Physical modeling in water treatment technologies

Abstract

In most cases, water pollution is associated with the presence in it of a dispersed phase of various substances, which, depending on its physical state, forms various polydisperse heterogeneous aggregate-unstable systems: suspensions, emulsions, and foams. The paper analyzes the application of physical models for the description of complex dispersed systems, analyzes the possibilities of classic modeling methods and the limits of the application of the considered models. The paper studies the influence of temperature changes (of seasonal or climatic origin) on the kinetics of gravitational sedimentation in wastewater treatment technologies. Considered models of physical processes accompanying the gravitational deposition of dispersed particles in hydromechanical sedimentation tanks, which take into account the Brownian motion of these particles, capable, as it turns out, of causing coagulation. And coagulation makes it possible to transfer pollutants into a state of dispersed phase with a larger particle size. Within the framework of the considered model, it was established that the time and speed of particle sedimentation in gravity sedimentation systems may change significantly with external temperature changes. Accordingly, the quality of cleaning in a sedimentation plant, which works on the principle of gravity, can significantly increase (when heated from the outside) or decrease (when cooled). Thus, the need to take into account temperature changes in the processes of gravitational sedimentation of particles in treatment facilities is an urgent task. The paper concluded that in order to improve the existing technologies of water purification in the conditions of a change in external conditions (temperature), combinations of purification methods are appropriate for better water purification. In particular, the method of gravity sedimentation and the method of electrochemical or electrophoretic purification, gradual or simultaneous processes of hydromechanical sedimentation of pollutants, filtering or flotation processes. The practical significance of the work lies in the fact that it concerns the search for ways to improve the existing technological processes of water purification and increase its quality.