Polymer compositions

Patent metadata

Field	Value
Publication number	US-9902895-B2
Application number	US-201514927091-A
Country	US
Kind code	B2
Filing date	Oct 29, 2015
Priority date	Oct 31, 2014
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

An injection solution for injecting into a subterranean reservoir to enhance production and recovery of oil from the reservoir is disclosed. In one embodiment, the injection solution is prepared by mixing a sufficient amount of a pumpable, stable and substantially anhydrous polymer suspension in an aqueous fluid for the polymer to be hydrated in less than or equal to 4 hours, resulting in the injection solution containing a polymer concentration ranging from 100 ppm to 50,000 ppm. The injection solution has a filter ratio of less than or equal to 1.5 at 15 psi using a 1.2 μm filter. The polymer suspension comprises a powder polymer having an average molecular weight of 0.5 to 30 Million Daltons suspended in a water soluble solvent having an HLB of greater than or equal to 8 and selected from a group, at a weight ratio from 20:80 to 80:20.

First claim

The invention claimed is:

1. An injection solution for injecting into a subterranean reservoir to enhance production and recovery of oil from the reservoir, the injection solution is prepared by mixing a sufficient amount of a pumpable and stable polymer suspension containing less than or equal to 3 wt. % water in an aqueous fluid for the polymer to be hydrated in less than or equal to 4 hours, resulting in the injection solution containing a polymer concentration ranging from 100 ppm to 50,000 ppm; the injection solution has a filter ratio of less than or equal to 1.5 at 15 psi using a 1.2 μm filter;
wherein the polymer suspension comprises a powder polymer having an average molecular weight of 0.5 to 30 Million Daltons suspended in a water soluble solvent at a weight ratio of powder polymer to water soluble solvent ranging from 20:80 to 80:20, wherein the water soluble solvent has a HLB of greater than or equal to 8 and comprises a mixture of non-ionic and anionic surfactants;
wherein the aqueous fluid selected from any of surface water, water recovered from a production well, sea water, synthetic water, produced reservoir brine, reservoir brine, fresh water, produced water, water, saltwater, brine, synthetic brine, synthetic seawater brine, and mixtures thereof.

2. The injection solution of claim 1 , wherein the powder polymer is a biopolymer that is a polysaccharide.

3. The injection solution of claim 1 , wherein the powder polymer is a biopolymer or a synthetic polymer.

4. The injection solution of claim 1 , wherein the powder polymer is a synthetic polymer selected from the group of polyacrylamides, partially hydrolyzed polyacrylamides, hydrophobically-modified associative polymers, copolymers of polyacrylamide and one or both of 2-acrylamido 2-methylpropane sulfonic acid and salts thereof and N-vinyl pyrrolidone, single-, co-, or ter-polymers of N-vinyl pyrrolidones, polyacrylic acid, polyvinyl alcohol, and mixtures thereof.

5. The injection solution of claim 1 , wherein the water soluble solvent further comprises isopropyl alcohol (IPA), n-propyl alcohol, isobutyl alcohol (IBA), methyl-isobutyl alcohol, secondary butyl alcohol (SBA), ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, and mixtures thereof.

6. The injection solution of claim 1 , wherein the water soluble solvent is selected from ethoxylated surfactants, nonylphenol ethoxylates, alcohol ethoxylates, internal olefin sulfonates, isomerized olefin sulfonates, alkyl aryl sulfonates, medium alcohol (C10 to C17) alkoxy sulfates, alcohol ether [alkoxy]carboxylates, alcohol ether [alkoxy]sulfates, alkyl sulfonate, a-olefin sulfonates (AOS), dihexyl sulfosuccinates, alkylpolyalkoxy sulfates, sulfonated amphoteric surfactants, and mixtures thereof.

