Coal is an important fossil fuel and will also be for the next decades [1]. The only way to achieve the challenges faced by the coal industry is to reduce production costs by improving productivity. Improvement of productivity has become an important goal for today’s coal industry in the race to increase price competitiveness. In recent years, underground mining method is becoming popular becau...

Land surface deformation can be caused by underground mining activities. The maximum subsidence normally occurs directly above the location of the excavation of the coal seam. In the case where the longwall mining technique is applied, the magnitude and shape of the subsidence bowl are constrained by the longwall structure (pillar). This paper describes the use of satellite radar interferometry...

Hydrocarbon wells drilled vertically through longwall coal pillars are vulnerable to severe deformation and potential failure as a result of underground coal mining. The lithology of the host rocks play a critical role in well stability. In this study, a two dimensional finite element method is employed to investigate the horizontal shear offset, vertical delamination, and compression at the we...

Compared to opencut mining, underground coal mining is more common in Australia due to its lesser impact on the environment. Although there are several underground mining methods, such as the longwall, pillar, bord, and miniwall, longwall mining is the most commonly used method due to its high efficiency. However, longwall mining does lead to significant ground subsidence. Mining subsidence is ...

Noise is one of the most pervasive health hazards in mining. A compilation of Mine Safety and Health Administration (MSHA) noise survey data for Fiscal year 1990 shows that approximately 40% of the total samples taken for longwall occupations exceeded the Permissible Exposure Limit (PEL) of 100% [Gigliotti et al. 1991]. In order to properly determine workers’ exposures on longwall coal mining s...

This paper presents technical and application aspects of a new software suite, MCP (Methane Control and Prediction), developed for addressing some of the methane and methane control issues in longwall coal mines. The software suite consists of dynamic link library (DLL) extensions to MS-Access written in C++. In order to create the DLLs, various statistical, mathematical approaches, prediction ...

Based on techniques of close upper protective coal-rock layer mining, relieved gas extraction, and underground gangue washing-discharging-backfilling, this paper initiates the concept of mixed fully-mechanized coal mining, which combines a solid backfilling method and a caving method (hereinafter referred to as “backfill and caving mixed mining”). After the principle and key techniques are intr...

Longwall mining is the only technically proven and established method worldwide for coal extraction at greater depth. In this paper, 2D plane strain finite element models of longwall panels are developed and analyzed to understand the interaction of hydraulic powered support with surrounding rock strata. Based on Indian geomining conditions, finite element models are developed including the str...

Effective gas management is vital to the success of the longwall mining in the Bulli seam, in the Southern Coalfield, Sydney Basin, NSW, Australia. The evolution of gas drainage methods and practices are discussed with respect to gas type, gas drainage lead time and prevailing geological conditions. Both underground to inseam drilling and surface to inseam drilling techniques are described at b...

Mining subsidence associated with longwall extractions beneath significant natural features such as rivers and streams in the Southern Coalfield of New South Wales has posed risks to the natural environment. In this paper, a case study is presented showing the methodology in two-dimensional UDEC (Itasca 2006) modeling for mining induced subsidence around river valley, taking advantage of the di...