PRODUCT QUALITY ATTAINMENT IN GRANULATION PROCESS
Granular products made from pan granulation processes are typically characterized by their particle size distributions (and bulk densities). Material produced in a particular month at a manufacturing site has a particle size distribution that is well-characterized by a lognormal dis- tribution with scale parameter α = 6.8 and shape parameter β = 0.5, i.e. X ∼ L(6.8, 0.5). The product quality requirements (in microns) is
speci?ed as 350 μm X 1650 μm, and the yield of the process is the percentage of the product meeting this requirement. To be pro?table, the manufacturing process yield must be at least 85% month-to-month.
(i) What is this month's process yield?
(ii) If particles for which X <>350 μm are classi?ed as "?nes" and can be recycled, how much of the material made during this month falls into this category?