SU1681953A1 - Method of comminuting materials in drum-type mill - Google Patents

Abstract

The invention relates to the grinding of ores and can be used in the mining industry. The purpose of the invention is to increase the efficiency of the grinding process by increasing the total dynamic activity of the ball load. This goal is achieved due to the fact that the ratio of the duration of grinding in waterfall and cascade modes is gradually reduced in the direction of the discharge of the mill. 1 hp ff, 6 ill.

Description

The invention relates to the field of grinding ores and can be used in the mining industry.

The purpose of the invention is to increase the efficiency of the grinding process by increasing the total dynamic activity of the ball load.

According to the method of grinding materials in a drum mill by using the energy of grinding bodies operating in waterfall and cascade modes, the ratio of the duration of grinding in waterfall and cascade modes is reduced towards the discharge of the mill.

FIG. 1-5 are schematic sections of drums along the length of the mill; in fig. 6 - scan of the mill drum.

The lining on the mill drum is laid in rings. In the first ring at the boot end of the mill, almost all the plates are wavy. Then the number of corrugated plates decreases, and the number of smooth plates increases. At the discharge end of the mill, all lining pligs are smooth.

The source material enters the bar- 1 ban mill. At the beginning of shredded

the chambers are dominated by wavy lining plates, so the material is ground during the waterfall mode. As material progresses along the mill drum, the time it takes to grind material in a waterfall mode decreases. As the material approaches the discharge end, it is mainly affected by abrasive loads and at the discharge end only abrasive loads act on the material. The milled material is removed from the mill.

The method was carried out on an MSR 45 x 50 ball mill. For grinding, a material with a size of 25-0 mm was taken. The lining on the drum was packed with rings of smooth and wavy lining plates (Fig. 6).

In the first row, 6 wavy lining plates and 2 smooth lining plates were installed (Fig. 1), 5 wavy lining plates and 3 smooth lining plates (Fig. 2) were installed in the second row, 4 wavy and 4 smooth ones were installed in the third row lining plates (Fig. 3), in the fourth row - 2 wavy and 6 smooth lining plates (Fig. 4), in the fifth set 8 smooth

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hitch lining plates (Fig. 5). This ensured the work of the grinding load in the waterfall and cascade modes, while the ratio of the grinding time in the waterfall and cascade modes decreased in the direction of unloading and the cascade mode was set at the discharge end. A material with a particle size of 12–0 mm was removed from the mill.

The experimentally determined limits of the ratio of the duration of grinding in waterfall and cascade modes are given in the table.

As follows from the table, the most optimal is a gradual decrease in the ratio of the duration of grinding in waterfall and cascade modes towards the discharge of the mill from 3 to 0. With such a change in the ratio of grinding modes, the highest productivity of the mill in the finished grade of 0.074 mm is observed.

In the method of zd, by reducing the ratio of the duration of grinding in waterfall and cascade modes and at the discharge end of the drum a cascade mode is established, the mode of operation of the grinding bodies along the length of the drum changes. It provides shredding of large classes.

material crushing loads. As the material progresses towards the discharge end, the material is crushed for longer times under abrasive loads. At the discharge end, where the size of the material is minimal, the material is subjected only to abrasive loads of grinding bodies. Due to this, the grinding efficiency is significantly increased compared with the known method.

Claims (2)

1. A method of grinding materials in a drum mill by using the energy of grinding bodies operating in waterfall and cascade modes, characterized in that, in order to increase the efficiency of the grinding process by increasing the total dynamic activity of the ball load, the ratio of the grinding time in waterfall and cascade modes gradually reduce the discharge of the mill. 2. The method according to claim 1, from l and h with the fact that the ratio of the duration of grinding in waterfall and cascade modes varies from 3 to 0. The change in grinding efficiency when changing the ratio of the duration of grinding in waterfall and cascade modes (according to the class content of 0.074 mm in the discharge of the mill) Ajf2. -i FIG. 2 cpua.3 .four F “g. $ FIG. 6