| 摘要 |
PCT No. PCT/FR97/00492 Sec. 371 Date Sep. 21, 1998 Sec. 102(e) Date Sep. 21, 1998 PCT Filed Mar. 20, 1997 PCT Pub. No. WO97/35665 PCT Pub. Date Oct. 2, 1997A continuously operating process and a plant for comminuting by grinding a mineral material into grains of different sizes and dividing the ground product into several fractions each constituted by grains the dimensions of which are between a predetermined upper limit and a predetermined lower limit. Starting from a raw product, it is subjected to grinding by material layer crushing, the ground products are divided into several fractions comprising at least one coarse fraction and one fine fraction, and those grains the dimensions of which are greater than the upper limit of the coarse fraction, and possibly all or part of the fractions the grains of which have dimensions between the lower limit of the coarse fraction and the upper limit of the fine fraction, are returned to the grinder input. |
