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The article presents the types of new sorbents used in the industry from the point of view of their application for water purification for various purposes. A review of the literature and a selection of modern sorption materials of the new generation, which are raw materials of Russian production, for the purification of various types of water at thermal power plants to normalized indicators. Laboratory and industrial experiments were carried out to purify wastewater from petroleum products and drinking water from ammonium ions to normalized values using sorption materials APT-1, APT-2, APT-4 and BAU-A. At the Department of TOT of the MEI, work was carried out to study the properties of new sorption materials for the purification of technological, oil-containing wastewater and drinking-quality groundwater at thermal power plants. To determine the operability of sorbents for water purification from ammonium ions, a photocolorimetric analysis of filtrate samples was carried out. The sorption method of wastewater treatment is the most effective and environmentally acceptable method. A filter with a new sorbent should be installed as the last stage of purification of many types of water at thermal power plants to achieve the necessary water quality indicators: at a water purification plant from petroleum products; at a stormwater sewage treatment plant from petroleum products.

Information about the lime composition used for the restoration of limestone is given. It has been shown that using a polysilicate mortar to formulate a lime composition contributes to an increase in water resistance, adhesion strength of the composition to the base, and acceleration of curing. A primer composition is proposed, including liquid sodium glass and calcium chloride.

The article summarizes the experience of using hydraulic excavators in coal, diamondiferous and other mining operations. It is noted that the excavation capacity of modern hydraulic excavators is several times higher than that of the mechanical shovels, and the hydraulic equipment is more suitable for non-explosive excavation in hard grounds, including halfrock formations. It is shown that even in difficult mining, geological and climatic conditions in coal, diamondiferous and other mines, the use of hydraulic excavators in Russian mining companies is justified by high efficiency and high availability ratio equal to the international indicators, which are not lower than those achieved in much more favorable conditions. Research performed in industrial settings made it possible to determine the hydraulic drive's service mode and regulations, as well as rational operating conditions. Operating systems were developed with heated working fluids to compensate for the changing viscosity at low atmospheric temperatures. Based on the tests performed in Russia and abroad, blast-free excavation using hydraulic excavators is done with limited capacity (up to 400 m3/h), and the operating weight of the machines must be not less than 300 tons. The main factors, typical for operation of the open-pit hydraulic excavators include the high annual production time, high forces and dynamics (up to 70 kN per 1 m3 of the bucket capacity) in the digging mode of the unit working at the face, high specific capacity and remoteness from the outside infrastructure used for repairs of the hydraulic components. In the course of testing the hydraulic excavators, the boundary values of the face slope angle depending on the ambient temperature were established. It was experimentally proved that at top to bottom layer-by-layer excavation with the H-285S hydraulic shovel the face height can reach up to 25 m at the rated digging height of 16 m. The average lump size (not more than 300 mm) of the rock mass in a 19 m3 bucket was determined with the permissible oversize in the face up to 2,500 mm. With the normal maintenance quality, the weighted average cost of operation for electromechanical excavators and the corresponding figures for hydraulic excavators are at a comparable level.

Two crystalline phases, which are analogues of common secondary uranyl minerals, namely, becquerelite (Ca[(UO2)6O4 (OH)6]·8H2O) and phurcalite (Ca2[(UO2)3O2 (PO4)2]·7H2O) were identified on the surface of a Chernobyl corium-containing sample affected by hydrothermal alteration in distilled water at 150 °C for one year. Phases were characterized using Single-Crystal X-ray Diffraction Analysis (SCXRD) as well as optical and scanning electron microscopy. Features of the structural architecture of novel phases, which come from the specific chemical composition of the initial fragment of Chernobyl sample, are reported and discussed. Precise identification of these phases is important for modelling of severe nuclear accidents and their long-term consequences, including expected corium–water interaction processes at three damaged Units of the Nuclear Power Plant Fukushima Daiichi.

Chemical degradation of borosilicate glass doped with 238Pu was modelled in conditions of a failed underground radwaste repository in granite host rock with bentonite buffer material after penetration of aqueous solutions at temperature of 90 °C. The total duration of the experiment exceeded two years. It is shown that wet bentonite preserved its barrier function and prevents migration of plutonium to the solution. The total amount of plutonium adsorbed on bentonite clay during the experiment did not exceed 0.02% of the initial amount of plutonium in the glass sample. Estimated accumulated dose of self-irradiation of the glass sample after the experiment varies from 3.16 × 1015 to 3.39 × 1015 α-decays per gram, which is equivalent to more than 1000 years storage of 239Pu doped sample with the same Pu content. Beishan granite remained intact, with no evidence of Pu penetration into the granite matrix along mineral grain boundaries.