DEVELOPMENT, MODELING AND EVALUATION OF A (LAMINAR) ENTRAINED FLOW REACTOR FOR THE DETERMINATION OF THE PYROLYSIS KINETICS OF POLYMERS

Laminar Entrained Flow Reactors were examined to determine whether thi s type of reactor can be used to measure the kinetic parameters of the pyrolysis reaction of polymers. In case the EFR was operated in the t urbulent regime or the diameter of the reactor was to small, sticking of polymer to the reactor wall, became a major problem. In the laminar flow regime this problem did not occur and this operation regime was determined as a function of the Reynolds number. Due to the necessity of operation in the laminar regime significant temperature and velocit y gradients exist in the EFR. To correct for these gradients a model w as developed incorporating the Navier - Stokes equations to describe t he gas phase velocity and temperature distributions and a single parti cle model to describe the conversion of the individual particles. Whil e correction of the experimental data for the axial gradients proved t o be possible, it was not possible to correct this data for radial gra dients in the reactor due to the uncertainty in the radial position of the particle. Experiments were performed and corrected for the aforem entioned gradients to obtain the first order kinetic parameters for th e pyrolysis of LDPE. However, these parameters are inaccurate and ther efore a LEER is preferably not to be used to determine kinetics of par ticles, if operation of the EFR in the laminar regime is necessary (st icking particles). If possible (non sticking particles) the EFR should be operated in the turbulent regime. Finally our pyrolysis experiment s of LDPE showed that intermediate wax - like products are produced du ring the pyrolysis reaction, which are pyrolysed further in the gas ph ase.