Process for recovering hydrocarbons from solid materials

Claim 1

IN A PROCESS FOR THE RECOVERY OF LIQUID HYDROCARBONS FROM A SOLID HYDROCARBONACEOUS MATERIAL INVOLVING RETORTING SAID MATERIAL IN A CONFINED REACTION CHAMBER FILLED THEREWITH, THE IMPROVEMENT COMPRISING ESTABLISHING A BURNING ZONE IN SAID MATERIAL AT ONE END OF SAID CHAMBER, THEREAFTER SUPPLYING FROM THE END OF SAID CHAMBER OPPOSITE SAID BURNING ZONE THE OXYGEN REQUIRED TO SUSTAIN THE BURNING OF SAID MATERIAL, CONTINUING THE INTRODUCTION OF OXYGEN UNTIL SAID BURNING ZONE HAS TRAVELLED TO AN INTERMEDIATE POINT IN SAID CHAMBER, NEXT ADDING CONCURRENTLY FROM SAID OPPOSITE END OXYGEN AND SAID MATERIAL IN AN AMOUNT AND IN A RATIO SUCH THAT SAID BURNING ZONE REMAINS SUBSTANTIALLY AT SAID INTERMEDIATE POINT, AND THE PORTION OF SAID MATERIAL MOVING THROUGH SAID CHAMBER BETWEEN SAID OPPOSITE END AND SAID BURNING ZONE REMAINS UNBURNED, WHEREBY THE HYDROCARBONS THUS LIBERATED ARE PERMITTED TO REMAIN IN CONTACT WITH THE RESULTING ASH FOR AN APPRECIABLE PERIOD OF TIME TO EFFECT THERMAL CRACKING OF SAID HYDROCARBONS, AND WITHDRAWING ASH AND LIQUID HYDROCARBONS FROM THE END OF SAID CHAMBER OPPOSITE THAT INTO WHICH SAID MATERIAL AND OXYGEN ARE CONCURRENTLY INTRODUCED.