Monte Carlo modeling of particle agglomeration during polymer pyrolysis in bubbling fluidized bed

During the bubbling fluidized bed polymer pyrolysis process, the agglomeration of inert materials frequently leads to defluidization. To simulate this phenomenon, a novel time-driven Monte Carlo model is presented, which comprises two main stages: the layering period and the agglomeration period. The simulation results are then compared with experimental data from literature. From a qualitative analysis perspective, the simulation results effectively replicate the trends in defluidization times under various operating conditions. In terms of quantitative analysis, the predicted defluidization times exhibit a good consistency with the measured values (R2=0.804). Furthermore, information extracted from the simulation, which is hard to obtain experimentally, is applied for further discussion. It allows to explore the composition of bed materials at the defluidization moment under different operating conditions. Additionally, a comparison of particle size distributions at same operational time under various operating conditions is performed. In general, the developed model provides a robust foundation for extending its application to other polymer pyrolysis processes as well as co-pyrolysis processes.