Continuum Approach to Optimizing Downstream Final Drying with Upstream Solid-Liquid Separation

This presentation will review the optimization of the selection of the final drying technology in conjunction with the upstream continuous solid-liquid filtration, cake washing, and dewatering technology selection. Most often when analyzing a new process development approach, engineers take a “silo” approach and look at each step independently. This presentation illustrates that by taking a holistic approach and looking at each step not individually but as a continuum, the process solution becomes much more efficient. Data is presented showing how to balance each of process steps for maximum efficiency.

In the manufacturing of this specialty chemical, the crystals coming from the reactor in a methanol slurry must be filtered, washed and dewatered and then dried to a final moisture of less than 1.0 (<1.0 %). The standard approach would be to first look at the solid-liquid filtration step and optimize this step for the maximum washing and drying efficiency and then with this information optimize the downstream drying. The operating company, however, took a different approach and looked at the process as a continuum from solid-liquid filtration through cake washing and dewatering to final drying. The Continuum Approach” resulted in operational energy and nitrogen savings as well as lower capital and installation costs for a more efficient and reliable process.

The overall approach illustrates a methodology for an optimization approach that can be used by engineers for chemical and pharmaceutical applications.