Based on artificial freezing engineering practice, the comprehensive technology is suggested to realize safe and fast rock cross-cut coal uncovering, which mainly includes four steps of drilling, water injection wetting coal, gas drainage, liquid nitrogen into seam. Freezing test carried out obtain cooling curves, comparing results, numerical inverse method applied determine thermal conductivit...

Possible issues during mining of the upper coal seam in old goaf nearby seams, including step subsidence, gas overflow goaf, and roadway around rock fragmentation. Using Hanjiawa Coal Mine’s mining, which takes place 28 m above working face lower seam, as research’s focal point. The paper focuses on self-stability pillar failure form floor, roof caving rule bearing capacity interlayer strata us...

In coal seam gas (CSG) wells, water is periodically removed from the wellbore in order to keep the bottom-hole flowing pressure at low levels, facilitating the desorption of methane gas from the coal bed. In order to calculate gas flow rate and further optimize well performance, it is necessary to accurately monitor the liquid level in real-time. This paper presents a novel method based on auto...

In order to solve the problem of surrounding rock control in soft coal seam roadway, taking centralized return airway No. 2 Liangdu Coal Industry as research background, mechanical conditions roadway were analyzed by means field investigation, mechanics experiment and numerical simulation. The design principles support put forward: high strength anchor cable support, preload stiffness support. ...

Some coal seams in southeast BC are characterized by fine size consist and a moderate amount of inherent ash. Mining strategies and wash plants are designed to handle these coals but sometimes seams are mined, that are unusually difficult to clean. Samples of a number of such coals were acquired and studied. Samples come from a mine and an adjacent property ( samples GC in tables) near Sparwood...

Coal exploration and mining in extensively drilled and sampled coal seams can benefit from 3D statistical facies interpolation. Starting from closely spaced core descriptions, and using interpolation methods, a 3D optimum and robust facies distribution model was obtained for a thick, heterogeneous coal seam zone deposited in the non-marine As Pontes basin (Oligocene-Early Miocene, NW Spain). Se...

Organic compounds in Australian coal seam gas produced water (CSG water) are poorly understood despite their environmental contamination potential. In this study, the presence of some organic substances is identified from government-held CSG water-quality data from the Bowen and Surat Basins, Queensland. These records revealed the presence of polycyclic aromatic hydrocarbons (PAHs) in 27% of sa...