抄録
The grading technology with crushing and grinding is necessary to produce materials like natural river sands and to obtain sub-micron powders for the materials for electronic devices and surface lining. It is known that grinding operation is the representative method, and it may be possible to grade particles. But in the field of grading particles, it is not common to study the grading phenomena in the process of grinding by the time, especially to study the particle size distribution of coarse powder in the closed circuit grinding system. Based on the analogy of sieving model by the Information theory, this paper led to the result by the time dependence equation in the grinding process, and it showed that the obtained equation has similarity to that of grinding Matrix. Moreover, the grading mechanism of the sands was figured out by verifying the equation of the closed circuit grinding system, using Onuma's data and graded sands or booming sands. And also, the paper suggests that applying another technology is very effective to save energy at the point that the transfer from volume grinding to surface grinding had occurred. And the examination of the materials could be useful in making a plan to produce the range of the particle size.
