High Speed Production of Large Coal to Facilitate Easier and More Effective Cleaning

Track I: Power GenerationIncludes audio file (14 min.)Due to technical difficulties, the audio portion of this presentation is joined in progress.Most modern mining equipment extracts coal through grinding it from the solid using a set of rotating picks. This produces coal that is quite small in average size and generates a lot of dust in the process. The coal is also more expensive to collect and process to remove contained undesirable components. The use of high-pressure water jets as a cutting tool has been shown to provide a product that is larger in size, while con-commitantly eliminating the generation of dust (which carries with it the risk of ignition and explosion) and reducing the energy required for the mining process. Two different mining machines are described, one for use on longwall faces and one in room and pillar mines, and the potential for their development is discussed

Unconventional Gas Production from Thin Coal Seams [abstract]

Only abstract of poster available.Track I: Power GenerationThe need for enhanced natural gas production is made evident by the increasingly large percentage of the electrical power that is produced from this source (at present 25%). While this resource can be extracted from a number of sources, many of the new fields have a high decline rate, and thus increasingly unconventional sources must be developed. One such source is the natural gas found within coal beds. This Coal Bed Methane (CBM) provides only a limited reserve if the wells sunk down to the coal are drilled completely vertically, since production is a function of the length of the well that is exposed to the producing formation, since the seams of coal are often relatively thin. Where horizontal wells are drilled along the coal seam, and providing that the drill remains in the coal during the entire length of the well, much higher production levels can be achieved. Missouri S&T, in collaboration with Sandia National Laboratory, pioneered the use of high pressure water-jets for drilling such holes, and collaborated with the University of Queensland in demonstrating that wells could be drilled out to at least a kilometer in distance. Such wells also provide a path for the subsequent injection of steam and air with controlling bounding of the site, to allow the in-situ combustion of those shallow coal seams that are too thin to be mined conventionally. The producer gas generated by drilling two horizontal wells adjacent to one another (one for injection and one for extraction) can then be utilized in a surface power plant, without the environmental costs of conventional mining