Regularities in the distribution of granulometric composition of tuff while crushing

Abstract

Purpose is to analyze distribution of granulometric composition of tuff as well as ultimate composition and identify dependence of its softening in the process of water saturation based upon a set of experiments to assess raw materials importance of the mineral. Methods. Laboratory experiments were carried out to determine ultimate composition of tuff extracted from different open pits of the region. Methods of mathematical statistics were applied to derive analytical dependences describing the tuff softening in the process of water saturation. The dependences denote logarithmic nature of the saturation increase along with the increase in the sample weight. Findings. It has been determined that tuff is a valuable mineral rather than basalt extraction waste. Thus, tuff needs both mining and complex approaches for processing and extracting of useful metals and silicates. Analytical dependences of tuff softening during water saturation have been defined. The dependences denote logarithmic nature of the saturation increase based upon a sample weight increment. Magnetic susceptibility of tuff, turned on magnetic field induction, has been identified. Dependences of distribution of technological indices (i.e. product yield, copper content and yield) in terms of granulometric-size class have been identified; the basic factors for crushing process have been determined; and regression dependences of grinder efficiency upon the input factors have been derived. Regression model of a crushing process of a general technological scheme of ore processing has been obtained involving the initial fragmentation using a jaw crusher, and additional fragmentation (i.e. reduction) using a sizer. Originality.It has been determined that magnetic susceptible tuff share is 49% of the sample weight; the remaining part is a silicate share. Logarithmic nature of the analytical softening dependences while water saturating has been identified. The above-mentioned denotes the increased saturation along with the increase in a sample weight. Practical implications. The definition of tuff ultimate composition as well as analytical softening dependences in the process of water saturation makes it possible to calculate the required water consumption. Keywords: tuff, basalt, softening, water saturation, silicate, magnetic susceptibility, ultimate composition, crushing