| abstract
| - DPIE - discrete-pulse input of energy in heterogeneous environments. The principle of DPIE defines ways of direct transformation of energy continuously entered into the device to the short-term impulses of the high capacity which have been discretely distributed in working volume /1// Thermal vacuum fluid processing technology developed at the Institute of Engineering Thermophysics of NASU. It is constructed on DPIE mechanisms, in it processes of adiabatic boiling up and cavitation at sharp pressure differences in a combination to heating and cooling of a stream of liquid/2,3/are used. Water in this work was considered as a substance existing in the nature with impurity peculiar to it and inclusions. Thermal vacuum technology in the processing of fluids produces a number of new effects. So. water treatment, significant changes in the composition and structure of the impurities, as well as abnormally high values of pH (pH). The pH of the water is determined by the presence of oppositely charged ions H + and OH -, r. K Water as a way to dissociate the N / 4 /: H2O ⇄ H + + OH - In the equilibrium condition with equal concentrations of H + and OH - water has a neutral reaction. When equilibrium is disturbed by excessive concentration of H + ions, it has an acid reaction with an excess concentration of OH - alkaline. The cause of imbalance can be either a chemical interaction with the impurities of water, or physical effects on the structure of water. Chemical interactions are determined by the presence of impurities in the water that can connect to the ions H+ and OH-. External influences on the water in the form of various fields, freezing and subsequent thawing, etc. also contribute to changes in pH. The most significant changes are observed in his tight acoustic cavitation, when there is destruction of the water molecules to break covalent bonds and the formation of new compounds: H *. OH *. H +, OH, O, H2, N2O2 at the time of the collapse of cavitation bubbles in the event of supercritical regimes with high temperatures and pressures. By the end of this mechanism is not understood, but there are quite a number of experimental data to support this phenomenon. / 5,6,7,8,9,10,11 / B / 11 / experimental data processing water tight acoustic cavitation resulting in pH values increased to 8 - 8.1 and lasted from several seconds to several hours. A fundamentally new result in our experiments is that the processing of thermal vacuum technology pH persists for more than two years. This suggests that the water is maintained excess concentration of OH-and there are no free H+ ions. PH value can be determined for many chemical, technological and biological processes, so the study of this phenomenon is both scientific and practical interest. Description of thermal vacuum processing technology liquids. Thermal vacuum technology is a series of sequential interrelated processes in the liquid flow: dispersion, condensation, heating, cooling, boiling, evaporation, pumping pumping with the possible effects of cavitation (Fig. 1) Fig. 1. Thermal vacuum processing technology liquids: 1, 3 - condensation of 2, 4, 7, 9 - increase in pressure, 5 - input of heat into the system, 6, 8 - evaporation, 10 - removal of heat from the system. The technology uses a process of adiabatic boiling when previously accumulated in the internal energy of the liquid is realized at the end of the superheated liquid flow through the nozzle aperture, or in the form of growing at a high rate of steam bubbles, which in a short segment of the path is transformed into vapor-liquid flow of liquid to form a bubble, and then film structure. Thin films at the exit of nozzle to break down the formation of small droplets with a size of several micrometers and nanometers. In the process of bubble growth is continuous updating of the interface. These dynamic processes occur in the time scale of nanoseconds. In space between bubbles there is complex hydrodynamic conditions with the formation of macro-and microvortices, high turbulization of liquid and high shear stresses. On the surface of droplets formed in the process of evaporation at a rate close to the rate of evaporation in a vacuum, and also to update the interface. Resulting vapor is fed into the region of the dispersed liquid cooled, where it condenses on the surface of the droplets and films. Experiments were conducted on the production line, using a specially designed apparatus that implements the thermal vacuum technology. The scheme of the apparatus is shown in Fig. 2. Fig. 2. The scheme of the apparatus for processing a liquid: 1 ... 