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The aim of this work is the utilization of the secondary steam energy through its thermal transformation in electrodynamic dehydrators developed by the authors. To achieve this goal, the use of heat pumps is proposed. A hypothesis is formulated that the use of electromagnetic energy sources in the process of removing moisture from food solutions, followed by the transformation of secondary steam energy, will allow for the formation of reverse energy flows. A method for calculating energy efficiency in the presence of direct and reverse flows is presented. Multistage dehydrators, where electrodynamic systems are used at the final stage and heat pumps at the previous stages, are analyzed. It is shown that the formation of reverse flows significantly increases the overall energy efficiency. The use of an electrodynamic apparatus at the final stage solves the problems of obtaining a highly concentrated quality solution. The application of heat pumps at the remaining stages allows for the efficient use of secondary steam energy. The most significant result is the matching schemes of heat pumps with the dehydrator and the environment. The importance of the work lies in the substantiation and confirmation of the high energy efficiency of organizing reverse energy flows, and the proposed installation with combined systems — electrodynamic and heat pump. By calculation, the modes have been established in which the overall efficiency for two-stage apparatuses with heat pumps can be increased from 0.4 to 0.6, and for four-stage dehydrators from 0.4 to 0.8.

The growing interest in the world for research on microwave processing technologies of raw materials is shown. It has been established that information in available sources is only about laboratory-scale equipment, and theoretical information (models, mechanisms, calculation methods) is practically absent. The aim of the work is to conduct systematic studies in the “extractor — dehydrator — plant material” scheme. To achieve the goal, these electrodynamical systems are presented with parametric, mathematical, and experimental models. The most significant result of the work is that the concept of a “hybrid” process is introduced to explain the mechanism of interaction between the electromagnetic field and the raw material. Using the first law of thermodynamics, it is shown that the “hybrid” process performs work to move the solution from the volume of the material to its surface. As a result, sluggish diffusion processes are accompanied by powerful flows, the driving force of which is the pressure difference in the capillary of the material and the environment. The importance of the work is that new effects are established: mechanodiffusional and vapordynamical. Mechanodiffusional allows obtaining polyextracts in one extractor, and vapordynamical allows the dehydration of the solid phase in the form of two parallel streams — vapor and juice. Experiments were conducted with rosehip fruits, soybeans, tomato squeezes, and sunflower meal. It is shown that electrodynamical dehydrators are characterized by stable performance indicators of vapor generation up to concentrations of 85°brix, at low levels of energy consumption. The results of chemical studies of the obtained samples in electrodynamical devices are presented.

The aim of this work is the energy-efficient equipment creation for production of a high-quality dry product from a plant raw material and development of scientific and engineering foundation for the design of such an equipment. The achievement of this aim lies in a deep analysis of ten-dency in the development of a drying theory and technique. The graph is presented, on the basis of which the development of heat and moisture transfer model of A.V. Lykov is given, taking into account the P. A. Rebinder moisture bond forms specificity. The problems of convective drying modern technologies are determined; the reasons of high-energy consumption during their work are substantiated. The electrodynamic dehydrators classification is given, which con-sideres the combined simple modes (drying) and hybrid dehydration modes. On the basis of the first law of thermodynamics, the possibility of a significant decrease in energy consumption is shown by the organization of a “vapordynamic” effect. The most significant result of the work is the construction of the electrodynamic apparatus module for dehydration of food and medici-nal plant raw material. By the combination of electromagnetic field with the filtration process the specific energy consumptions were 1.9 MJ per 1 kg of the removed moisture, at the hybrid pro-cesses — juice yield exceeded vapor yield by 3.5 times. The significance of the work consists in the fact that the scientific conception of the authors on the possibilities of the significant de-crease in energy consumption during the raw material dehydration at the innovative electrody-namic type apparatuses was practically proven.

This work is devoted to the fresh water deficit analysis. The importance of the research concern-ing water treatment is emphasized. A comparative analysis of water demineralization traditional methods is given and prospects for low-temperature desalination methods are shown. The in-crease in the world interest to the research of the block freezing innovative technologies was es-tablished, the priority in which belongs to the authors of this work. The aim of the work is to improve the block freezing devices during their transferring to a continuous operation mode. Achievement of this aim lies in a proposed universal design of the apparatus, in which the pro-cesses of crystallization, separation and melting of ice are sequentially implemented. A module for a continuous seawater desalination facility was developed. The energy and operational ad-vantages of the proposed method were described. The system modeling of this equipment was carried out. The target function of the modeling determined the key parameters of the process of the ice block gravitational separation — energy and salinity. It was proposed to correct the tradi-tional calculation principles for the outflow in channels by the “capillary drag” coefficient, which takes into account the relief surface of the ice capillaries. A technique for the engineering calculation of ice block salinity during separation was offered. The most significant result of the work lied in the fact of possibility to transfer the block freezing facilities to the continuous mode of sea water desalination with guaranteed salinity indicators. The significance of the work was that an energy-efficient freezing facility with ice recycling for the sea water demineralization in the flow was created.

The analysis of studies devoted to food solutions separation was carried out. The evolution of cryoconcentration technologies is analyzed, including the research works of the authors in the field of the block freezing plants. The purpose of the work is to reduce energy costs in block freezing plants and to intensify the process of the ice block formation. A hypothesis states that energy efficiency can be improved by recycling ice, using its energy to supercool the refrigerant before throttling. To intensify heat and mass transfer during crystallization, a scientific and technical idea for the implementation of the "thermal paradox effect" is proposed. The essence of the effect is that, with a certain combination of design and operating parameters of a block freezer, the growth of an ice block leads to a decrease in the total thermal resistance in the circuit "refrigerant — block freezer's wall — ice block — solution". The most significant result of the work was that it proved the possibility to harmonize the design and operating parameters and organized the process of separation the solutions into ice and concentrate while minimizing systemic cold losses, and, and thus the ways were proposed for developing the freezing concentration technique. The scientific significance of the obtained results lies in the fact that a new prin-ciple of efficient use of the ice block energy was proved in the work, and a new effect was obtained, which it was referred to by the authors as the "thermal paradox". The practical significance of the work was that a multifunctional freezing unit with ice recycling and frequency con-trol of the compressor drive was created.