In the past, the impact of unfavourable natural and technological factors deteriorated the situation in the Velenje Coal Mine in terms of fire safety. By insulating the mining spaces and their walls, the number of mine fires of endogenous origin has decreased significantly. The existing technological process for the production of insulation works takes the form of preventing the contact of the air in the mine, i.e., oxygen, with the coal substance liable to spontaneous combustion. The latter is found near the mining spaces, collapsed rock formations, cracks and other voids in coal mine pillars.
Further, coal mining in the Velenje Coal Mine has progressed to an increasing depth and to areas of footwall by the quality limit, making the mining conditions more difficult and the technological conditions more complex. The mutual proximity of excavation sites also has a significant impact. Various influencing factors and technological requirements such as mechanical properties of the rock, depth, geotechnical conditions along the mining roadways, speed of progression, necessary mining roadways clearance profile and fire protection of the mining roadways affect the design and construction of mining roadways.
Nowadays, the most firmly established technology in the coal mine is the insulation and construction of mining roadways, which are supported with a TH type steel arches in combination with wooden formwork and filling the voids behind the formwork with a mixture of fly ash and water. The purpose of insulation coatings is twofold. It contributes to a better stability of the mining constructions which is reflected in a consolidated coal layer and a more even distribution of the load along the entire mining roadway. The main purpose of insulation coatings is the reduction of oxidation processes, which are the result of oxygen coming into contact with coal and thus the occurrence of fires of endogenous origin.
The paper discusses the resolution of spontaneous coal combustion in coal mines and outlines approach to addressing this issue at the Velenje Coal Mine.
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