Process for the exploitation of bitumens containing strata by underground preparation and gasification

Claim 1

A PROCESS FOR PREPARING FOR EXTRACTION UNDERGROUN SOLID BITUMINOUS DEPOSITS IN THE PLASTIC TEMPERATURE RANGE OF THE SOLID BITUMENS COMPRISING: (A) HEATING ABOVE GROUND A HEAT TRANSFER MEDIUM COMPRISING A MIXTURE OF NON-CONDENSIBLE GASES AND CONDENSIBLE HYDROCARBONS. (B) INTRODUCING THROUGH TREATMENT BOREHOLES SAID HEAT TRANSFER MEDIUM INOT SAID BITUMINOUS DEPOSITS AT A PRESSURE ABOVE THE BREAKING PRESSURE OF SAID SOLID BITUMENS AND AT A TEMPERATURE BELOW THE SOFTENING TEMPERATURES OF SAID SOLID BITUMENS; (C) INTRODUCING COOL LIQUID LIGHT HYDROCARBONS INTO SAID TREATMENT BOREHOLES WHEREBY THE AREA AROUND SAID BOREHOLES IS COOLED; (D) INTRODUCING INTO SAID BITUMINOUS DEPOSTIS A MEMBER SELECTED FROM THE GROUP CONSISTING OG OXYGEN-RELEASING COMPOSITIONS AND EXPLOSIVES, SAID MEMBER DISSOLVED IN VOLATILE SOLVENTS AND EVAPORATING SAID SOLVENTS BY SUBSEQUENTLY INTODUCING A HOT FLUID MEDIUM WHEREBY SAID MEMBER IS PRECIPITATED IN A SOLID ACTIVATED FORM; AND (E) INTRODUCING A MIXTURE OF AIR AND HYDROCARBON VAPORS INTO SAID TREATMENT BOREHOLES AT A PRESSURE ABOVE THE BREAKING PRESSURE OF SAID SOLID BITUMENS AND IGNITING SAID MIXTURE AND SAID PRECIPITATED SOLID ACTIVATED FORM WHEREBY THE POROSITY OF SAID BITUMINOUS DEPOSITS IS MAINTAINED THROUGH SAID PLASTIC TEMPERATURE RANGE.