Determination of the clogging time for continuous emulsion copolymerization in a tubular reactor using distributed optical fiber sensors

Abstract

A non-intrusive method for fouling monitoring using DOFS (Distributed Optical Fiber Sensors) in tubular reactors is presented. The hot spot, caused by the exothermal emulsion polymerization reaction of vinyl acetate and vinyl neodecanoate, was used as a marker to track the fouling progression during the reaction. Due to fouling, the reactor volume was constricted, causing the hot spot to migrate further downstream. This migration was spatially and temporally resolved as a hot spot position-time plot and used describe the time of clogging using mathematical models. From these models, it could be deduced, that the fouling influencing the hot spot is best described by an even constriction of the entire tubular reactor. The mathematical model was able to determine the time of clogging with an accuracy of 0.89–1.28 (with 1 being in perfect agreement with the measured clogging time), starting from 30 min of reaction time. This time is equivalent to 12 % of the entire time of reaction from start to clogging.