4 - vacuum chamber, 5 - heat exchanger for heating fluid, 6 - centrifugal pumps, 7 - vacuum pump, T, F - sensors for measuring temperature and pressure, respectively. Chilled water in the dispersed condition continuously moves consistently in 1 and 2 chambers of the device where the set depression is supported. Then the water is fed into a heat exchanger for heating to a predetermined temperature and comes in a series 3 and 4 of the camera, which is also supported by a vacuum. After that, the heat exchanger for cooling. Temperature and pressure sensors were installed at the points shown in Figure 2. Researches were carried out in a range of temperatures 4 to 1000C under a pressure differential of ten-fold from 1 to 0.1 atm, water overheating with respect to the saturation temperature reached 50 C. In the experiments we used water from wells in different regions. Investigated: - change in physical and thermophysical properties of water; - chemical impurities in the converted water, their structure and size distribution; - change in pH (pH) as a function of water in the heat flow through the steps of processing and storage time. As a result of researches the following was established. 1. When water treatment technology for thermal vacuum changed a number of physical and thermophysical parameters: electric conductivity, galvanic current, specific warmth of steam formation, kinematic viscosity, remains unchanged redox potential (Table 1). Analyses were carried out in conjunction with the Institute of Physics, National Academy of Sciences of Ukraine. 2. The chemical composition of impurity of initial water changes. Analyses were carried out on 17 parameters according to existing State standards in the certificated laboratory of the Ukrainian research institute of alcohol and biotechnologies of food products. Results are given in Table 1. Table 1. Changes in physical characteristics of water in the processing of thermal vacuum technology. Parameters The original water Water is treated at 80°C Electric conductivity, μS 501 428 Oxidation-reduction potential, mV +221 +221 Galvanic current, с.е. 125 115 Specific warmth of evaporation, J/kg 2187,22 2265,86 Viscosity kinematic, m2/s 1,01543•10-6 1,01080 •10-6 General rigidity, mmol / dm3 4,4 2,85 General alkaline, mmol / dm3 5,4 3,92 Mass concentration of hydrocarbonates, mg/dm3 351 300 Hydrogen indicator, рН 7,6 8,9 As can be seen, decreasing total hardness, total alkalinity, the mass concentration of hydrocarbons. Changes the microstructure and grain size distribution of impurities, which were determined from the dry residue: increases the dispersion and structure (Fig. 3). a) b) Fig. 3. The change of the microstructure of dry residue (increase 1600h): a - water source, and b - water treated. 3. Most essentially the size of a hydrogen indicator (рН) changes. In experiments it reached values 9 – 9,2 at a reference value 6,8-7. It was found that pH changes in stages of processing, as shown in Figure 4. In the first and second stages of a rate increase is observed, when heated in a heat exchanger after the cameras pH 1.2 significantly reduced. The main increase in pH is observed at 3-4 stages, degree of improvement depends on the heat flow at the inlet to the chamber 3 (Fig. 2). Fig. 4. Change рН on stages of processing of water: 1–initial water; 2–after condensation chambers (fig. 2, item 1, 2); 3–after heating to 95 °C; 4–after boiling up chambers (fig. 2, item 3, 4); 5–after cooling. Figure 5 shows the results of experiments to determine the pH dependence of the heat of water at the entrance to the zone of adiabatic boiling - in the chamber 3. When the water subcooling to the saturation temperature and superheat to 10 - 15 C, the pH does not change and remains constant. With the increase of heat, as the process of adiabatic boiling, the pH begins to rise. Maximum value in this series of experiments on a 9.2 overheat reached 500C. Fig. 5. Changing the pH, depending on the heat of water. Long-term researches have been carried out changes in pH during storage. Hermetically sealed envelope with the treated water was stored at 18 -220 C for more than two years. The results of observations are shown in Figure 6. During this time, the pH value remained virtually unchanged. Fig. 6. Change of pH during storage of treated water. In nature, there is no absolutely pure water. It is always present as impurities in the gas, FIR organic and inorganic compounds, which determine the number of its properties and for many reactions. In water treatment technology for thermal vacuum in the first two stages as a result of the partial vacuum and heated removed a large (up to 50%) of the gaseous component of the impurities. The highest