Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
77 words
In the method for recovering oil from a heterogeneous subterranean reservoir in which there is injected into the reservoir through an injection well in communication therewith a micellar solution, an aqueous plug-forming composition containing a polyvalent cation which is injected before the injection of all of the micellar solution, and an aqueous flooding medium, the improvement which comprises: producing the injection well after injection therein of the plug-forming composition to remove from the reservoir unreacted polyvalent cations.
Claim 2
Dependent Claim
77 words
In the method for recovering oil from a heterogeneous subterranean reservoir in which there is injected into the reservoir through an injection well in communication therewith a micellar solution, an aqueous plug-forming composition containing a polyvalent cation which is injected before the injection of all of the micellar solution, and an aqueous flooding medium, the improvement which comprises: producing the injection well after injection therein of the plug-forming composition to remove from the reservoir unreacted polyvalent cations.
Claim 3
Dependent Claim
29 words
The method defined in claim 1 wherein the well is produced until the concentration of unreacted polyvalent cation in the produced fluids falls below about 25 parts per million.
Claim 4
Dependent Claim
27 words
The method defined in claim 1 wherein the well is produced at a rate of 0.1 to 1 gallon per minute for from 8 to 24 hours.
Claim 5
Dependent Claim
21 words
The method defined in claim 1 wherein the aqueous plug-forming composition is injected prior to the injection of the micellar solution.
Claim 6
Dependent Claim
37 words
The method defined in claim 1 wherein the aqueous plug-forming composition is injected following the injection of a first portion of the micellar solution and prior to the injection of a second portion of the micellar solution.
Claim 7
Dependent Claim
30 words
The method defined in claim 1 wherein the micellar solution is selected from the group consisting of substantially anhydrous soluble oil, water-containing soluble oil, water-external microemulsion and aqueous micellar solution.
Claim 8
Dependent Claim
22 words
The method defined in claim 1 wherein the aqueous plug-forming composition contains alkali metal or ammonium hydroxide, carbonate, bicarbonate, silicate or phosphate.
Claim 9
Dependent Claim
14 words
The method defined in claim 7 wherein the aqueous plug-forming composition contains sodium silicate.
Claim 10
Dependent Claim
37 words
The method defined in claim 7 wherein the aqueous plug-forming composition contains an alkaline alkali metal silicate having a molar ratio of M 2 O/SiO 2 of 1 and above, wherein M is an alkali metal atom.
Claim 11
Dependent Claim
21 words
The method defined in claim 1 wherein the aqueous plug-forming composition contains cross-linked polyacrylamide, hydraulic cement or delayed action silica gel.
Claim 12
Dependent Claim
30 words
The method defined in claim 1 wherein the polyvalent cation is selected from the group consisting of aluminum, calcium, cobalt, nickel, copper, mercury, silver, lead, chromium, zinc, cadmium and magnesium.
Claim 13
Dependent Claim
12 words
The method defined in claim 11 wherein the polyvalent cation is calcium.
Claim 14
Dependent Claim
130 words
In the method of recovering oil from a highly heterogeneous subterranean reservoir containing strata of widely varying permeabilities in which there is injected into the reservoir through an injection well in communication with the said strata a micellar solution, an aqueous plug-forming composition containing a polyvalent cation which composition enters the more permeable strata and reduces the permeability of these strata so that all strata in the reservoir are more uniform in permeability, and an aqueous flooding medium, the improvement which comprises: producing the injection well after injection therein of the plug-forming composition and prior to the injection therein of at least a portion of the micellar solution, said production being carried out at a rate for a length of time sufficient to remove from the reservoir unreacted polyvalent cations.
Claim 15
Dependent Claim
130 words
In the method of recovering oil from a highly heterogeneous subterranean reservoir containing strata of widely varying permeabilities in which there is injected into the reservoir through an injection well in communication with the said strata a micellar solution, an aqueous plug-forming composition containing a polyvalent cation which composition enters the more permeable strata and reduces the permeability of these strata so that all strata in the reservoir are more uniform in permeability, and an aqueous flooding medium, the improvement which comprises: producing the injection well after injection therein of the plug-forming composition and prior to the injection therein of at least a portion of the micellar solution, said production being carried out at a rate for a length of time sufficient to remove from the reservoir unreacted polyvalent cations.
Claim 16
Dependent Claim
30 words
The method defined in claim 13 wherein the injection well is shut in following injection of the plug-forming composition for a period of time sufficient for a plug to form.
Claim 17
Dependent Claim
29 words
The method defined in claim 13 wherein the well is produced until the concentration of unreacted polyvalent cation in the produced fluids falls below about 25 parts per million.
Claim 18
Dependent Claim
27 words
The method defined in claim 13 wherein the well is produced at a rate of 0.1 to 1 gallon per minute for from 8 to 24 hours.
Claim 19
Dependent Claim
21 words
The method defined in claim 13 wherein the aqueous plug-forming composition is injected prior to the injection of the micellar solution.
Claim 20
Dependent Claim
37 words
The method defined in claim 13 wherein the aqueous plug-forming composition is injected following the injection of a first portion of the micellar solution and prior to the injection of a second portion of the micellar solution.
Claim 21
Dependent Claim
30 words
The method defined in claim 13 wherein the micellar solution is selected from the group consisting of substantially anhydrous soluble oil, water-containing soluble oil, water-external microemulsion and aqueous micellar solution.
Claim 22
Dependent Claim
22 words
The method defined in claim 13 wherein the aqueous plug-forming composition contains alkali metal or ammonium hydroxide, carbonate, bicarbonate, silicate or phosphate.
Claim 23
Dependent Claim
14 words
The method defined in claim 20 wherein the aqueous plug-forming composition contains sodium silicate.
Claim 24
Dependent Claim
37 words
The method defined in claim 20 wherein the aqueous plug-forming composition contains an alkaline alkali metal silicate having a molar ratio of M 2 O/SiO 2 of 1 and above, wherein M is an alkali metal atom.
Claim 25
Dependent Claim
21 words
The method defined in claim 13 wherein the aqueous plug-forming composition contains cross-linked polyacrylamide, hydraulic cement or delayed action silica gel.
Claim 26
Dependent Claim
30 words
The method defined in claim 13 wherein the polyvalent cation is selected from the group consisting of aluminum, calcium, cobalt, nickel, copper, mercury, silver, lead, chromium, zinc, cadmium and magnesium.
Claim 27
Dependent Claim
12 words
The method defined in claim 24 wherein the polyvalent cation is calcium.