(23b) Optimization of a Commercial-Scale Agrochemical Crystallization Prone to Oiling and Agglomeration

Solution crystallization is a common method for recovery and purification of agricultural active ingredients. To maximize the purity of the product and minimize processing challenges, oiling and agglomeration should be avoided during the crystallization step. This presentation describes the optimization of a commercial-scale agrochemical crystallization prone to oiling and agglomeration. Design-of-Experiment (DoE) principles were applied at lab scale to explore the impact of process variables on particle size distribution (PSD), filtration rate, and drying time. Observations from an in situ imaging probe (EasyViewer 400) revealed differences in primary particle size that were not discernible by laser-diffraction-based PSD measurement and that had a significant effect on drying rate. The on-line imaging probe also provided insight into oiling and agglomeration phenomena, prompting changes to the process that substantially improved the throughput and reliability of the commercial operation.