Conditions of the coal seams bedding at the mines of Kuzbass and Vorkutskoye deposits, their natural methane content and coal grades are studied in the article. Performance of shearers and the natural degassing effect of the second working on the change in the methane content of the massif in the coal mining zone are evaluated.
Dependence is established concerning the coefficient of coal seams natural degassing on the thickness of the mined seam. The influence of natural and mining-technical factors on the efficiency of second working and degassing parameters were studied. The relationship is revealed between the natural methane content of coal seams with the yield index of the volatile substances contained in the coals of various grades. The relationship is defined related to the intensity of the initial methane release from the coal mass to the reservoir degassing wells depending on the natural methane content of the reservoir with the outgoing air flow. Comparison of the data obtained during geological exploration works, and the predicted values calculated based on the identified dependencies showed their good convergence.
The dependences were revealed concerning the zones of intense methane release in the degassing wells on the thickness of the inter-layer of the unloaded adjacent layers in the roof and soil of the working layer in the process of moving the working face. This information allows to select the optimal mode of wells functioning for extracting methane-air mixtures suitable for utilization in the unexplored mine fields.
Recommended coefficients of degassing of the methane emission sources were determined for ensuring the planned productivity of the working face with the view to ensure its safety on the gas factor.