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Документ Наукові засади баро- та електромембранних процесів харчових технологій(2018) Змієвський, Юрій ГригоровичДисертація присвячена вирішенню важливої науково-практичної проблеми розроблення наукових засад баро- та електромембранних процесів у технологіях харчових виробництв. Запропоновано гіпотезу селективного розділення лактози на зворотноосмотичних мембранах при її різній концентрації. Науково обґрунтовано раціональні режими та рівень концентраційної поляризації процесу нанофільтрації молочної сироватки. Отримали подальший розвиток теоретичні уявлення процесу формування осаду під час нанофільтрації. Обґрунтовано режими процесу діананофільтрації молочної сироватки. Розкрито механізми масоперенесення в модифікованих іонообмінних та полімерних мембранах, доведено їх ефективність. Показано ефективність зворотного осмосу в технології концентрування цукрових розчинів. Запропоновано апаратурно-технологічні схеми комплексної переробки молочної сироватки та концентрування розчинів цукрового виробництва. Результати досліджень впроваджені у виробництво на підприємствах молочної та спиртової галузі, а також у навчальному процесі Національного університету харчових технологій. The thesis for obtaining of scientific degree of doctor of technical sciences by specialty 05.18.12 – processes and equipment of food, microbiological and pharmaceutical productions. National University of Food Technologies, Kiev, 2018. This dissertation is devoted to the development of scientific principles of baromembrane and electromembrane processes in the treatment of milk whey, distillery stillage and for sugar production. On the basis of experimental results an abnormally high lactose permeability was detected through the reverse osmosis membrane at low concentrations of lactose. A hypothesis about the formation of lactose in the solution of nuclides (associates) with increasing concentration was made. Due to the large geometric sizes of these nuclides, the selectivity of the studied membranes by lactose increased by at least 20 %. It has been established that the use of nanofiltration in the processing technologies of milk whey ensures reduction of specific energy consumption for concentration and demineralization of the solution in the range of 20-30 % in comparison with the reverse osmosis. In this case, the fat phase in milk whey before nanofiltration should not exceed 0.060±0,005 % under the pressure of 1.5 MPa. It is proved that the adsorption of proteins on the surface of the membrane occurs in the middle of the flat channels of the nanofiltration installations. The layer of adsorbed proteins creates a hydraulic resistance, which is almost 5 times more than resistance of the membrane itself. In present work we've gotten scientifically substantiated rational hydrodynamic regime for separation of milk whey in a rectangular 39 nanofiltration channel 1 mm high. With an increase of value Reynolds number, the degree of dewatering of the solution decreases, which is associated with a decrease in the concentration polarization. By using the developed mathematical model, the distribution of the concentration of dissolved substances, the horizontal and vertical components of velocity by height and length of the channel for the nanofiltration unit of the milk whey. The combination of the proposed mathematical model with experimental data allowed us to determine the rational level of concentration polarization for this process. The analysis of the composition of the nanofiltration permeate of milk whey has shown the prospect of its processing in order to obtain purified water and concentrates of minerals, suitable for use in remineralization of drinking water. The rational regimes of the reverse-osmosis for concentrating of the indicated solution are established. The concentrates obtained should be directed to electrodialysis with conforming concentration cameras. This ensures lower energy consumption due to the better electrical conductivity of the solution and smaller capacity of pumping. Low concentrations of calcium and magnesium ions in it make impossible the formation of hardly soluble precipitates on ion exchange membranes, which simplifies the implementation of this process. Electrodialysers with non-protic concentration cameras allowed to obtain solutions containing mineral substances of 140-180 kg/m3, which are suitable for use in the technologies of remineralization of potable water. New experimental results for treatment (concentrating) of filtered juices from second saturation at sugar production by reverse osmosis were obtained, determined mass-transfer coefficients, depending on the flow rate of the solution. This technology is promising, but requires more detailed technical and economic analysis. The lack of heat-resistant back-axis membranes complicates the introduction of research results into production. The process of diananofiltration of milk whey is investigated. Under the conditions of experiments, a concentrate with a demineralization level of 62 % was obtained, which is almost 35 % higher than with conventional nanofiltration. Thus, diananofiltration may be an alternative to electrodialysis if, from a technological point of view, the demineralization level within the 60 % range is acceptable. The efficiency of the modification of ion-exchange heterogeneous membranes by inorganic nanoparticles of zirconium for electromembrane processes is confirmed. It was found that antimony of functional groups located on the surface of nanoparticles introduced in transport pores take part in the transport of ions, while nanoparticle units localized in intergranular spaces serve as a barrier for the penetration of quions and organic compounds to the membrane. In the case of desalting of the milk whey, the charge selectivity of the ion-exchange heterogeneous membranes increases by a third. The properties of the mechanism of modification of polymer composite and track membranes for baromembrane processes are established. In this case, the zirconium nanoparticles are concentrated on the pore surface, which leads to an increase in the selective properties of the membrane due to the formation of a secondary porosity with pore size of 100 nm.