The article deals with the problem of rational use of waste of enterprises for the production of silicate cement. Currently the production gliezh waste (burnt clay) does not find its application and is disposed of. A method of obtaining a sorbent based on the gliezh waste is suggested, the aluminium oxide content in which ranges from 15 to 40 % and silicon oxide – from 55-75 %. Pre-burnt clay is treated with sulphuric acid, and then calcined in a muffle furnace at t = 300 °C. The resultant sorbent has high rates of wastewater treatment from heavy metals.

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THE PURPOSE. Consider the combustion process of two coals of different degrees of metamorphism and their mixtures using thermogravimetric analysis based on the change in mass and the rate of change in mass during the heating of fuels. Determine the main characteristics of fuels and the combustion process (temperature of ignition and burnout of the coke residue). Determine the tendency to slagging of coal mixtures. METHODS. When solving the tasks, the thermogravimetric method (TGA). RESULTS. The article provides a brief overview of the combustion of non-design fuels at thermal power plants. The results of technical and elemental analysis of Chernogorsk bituminous coal and Balakhta brown coal are presented. A technique for determining the ignition temperature and burnout of the coke residue is described. The thermograms of the combustion process of two coals of different degrees of metamorphism and their mixtures are presented. The main characteristics of their combustion have been determined. A qualitative analysis of the surface of fuel particles for the presence of pores and cracks is shown. The calculation of the tendency to slagging of coal mixtures has been carried out. CONCLUSION. Thermogravimetric analysis showed an earlier ignition of the Balakhta brown coal in comparison with the Montenegrin bituminous coal. With an increase in the proportion of Balakhta coal in the coal mixture, the profile of the combustion curves shifts to the region of lower temperatures. The addition of 25% Balakhta coal reduces the ignition temperature of Chernogorsk coal by 16%, with an increase in the proportion of Balakhta coal in the mixture, the ignition temperature does not change. Balakhta coal has a high tendency to slagging furnace walls, in contrast to Chernogorsk coal, therefore, an increase in its mass fraction in the coal mixture increases the tendency to slagging furnace screens.

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One of the sources of environmental pollution with hazardous substances, primarily heavy metals, is the electroplating industry. The prevention of pollution of water bodies with wastewater containing heavy metal ions is closely related to reducing the consumption of fresh water for the technological needs of production and to reducing the amount of effluent. One of the solutions to this problem is to create low-waste and waste-free environmentally safe technological processes of wastewater treatment using treated effluents in the recirculation system, which reduces the negative impact on the environment. The results of studying the sorption properties of the natural modified mineral Akdolit-Gran prove a high efficiency of this sorption filling when conditioning electroplating shop effluents contaminated with a complex of heavy metals. Taking into account a relatively low cost of this natural mineral, Akdolit-Gran has the advantages in terms of its economic feasibility, plus the high degree of extraction of metals using this sorbent together with its low consumption allows designing recirculation systems for industrial enterprises meeting the requirements for physical and chemical parameters of service water