AN EVALUATION OF PROCESS VARIABLES IN WET GRANULATION

In wet granulation, determining the process variables which play an es sential role in granule quality is crucial for optimizing the manufact uring process. An L16(2(5)) fractional factorial experimental design u sing the table of orthogonal arrays was employed in order to estimate the relative intensity of the influences of five process variables on granule quality in wet granulation using a high-speed mixer granulator . Total volume and formulation of binder solution, blade rotation spee d, granulation time, and amount of powder supplied into the granulator were selected as decisive process variables in the formation of granu les. Granule yield, geometrical mean granule size and uniformity of gr anule size were evaluated as representative properties of granule qual ity. Experimental results were analyzed according to the analysis of v ariance (ANOVA). The results of significance test and contribution rat io in ANOVA indicated that, within the experimental region, only binde r solution had a critical effect on the three physical properties of t he obtained granules. The effects of other variables were found to be minimal. Further, the contribution of sampling error to total variance was quite small.