Research of operational parameters of the centrifugal module during rock mass processing

Abstract

This article presents research of the operating parameters of a centrifugal disintegrating module when processing rock mass. It consists of determining the dependence of the material degree of crushing on the rock mass characteristics and the disintegrator operational parameters, using a physical research method. At the initial stage, the percentage distribution of particle size classes of the material after grinding was established. It confirmed the feasibility of using an additional screening surface in the form of a mesh, which significantly affects the increase in the percentage yield of small classes of crushed material, namely classes -160 and –100 microns. It can be explained by the continuous screening of the finished material product, which helps to improve the grinding process by eliminating the effect of volumetric compression of the material. It was found, that the use of vibration when using a mesh is mandatory, since the presence of vibration from the rotation of the rotors and the movement of air inside the grinding chamber were insufficient for fine material screening. The main part of the research was to establish the nature of degree of the material grinding dependence on three types of raw materials differing in strength and initial size, as well as the amplitude of vibrations of the screening surface. It was determined, that the stronger is the source material, the lower is degree of its grinding. But it should be taken into consideration, that for many natural materials, with increasing of their strength, their fragility also increases, which improves grinding performance. Also, the larger pieces of material are loaded into the disintegrating module, the greater is degree of its grinding. It is explained by the peculiarity of the operation of centrifugal disintegrators, which use centrifugal forces to accelerate a piece of material with its subsequent impact on the lining or oncoming flow of material, with the most optimal initial size of the material, for the given dimensions and operating parameters of the centrifugal disintegrating module, is within the range ∆ = 7–9 mm. It was established that an increase within acceptable limits in the amplitude of vibrations of the screening surface leads to an increase in the degree of grinding. In general, the conducted research confirmed the prospects of using a centrifugal disintegrating module at the last stages of fine grinding in order to reduce energy costs and increase the grinding fineness of rock mass. Keywords: rock mass, grinding, disintegrator, degree of grinding, vibration.