METHOD OF UNDERGROUND FIRE CONTROL Russian patent published in 2000 - IPC

FIELD: mining; applicable in control of underground fires in coal mines with widely developed network of workings. SUBSTANCE: method includes drilling from far approaches of guard-fire holes from workings into rocks towards workings encircled by fire with orientation of their faces above these workings; performance of temperature-gas control in the course of hole drilling; cooling of detected zones of rocks with elevated temperatures by injection of water through holes with its alternation with supply of fire-extinguishing substances through the same holes; simultaneous stage cooling of coal-rock mass round working fully encircled by fire. For this purpose, prospecting hole is drilled in roof of this working at bulkhead. During drilling of prospecting hole, state of rock mass, its temperature and concentration of gases in it are monitored over entire hole length. Detected zones with elevated temperature of rocks are cooled with water through hole, and bulkhead is opened. The same procedure is used in opening of the next bulkheads up to that bulkhead in whose region of location, data of hole drilling show that further performance of these operations is of high risk. Then, additional prospecting holes are drilled in roof, sides and floor of working. Results obtained in prospecting drilling serve as a base for assessment of conditions: either further continuation of bulkheads opening or beginning of strengthening of coal-rock mass round working on district B. For strengthening of coal-rock mass, series of holes are drilled under protection of bulkhead for supporting curbs. After drilling and casing of holes and preliminary cooling of mass, strengthening and grouting mortars are injected into mass to form supporting curbs and strengthened zone in coal-rock mass round working of strengthened district. Drilled between the first and second curbs are guard holes for cooling of coal-rock mass of district with nonopened bulkheads. Then, built-in central part of district is additional blasting bulkhead and space is left for formation of temperature absorption chamber. Bulkhead is provided with manhole, sampling tube, thermocouple, branch pipes for connection of drenches and holes to water supply line. Should temperature and gas concentration rise above permissible values, coal-rock mass is cooled with water on district of working nonopened bulkheads through water and fire-extinguishing composition supply holes. Upon normalization of conditions on district, described complex of operations engaged in bringing under control and extinguishing of fire is repeated on this district with maximum possible approach to fire seat. Using the above procedure, coal-rock mass round the other workings caught by fire is subjected to cooling too. In workings adjacent to fire seat but not encircled by fire, prospecting holes are drilled in roof rocks for detection of zones with elevated temperatures of rocks and their subsequent cooling with water. EFFECT: stage-by-stage cooling of coal-rock mass round workings adjacent to fire seat and encircled by fire and simultaneous cooling of rock mass in region of these workings. 5 cl, 14 dwg