solubility in water has carbon dioxide, which forms carbonic acid with it / 4 / СО2 + Н2 О Н2 СО3 (1) Which dissociates Н2 СО3 Н+ + НСО3 - (2) НСО3 Н+ + СО3 2- (3) As a result, the water creates a high concentration of H+ ions. At removal from water of carbon dioxide of reaction (1) - (3) shifted to the left to decrease the concentration of free H+ ions. At the same time decrease the mass concentration of bicarbonates, total hardness and total alkalinity and, consequently, increases the pH value. We analysed and experimentally checked a contribution of CO2 to change рН when processing water on thermovacuum technology. Complete removal of CO2 in combination with pumping and heating leads to a change in pH of 5-7% of the final result. Increasing the pH to 3-4 stages determined by the conditions of adiabatic flow boiling: a sharp drop in pressure determines the sharp phase transition with the formation of thin films and droplets on the surface of which is evaporating. These processes lead to an abnormally high and persistent increase in pH. Comparing this value with various methods of treatment shows that the thermal vacuum technology it is much higher than the removal of CO2 and a rigid cavitation (Fig. 7) Fig. 7. The pH of the various methods for water treatment. To explain the results hypothesized based on the polarization of the ion model of the structure of water / L 12, 13, 14 /. It is known that the water molecule is a dipole, which contains positive and negative charges at the poles, which determines its ability to intermolecular interactions through hydrogen bonds. Each water molecule can form hydrogen bonds with four neighbouring molecules, forming a delicate mesh cage. Under certain conditions, the system of hydrogen bonds may have various defects, including the possible formation of a complex N5O2 + to consists of two molecules of H2O, involving short strong hydrogen bond scheme, as shown in Figure 8. As a result of the formation of such complexes of released ions OH-B / 15 / describes the conditions necessary for the emergence of such systems: low pressure, presence of water in thin films and nanosized volumes, sharp phase transitions. Fig. 8. Structure of complex H5O2 +. Comparison of conditions that cause defects in the structure of water, with the conditions of flow processes in the thermal vacuum technology, reveals that they are very similar: low-pressure phase transitions are sharp, nanoscale droplets, thin films, the intense turbulence and high shear stresses in the space between bubbles in an adiabatic boiling . On this basis, it can be argued that the cause of excessive concentration of OH-ions in the water after treatment by thermal vacuum technology is formation of complexes H5O2 +. Results of researches of changes of properties of water are given in this work when processing on thermal vacuum technologies and a hypothesis explaining the reason of change of a hydrogen indicator. The pH of the defines for many chemical, technological and biological processes. In practice, the change of pH is achieved mostly through the input of chemicals, which is not always beneficial to the final result. The presented technique allows to obtain the specified pH of the water without adding any additives. This can be used in many branches of human activity. For example, in a spa treatment, particularly in gastroenterology, when long-term use of mineral water with high pH can lead to unwanted mineralization of the body, using water treated by thermal vacuum technology, which can have an arbitrarily low mineral content, will not have unwanted side effects. In the food industry, water with such properties can be used in cheese-maker and when processing meat. In the pharmaceutical, microbiological and medical industry, it can be used in many industrial processes. It is possible to tell surely that the represented technology has wide prospect of application in real technologies. With regard to the scientific aspect of the work, the experimental data extend the notion of the possibility of changing the properties of water due to changes in its structure - the first place, and may confirm experimentally a number of provisions of the polarization model of water structure. 1. Долинский А.А., Иваницкий Г.К. Тепломассообмен и гидродинамика в парожидкостных дисперсных системах. Теплофизические основы дискретно-импульсного ввода энергии. Проект «Наукова книга» Киев, Наукова думка, 2008. 2. Шурчкова Ю.А. Адиабатное вскипание. Практическое использование// Изд-во «Наукова думка», 1999, 225 с. 3. Долинский А.А., Басок Б.И., Гулый С.И., Накорчевский А.И., Шурчкова Ю.А. 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