Simulation of Ion-Exchange Filtration of a Liquid, Taking into Account the Process of Clogging and Suffusion

Abstract

In the research work, an urgent problem is solved related to the technological process of filtering and dehydrating liquid solutions from fine impurities and particles, as well as from unwanted ionic compounds. For the development of a mathematical model of the technological process, research works for the last 10-15 years related to the object of study were analyzed, on the basis of which a mathematical model and a stable numerical algorithm were developed for conducting a computational experiment on a computer. When developing a mathematical model of the technological process, the main factors and parameters that significantly affect the object of study are taken into account, and special attention is paid to the process of clogging and suffusion in a porous medium.

The work solves the problem associated with the determination of the main parameters and their ranges of change in the process, leading to an increase in the performance of the filters used, a decrease in the loss of valuable raw materials and an improvement in the quality of the resulting output product. Based on the analysis of the conducted numerical experiments, conclusions are formulated that serve as the basis for making appropriate management decisions.

Numerical calculations have established that: due to the clogging of gel particles in the pores of the filter and the formation of a sediment layer on the surface of the filter column of the unit, the rate of suspension filtration decreases with time; when filtering a suspension, the intensity of the liquid supply to the column of the unit, the thickness of the partition and the initial porosity of the filter play a significant role; an increase in the rate of liquid supply to the filter column in the initial stages of the filtration process will lead to an increase in filter performance, and then, due to the clogging process, the switching time of the filter unit is reduced and the hydraulic pressure in the filter increases; with an increase in the baradiffusion coefficient, the rate of change of exchanging ions in the solution and the filter partition increases, and the maximum saturation of its filter pores with ions and gel particles will occur in the upper layers of the filter partition, and the filter operation time increases with an increase in the size of the gel particles in the solution.