ABSTRACT
This chapter considers the basic laws of convective and diffusion mass transfer, the determination of the coefficients of molecular, Knudsen and turbulent diffusion, the calculations of the one-dimensional diffusion, and Stefan flows and the character of the equimolar and non-equimolar mass transfers and the consequences arising from them. The coefficient of turbulent diffusion is a function of stream turbulent properties, cross coordinate, and also depends on coefficient of molecular diffusion, physical properties of the environment and, in some problems of a mass transfer, on the concentration of any component. In devices to the big thickness of a layer of particles, there is a consolidation of a layer under the influence of the external deforming forces and a body weight of a layer over time that significantly influences transfer coefficients. Consolidation of a layer of particles is characterized by generally technological devices with a motionless layer of the catalyst, adsorbent, and other particles fillers.
