Pre-crosslinked gel granulate for profile control and polymer flooding as well as preparation method and application of pre-crosslinked gel granulates

A technology of gel particles and pre-crosslinking, which is applied in the direction of chemical instruments and methods, drilling compositions, etc., can solve the problems of difficulty in on-site implementation, large loss of effective viscosity, and shear thinning, etc., to improve oil recovery Yield, avoiding shear thinning, and controlling the effect of operating cycle

Active Publication Date: 2012-07-18
PETROCHINA CO LTD
View PDF3 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In recent years, although tertiary oil recovery measures such as polymer flooding have achieved better results, there are still problems such as high cost of oil displacement and difficulty in field implementation; ” in the reservoirs, there are still serious problems of channeling and accumulation in some wells, which affects the effect of polymer injection, and due to the limitations of the polymer itself, the effective viscosity loss in high-temperature and high-salinity formations is very large, often Can't achieve the expected purpose
ASP flooding technology has gradually been widely used in Daqing and other old oilfields. The use of surfactants to reduce interfacial tension greatly reduces capillary force, and oil and water achieve miscible flow, thus starting the low permeability reservoir. Residual oil, but ASP flooding technology and polymer flooding have similar problems: shear thinning, affected by reservoir conditions, and both polymer flooding and ASP flooding will pollute oil-bearing low-permeability layers, making subsequent water flooding unable to achieve best results
Flexible particles can form dynamic plugging in the deep part of the reservoir, but for fractures and ultra-high permeability layers caused by high-intensity water erosion near the well, high-strength plugging agents must be used for anti-channeling operations, otherwise the flexible diverting agent can improve recovery The effect of the rate cannot be brought into full play
[0007] To sum up, so far, in the water plugging and profile control technology of oil production, the profile control and the adjustment of the oil-water mobility ratio cannot be carried out simultaneously, and no prior art reports have solved this problem.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Pre-crosslinked gel granulate for profile control and polymer flooding as well as preparation method and application of pre-crosslinked gel granulates
  • Pre-crosslinked gel granulate for profile control and polymer flooding as well as preparation method and application of pre-crosslinked gel granulates
  • Pre-crosslinked gel granulate for profile control and polymer flooding as well as preparation method and application of pre-crosslinked gel granulates

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] formula

[0041]

[0042]

[0043] The mass percent concentration of the monomer (AA+AM) is 30g / 142.66=21%. The ratio of unstable crosslinking agent to complex monomer is 1:200.

[0044] Polymerization process

[0045] Add acrylamide, acrylic acid and polyethylene glycol dimethacrylate into 110 g of water to fully dissolve. Add NaCO after dissolving 3 Neutralize the solution. Then add TMEDA, urea, ammonia and sodium hydroxide. The solution was purged with nitrogen gas for 30 min, and then K was added to the solution 2 S 2 o 8 , The obtained solution was purged with nitrogen again for 10 minutes, and then placed in a 10°C incubator. First vacuumize to -10KPa for 30 minutes to remove the oxygen in the air, then maintain the vacuum state and inject pure nitrogen at the same time to remove the oxygen in the solution, start the polymerization process, completely gel after 12 hours, and get the bulk gel.

[0046] After forming the gel, put the bulk gel in disti...

Embodiment 2

[0053] formula

[0054]

[0055] The mass percent concentration of the monomer (AA+AM) is 15g / 127.4675=11.76%

[0056] The ratio of unstable crosslinking agent to composite monomer is 1:400

[0057] Polymerization process

[0058] Add acrylamide, acrylic acid and polyethylene glycol dimethacrylate to fully dissolve in water. Add NaCO after dissolving 3 Neutralize the solution. Then add TMEDA, urea, ammonia and sodium hydroxide. The solution was purged with nitrogen gas for 30 min, and then K was added to the solution 2 S 2 o 8, The obtained solution was purged with nitrogen again for 10 minutes, and then placed in a 10°C incubator. First vacuumize to -10KPa for 30 minutes to remove the oxygen in the air, then maintain the vacuum state while injecting pure nitrogen to remove the oxygen in the solution, and start the polymerization process. After 13 hours, the gel is completely formed and the bulk gel is obtained.

[0059] After forming the gel, put the bulk gel in d...

Embodiment 3

[0064] formula

[0065]

[0066] The mass percent concentration of the monomer (AA+AM+AMPS) is 30 / 136.54=22.0%

[0067] The ratio of unstable crosslinking agent to complex monomer is 1:1000

[0068] Polymerization process

[0069] With embodiment 1.

[0070] Hydrolysis test

[0071] The hydrolysis experimental procedure is the same as in Example 1.

[0072] At 80°C, it takes 6 days for the pre-crosslinked gel particles to be hydrolyzed into a polymer solution, and the viscosity of the polymer solution obtained after hydrolysis is 100cp; at 60°C, it takes about 35 days for complete hydrolysis, and the viscosity of the obtained polymer solution is 160cp. The viscosity of the resulting polymer solution was 190 cp for hydrolysis after 150 days at 45°C.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
particle size (mesh)aaaaaaaaaa
Login to view more

Abstract

The invention provides a pre-crosslinked gel granulate for profile control and polymer flooding as well as a preparation method and application of a pre-crosslinked gel granulate. The pre-crosslinked gel granulate belongs to a reagent for oil exploitation, and is obtained by polymerizing and crosslinking a composite monomer and an instable crosslinking agent under initiation of an initiator so as to obtain body gel, drying and grinding, wherein the composite monomer comprises acrylamide and acrylic acid; and the instable crosslinking agent is selected from polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol diacrylate, glycol diacrylate, trimethylolpropane triacrylate, ethoxy trihydroxymethyl triacrylate and the like. The volume of the gel granulate is expanded by absorbing water; after the gel granulates are injected into an oil deposit, big pore canals and ultrahigh pervious layers are plugged in the immediate vicinity of wellbore of an oil layer, so that the injected water enters into a low pervious layer area to start residual oil; after acting for certain time, the gel granulate is automatically hydrolyzed into a solution, so that oil-water mobility control is realized; and the gel granulate has double functions of profile control and polymer flooding, is suitable for the oil deposits of a high water holding period, and can be used for improving the recovery rate of petroleum.

Description

technical field [0001] The invention relates to a gel particle for profile control and flooding in oil exploitation, specifically a pre-crosslinked gel particle with dual functions of profile control and polymer flooding, its preparation method and application. Background technique [0002] With the continuous development of the oil field, the heterogeneity of the reservoir is becoming more and more serious. A large amount of injected water scours, the clay and cement in the oil layer expand and dissolve, the migration of particles, and the sand production become heavier, which further deteriorates the geological heterogeneity. During the development process, the following problems often appear, such as: prominent plane contradictions, plane injection water rushes along the high permeability zone to form waterways; prominent interlayer contradictions, uneven production and suction profiles, and single-layer rushing phenomenon in the vertical direction; high viscosity of under...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08F220/56C08F220/06C08F220/58C08F222/02C08F220/34C08F226/02C09K8/588C09K8/42
Inventor 贾旭唐孝芬王家禄刘玉章白宝君唐廷基杨立民
Owner PETROCHINA CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap