Hydraulic mining of coal - using at least one upward entry at five degree slope

摘要

Proposed is a method of hydraulically mining coal from a panel of coal of preselected average thickness comprising: (1) Driving at least one entry upward through the panel to a predetermined terminus thereof at an average slope of at least about 5 degrees. (2) Positioning a monitor within the entry, the monitor comprising a nozzle having a diameter of from about 18 to about 40 mm adapted for pivotal motion vertically and horizontally, and being connected to means for receiving water under pressure. (3) Ejecting a jet of high pressure water at a pressure of from about 500, to about 3000 psi and at a flow rate of from about 500 to about 3000 gpm from the nozzle against the panel of coal to cut the coal from the face and break the coal into pieces. (4) Feeding the cut and broken coal to transport the coal from the face area to reduce the lumps to less than about 6 inches maximum cross-section, and (5) Feeding the coal to a fluming system positioned within the entry to enable the mined coal to be transported with the water from the nozzle as a coal-water slurry having a coal-water ratio of from about 1:2 to about 4:1.