Determination of the mass transport in the polycondensation of polyethyleneterephthalate by nonlinear estimation techniques

摘要

The reaction rate of the polycondensation of polyethyleneterephthalate in the melt is determined by the mass transfer of the reaction product ethyleneglycol from the melt into the gas phase. This mass transfer is described by the product of the mass transfer coefficient and the specific surface. Its knowledge offers new possibilities in process control. We developed three different nonlinear parameter estimators based on a simplified model of the process which were all implemented in a process control system. The optimization based approach exhibited the best robustness and therefore should be preferred for online application. The estimation results are compared to experimental data.