Mathematical Model of Mass Transfer in Randomly Packed Columns with Phase Maldistribution

Resumo

The paper considers the processes of mass transfer between phases in countercurrents of gas and liquid in stationary packed beds of industrial randomly packed column apparatus. Such beds are widely used in heat and mass transfer, separation, and reaction processes in the oil and gas processing, petrochemistry, and other industries. An approximate approach of mathematical modeling of mass transfer in a randomly packed bed at turbulent gas motion and countercurrent laminar wave flow of liquid film is analyzed. The basic concepts of the multispeed continuum model, in which the transfer equations are written for each phase separately, are used. The phases fill one space, the volume of the continuous phase (gas) exceeding by far that of the liquid one. The interaction of the phases is reflected in averaged transfer terms, which take into account the interfacial transfer phenomena. Those are the mass transfer coefficients and the driving forces of the processes. The concentration profiles of the components are found from the solution to differential mass transfer equations written for a cylindrical channel with a volume source of mass. This approach can be used in the absence of experimental data on the structure of gas and liquid flows in a packed bed, for example, when designing new contact elements.