Abstract: To control the process of underground gasification of a coal bed with due provisions for the natural geological and mining conditions, in the disclosed method the rate of gassing-out the coal bed is selected from the following expression: ##EQU1## WHERE W is the amount of water flowing into the gasification zone, m.sup.3 /hour;I is the amount of coal gassed out per unit of time, tons/hour (the intensity of the process);Q.sub.h.sup.r is the combustion heat of the gas, kcal/m.sup.3 ;v.sup.r is the yield of gas from 1.0 kg of coal, m.sup.3 ;Q.sub.h.sup.y is the lowest combustion heat of coal, kcal/kg;m is the thickness of the coal bed, in meters.

Abstract: A method of mine-less connection of wells for underground gasification by the filtrational fire connecting technique is intended primarily for forming a single unitary gasification channel for underground gasification of coal, oil shale and oil-bearing beds. In the disclosed method of connecting wells or boreholes drilled for underground gasification, the coal bed is ignited in one of the wells situated in the direction of formation of the unitary gasification channel. After a center of combustion has been set in this well, an air blast is directed at a permanent flow rate into the well with which the connection is to be effected. The pressure of the air blast charged into the well is measured, and when the pressure drops considerably, an air blast is charged for connection purposes into the next successive well in the direction of formation of the gasification channel.

Abstract: A method of processing recently bored channels when putting into operation an underground gas generator (underground gasifier), consisting, on the one hand, in forced air blowing and, on the other hand, in taking away hot gases, is characterized by determining the magnitude of the hydrostatic pressure by measuring the hydrostatic column of underground waters in a vertical direction from the point at which air is forced into the well to the level of the underground waters, and adjusting the outlet section of the gas discharging wells. This permits maintaining in the boring channel a pressure at a level which is not less than that produced by the hydrostatic column to preclude an inflow of underground waters to the channel being processed. The temperature in the channel is raised at a rate from about 80.degree. C to about 100.degree. C per hour up to at least 500.degree. C.

Abstract: The method connecting wells by hydraulic-fracturing of a mineral bed, primarily for connection of wells in underground gasification of coal beds; using hydraulic-fracturing of a bed is effected intermediate a source-well into which a liquid is pumped under pressure and a well in the required direction; the head of the well with which connection is to be effected is sealed, whereas the heads of the wells, with which connection is undesirable, are opened; the liquid is pumped into the source-well under a pressure sufficient for initiating hydraulic-fracturing; the pressure in the well with which the source-well is to be connected is measured, and the moment the pressure in this well attains the hydraulic-fracturing value, the head thereof is immediately opened; upon the formation of a hydraulic fracturing fissure, the latter is flushed with the liquid; the method provides for building up a hydraulic-fracturing pressure in the well with which connection of the source-well is to be effected and thus controlling t

Abstract: A heater includes coaxially arranged an external heat radiating shell, a central gas fuel tube and an intermediate perforated air conducting tube, from inside of which air flows into a combustion chamber.A tubular partition is provided with the space in between the air conducting tube and the central gas fuel tube, whereby the initial air flow blowing around and lengthwise of the gas fuel tube is to be turned near the end of this tube to pass to the perforated walls of the air conducting tube.