperature controller for an industrial polypropylene polymerization reactor, which is open-loop unstable when the new catalyst is used. The dynamics of the open-loop unstable process is identified by a first order system with integral and dead time element. Then, the controller is realized in an I-PD structure. The application result illustrates that the developed controller can successfully stabilize the plant.