Mixing Effects in Continuous Free-Radical Solution Copolymerization Tank Reactors: Ⅰ-Characterization of Residence Time Distributions

摘要

The residence time distributions (RTDs) of continuous solution copolymerization tank reactors connected in series are evaluated experimentally to analyze features related to the fluid dynamics of this class of reactors. For this purpose, tracer step experiments are carried out in lab-scale polymerization tank reactors to provide experimental data for analysis of the quality of mixing and evaluate associated macromixing effects. Besides, mathematical models are developed to describe the RTD data obtained experimentally. Based on a compartmental approach, perfect mixing tanks, tanks with stagnant zones, tanks with crossflow, and tanks in series with backflow models were proposed. Particularly, the analysis of the available experimental data and of mathematical models indicate that the flow features of these systems are strongly associated with the established degree of mixing, presenting significant non-ideal flow behavior, usually neglected in most modeling and experimental studies.