Symak D. Scientific and theoretical basis of mass transfer in systems with solid phase

The dissertation is devoted to theoretical and experimental researches of mass transfer processes with solid phase in two- and three-phase systems, which are the actual scientific and applied problem for processes of chemical technology. The solved scientific and technical problem enables to simulate mass transfer processes of drying, dissolution and extraction, to use new methods of their intensification and calculation of equipment for their implementation. Hydrodynamics, heat and mass transfer and the dynamics of filtration drying of dispersed materials were studied and the kinetic coefficients for the substances involved in the process were determined. Theoretically and experimentally was investigated the dissolution of polydisperse mixtures in a periodic action apparatus under conditions of change in motive force. Experimentally was investigated the continuous direct solubility of a stationary granular layer in a vertical apparatus and determined the concentrations at certain heights of a layer. A mathematical model of the dissolution process is made and its solution is presented. The theoretical algorithm for calculating of concentrations and dimensionless diameter is presented. Effective diffusion coefficients were determined and was shown the possibility of increasing of the extraction rate up to 6 times compared to the external mechanical mixing of medium. The theory of the mass transfer process in the three-phase gas-liquid-solid system was developed, and each mass transfer stage was studied: physical absorption, mass deduction, diffusion-controlled chemical dissolution. The mathematical models of the non-stationary heat transfer process with a superficial heat source are developed, which allows to determine the temperature in solids and liquid media. An analogy of heat transfer and mass transfer is shown, which is determined by the same hydrodynamic situation in the reaction zone. For the industrial solvent a mathematical model for dissolving potassium salt is developed. The technological scheme of purification of gas medium from sulphur dioxide in a three-phase system is proposed on the basis of conducted researches.