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A pressure-driven electrolytic membrane system of drum type is proposed. Solutions may be effectively separated by combining the pressure-driven electrolytic membrane technique with water cooling of the electrode. The drainage channels from the anode and cathode regions are independent. A method is proposed for calculating the strength of the system’s housing. The required thickness of the outer wall and the fiberglass flanges is determined.

This work has investigated changes in crystallinity and amorphism in the surface layers of commercial microfiltration films. Experimental studies of supramolecular formations and changes in the structure of microfiltration films were carried out by differential scanning calorimetry and X-ray diffractometric measurements in reflection geometry in the region of large angles. In the process of water swelling of semipermeable films of the MMPA, MPS, and МFFK types, a change in the structure of the lattice of the films is observed due to an increase in the interatomic distance, that is, the size of the pore diameter is likely to change throughout the structure of both the active layer and the film substrate. The observed changes in the supramolecular structure of the films upon swelling occur to a greater extent due to the disordering of macrochains in all layers of the films. The decrease in the degree of crystallinity of the films upon sorption of water is most likely associated with the redistribution of the ratio between the number of perfect crystalline phases in polyamide crystallites with different values of the enthalpy of melting.

The article presents the results of a study of mass transfer in the process of electrochemical extraction of iron, magnesium and manganese ions from technological solutions. Mathematical expressions are obtained, and numerical values of empirical coefficients are determined for theoretical calculation of specific outflow, retention coefficient, and average mass transfer coefficients of the electrochemical membrane process of separation of technological solutions. The dependence of concentration polarization on solution flow rate, pressure gradient, and concentration is analyzed.

The article presents the results of calculating the concentration polarization values for electric baromembrane separation of electroplating wastewater based on solving the Nernst–Planck and Poisson–Boltzmann equations with determining the concentration field along the length and height of the intermembrane channel. The dependence of concentration polarization on the solution flow rate, transmembrane pressure, temperature and concentration was analyzed.

A mathematical description of the electrobaromembrane process using an approach based on the Nernst–Planck and Poisson–Boltzmann equations is presented. The hydrodynamic conditions in the intermembrane channel is taken into account by a dimensionless equation based on the Reynolds criterion and a technique is presented for determining electrobaromembrane separation of solutions, taking into account the kinetics of mass transfer and the hydrodynamics of the flow of a solution in an intermembrane channel. Through the use of the technique the local mass-transfer coefficients along the length of the channel of the membrane module may be determined. The technique may also be used to predict and develop laboratory, pilot and industrial electromembrane instruments and plants.

In this work, experimental data on the rejection coefficient and the specific output flux are obtained. Based on the studies, graphical dependencies of the rejection coefficient on the specific output flux were constructed and analyzed. During the analysis, it was noted that with an increase in the output specific flow of the solvent, the rejection coefficient decreases. The reason for this is the boundary layers of fat and protein formed in the near-membrane layers, which prevents the passage of protein molecules through the pores of the membrane. For the theoretical calculation of the rejection coefficient and specific output flux, mathematical expressions are developed and numerical values of the values of empirical coefficients are obtained. The developed mathematical expressions describe the experimental data with good confidence. The obtained experimental and calculated data can be used with great reliability in the calculations of mass-transported flows of substances through semipermeable membranes, as well as in engineering methods for calculating and predicting the effectiveness of the use of membrane processes for the concentration of whey.