Method of in situ bitumen recovery by percolation

Claim 1

An in-situ method for producing a crude heavy hydrocarbon material from an underground carbonaceous formation, comprising the serial steps of: (a) drilling a borehole, (b) creating a void space at or near the bottom of the borehole, by a cutting means and a removing means, (c) maintaining the integrity of the formation to avoid collapse of the formation, (d) enlarging the void space in both the horizontal and vertical directions, thereby enlarging the void space in the approximate shape of a cylinder to obtain a processing chamber, (e) continuing the cutting action of step (d) with the cutting means being traversed upwardly and rotationally, thus fracturing (cutting) the underground carbonaceous formation, to the upper limits of the formation, (f) forming a slurry filling at least a portion of the fractured space in the formation, (g) inserting a pipe system comprising a bundle of spring-loaded guide tubes into the slurry, the bundle being retained in a closed position by an end cap, with each guide tube enclosing a smaller diameter flexible tube, the flexible tubes being connected to a source of liquid processing material, (h) lowering the guide tube bundle to the bottom (floor) of the slurry, (i) releasing the end cap, thus allowing the distal ends of the guide tubes to move outwardly in a generally horizontal direction normal to the axis of the bundle, thus inserting the guide tubes in the slurry, (j) introducing processing material through the inner flexible tubes, with the processing material contacting and separating, at least partially, the heavy hydrocarbon material from the remainder of the carbonaceous material, forming lighter and heavier phases in the mixture, and (k) removing the lighter phase which contains the heavy hydrocarbon material.