(270a) Development of an Automated Multi-Stage Continuous Reactive Crystallization System with in-Line Pats for High Viscosity Process

An automated multi-stage continuous reactive crystallization system with in-line PATs for a high viscosity process was developed in the present study. Data Acquisition (DAQ) hardware and Labview software were used as the local control system. A “forward-backward” burst pumping strategy was developed to smoothly transfer the highly viscous hot slurry from one vessel to the next. In addition, a comparative analysis between a PFR and CSTRs in series revealed that to achieve the same conversion, the latter would require more volume than the former, but less than a single CSTR. For a second-order reaction, the value of the Damkӧhler number necessary to achieve conversion of 90.0% in a single CSTR is 90. Thus, it is reasonable to approximate a PFR using CSTRs in series to obtain a high yield with a smaller reaction volume (compared with a single CSTR). In-line FBRM and React IR were used to monitor the crystal size and reactant concentration in the vessel containing cold slurry, as the probes could not be positioned in the hot slurry due to fouling issues. E-factors of batch and continuous processes were also compared, and the continuous reaction could obtain a lower E-factor because less waste was generated.