Driving Spray Drying towards Better Yield: Tackling a Problem That Sticks Around.

Powder deposition and accumulation on walls of spray drying chamber has been known to impact spray drying processes, resulting in lower yield, frequent shutdowns, and downtimes. Critical factors that impact the extent and rate of wall deposition have been studied extensively in the chemical and food industry. In this paper, we present an atypical process yield issue wherein acceptable yield is obtained during the first batch of spray drying but undergoes significant yield loss in consecutive batches.

Characterization of Spray Dried Particles Through Microstructural Imaging.

Spray drying is commonly used to produce amorphous solid dispersions (ASD) to improve the bioperformance of poorly water-soluble drugs. In this study, imaging techniques such as focused ion beam-scanning electron microscopy (FIB-SEM) and X-ray microcomputed tomography (XRCT) were used to study the microstructure of spray dried (SD) particles. Spray drying at higher outlet temperature (T) was found to produce more spherical hollow particles with smooth surface and thinner walls, while more raisin-like particles with thicker walls were generated at lower T.

Transport phenomena in chaotic laminar flows.

In many important chemical processes, the laminar flow regime is inescapable and defines the performance of reactors, separators, and analytical instruments. In the emerging field of microchemical process or lab-on-a-chip, this constraint is particularly rigid. Here, we review developments in the use of chaotic laminar flows to improve common transport processes in this regime.