NUMERICAL AND EXPERIMENTAL STUDY OF MIXTURE GRINDING OF MATERIALS WITH DIFFERENT STRENGTHS

Abstract

At joint grinding of components with different strength the particles of more strong material are of larger size than the particles of less strong material. The size classification of such mixture allows enriching the objective component in the end product. The scientifically grounded choice of technological conditions for effective separation of a mixture of materials of different strength is an actual problem for chemical and other industries. The computational research was done using the conception of chemical processes modeling based on the discrete analogues of the Boltzmann equation. A special program for experimentations and experimental data treatment obtained at a lab-scale fluidized bed jet mill was developed. A model to describe the grinding kinetics for each component of a mixture was developed. It allows estimating the efficiency of enrichment of the end product by the objective component. A method to solve the equations of the selective model of grinding and the computer algorithm for its realization was developed as well. The experimental data on grinding of binary mixture of components at their different content in the fluidized bed jet mill hold-up were obtained. These data were used to identify the model with respect to the parameters that characterized the grindability of each component. The model adequacy was checked using the data on joint grinding of mixtures with different content of components. These data were not used for the model identification. Comparison of calculated and experimental data showed the model adequacy and possibility of its usage to estimate the efficiency of components separation. The investigation allowed generalizing the conceptions of chemical processes modeling based on the discrete analogues of the Boltzmann equation to the case of selective grinding of a mixture of components with different strength. The computational analysis showed that the model allowed describing the process with acceptable for engineering practice accuracy, practical estimating the possibility of components enrichment and defining the optimal technological conditions for their separation.Forcitation:Zhukov V.P., Osipov D.А., Otwinowski H., Urbaniak D. Numerical and experimental study of mixture grinding of materials with different strengths. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 6. P. 109-115.