Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Chemical flooding method of medium-permeability oil reservoir

A chemical flooding and oil seepage technology, which is applied in chemical instruments and methods, earth drilling, and drilling compositions, etc., can solve the problems of easy channeling and ineffective displacement of chemical oil flooding agents, and achieve improved flooding Oil effect, enhanced oil recovery, enhanced injectivity effect

Pending Publication Date: 2020-09-11
CHINA PETROLEUM & CHEM CORP +1
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in the actual chemical flooding application process, the chemical oil displacement agent is easy to channel, and the chemical oil displacement agent has a certain period of action, which cannot effectively displace the remaining oil in the middle and low permeability cores, and achieve the purpose of enhancing oil recovery.

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] The reservoirs in the chemical flooding method of medium permeability reservoirs in Examples 1-5 and Comparative Examples are artificial cores, and the artificial cores are three times the permeability difference of φ2.5cm×10cm (300×10cm -3 μm 2 / 900×10 -3 μm 2) artificial double-tube parallel heterogeneous cylindrical core with a porosity of 24%. Before chemical flooding, the cores were treated as follows: Saturation of the cores with crude oil at 65°C (crude oil after dehydration and degassing treatment in an oilfield reservoir, 12.8mPa·s), and the original oil saturation (Soi) was controlled as About 70%. Before starting the chemical flooding of Examples 1 to 5 and the comparative examples, inject the filtered aged sewage (the aged sewage used in Example 1) into the artificial core saturated with crude oil at a rate of 50mL / h to drive oil respectively. , the water flooding ends after no more oil is produced, and the water flooding recovery is calculated, and the ...

Embodiment 2

[0044] The chemical flooding method of the middle permeability oil reservoir of the present embodiment comprises the following steps:

[0045] 1) Inject the heterogeneous dispersion system into the artificial core at a flow rate of 50mL / h to form a pre-slug of 0.05PV;

[0046] 2) Then inject polyacrylamide aqueous solution into the artificial core to form the first main body slug of 0.25PV, inject the heterogeneous dispersion system to form the profile control slug of 0.05PV, inject polyacrylamide aqueous solution to form the second main body of 0.3PV Slug;

[0047] 3) Inject the heterogeneous dispersion system into the artificial core to form a protective slug of 0.05PV;

[0048] 4) Finally, inject aged sewage into the artificial core at a flow rate of 50mL / h for oil displacement, and the subsequent water flooding ends after no more oil is produced.

[0049] The mass fraction of polyacrylamide in the heterogeneous dispersion system in step 1), 2) and 3) of this embodiment i...

Embodiment 3

[0051] The chemical flooding method of the middle permeability oil reservoir of the present embodiment comprises the following steps:

[0052] 1) Inject the heterogeneous dispersion system into the artificial core at a flow rate of 50mL / h to form a pre-slug of 0.05PV;

[0053] 2) Then inject polyacrylamide aqueous solution into the artificial core to form the first main body slug of 0.2PV, inject heterogeneous dispersion system to form the first profile control slug of 0.025PV, and inject polyacrylamide aqueous solution to form the second slug of 0.2PV. Two main body slugs, a second profile control slug of 0.025PV formed by injecting a heterogeneous dispersion system, and a third main body slug of 0.15PV formed by injecting polyacrylamide aqueous solution;

[0054] 3) Inject the heterogeneous dispersion system into the artificial core to form a protective slug of 0.05PV;

[0055] 4) Finally, inject aged sewage into the artificial core at a flow rate of 50mL / h for oil displace...

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
Viscosityaaaaaaaaaa
Viscosityaaaaaaaaaa
Elastic modulusaaaaaaaaaa
Login to View More

Abstract

The invention relates to a chemical flooding method of a medium-permeability oil reservoir, and belongs to the technical field of petroleum chemical flooding development. The chemical flooding methodincludes the following steps that 1), a first heterogeneous dispersion system is injected into a reservoir stratum, and a front slug is formed; 2), then a polymer water solution is injected into the reservoir stratum, a main plug is formed, or a polymer water solution and a profile control system are alternately injected into the reservoir stratum, and the main slug and a profile control slug areformed correspondingly; and 3), a second heterogeneous dispersion system is injected into the reservoir stratum, and a protective slug is formed. The first heterogeneous dispersion system is mainly composed of a first polymer, a viscoelastic particle oil displacement agent and water. The polymer water solution is mainly composed of a second polymer and water. The second heterogeneous dispersion system is mainly composed of a third polymer, a viscoelastic particle oil displacement agent and water. By means of the chemical flooding method, the rock core stemming ratio of the medium-permeabilityoil reservoir can be increased, remaining oil in a strong flooding region and a medium-permeability rock core is effectively started, and the effect of greatly increasing the raw oil recovery rate isachieved.

Description

technical field [0001] The invention relates to a chemical flooding method for medium-permeability oil reservoirs, and belongs to the technical field of petrochemical flooding development. Background technique [0002] At present, China's oil energy demand continues to grow, but most of the domestic onshore oilfields' Class I and II scale reserves have been used up, and the oilfields have entered the late stage of development, and the remaining reserves of medium-permeable oil reservoirs have become the main position for oilfields to maintain production. [0003] The permeability of medium-permeability reservoirs has a large range of variation, generally 50-1000×10 -3 μm 2 . The remaining oil in medium permeability reservoirs is distributed in the strongly water flooded area, accounting for 50-60% of the remaining oil reserves. A considerable proportion of the remaining oil is mainly distributed in the oil layers below the average permeability, which is the focus of chemic...

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
IPC IPC(8): E21B33/13E21B43/22C09K8/588
CPCC09K8/588E21B33/13E21B43/16
Inventor 张卓卢军王正欣李岩唐金星薛国勤李洪生朱义清束华东
Owner CHINA PETROLEUM & CHEM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com