FEATURES OF ELECTROACTIVATED WATER PRODUCTION AT A COAXIAL ELECTRODE LOCATION

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Introduction. The amazing properties of water ob- tained by electrolysis were discovered in different coun- tries independently. The unusual properties of the electro- activated water were discovered by chance, not by the doctors, but by the gas workers, not in the laboratory, but on the drilling test towers of the Institute SredAzNIIGaz. This institute was located in Tashkent and was engaged in gas production in the Kyzyl Kum desert. The scientists of this institute came up with an original installation: on the basis of electrolysis, two solutions were obtained from ordinary water. One of them, catholyte, was used to pro- duce drilling mud with high physical and chemical indi- ces. Another solution - anolyte - was used for coagula- tion of excess clay phase. The study and use of electroactivated water solutions began in 1978 in the organization “Sreda-3 NIIgaz”, where S. А. Alekhin, V. M. Bakhir, N. A. Mariam- Polsky, U. D. Mamadzhanov et al. worked [1-3]. Three international symposiums were held on the elec- trochemical activation of water and aqueous solutions [4-6]. In the introductory report at the first symposium the President of the Academy of Medical and Technical Sciences of Russia, Doctor of Technical Sciences, Profes- sor. B. I. Leonov noted that “electrochemical activation of water and water solutions is the technology of the future, which will allow creating an ecologically clean future for the Earth and other planets”. Further work confirms the conclusion of the scientist [7-9]. The widespread use of activated water is presented in article [10]. Water with pH 2-3 was introduced into a solution of ferric chloride for etching printed circuit boards [11]. The etching rate has increased, the consump- tion of chemicals has decreased, the process of industrial waste regeneration has been simplified. For cleaning printed circuit boards, a composition consisting of electro- activated water (pH 12-14) and caustic soda has been developed [12]. The cleaning time is reduced several times. When cutting metals, the redox potential of the emulsion was measured at the time of chip removal. As soon as the cutting began, the redox potential became negative. Having added electroactivated water (catholyte) with redox potential from minus 300 to minus 800 mV to the emulsion, a new coolant-lubricant was obtained [13]. Working on the process of industrial waste utilization, the authors improved the previously developed coolant- lubricant. The activator was close to the metalworking machine. At the same time, the catholyte was directed to the cutting zone, and the anolyte was mixed with the spent emulsion. The effect of increasing the cutting tool durability was obtained, the emulsion stability increased 1.5 times, and the used coolant did not require additional treatment for utilization [14]. For washing printed circuit boards, various liquids are used. In the study [15] electroactivated water was used for this purpose, which led to a reduction in the consumption of chemicals. To obtain electrochemically activated water and solu- tions such devices are used as: STEL installations, Aquachlor, Izumrud; flow modular elements PEM-3, PEM-7, PEM-9; universal MB-11, MB-26, etc. With a small consumption of activated water, a large variety of electroactivators are offered: Iva-1, Melesta, AP-1, Aqualife and others (fig. 1). Analysis of the structures of these devices showed that flat metal plates are used as electrodes, therefore there are volumes of water that are exposed to uneven electro- chemical effects. In addition, due to the small surface area of the electrodes, the current density increases, which, according to the Tafel equation, leads to an increased overvoltage of electrochemical processes. As a result of this, the specific energy consumption for obtaining acti- vated water is significant and amounts to 15÷30 W · h / l. The calculation is made on the basis of passport data. In the Espero-1 electroactivator shown in fig. 2, the anode is made in the form of a graphite rod of square sec- tion, the cathode is made of thin-sheet steel in the form of a cylindrical shell. The electrodes are mounted coaxially to each other. The anode is in the center, the cathode is in the periphery. As a result, all the water in the activator is sub- jected to electrochemical exposure, which leads to a sig- nificant reduction of energy consumption to 2÷3 W · h / l (when dissolving table salt in water 10 g/l). On the side surface of the anode, due to the right angle, the electric field strength and current density are increased, which adversely affects the efficiency of the electroactivator. Methods and equipment of research. To study the activator with a coaxial arrangement of electrodes, a de- vice with a graphite rod of circular cross-section was manufactured [16]. Fig. 3 shows an experimental electro- activator. Tarpaulin cloth is used as the diaphragm. The anode is a graphite rod, the cathode is a hollow stainless steel cyl- inder. Fig. 4 shows the assembled electroactivator, power supply, multimeter and pH meter. Methods of conducting experiments in the study of electroactivator with a coaxial arrangement of electrodes: 1. Filling the glass tank with cold tap water. 