Chevron U.s.a. Inc.

Robert Matthew Dean

Varadarajan Dwarakanath

Sophany Thach

Taimur Malik

Dennis Arun Alexis

Do Hoon Kim

Dustin Luke Walker

Sumitra Subrahmanyan

Anette Poulsen

Will S Slaughter

Aspects of the invention relate to compositions and methods that are used for the remediation of near-wellbore damage in regions of formations near injection wells in communication with subterranean reservoirs. The damage is caused by previous injection of a polymer emulsion into the injection well. A specific aspect is a method of injecting into the subterranean reservoir a composition containing an olefin sulfonate, a sulfosuccinate, and a chemical selected from an alcohol alkoxylated sulfate, an alcohol alkoxylated carboxylate, or a combination thereof. The polymer emulsion is thereby dissolved, cleaned and/or flushed away from the region near the injection well.

Method for remediation of damage in regions of formations near injection wells

Systems and methods for automated fluid sampling for tracer testing are described. In one aspect, an automated fluid sampling system includes a pressurized line, such as a production well or an injection well connectively and a fluid separation vessel receiving sample fluids therefrom. The fluid separation vessel includes a plunger and is configured for gravity-mediated phase separation of the sample fluids into a plurality of aqueous, organic and/or gas phase fluid fractions and includes pluralities of inlet and outlet ports for mediating flow of sample fluids therethrough. At least one purging fluid source, such as a gas or liquid, is used for driving the plunger. Sample fluid collection vessels receive phase-separated sample fluids from the fluid separation vessel. Pluralities of fluid lines and solenoid valves operatively link the pressurized line, purging fluid sources, sample fluid collection vessels, and disposal vessel to one another, whereby a controller selectively manages the automated flow of fluids through the various fluid lines.

Automated fluid fraction sampling system

Embodiments of a polymer composition are disclosed for use in enhancing the production of oil from a formation. In one embodiment, the composition includes 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 the group of surfactants, glycol ethers, alcohols, co-solvents, and mixtures thereof, at a weight ratio of powder polymer to water soluble solvent ranging from 20:80 to 80:20. The polymer composition is substantially anhydrous. The polymer composition is hydrated in an aqueous fluid for an injection solution in less than or equal to 4 hours containing a polymer concentration ranging from 100 ppm to 50,000 ppm and having a filter ratio of less than or equal to 1.5 at 15 psi using a 1.2 &#x3bc;m filter.

Polymer compositions

A method for making a polymer suspension for use in enhancing the production of oil from a formation is disclosed. In one embodiment, the method comprises mixing a powder polymer having an average molecular weight of 0.5 to 30 Million Daltons into a water soluble solvent having an HLB of greater than or equal to 8 for less than or equal to 24 hours. The water soluble solvent is selected from a group, at a weight ratio from 20:80 to 80:20. The polymer suspension is stable, pumpable, and substantially anhydrous; and it is hydrated for an injection solution in less than or equal to 4 hours, containing a polymer concentration ranging from 100 ppm to 50,000 ppm and having a filter ratio of less than or equal to 1.5 at 15 psi using a 1.2 &#x3bc;m filter, by mixing a sufficient amount of the polymer suspension in an aqueous fluid.

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 &#x3bc;m 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.

A method of enhancing oil recovery in a subterranean reservoir is disclosed. In one embodiment, the method comprises providing a wellbore and a polymer suspension. 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 of 20:80 to 80:20. The method comprises providing an aqueous fluid, mixing a sufficient amount of the polymer suspension in the aqueous fluid for the polymer to be hydrated resulting an injection solution in less than or equal to 4 hours, and injecting the injection solution into the wellbore. The injection solution contains a polymer concentration ranging from 100 ppm to 50,000 ppm and has a filter ratio of less than 1.5 at 15 psi using a 1.2 &#x3bc;m filter.

The present disclosure provides techniques for inline injection of water and chemicals for a dump flood. The techniques include collecting water from a source reservoir into a water collection zone of an adjacent water injection well, and injecting a chemical solution into the water injection well. The water and the chemical solution are then mixed downhole in a mixer, such as a static mixer. The mixed injection fluid is then directly injected into an adjacent target reservoir.

Systems and methods for inline chemical injection for dump flood water injectors

Aspects of the invention relate to compositions and methods that are used for remediation of near-wellbore damage. A specific aspect is a composition comprising an olefin sulfonate, a sulfosuccinate, and a chemical selected from the group consisting of an alcohol alkoxylated sulfate, an alcohol alkoxylated carboxylate, or a combination thereof.

Growing community of inventors

Houston, TX, United States of America

Robert Matthew Dean