Stirring type ball mill

Abstract

The invention relates to a stirring type ball mill. The ball mill includes a milling chamber having a cylindrical wall. The ball mill also has a rotatably mounted agitator shaft extending into the grinding chamber on which at least one agitator element is arranged inside the grinding chamber. The ball mill further comprises an inlet for supplying the material to be ground and the grinding body to the grinding chamber and an outlet for removing the ground material. The grinder also has an induction heater for the material to be ground located in the grinding chamber, the induction heater comprising an inductor and a susceptor. The at least one stirrer element comprises a susceptor material forming a susceptor of the induction heater, where the inductor comprises at least one coil arranged outside the cylindrical wall of the grinding chamber and surrounding the grinding chamber, where the cylindrical wall of the grinding chamber is made of a non-conductive, non-magnetic material.

Description

technical field [0001] The invention relates to a stirring ball mill. Background technique [0002] A known agitated ball mill is described, for example, in EP 3102332 B1. The agitated ball mill described therein comprises a substantially cylindrical grinding chamber and a rotatably mounted agitator shaft, the grinding chamber being bounded by a cylindrical wall and inlet-side and outlet-side end walls, in which The stirrer elements (also called accelerators) on the stirrer shaft are arranged axially (ie, in the direction of the longitudinal axis of the stirrer shaft) inside the grinding chamber spaced apart from each other. In the vicinity of the inlet-side end wall, an inlet for supplying the material to be ground and the grinding body is arranged, and in the outlet-side end wall, an outlet for removing the grinding material is provided through a separator that holds or blocks the grinding body The screen is separate from the grinding chamber. During operation, the agit...

AI Technical Summary

Problems solved by technology

However, the arrangement described in WO 2019 / 228983 A1 also has disadvantages

On the one hand, in the case of agitated ball mills with grinding chambers of small diameter, it is difficult or even impossible to accommodate relatively large induction coils on the agitator shaft due to lack of space

On the other hand, in the case of stirred ball mills with grinding chambers of relatively large diameter, the efficiency of the induction heater decreases, firstly because the induction heating of the stirrer elements increases with the radial distance of the stirrer elements from the inductor coil and secondly because during the grinding operation the material to be ground is mainly located in the peripheral area of ​​the grinding chamber

However, regardless of the size of the agitator ball mill, another problem is supplying power to the inductor coils that rotate with the high-speed agitator shaft

Another difficulty is that protecting the inductor coil from the erosion / abrasion action of the grinding body is complex

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