Injection water viscosifier for enhanced oil recovery
AssigneeThe Goodyear Tire & Rubber Company
InventorKenneth F. Castner
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Abstract
High molecular weight N,N-dimethylacrylamide copolymers and terpolymers were synthesized. These polymers offer outstanding advantages as injection water viscosifiers in enhanced oil recovery processes including chemical, miscible, and steam or in processes requiring profile improvement through adsorption and/or gelation. They are very valuable in applications where high salinity is a problem since they are relatively insensitive to metal salts (such as those containing polyvalent ions, such as Ca.sup.++ and Mg.sup.++.).
Claims27
A high molecular weight water soluble polymer comprised of chain linkages derived from N,N-dimethylacrylamide and at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate having a molecular weight above about 1,000,000, wherein said water soluble polymer has at least 30 weight percent of its chain linkages being derived from N-N-dimethylacrylamide and from 0.1 to 5 weight percent of its chain linkages being derived from at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate.
A process for the synthesis of a high molecular weight water soluble polymer by an aqueous polymerization which comprises initiating said polymerization with a metal persulfate and at least one member selected from the group consisting of sodium metabisulfite, sodium thiosulfate, and sodium dithionite;
- wherein said polymerization is conducted in an aqueous reaction mixture which is comprised of (a) water, (b) N,N-dimethylacrylamide, (c) at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate, (d) said metal persulfate, and (e) said members selected from the group consisting of sodium metabisulfite, sodium thiosulfate, and sodium dithionite;
- and wherein the high molecular weight water soluble polymer produced has at least 30 weight percent of its chain linkages being derived from N,N-dimethylacrylamide and from 0.1 to 5 weight percent of its chain linkages being derived from at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate.
An aqueous polymer solution comprising:
- water and a high molecular weight water soluble polymer comprised of chain linkages derived from N,N-dimethylacrylamide and at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate having a molecular weight above about 1,000,000, wherein said water soluble polymer has at least 30 weight percent of its chain linkages being derived from N,N-dimethylacrylamide and from 0.1 to 5 weight percent of its chain linkages being derived from at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate.
An aqueous polymer solution as specified in claim wherein a sufficient amount of said water soluble polymer is dissolved in said water to increase the Brookfield viscosity of said aqueous polymer solution to between 2 cps and 30 cps.
A high molecular weight water soluble polymer comprised of chain linkages derived from N,N-dimethylacrylamide;
- at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate;
- and at least one member selected from the group consisting of sodium 2-acrylamido-2-methylpropanesulfonate, potassium 2-acrylamido-2-methylpropanesulfonate, ammonium 2-acrylamido-2-methylpropanesulfonate, and calcium 2-acrylamido-2-methylpropanesulfonate;
- wherein said water soluble polymer has from about 30 to 95 weight percent of its chain linkages being derived from N,N-dimethylacrylamide:
- wherein said water soluble polymer has from about 4 to 50 weight percent of its chain linkages being derived from at least one member selected from the group consisting of sodium 2-acrylamido-2-methylpropanesulfonate, potassium 2-acrylamido-2-methylpropanesulfonate, ammonium 2-acrylamido-2-methylpropanesulfonate, and calcium 2-acrylamido-2-methylpropanesulfonate;
- wherein said water-soluble polymer has from at least about 0.1 weight per cent of its chain linkages being derived from at least one member selected from the group consisting of N-methylol acrylamide and sodium styrene sulfonate and wherein said water soluble polymer has a molecular weight of about about 1,000,000.
A high molecular weight water soluble polymer comprised of chain linkages derived from a major amount of N,N-dimethylacrylamide and from 0.1 to 5 weight percent of at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate having a molecular weight above about 1,000,000.
An aqueous polymer solution comprising:
- water and a high molecular weight water soluble polymer comprised of chain linkages derived from a major amount of N,N-dimethylacrylamide and from 0.1 to 5 weight percent of at least one member selected from the group consisting of N-methylolacryolamide and sodium styrene sulfonate having a molecular weight above about 1,000,000.
A high molecular weight water soluble polymer comprised of chain linkages derived from a major amount of N,N-dimethylacrylamide;
- at least one member selected from the group consisting of N-methylolacrylamide and sodium styrene sulfonate;
- and at least one member selected from the group consisting of sodium 2-acrylamido-2-methylpropanesulfonate, potassium 2-acrylamido-2-methylpropanesulfonate, ammonium 2-acrylamido-2-methylpropanesulfonate, and calcium 2-acrylamido-2-methylpropanesulfonate;
- wherein said water soluble polymer has from about 4 to 50 weight percent of its chain linkages being derived from at least one member selected from the group consisting of sodium 2-acrylamido-2-methylpropanesulfonate, potassium 2-acrylamido-2-methylpropanesulfonate, ammonium 2-acrylamido-2-methylpropanesulfonate, and calcium 2-acrylamido-2-methylpropanesulfonate;
- and calcium 2-acrylamido-2-methylpropanesulfonate;
- wherein said water-soluble polymer has from at least about 0.1 weight per cent of its chain linkages being derived from at least one member selected from the group consisting of N-methylol acrylamide and sodium styrene sulfonate and wherein said water soluble polymer has a molecular weight of above about 1,000,000.
Dependencies are inferred from the claim text.