FIELD: mining.
SUBSTANCE: method of recirculation of drilling fluid medium in borehole system consists in drilling of substantially vertical borehole (12) from surface (14) into underground zone (15) and drilling of jointed borehole (30) from surface into underground zone. The jointed borehole is set off horizontally from the substantially vertical borehole on the surface and crosses the latter in the joining point near the underground zone. The method also consists in drilling of drainage cavity (50) from the point of borehole joining into the underground zone and supply of the drilling fluid via a drilling tube while passing through the drainage cavity. The method further comprises liquid supplied to the substantially vertical borehole via a pipeline. Fluid mixture rises to the surface via the substantially vertical borehole beyond the pipeline. The fluid mixture comprises the drilling fluid after its flowing out the drilling tube.
EFFECT: facilitates more extensive development and utilisation of methane deposits in coal beds.
49 cl, 5 dwg
