Case Study:  Debottlenecking a Solid Liquid Isolation: Laboratory to Capital Project

This work is a case study in the development efforts required to effectively de-bottleneck a bulk API intermediate manufacturing process. The goal was to increase process capacity within the constraints of quality, timeline, manufacturing footprint space and capital constraints. The existing solid-liquid isolation step was originally done using a batch centrifuge that was shared with a subsequent step in the process. Development work was done to optimize the upstream crystallization step to improve performance of current operations and create the necessary critical physical property data and filtration mechanisms to drive the selection process to identify the best technology. This work identified the indexing belt filter as the best technology. A pilot study was done with an indexing belt filter to verify proof of concept. This work revealed significant cake cracking occurred, resulting in non-uniform deliquoring and cake washing that led to the degradation quality of the isolate solids. Further development work was required to identify the necessary conditions required to avoid cake cracking. A second round of pilot studies was done on a larger scale that provided both proof of the generation of quality wet cake and the necessary design data for large scale purchase. The end result is the generation of a new isolation process, a semi- continuous filtration that increased capacity 84%, created less handling and better upstream and downstream process flow.