Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for realizing CO2 miscible-phase oil displacement through underground multi-stage contact separation

A contact separation, CO2 technology, applied in wellbore/well components, earthwork drilling, production of fluids, etc., can solve problems such as being unsuitable for large-scale popularization and application, volatile injection materials, and large injection volume, etc., to reduce output The effect of reducing fluid difficulty, reducing injection volume, and reducing corrosion

Pending Publication Date: 2022-05-13
CHINA PETROLEUM & CHEM CORP +1
View PDF2 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method has a large amount of injection, the injection is volatile, and the construction is dangerous. Due to economic and safety considerations, this method is not suitable for large-scale application

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
  • Method for realizing CO2 miscible-phase oil displacement through underground multi-stage contact separation
  • Method for realizing CO2 miscible-phase oil displacement through underground multi-stage contact separation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] Such as figure 1 As shown, the present invention provides a downhole multi-stage contact separation to realize CO 2 Miscible drive method. First, supercritical CO with a certain pressure and flow rate 2 The gas is injected from the wellhead casing gate 3 of the injection well 1, migrates downward through the first oil casing annulus 4, and is blocked by the first packer 8, injects into the upper production layer 7, migrates in the formation, and continuously React with crude oil to carry out CO 2 Immiscible flooding, the production well 2 is in normal production, and under the action of the second packer 12 and the third packer 15, the production fluid enters the second CO2 from the second oil casing annulus 14 2 Crude oil separation device 13 (unopened), and upward output from the production well tubing, real-time monitoring and analysis of the production fluid situation, when production well 2 production fluid found CO 2 After that, turn on the second downhole CO ...

Embodiment 2

[0039] Such as figure 2 As shown, the present invention provides downhole multi-stage contact separation to realize CO 2 Schematic diagram of the mixing principle. First to CO 2 , crude oil C 2-6 Components and Crude C 7 Make a three-component phase diagram of the above components. CO 2 The gas is injected into the upper production layer 7 from the injection well 1, contacts with the formation crude oil F, and mixes into the production well 2, and the mixed components pass through the second downhole CO 2 The crude oil separation device 13 is separated into two phases G1 and L1. The L1 component is migrated upward from the tubing to be produced, and the G1 component is migrated downward from the tubing, and is injected into the lower production layer 11 through the booster pump 16, and is mixed with the crude oil F. Secondary contact displacement, the displacement fluid enters the tubing of the injection well 1 and passes through the first downhole CO 2 The crude oil s...

Embodiment 3

[0041] Utilize concrete method of the present invention as follows:

[0042] (1) Select oil reservoir and layout wells. Comprehensively analyze the existing geological and reservoir knowledge, and clarify the scale of recoverable reserves of remaining oil, the connection relationship between oil layers and wellbore, and the composition and properties of crude oil. The selected oil reservoir has a burial depth greater than 1000m, at least two or more oil layers, and the interval between oil layers is greater than 50 meters.

[0043] Predict productivity and economic evaluation through reservoir numerical simulation, and determine well layout method. At least one injection and one production, or one injection and multiple production wells and multiple injection and multiple production wells, the well spacing is 100-150 meters.

[0044] (2) Supporting production strings. According to the design requirements, the downhole CO 2 Crude oil separation device, pressure control devi...

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

No PUM Login to View More

Abstract

The invention belongs to the technical field of oil-gas field development. The invention discloses a method for realizing CO2 miscible-phase oil displacement through underground multi-stage contact separation, which comprises the following steps of: injecting CO2 into an injection well to be in contact with crude oil in formation displacement to extract and gradually enrich light hydrocarbon components, and enabling CO2 displacement fluid to enter a CO2 crude oil separation device of a production well to be subjected to depressurization separation; the CO2 displacement fluid enriched with the light hydrocarbon components continues to be injected into the stratum to achieve multiple times of contact extraction with the crude oil, the CO2 displacement fluid is rich in the light hydrocarbon components after multiple times of circulation in the stratum to achieve the miscible phase condition with the crude oil in the stratum, and therefore CO2 miscible phase displacement is achieved. On the basis that no chemical agent is injected, light hydrocarbon components are extracted and enriched from the oil reservoir through CO2, CO2 oil reservoir internal circulation multi-stage contact miscible-phase displacement is achieved, the oil reservoir recovery rate can be greatly increased, and the oil reservoir application range of CO2 miscible-phase displacement is greatly expanded.

Description

technical field [0001] The invention relates to the technical field of oil and gas field development, and more specifically relates to a downhole multi-stage contact separation to realize CO 2 Miscible flooding method. Background technique [0002] CO 2 Oil flooding can not only alleviate the greenhouse effect but also significantly increase the oil recovery rate. It has wide application range, high oil flooding efficiency and low cost, and has attracted more and more attention at home and abroad. The United States, Canada, etc. have entered a large number of mine field tests or application stages, and achieved good results. Among various EOR methods, CO 2 Oil flooding is considered one of the most promising EOR methods. [0003] However, due to differences in sedimentary environments, formation conditions and crude oil properties at home and abroad, CO 2 The application effect of oil flooding in China is quite different from expectations. my country's oil reservoirs h...

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): E21B43/16
CPCE21B43/164
Inventor 冯海顺张绍东王涛刘廷峰王善堂戴宇婷蔡文斌白艳丽林吉生尚跃强
Owner CHINA PETROLEUM & CHEM CORP