Abstract:

The underground process of hard coal production, due to the mining and geological conditions in which it is carried out, is exposed to various types of natural hazards. Based on experience and the analysis of mining event reports, it can be concluded that one of the most dangerous threats to this process is the methane hazard. The effects of the events related to the occurrence of methane in mines are very large, both for the staff, machines and devices and the entire infrastructure of mining excavations. These events also cause huge financial losses and adversely affect the efficiency of the entire process. Therefore, it is necessary to conduct research aimed at developing effective methods of limiting the possibility of such events (ignition and explosion of methane). The solution presented in this paper is part of the area of ​​activities aimed at improving operational safety by limiting the methane hazard. It covers the use of model tests to identify places where dangerous methane concentrations may occur and the values ​​of these concentrations in mining excavations. The use of the finite volume method for analysis allows for the precise mapping of the geometry of the studied regions and the physico-chemical conditions prevailing in them.

The article presents the research methodology developed and the results obtained for one of the mine workings. The presented analyzes were carried out for a spatial model of the longwall area using the CFD method. The actual dimensions of workings as well as measurement data concerning the concentration of methane and ventilation parameters were taken into account. It should also be emphasized that the data used in the model are the result of measurements in real conditions, which is of great importance for the reliability and practical significance of the results obtained. The obtained results are therefore a current assessment of the distribution of methane concentration in the studied area, which can be used practically. The presented work is therefore an example of the practical application of advanced computational tools to study potentially dangerous ventilation phenomena in mining. The use of advanced structural models and numerical simulation also enables the study of these models for many potential variants of changes in boundary conditions. Therefore, the developed method and the results obtained have, apart from the cognitive values, also of great practical importance.