Bryk D. Improving the level of environmental safety in thermochemical processing of substandard carbon-containing raw materials

The thesis paper deals with substantiation and development of scientific bases of increase of ecological safety at thermochemical processing of substandard carbonaceous raw materials in the context of the purposes of sustainable development of Ukraine and changes of environment, and also to development of ecological ways of reception of power gases and chemical products from substandard coal including ongraund and underground conditions. Based on a study of Ukraine's sustainable development goals for energy, resource management and environmental change, it is shown that environmental security in the energy sector is a necessary condition for achieving sustainable socio-economic development of the country as a whole. In the work on the example of Chervonohrad mining district of Lviv region the ecological risks and impact on the environment of coal technogenic objects are investigated and systematized. It has been established that the greatest negative impact on the environment is caused by the emission of mine methane, dumps of mine rock - heaps and residues of coal mining and coal beneficiation. The review of known methods of thermochemical processing of carbonaceous raw materials showed that the gasification process, which allows to process various substandard fuel resources in terrestrial and underground conditions, is the most promising for improving environmental safety and environmental modernization of the country's coal industry. Development of theoretical principles of ecological thermochemical processing of substandard carbonaceous raw materials includes determination of equilibrium composition and thermophysical properties of gasification products of solid carbonaceous raw materials by thermodynamic method, modeling of solid fuel combustion process in coal seam conditions, determination of thermobaric parameters. methane. On the basis of the developed theoretical bases of thermochemical processing of carbon-containing raw materials and calculation of parameters of processes of transformation of individual chemical compounds the laboratory installation on which experimental researches of process of gasification of high-ash sapropelite coal and Carpathian menilitic shales volume with the receipt of valuable chemical products - resin and combustible gas, and shale gasification is unstable, is incomplete with attenuation. Ten developed and patented new methods and devices of thermochemical processing of substandard carbon-containing raw materials for use in terrestrial and underground conditions, which differ in energy efficiency and environmental friendliness of thermochemical processes and the quality of the obtained products, are presented. Physico-chemical methods of obtaining the liquid phase - extract from substandard carbon-containing raw materials are considered and systematized. Theoretical analysis of potential methods of extraction of lignites, coal of different stages of metamorphism, Carpathian menilitic shales and coal pitch by means of organic and inorganic solvents is carried out. It is shown that the methods of extraction and depolymerization of substandard carbonaceous raw materials can be the basis of new environmental technologies with the subsequent production of synthetic liquid fuel. The analysis of environmental risks when using the technology of underground coal gasification showed that, in comparison with the mine method of coal mining, the risks of contamination of the fertile soil layer - minimal, surface and groundwater and air - are insignificant. On the basis of a set of mining-geological and chemical-technological criteria for the selection of coal seams for the application of underground gasification technology, the coal basins of Ukraine have been studied. It is shown that the potential of coal deposits suitable for underground gasification in Ukraine exceeds 2,5 billion tons. A technical and economic evaluation of the cost of obtaining combustible products by the method of underground gasification of coal, which confirmed the cost-effectiveness of its implementation. In general, the paper substantiates and develops the scientific principles of improving environmental safety in thermochemical processing of substandard carbon-containing raw materials.