Amino resins crosslinked polymer gels for permeability profile control

Claim 2

A process for closing pores in a hydrocarbonaceous fluid bearing formation to obtain improved sweep efficiency during a waterflood oil recovery operation which comprises injecting a gellable composition comprising: (a) water; (b) 0.2 to 5.0 wt. percent of a cross linkable polymer which is a member selected from the group consisting of xanthan biopolymers, heteropolysaccharide S-130, poly (acrylamide-co-acrylamido-2-methyl-propanesulfonate), and acrylamide modified polyvinyl alcohol; and (c) 0.02 to 50.0 wt. percent of a partially methylated aminoplast resin which cross links with said polymer thereby forming a gel in the absence of a salt which is acid generating upon the application of heat which gel is of a strength sufficient to close pores in one or more permeable zones of said formation.

Claim 3

The process as recited in claim 1 wherein said resin is a member selected from the group consisting of melamine-formaldehyde, urea formaldehyde, ethylene urea formaldehyde, propylene urea formaldehyde, triazone, uron, and glyoxal.

Claim 4

The process as recited in claim 1 wherein the ratio of polymer to said resin required for gelation is from about 10:1 to about 1:10.

Claim 5

The process as recited in claim 1 wherein said gel is formed under salinity concentrations encountered in an oil reservoir.

Claim 6

The process as recited in claim 1 wherein said gel is of a stability sufficient to withstand high temperatures encountered in an oil reservoir for at least three months.

Claim 7

The process as recited in claim 1 wherein said gel is unaffected by carbonate, bicarbonate, and sulfate anions encountered in an oil reservoir.

Claim 8

The process as recited in claim 1 wherein said resin can condense to form a cured resin.

Claim 9

A process for closing pores in a hydrocarbonaceous fluid bearing formation to obtain improved sweep efficiency during a carbon dioxide oil recovery operation which comprises injecting a gellable composition comprising: (a) water; (b) 0.2 to 5.0 wt. percent of a cross linkable polymer which is a member selected from the group consisting of xanthan biopolymers, heteropolysaccharide S-130, poly (acrylamide-co-acrylamido-2-methyl-propanesulfonate), and acrylamide modified polyvinyl alcohol; and (c) 0.02 to 50.0 wt. percent of a partially methylated aminoplast resin which cross links with said polymer thereby forming a gel in the absence of a salt which is acid generating upon the application of heat which gel is of a strength sufficient to close pores in one or more permeable zones of said formation.

Claim 10

A process for closing pores in a hydrocarbonaceous fluid bearing formation to obtain improved sweep efficiency during a carbon dioxide oil recovery operation which comprises injecting a gellable composition comprising: (a) water; (b) 0.2 to 5.0 wt. percent of a cross linkable polymer which is a member selected from the group consisting of xanthan biopolymers, heteropolysaccharide S-130, poly (acrylamide-co-acrylamido-2-methyl-propanesulfonate), and acrylamide modified polyvinyl alcohol; and (c) 0.02 to 50.0 wt. percent of a partially methylated aminoplast resin which cross links with said polymer thereby forming a gel in the absence of a salt which is acid generating upon the application of heat which gel is of a strength sufficient to close pores in one or more permeable zones of said formation.

Claim 11

The process as recited in claim 8 wherein said resin is a member selected from the group consisting of melamine-formaldehyde, urea formaldehyde, ethylene urea formaldehyde, propylene urea formaldehyde, triazone, uron, and glyoxal.

Claim 12

The process as recited in claim 8 wherein the ratio of polymer to said resin required for gelation is from about 10:1 to about 1:10.

Claim 13

The process as recited in claim 8 wherein said gel is formed under salinity concentrations encountered in an oil reservoir.

Claim 14

The process as recited in claim 8 wherein said gel is of a stability sufficient to withstand high temperatures encountered in an oil reservoir for at least three months.

Claim 15

The process as recited in claim 8 wherein said resin can condense to form a cured resin.

Claim 16

The process as recited in claim 8 wherein said gel is unaffected by carbonate, bicarbonate, and sulfate anions encountered in an oil reservoir.