Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
145 words
An in-situ solvent fractionation process for recovering bitumens from unconsolidated tar sands, said process consisting essentially of 1. introducing hot solvent vapors in a formation consisting essentially of a bitumen-containing tar disposed among discrete sand particles, said vapors being so composed and at such a temperature as to condense, upon contact with unfractionated tar in said formation, to form a liquid and to selectively dissolve bitumens out of said tar as a more soluble fraction, 2. allowing the resultant solution of bitumens to drain below the level at which said hot vapors contact unfractionated tar and collecting it, thereby leaving in place a less soluble bituminous fraction of said tar as an undissolved residue capable of supporting itself and the sand particles among which it is disposed; 3. removing the collected solution from said formation; and 4. recovering the dissolved bitumen content of said solution.
Claim 2
Dependent Claim
145 words
An in-situ solvent fractionation process for recovering bitumens from unconsolidated tar sands, said process consisting essentially of 1. introducing hot solvent vapors in a formation consisting essentially of a bitumen-containing tar disposed among discrete sand particles, said vapors being so composed and at such a temperature as to condense, upon contact with unfractionated tar in said formation, to form a liquid and to selectively dissolve bitumens out of said tar as a more soluble fraction, 2. allowing the resultant solution of bitumens to drain below the level at which said hot vapors contact unfractionated tar and collecting it, thereby leaving in place a less soluble bituminous fraction of said tar as an undissolved residue capable of supporting itself and the sand particles among which it is disposed; 3. removing the collected solution from said formation; and 4. recovering the dissolved bitumen content of said solution.
Claim 3
Dependent Claim
30 words
The process of claim 1 wherein the temperature and composition of said vapors are regulated so that said undissolved residue constitutes at least 5 weight percent of the unfractionated tar.
Claim 4
Dependent Claim
26 words
The process of claim 1 in which the solvent content of the solution is recovered, reheated, revaporized and reintroduced as said hot vapors to said formation.
Claim 5
Dependent Claim
25 words
The process of claim 1 in which said hot vapors comprise a hydrocarbon obtained by distilling, cracking or otherwise treating bitumens recovered from said formation.
Claim 6
Dependent Claim
31 words
The process of claim 1 in which the temperature of said hot solvent vapors upon introduction to said formation is within the range of from about 90° to about 150° C.
Claim 7
Dependent Claim
24 words
The process of claim 1 wherein the hot vapors are introduced under a small positive pressure of from about 0.5 to about 5 psig.
Claim 8
Dependent Claim
41 words
The process of claim 1 in which said solvent vapors are a mixture of vapors of an aromatic solvent which is benzene, toluene, xylene or mixtures thereof and of an aliphatic solvent which is heptane, octane, nonane, decane or mixtures thereof.
Claim 9
Dependent Claim
27 words
The process of claim 7 wherein the mole ratio of aliphatics to aromatics in said vapors is within the range of from about 60/40 to about 40/60.
Claim 10
Dependent Claim
24 words
The process of claim 1 in which said vapors are introduced to and said solution removed from said formation, both through the same bore.
Claim 11
Dependent Claim
21 words
The process of claim 9 in which said bore passes through said formation and is bottomed in an underlying impermeable strata.