This paper is devoted to the electrochemical and chemical aspects of the erosion-corrosion destruction of the surface layer of a wet-steam turbine rotor blade under the influence of an electrified working fluid. It considers a hypothesis about a complex mechanochemical-electrochemical mechanism of chromium and iron wash-out from the surface layer of the rotor blade metal during the destruction of the oxide film under the influence of a high-speed wet steam flow. Various versions of this process are analyzed for positive, negative, quasi-neutral, and neutral electrifications of wet steam. The possibility to hydrogenate the surfaces of rotor blades under the influence of negatively-charged droplets is shown theoretically. The damage to the blades in this case is similar to that from anodic etching. It is also shown that the process of blade surface hydrogenation takes place in any case both for electrically-charged droplets and for neutral ones. However, in the case of neutral droplets, the intensity of the process is insignificant. An experimental study was carried out for the erosion-damaged surface of a last-stage rotor blade from of the BK-50 LMP turbine that had exhausted its lifetime. The quantitative content of chromium was determined in the steel sample cut out from the blade. A decrease in chromium content in the erosion-damaged blade surface layer was found. To test the hypothesis about the similarity between the process of anodic electro-etching and the process of surface destruction under the influence of negatively-charged droplets, an electrochemical experiment was carried out on a model sample of 20X13 chromium steel. The reliefs of the damaged areas on the model sample after anodic etching and on the observable blade in the zone of exposure to negatively-charged droplets are shown to be similar. The experimental studies have confirmed the presence of a complex mechanochemical-electrochemical process of blade destruction. On the basis of the data obtained, recommendations for extending the useful life of turbine blades are formulated.

In the mining and industrial regions of Ukraine, a large amount of mine and quarry waters is formed. Due to high mineralization, they cannot be discharged into natural hydrographic objects without deep processing, including demineralization. Most of such waters are significantly contaminated with concentrates of sulfides and dissolved iron compounds, which hinder their further purification. At the same time, thermal power plants located in these regions consume a significant amount of scarce drinking water for their needs. Deep processing of mine and quarry waters allows to clean them and obtain feed water for heating systems, boilers of TPPs and CHPs. A method of obtaining stable inert titanium-based anodes with an active coating of PbO2, which do not contain noble metals and their compounds, has been developed. The method consists in protecting titanium from passivation with an oxide film by thermally applying a MnO2 coating, and later applying to the base with this coating a thin layer of PbO2 from an alkaline complex electrolyte containing 2.5 mol/dm3 NaOH, 0.6 mol/dm3 EDTA, ethylene glycol additive and is a saturated PbO. The main 3–5 mm thick layer of coating is applied from the nitrate electrolyte, which includes Pb(NO3)2 1 mol/dm3, Cu(NO3)2 0.4 mol/dm3, Al(NO3)3 0.2 mol/dm3 and the gelatin additive. A method of extending the service life of an alkaline electrolyte by reduction of Pb (IV) compounds during the contact with the active surface of metallic plumbum is described. The conducted resource tests of this anode for 1400 hours proved its stability when processing solutions containing a mixture of sodium sulfate and sodium chloride. On the basis of this anode, the technology of electrochemical deironing of mine waters and removal of sulfides from them before demineralization was developed and experimentally tested. This technology is the only possible method of reagent-free iron removal and removal of sulfides from waters with high mineralization. Such anodes significantly expand the scope of application of electrochemical processes. They can be used not only for water treatment in thermal power generation, but also for the treatment of wastewater of various mineral and organic composition, chemical and technological processes for obtaining oxidants, etc.

Water is considered as the working fluid of wet steam turbine units. The importance of a purposeful change in the thermophysical properties of water used for energy needs is indicated. A reagent-free method (transverse magnetic field of permanent magnets) of influence on water is proposed. Literature data on currently available papers dedicated to the study of water properties is presented. It is shown that the mechanisms of influence of external physical fields on the physicochemical and thermophysical properties of water have not been elucidated as of now. It is emphasized that the properties of distilled water during exposure and after exposure to physical fields are even less studied. The currently existing contradictions between theoretical ideas about the properties of water and experimental results are considered. It was found that currently there are no correct methods and equipment capable of indicating changes in water properties in real time. As a solution, the equipment and method of analyzing the optical density of distilled water is proposed. The shortcomings of most existing experimental works on the study of the influence of physical fields on the optical density of water are analyzed. The requirements for devices intended for measuring the optical density of distilled water are formulated. A stand was made and experimental work on the study of the dependence of the optical density of distilled water on the induction of a magnetic field that affects it was carried out. It is proved that the magnetic field affects the optical density of distilled water in the infrared range of wavelengths both in the direction of increase (4.1%) and in the direction of decrease (1.7%) depending on the induction of the magnetic field and the speed of water flow through the working section of magnetization device. A hypothesis explaining the obtained result is proposed.

The accumulation of highly mineralized waters and brines in the mining-industrial regions of Ukraine carry a threat of salt pollution of underground and surface water sources. Low-waste processing of these waters is prevented by iron compounds, hydrogen sulfide and sulfur-containing organic compounds. The process of accumulation of iron compounds in brines and groundwater in the presence of hydrogen sulfide has been studied. Comparative calculations of the thermodynamic potentials of the corresponding reactions have been carried out. The calculation results are confirmed by experiments on model solutions and brine of the Dombrovsky quarry. To remove iron compounds from brines and other highly mineralized waters, it is proposed to use electrolysis with inert anodes. It was found that 99.9% of iron compounds pass into the precipitate of iron hydroxide (III). At the same time, the overwhelming amount of heavy metals also passes into the sediment.

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