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Background. A number of studies is being carried out aimed at accelerating the firing process of ceramic masses due to mechanical activation, which saves energy and improves the quality of the product. We note the low level of scientific research in this area in our country. Purpose. The purpose of the study: to analyze the possibility of using the mechanical activation method to improve the quality and reduce the cost of ceramic products based on loess-like rock. Methodology: Modern methods of physical-chemical and physical-mechanical studies were used, including laser diffraction (diffraction analyzer ANALYSETTE 22 Nano Tec plus.), X-ray and electron microscopy methods. Originally. It is shown that the mechanical activation of loess-like rocks leads to an increase in the number of clay particles by 63.7%, dust particles by 28.25%, and a decrease in the number of sand grains by 58.7%. It is noted that the technological properties of this mass have changed, including plasticity - from 5.0 to 10.4; semi-finished product compressive strength - from 1.09 to 1.24 MPa. Findings. It is shown that the optimal grinding time is 120 min. The plasticity of the formed mass is increased by (94.6%). The grinding of loess-like rock and glass flour leads to an increase in the amount of clay particles by 63.7%, dust particles by 28.25%, and sandy particles by 58.7%. The compressive strength can be increased (86.5%) and the cooking temperature is reduced by 50°C. [ABSTRACT FROM AUTHOR]

Waste of combined heat and power plants represents a certain danger to the environment, and hence the economic problems. However such waste contains substances that are advisable to use for production of construction and finishing materials. Technogenic products of water treatment from the Yuzhnaya combined heat and power plant (sludges of chemical water treatment – code 8410500) are a calcite mixture containing more than 64 wt. % calcite. The mineralogical composition of inorganic waste has been determined while using X-ray and IR-spectral researches. Mechanical activation of calcite inorganic wastes leads to grinding of calcite and a decrease in the amount of adsorbed water, which affects the increase in the content of silica frame structures, the reactivity of which directly depends on their quantity. Changes in the structure of silicon dioxide during mechanical activation are established according to IR studies. The results of X-ray and IR studies of the Zapolie deposit clay used in ceramic brick production technology make it possible to attribute it to raw materials with high reactivity. An experimental batch of ceramic bricks has been produced at JSC “Obolsky Ceramic Plant” with addition of calcite inorganic waste from combined heat and power plants. An X-ray diffraction analysis of samples of the obtained bricks having standard composition and with addition of waste has been carried out. The influence of calcite inorganic waste content in the feedstock on the process of ceramic brick structure formation has been stu-died in the paper. Addition of chemical water treatment waste containing calcium carbonate up to 15 wt. % to the Zapolye clay mixture helps to reduce a firing temperature and an appearance of the melt. This leads to crystallization processes of solid minerals from the melt and an increase in the amount of glass phase which contributes to improvement of strength properties in ceramic bricks. The possibility of using inorganic waste (sludges of chemical water treatment – code 8410500) of combined heat and power plants as a component of emaciated additives in clay raw materials in the process of ceramic brick production has been established in the paper.

A comparative analysis of the mineralogical composition of the clay fraction (< 1 μm) of chestnut soil and solonetz has been performed in the article. Soils were studied in the oldest part of the Caspian lowland in north-west where the microrelief is not quite apparent (microdepressions no more than 5–10 cm depth), but with a contrast soil cover. The content of silt fraction in chestnut soil varies from 25.6 to 33.9%, in the solonetz – from 11.7 to 51.6%. In all horizons of the compared soils, except for the upper surface horizons (SEL, AU1), mixed-layered minerals dominate (39–52% in the fraction) over illite (27–37% in the fraction). In the surface horizons illite (48%) dominates over mixed-layer minerals (35%). The compared soils have some similarities in their crystal-chemical state: the imperfection of the kaolinite structure and the superdispersed state of the mixed-layer phase in the upper horizons, as well as the appearance of individual smectite and chlorite packets in the mixed-layer phase in the lower horizons (BC, C). The degree of perfection of the kaolinite structure both in the solonetz and in the meadow-chestnut soil increases towards the bottom of the profiles. The obtained data allow suggesting that in the meadow-chestnut soil the clay phase retained traces of the solonetzic stage of soil formation.

