Definition of the Change Regulations in the Porosity of Semi-permeable Membranes After the Separation of Dairy Raw Materials

Abstract

Topicality. The article provides a methodology for calculating structural and physical characteristics of semi-permeable membranes after their use in the technological process. During the operation of the membranes, the permeability decreases due to the clogging of their pores with colloidal substances. As a result, it is necessary to obtain data on the distribution of pores on the surface of the investigated ultrafiltration membrane. The aim of the article is to determine the change regularities in the porosity of the semi-permeable membrane, which is used in the technological process of separating dairy raw materials. This will make it possible to predict hydrodynamic properties of the ultrafiltration membrane. Research methods. A strain-measuring (statistical) method is offered, as well as structural and physical characteristics of semi-permeable membranes are determined in the process of membrane filtration of skimmed dairy raw materials. The possibility of constructing mathematical dependencies and methods for determining physical properties and structural analysis of the semi-permeable membrane is highlighted. This technique makes it possible to define not only the surface of the semi-permeable membrane, but also the surface of the polarisation layer of high molecular weight substances. Results. Based on the research results, the dependences of physical properties and structural components of the semi-permeable membrane after the processing of dairy raw materials are constructed. The results of the conducted study show that after ultrafiltration of skimmed dairy raw materials, the pore sizes undergo significant changes. Conclusions and discussion. An increase in the number of pores with a diameter of less than 10 nm is established. The spectrum of the radii of microcapillaries shifts towards decreasing, which occurs as a result of the deposition of particles of the dispersed phase in the microcapillaries. The implementation of research results can take place in industrial conditions, in order to determine the structural and physical characteristics of different types of membranes during the concentration of liquids of different origins for the development of new modifications of filter elements. The conditions for the industrial use of the obtained results are the resolution of issues relating to the laboratory studies of structural and physical characteristics with production results.