Modeling of particle segregation phenomena in a gas phase %uidized bed ole)n polymerization reactor

In a gas phase %uidized bed ole)n polymerization reactor, it is generally assumed that polymer particles are well mixed and near isothermal reaction conditions prevail. When a highly active Ziegler–Natta catalyst or other type of high activity supported catalyst is used in a gas phase %uidized bed reactor, a certain heterogeneity in the polymer properties is often observed in di4erent size particles. Moreover, particle agglomeration and sheeting phenomena may also occur due to irregular particle growth, internal particle segregation or nonisothermal e4ect. In many of the past reports, particle residence time distribution has been commonly used as a tool to calculate polymer particle size distribution in a %uidized bed polyole)n reactor. In this paper, a multi-compartment population balance model is presented to directly model the particle segregation phenomena and particle size distribution in a gas phase ole)n polymerization reactor. To model the particle segregation e4ects, size dependent particle transfer constants are employed. The e4ects of various %uidized bed operating conditions on the particle size distribution are investigated through model simulations. ? 2001 Elsevier Science Ltd. All rights reserved.