Application of pulsed spray and moisture content control strategies on quality consistency control in fluidized bed granulation: A comparative study

A quality consistency control study on a fluidized bed granulation (FBG) was carried out with the introduction of pulsed spray and moisture content feedback control methods. Near-infrared spectroscopy (NIRS) was used non-invasively for in-line quantitation of the critical quality attributes (CQAs) of granules. A self-adjusting fuzzy-PID controller was developed and applied in the FBG process. The performance of these strategies on the quality consistency control was examined. Both similarity and principal component analysis (PCA) were employed to evaluate the quality consistency of granules produced by these methods. The relative standard deviation (RSD) of the CQAs of granules produced by pulsed spray and moisture content control strategies were less than 5%, while the conventional method was more than 5%. The results demonstrated that the moisture content feedback control strategy offers a powerful way to increase the quality of final granules, and simplifies the quality consistency control by stabilizing important quality attributes.