Melamine/formaldehyde cross-linking of polymers for profile control

Claim 2

A process for closing pores in a more permeable zone of a hydrocarbonaceous fluid bearing formation to obtain improved sweep efficiency prior to a waterflood oil recovery operation wherein the process comprises injecting into the formation a gelable composition comprising: (a) water; (b) 0.2 to 5.0 wt. percent of a cross-linkable polymer having at least one functional group selected from a member of the group consisting of an amine, an amide, a hydroxyl, or a thiol group; and (c) 0.1 to 5.0 wt. percent of a methylol containing aminoplast resin which cross links with said polymer, thereby forming a gel of a size and strength sufficient to close pores in one or more permeable zones of said formation, said resin having amine and aldehyde in a critical mole ratio of from about 1:6 to about 1:30 respectively, which ratios are sufficient to form substantially improved stable gels for utilization in a subterranean formation during the recovery of hydrocarbonaceous fluids.

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, and triazone, uron, and glyoxal amino resins.

Claim 4

The process as recited in claim 1 wherein said polymer is a member selected from the group consisting of polyacrylamide, polyvinyl alcohol, xanthan biopolymers, Kelco S-130 biolpolymer, sodium aliginate biopolymers, poly (acrylamide-co-acrylamido-2-methyl-propanesulfonate), Phillips HE polymers, and acrylamide modified polyvinyl alcohol.

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 periods greater than 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

The process as recited in claim 1 wherein a gelation reaction which produces said gel proceeds under substantially all pH conditions.

Claim 10

A process for closing pores in a more permeable zone of a hydrocarbonaceous fluid bearing formation to obtain improved sweep efficiency prior to a cabon dioxide oil recovery operation wherein the process comprises injecting into the formation a gelable composition comprising: (a) water; (b) 0.2 to 5.0 wt. percent of a cross-linkable polymer having at least one functional group selected from a member of the group consisting of an amine, an amide, a hydroxyl, or a thiol group; and (c) 0.1 to 5.0 wt. percent of a methylol containing aminoplast resin which cross-links with said polymer thereby forming a gel of a size and strength sufficient to close pores in one or more permeable zones of said formation, said resin having amine and aldehyde in a critical mole ratio of from about 1:6 to about 1:30 respectively, which ratios are sufficient to form substantially improved stable gels for utilization in a subterranean formation during the recovery of hydrocarbonaceous fluids.

Claim 11

A process for closing pores in a more permeable zone of a hydrocarbonaceous fluid bearing formation to obtain improved sweep efficiency prior to a cabon dioxide oil recovery operation wherein the process comprises injecting into the formation a gelable composition comprising: (a) water; (b) 0.2 to 5.0 wt. percent of a cross-linkable polymer having at least one functional group selected from a member of the group consisting of an amine, an amide, a hydroxyl, or a thiol group; and (c) 0.1 to 5.0 wt. percent of a methylol containing aminoplast resin which cross-links with said polymer thereby forming a gel of a size and strength sufficient to close pores in one or more permeable zones of said formation, said resin having amine and aldehyde in a critical mole ratio of from about 1:6 to about 1:30 respectively, which ratios are sufficient to form substantially improved stable gels for utilization in a subterranean formation during the recovery of hydrocarbonaceous fluids.

Claim 12

The process as recited in claim 9 wherein said resin is a member selected from the group consisting of melamine-formaldehyde, urea formaldehyde, ethylene urea formaldehyde, propylene urea formaldehyde, and triazone, uron, and glyoxal amino resins.

Claim 13

The process as recited in claim 9 wherein said polymer is a member selected from the group consisting of polyacrylamid, polyvinyl alcohol, xanthan biopolymers, Kelco S-130 biopolymers, poly (acrylamideco-acrylamido-2-methyl-propanesulfonate), Phillips HE polymers, and acrylamide modified polyvinyl alcohol.

Claim 14

The process as recited in claim 9 wherein said gel is formed under salinity concentrations encountered in an oil reservoir.

Claim 15

The process as recited in claim 9 wherein said gel is of a stability sufficient to withstand high temperatures encountered in an oil reservoir for periods greater than three months.

Claim 16

The process as recited in claim 9 wherein said resin can condense to form a cured resin.

Claim 17

The process as recited in claim 9 wherein a gelation reaction which produces said gel proceeds under substantially all pH conditions.

Claim 18

The process as recited in claim 9 wherein said gel is unaffected by carbonate, bicarbonate, and sulfate anions encountered in an oil reservoir.