2. Settling water with the lid open for at least 8-10 hours at room temperature. 3. Control the pH of the source water. 4. Filling the anodic and cathodic spaces of the activa- tor with water. 5. Installation of the electrode in the anode space. 6. Pause from 3 to 5 minutes to level the water levels in the cathode and anode spaces. 7. Electrochemical effect on water by passing a cur- rent. 8. Current control. 9. After disconnecting the voltage, the anolyte is dis- charged into a separate container. 10. Control of pH of the anolyte (pHA) and the ca- tholyte (pHK). Fig. 1. Electric water activators: Iva-1, Melesta, AP-1 Рис. 1. Электроактиваторы воды: Ива-1, Мелеста, АП-1 Fig. 2. Electroactivator “Espero-1” Рис. 2. Электроактиватор «Эсперо-1» Fig. 3. Experimental electroactivator Рис. 3. Экспериментальный электроактиватор Fig. 4. Used equipment Рис. 4. Используемое оборудование Fig. 5. The change in pH of anolyte and catholyte from the time of activation of tap water Рис. 5. Изменение pH анолита и католита от времени активирования водопроводной воды Specific energy consumption is determined by the formula: Q = I · U·τ/60·V, (1) where U is the voltage on the electrodes, V; V is the vol- ume of activated water, l; I is the amperage, A; τ is the time of water activation, min. We believe that the specific energy consumption does not reflect the efficiency of the electroactivator. It is pro- posed to evaluate the operation of the device according to the following indicator: q = Q/ΔpH, (2) where q is the specific energy consumption per unit of change in the pH of water or an aqueous solution; ΔpH = pHK - pHA is the difference in pH values of ca- tholyte and anolyte. The experiments were conducted at a different ratio of the volumes of anolyte and catholyte from 0.35 to 1.72. Results. Experiments have shown (fig. 5) that the minimum value of specific energy consumption per unit of pH change is typical for a volume ratio of 0.57, therefore, further experiments were carried out with this ratio. It can be seen from the figure that with electrolysis time from 3.5 to 7 minutes specific energy consumption for the specified ratio of volumes is 15-20 % less than for other values. Fig. 6 shows the changes in the pH of anolyte and ca- tholyte from the time of water activation. It follows from the graph that the maximum change in the hydrogen index (pH) occurs in 7 minutes of electrochemical activation of water. For the experiments an aqueous solution of sodium chloride (0.9 % physiological solution widely used in medicine and in everyday life - the Espero activator) was used. The results are presented in fig. 7, 8. The nature of the change in the pH of the solution and the specific energy consumption does not change with the activation time. However, the specific energy consumption is an order of magnitude less and the maximum change in the pH value occurs in 3 minutes. Fig. 6. The change in pH of anolyte and catholyte from the time of water activation Рис. 6. Изменение pH анолита и католита от времени активации воды Fig. 7. Specific energy consumption per unit of change using an aqueous solution of sodium chloride (0.9 % physiological solution) Рис. 7. Удельные энергозатраты на единицу изменения с использованием водного раствора хлорида натрия (0,9 % физиологический раствор) Fig. 8. The change in the pH of the anolyte and catholyte from the time of activation of water using an aqueous solution of sodium chloride (0.9 % physiological solution) Рис. 8. Изменение pH анолита и католита от времени активации воды с использованием водного раствора хлорида натрия (0,9 % физиологический раствор) Specific energy consumption per unit of change in the water pH Model Ratio VА /Vk Specific energy consumption q Melesta 0.6 2.86 AP-1 0.33 2.77 IVA-1 0.75 2.96 Aqualife 0.11 2.76 Espero-1 0.2 1.5 Electroactivator under study 0.57 1.25 The results of the calculations of the specific energy consumption per unit of change in the water pH are shown in the table. It follows from the table that the elec- trical activator has the minimum value of specific energy consumption per unit of change in the pH value. Conclusion. Existing devices for the electrochemical activation of water and aqueous solutions have design flaws, and therefore have increased specific energy con- sumption. The developed electroactivator with a coaxial arrangement of the electrodes has the lowest specific en- ergy consumption per unit of change in the pH value, which is very important at the present time.

About the authors

E. B. Pshenko

Reshetnev Siberian State University of Science and Technology

Email: pshenko-64@mail.ru
31, Krasnoyarsky Rabochy Av., Krasnoyarsk, 660037, Russian Federation

I. Ya. Shestakov

Reshetnev Siberian State University of Science and Technology

31, Krasnoyarsky Rabochy Av., Krasnoyarsk, 660037, Russian Federation

V. I. Shestakov

Reshetnev Siberian State University of Science and Technology

31, Krasnoyarsky Rabochy Av., Krasnoyarsk, 660037, Russian Federation

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