Water jet coal extraction system - water jet travels over coal face in sloping gallery with slurry washed away (BR130776)

摘要

The coal mining system includes driving sloping galleries through the ground, and having a slope of about 5 deg., and employing a jet of water issuing from a nozzle which can swing horizontally and vertically, to wash away lumps of coal which are then broken up by a suitable breaking device to produce pieces of a maximum size of 15 cms, and guiding the water and coal through channels for conveying away as a slurry with a coal to water ratio of between 1 to 2 and 1 to 4. The water jet is at a pressure between 35 and 210 kg/sq. cm., preferably 130 and 155 kg/sq. cm, at a rate of between 1900 and 11,400 1/min, preferably 3,400 to 5,700 1/min. The jet may be used between two parallel galleries so that alternate washing and collection operations can be carried out.