The present study seeks to improve current understanding of modern climate changes, which are considered as the consequences of the greenhouse effect caused by increasing content of the main greenhouse gases – carbon dioxide and methane. Complex studies in the land–shelf–atmosphere system across the Arctic shelf, including biogeochemical and lithological analyses of sediments across Eastern Arctic seas, are needed. The research aims to study both lithological and mineralogical sediment compositions, variability of the organic matter content (Corg), molecular and isotopic composition of carbon (δ13C) contained in the ice complex deposits (ICD) along the Laptev Sea coast (Cape Muostakh). Samples of modern bottom sediments obtained during the expedition of 2015 in the south-eastern part of the Laptev Sea were investigated. Methods used in the present study include GC-MS analysis, pyrolysis, isotope analysis, X-ray phase analysis followed by further numerical processing and interpretation. Results. The mineralogical composition of the clay fraction has been studied, and the distribution of clay minerals has been established. The features of molecular and isotopic Corg composition are revealed. Initial results on the hydrocarbon source of ICD- Corg, which dominates in the shallow part of the East Siberian Arctic shelf, are obtained. Pyrolysis and GC-MS data are highly correlated reflecting complex biogeochemical processes occurring during the Corg transformation at the various stages of lithogenesis. In addition, the study provides preliminary estimates of the light hydrocarbons generation potential for the Corg contained in the sediments.

Aim. Copper-nickel deposits are located all over the world. A large amount of nonmetalliferous raw materials is formed, when they are developed. It moves into dumps and creates environmental risks for the environment. In the dumps magnesium-containing rocks prevail, which must be disposed of. The purpose of the work is to study the possibility of their use in the production of building materials. Methods. The chemical analysis was carried out by gravimetry, photometry, and atomic-absorption spectroscopy. The mineral composition was studied using X-ray phase analysis. The mechanical parameters were determined on a test hydraulic press. Results. It is established that the crushed stone from magnesiumbearing rocks is of high quality and can be used as a large aggregate in the production of concretes. It is shown that the concrete, containing crushed stone from ultrabasic rocks - verlites show the most compression strength. The lowest values has ordinary concrete on granite crushed stone. The type of hardening conditions also affects the strength of the resulting material. Sand from the sifting of crushing rock mass has angular shape of the grains and a mineral composition as in the parent rock. This contributes to the design of a dense structure of concrete stone, which increases its strength by more than 10%. Main conclusions. The use non-metalliferous raw materials will reduce the volumes of waste rock formed during the development of mineral deposits. In this case, it is possible to obtain a finished commodity product - crushed stone from magnesium-containing rocks and sand from their crushing. This will solve environmental, economic problems, as well as produce the necessary building materials for their own needs.

Mineralogical composition of different texture fractions of Solonetz (Calcic Gypsic Endosalic Solonetz (Columnic Cutanic differentic) was studied. Inves-tigated object was located on the Borsi key plot in the northern part of the Caspian lowland (absolute height of the territory about 48 m) and developed on Early Khvalynian deposits. The profile of Solonetz is formed on coarsesilty clays and is characterized by depletion of silt in the upper 5cm horizon. The modern pedogenesis causes eluvial-illuvial distribution of silt fraction along the profile and the different ratio of mineral phases: 1) trioctahedral illites prevail in the SEL horizon, which indicates the process of illitization; 2) the upper natric horizon differs from the underlying ones by the predominance of labile minerals with the segregation of smectite packages. This pattern is associated with the process of lessivage, which occurs as the forming of clayey coatings. According to the mineralogical composition, some stratification of the soil-forming material is noted: in the upper part of the profile there was an increased content of illite of tridioctahedral type and mixed-layer minerals in comparison with the lower horizons. Comparing to the accumulative-calcareous horizons BCA and BSN3s the calcareous (Cca,s) horizon has a higher content of chlorite and kaolinite with perfect structure. The distribution of clastogenic minerals along the Solonetz profile in silt fractions and ≥ 10 μm has a weak disordered variation. With the increase of fractions sizes, an increase in the content of quartz, feldspars, plagioclases was marked. Also, the decrease of micas due to their more active disintegration during the pedogenesis was revealed.

The distribution of clay minerals of the fraction less than 1 micron, extracted from typical, alkaline, podzolized agronomic black earths, depends on the type of soil, lithology of soil-forming rocks and relief. The silt fraction of agrochernozems developed on the quaternary loess-like heavy loam consists of smectite phase, represented by complex disordered mica-smectite formations, di-trioctahedral mica, kaolinite, chlorite. Agroblack soils formed on sediments in which include Neogene eluvium, contain a smectite phase represented by montmorillonite itself and badelyte with clinoptylolites in it. Erosion-resistant the material is represented by rounded aggregates, the structure of which was determined by micromorphological analysis. In the composition of micaceous micaceous fraction, extracted from this material, is dominated by micaceous mectritic formation. The conclusion is made about the demolition of the most valuable fertility of aggregated material - product of interaction smectite phase with organic matter.