7. The injection solution of claim 1 , wherein the water soluble solvent further comprises a co-solvent, wherein the co-solvent is selected from the group of an ionic surfactant, non-ionic surfactant, anionic surfactant, cationic surfactant, nonionic surfactant, amphoteric surfactant, ketones, esters, ethers, glycol ethers, glycol ether esters, lactams, cyclic ureas, alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, alicyclic hydrocarbons, nitroalkanes, unsaturated hydrocarbons, halocarbons, alkyl aryl sulfonates (AAS), a-olefin sulfonates (AOS), internal olefin sulfonates (IOS), alcohol ether sulfates derived from propoxylated Ci 2 -C 2 o alcohols, ethoxylated alcohols, mixtures of an alcohol and an ethoxylated alcohol, mixtures of anionic and cationic surfactants, disulfonated surfactants, aromatic ether polysulfonates, isomerized olefin sulfonates, alkyl aryl sulfonates, medium alcohol (C10 to C17) alkoxy sulfates, alcohol ether [alkoxy]carboxylates, alcohol ether [alkoxy]sulfates, primary amines, secondary amines, tertiary amines, quaternary ammonium cations, cationic surfactants that are linked to a terminal sulfonate or carboxylate group, alkyl aryl alkoxy alcohols, alkyl alkoxy alcohols, alkyl alkoxylated esters, alkyl polyglycosides, alkoxy ethoxyethanol compounds, isobutoxy ethoxyethanol (“iBDGE”), n-pentoxy ethoxyethanol (“n-PDGE”), 2-methylbutoxy ethoxyethanol (“2-MBDGE”), methylbutoxy ethoxyethanol (“3-MBDGE”), (3,3-dimethylbutoxy ethoxyethanol (“3,3-DMBDGE”), cyclohexylmethyleneoxy ethoxyethanol (hereafter “CHMDGE”), 4-Methylpent-2-oxy ethoxyethanol (“MIBCDGE”), n-hexoxy ethoxyethanol (hereafter “n-HDGE”), 4-methylpentoxy ethoxyethanol (“4-MPDGE”), butoxy ethanol, propoxy ethanol, hexoxy ethanol, isoproproxy 2-propanol, butoxy 2-propanol, propoxy 2-propanol, tertiary butoxy 2-propanol, ethoxy ethanol, butoxy ethoxy ethanol, propoxy ethoxy ethanol, hexoxy ethoxy ethanol, methoxy ethanol, methoxy 2-propanol and ethoxy ethanol, n-methyl-2-pyrrolidone, dimethyl ethylene urea, and mixtures thereof.

8. The injection solution of claim 1 , wherein the anionic surfactant is present in an amount of less than or equal to 5 wt. % as a stabilizer.

9. The injection solution of claim 1 , wherein the polymer suspension comprises a powder polymer suspended in a water soluble solvent at a weight ratio of powder polymer to water soluble solvent ranging from 30:70 to 70:30.

10. The injection solution of claim 9 , wherein the polymer suspension comprises a powder polymer suspended in a water soluble solvent at a weight ratio of powder polymer to water soluble solvent ranging from 40:60 to 60:40.

11. The injection solution of claim 1 , wherein the injection solution is prepared by mixing the pumpable and stable polymer suspension containing less than or equal to 3 wt. % water in an aqueous fluid in less than or equal to 2 hours.

12. The injection solution of claim 11 , wherein the injection solution is prepared by mixing the pumpable and stable polymer suspension containing less than or equal to 3 wt. % water in an aqueous fluid in less than or equal to 1 hour.

13. The injection solution of claim 1 , wherein the injection solution is prepared by mixing the pumpable and stable polymer suspension containing less than or equal to 3 wt. % water in a mixing tank or via an in-line static mixer.

14. The injection solution of claim 1 , wherein the injection solution has a filter ratio of less than or equal to 1.2 at 15 psi using a 1.2 μm filter.

15. The injection solution of claim 1 , wherein the injection solution has a turbidity of less than or equal to 20 NTU.

16. The injection solution of claim 15 , wherein the injection solution has a turbidity of less than or equal to 15 NTU.

17. The injection solution of claim 16 , wherein the injection solution has a turbidity of less than or equal to 10 NTU.

18. The injection solution of claim 1 , wherein after the powder polymer is suspended in the water soluble solvent for a period of at least 2 hours with a turbidity decrease of at least 25%.

19. The injection solution of claim 18 , wherein after the powder polymer is suspended in the water soluble solvent for a period of at least 2 hours with a turbidity decrease of at least 50%.

20. The injection solution of claim 19 , wherein after the powder polymer is suspended in the water soluble solvent for a period of at least 2 hours with a turbidity decrease of at least 75%.

21. The injection solution of claim 1 , wherein the polymer in the injection solution has an average particle size ranging from 0.01 to 10 μm.

22. The injection solution of claim 1 , wherein the water soluable solvent further comprises a glycol ether, an alcohol, a co-solvent, and mixtures

Assignees

• Chevron Usa Inc

Inventors

• Dwarakanath Varadarajan
• Dean Robert M
• Kim Do Hoon
• Alexis Dennis Arun
• Thach Sophany
• Malik Taimur
• Poulsen Anette
• Subrahmanyan Sumitra

Classifications

• C09K8/588 Primary

  characterised by the use of specific polymers {(polymeric surfactants C09K8/584)} · CPC title

• C09K8/88

  macromolecular compounds · CPC title

• C09K8/68

  containing organic compounds · CPC title

• E21B43/26

  by forming crevices or fractures · CPC title

• C09K8/584

  characterised by the use of specific surfactants · CPC title