METHOD FOR OPTIMIZING JET MILL GRINDING CONDITION

PROBLEM TO BE SOLVED: To provide a method for efficiently and precisely setting jet mill grinding conditions for stably obtaining a powder having a specified grain size distribution. SOLUTION: First, a plurality of factors influencing a grinding process are selected, then a plurality of levels are selected for every selected factor and the selected factor and the selected level are allotted to an orthogonal arrangement table according to an experimental planning method, and the grain is test-ground in accordance with grinding conditions based on the orthogonal arrangement table. Further, the particle diameter (D50) which accounts for 50% of the integrated grain size distribution (volume standard) from the small particle diameter side of the obtained powder, and/or the particle diameter (D90) which accounts for 90% of the integrated grain size distribution (volume standard) from the small particle diameter side of the obtained powder, is measured. Then, the scatter analysis of the measurements is performed, then the promising factors to D50and/or D90are specified, and the point estimation and the interval estimation of D50and/or D90are carried out at each level of the specified promising factors. Further, the desired jet mill grinding conditions are decided according to the estimate and the confidence interval sought by the point estimation and the interval estimation. COPYRIGHT: (C)2011,JPO&INPIT