Justification of a Method for Determination of Gas Content in Coal Seams to Assess Degasification Efficiency

摘要

The article presents a set of methods to assess gas liberation from coal substance on stages of drilling and coal core extraction, free gas discharge and gas diffusion from coal in the course of its activation by mechanical disturbance. The issues of their use in the mining industry are discussed. The analysis of ways to measure the methane desorption rate (volumetric method) and reservoir properties of coal is provided. Patterns of quantitative and qualitative distribution of methane within a coal rock massif are considered for the purpose of getting full information about fluctuation of volume and relative portion of residue gas under the impact of weathering and mining operations. A novel approach is suggested for the determination of gas content in coal seams to assess the effectiveness of degasification, to specify ventilation schemes and parameters of mining workings as well as to establish critical depths for sudden coal and gas outbursts manifestation and power accumulation for their potential occurrence.