Apparatus for recovering combustible substances from subterraneous deposits in situ

Claim 1

A TUBULAR HEATING DEVICE FOR HEATING SUB-SURFACE DEPOSITS IN THEIR NATURAL LOCATION IN THE GROUND FOR RECOVERY OF VALUABLE COMBUSTIBLE PRODUCTS IN LIQUID OR GASEOUS FORM, HEAT BEING GENERATED IN A COMBUSTION ZONE FOR FUEL INSIDE THE DEVICE WHEN POSITIONED IN SAID DEPOSIT, SAID DEVICE COMPRISING AN EXTERNAL ELONGATED TUBULAR CASING AT ITS BASE AND SIDE WALLS SEALED AGAINST THE DEPOSIT AND AT ITS TOP PROVIDED WITH AN OUTLET FOR THE PRODUCTS OF COMBUSTION PROJECTING ABOVE THE SURFACE OF THE GROUND, AND AN INTERNAL UNITARY TUBULAR STRUCTURE LOCATED CONCENTRICALLY AND LONGITUDINALLY DISPLACEABLE WITHIN SAID EXTERNAL CASING AND INCLUDING A FUEL AND OXYGEN SUPPLY CASING ADAPTED WITH ITS UPPER END EXTENDING TO THE SURFACE TO RECEIVE A MIXTURE OF FUEL AND OXYGEN, A COMBUSTION ZONE CONICAL CASING ADJACENT AND MERGING INTO THE LOWER END OF SAID SUPPLY CASING AND ADAPTED TO RECEIVE SAID FUEL AND OXYGEN MIXTURE, AND A COMBUSTION PRODUCTS TUBULAR CASING AT ITS TOP IN OPEN CONNECTION WITH SAID CONICAL CASING AND HAVING AN OPEN BASE END LOCATED IN SPACED RELATION FROM THE CLOSED BASE OF SAID EXTERNAL CASING SO AS TO PROVIDE OPEN COMMUNICATION BETWEEN SAID COMBUSTION ZONE TUBULAR CASING AND SAID EXTERNAL CASING FOR THE FLOW OF COMBUSTION FROM SAID COMBUSTION ZONE DOWNWARDS THROUGH SAID COMBUSTION PRODUCTS TUBULAR CASING AND IN COUNTER CURRENT UPWARDS THROUGH THE SPACE BETWEEN SAID INTERNAL UNITARY TUBULAR STRUCTURE AND SAID EXTERNAL TUBULAR CASING TO THE OUTLET SAID CONICAL CASING BEING CONNECTED TO SAID FUEL AND OXYGEN SUPPLY CASING AT ITS REDUCED END SO AS TO ENSURE A VELOCITY OF FLOW OF SAID MIXTURE TO THE COMBUSTION ZONE CASING GREATER THAN THE VELOCITY OF COMBUSTION IN THE ZONE OF COMBUSTION.