METHOD FOR LIQUIDATION OF TECHNOGENIC DEPOSITS OF HYDROCARBON GASES IN SURFACE-ADJACENT MASSIFS OF ROCK AT HYDROCARBON DEPOSITS Russian patent published in 2005 - IPC

FIELD: oil and gas industry.

SUBSTANCE: method includes determining depth of deposit collector and main crack directions of rock massif in contour of technogenic deposit and also points of their intersection. On contour of closest deposit center mark is placed, in closest to said mark point of intersection of main crack directions central well is drilled to depth of collector of deposit, and its mouth is equipped with special device for draining gas. Then around it, with consideration of previously determined main crack directions, at least four unloading wells are additionally drilled around central well. In each drilled well around central well starting concentration of hydrocarbon gases is determined, in particular concentration of methane and its homologues. Into central well inert gas is fed with concurrent determination of concentration of methane at mouth of unloading wells, while feeding is carried on until reaching lower limit of explosion-hazardous methane value at mouth in at least one unloading well. After that a well is selected from row of unloading wells with highest concentration of methane, function of central well is transferred to it and through this unloading well inert gas is fed, filling methane concentration chambers on mouth of remaining wells. Said process of transferring of function of central well to other unloading wells is repeated until reaching concentration of methane at mouth of all drilled wells no higher than lower limit of explosion-hazardous value for that gas. After that feeding of inert gas is stopped. In each previously drilled well at central area concentration of methane and its homologues is measured anew. If its value is higher than lower limit of explosion-hazardous value at least in one of said wells, cycle for feeding inert gas is repeated according to above-mentioned scheme until reaching concentration of methane and its homologues in wells at central area no higher than upper limit of explosion-hazardous value for these gases. After that all previously drilled wells are closed and left for performing periodical control over concentrations of natural gases in collector.

EFFECT: higher efficiency.

3 cl, 1 ex, 4 tbl