COMPUTATIONAL AND EXPERIMENTAL STUDY OF JOINT GRINDING OF DISSIMILAR COMPONENTS IN A CIRCULATING FLUIDIZED BED JET MILL

Abstract

At joint grinding, classification and mixing of dissimilar particulate solids, not only the total content of each in a mixture is the point of researcher’s interest but also the particle size distribution in each component. It is particularly important for enrichment and purification of components at their joint grinding and classification. Tracers of different type (radioactive, colored, etc.) are commonly used for this purpose. However, such methods are available not for any materials due to technological, financial and sanitary limitations. An alternative simple and easy available approach to investigate the particle size distributions in a mixture is proposed. It is based on application of soluble tracers and can be used in the case of selective solution of one of the components in a chosen solvent. Such method to define the particle size distribution can be interesting for the chemical and other industries. A laboratory impact mill was used for experimentation and identification of the model of joint grinding of a components mixture. This part of the research allowed obtaining and testing the method to define the particle size distributions in the binary mixture of components one of which was solvable in water, and another one was not. The developed method was used for grinding kinetics of joint grinding of two dissimilar components. The conducted research allowed developing a conception of modeling of the selective grinding of dissimilar components mixture. The computational analysis showed that the proposed model with calibrating parameters obtained from the experiments allows describing the process of selective grinding of a dissimilar components mixture with the accuracy that is acceptable for engineering practice. It allows using the model for practical estimation of the objective components enrichment and defining the optimal conditions for dissimilar components separation.