Zakharov V. Intensification of membrane processes of purification of nano-filtration permeate of whey

The dissertation is devoted to solving actual problems of intensification of membrane processes in technologies of dairy industry: efficient, rational and most complete use of resources of production and application of membrane processes. Based on the results of our own theoretical and experimental studies, it is scientifically substantiated that the presence in the nanofiltration permeate of whey organic compounds impedes its use as a source of minerals of natural origin and leads to a decrease in the specific productivity of the reverse osmosis membrane. The necessity of combining the processes of ozonation and subsequent sorption purification of the solution by filtration through a layer of activated carbon was proved experimentally. As a result, it allows to remove up to (95±1) % of organic compounds from whey nanofiltration permeate, to realize deactivation of residual ozone and to introduce an increase in the rate of reverse osmotic concentration of the specified solution within 20…30 %. It is experimentally established that to achieve this effect, it is necessary to dissolve ozone within 20…28 mg O3/(dm3 permeate). Due to the statistical analysis of the probability distributions of different parameters by classes, it was found that for the ozonation process the temperature has a greater impact than the ozone concentration in the ozone-gas mixture. The result was a probabilistic statistical model using “machine learning” technology and a validation of this model for the ozonation process. The model allows determining the effectiveness of the ozonation process, depending on the set values of temperature and concentration of ozone in the ozone-gas mixture. The classification accuracy of the developed model is established, for the range of ozone solubility within 60…80 % the classification accuracy reaches 100 %, for other classes the accuracy ranges from 83 to 99 (%), with an average accuracy of 92,25 %, which is a rather high indicator. The resulting model can be adapted to model a wide range of tasks related to baromembrane processes. It is experimentally proved that the use of composite inorganic ceramic membranes allows to carry out the process of electrodialysis at high current density, up to 625 A•m-2. Compared to traditional polymer ion-exchange membranes, modified membranes have a higher resistance to contamination with organic compounds and are less susceptible to chemical attack. It is proved that under the same research conditions, the intensity of desalination, decrease of electrical conductivity, of NF permeate by electrodialysis is almost is 7,5 times higher compared to the desalination of whey. On the basis of the results obtained, the equipment and technological schemes of treatment of whey nanofiltration permeate using an ozonation station (which are protected by the Ukrainian patent for a utility model) were proposed. The results obtained in this work are implemented in the production of the dairy processing plant of PJSC «Gorodenkovsky cheese factory» and the private enterprise «Logrus», as well as in the educational process of the National University of Food Technologies.