Supercritical carbon dioxide based fracturing liquid system and application thereof

A carbon dioxide and supercritical technology, applied in production fluid, drilling composition, bulk chemical production, etc., can solve the problem that the water-based fracturing fluid system is no longer applicable, reduce the permeability of the proppant packing layer, fracturing fluid Incomplete gel breaking and other problems, to achieve good sand-carrying performance, facilitate crude oil extraction, and improve formation permeability

Active Publication Date: 2014-01-29
CHINA NAT PETROLEUM CORP CHUANQING DRILLING ENG CO LTD +1
View PDF5 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, these fracturing fluid systems have disadvantages, such as the incomplete gel breaking of the fracturing fluid, and the residue will remain in the fracture after the gel is broken, and the polymer remaining in the fracture will seriously reduce the permeability of the proppant packing layer, thus damaging the production layer, leading to poor fracturing effect
[0003] In addition, for water-sensitive and water-locked formations, the traditional water-based fracturing fluid system is no longer applicable

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
  • Supercritical carbon dioxide based fracturing liquid system and application thereof
  • Supercritical carbon dioxide based fracturing liquid system and application thereof
  • Supercritical carbon dioxide based fracturing liquid system and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] The carbon dioxide is heated to 62°C in the chamber, and the pressure rises to 20MPa. Take 5% viscosity increasing agent and 6.5% conditioning agent and add it to 88.5% carbon dioxide through closed injection equipment, stir and dissolve to prepare a supercritical carbon dioxide fracturing fluid system. The system has been tested for temperature resistance and shear resistance, and the viscosity fluctuates within 9-12mPa·s, see the attached figure 1 .

[0035] The above percentages are all percentages by mass. Described viscosity raising agent is higher fatty acid fat, and it is formed by the compounding of glycerin and higher fatty acid in molar ratio 1:3, and higher fatty acid is the combination of palmitic acid, stearic acid, oleic acid, linoleic acid, The molar ratio is 1.5:1:2:0.5. The conditioner is a combination of cyclohexane and tetrachloromethane, the molar ratio is 1:1.

Embodiment 2

[0037] The carbon dioxide is heated to 63°C in the room, and the pressure rises to 20MPa. Take 0.1% viscosity increasing agent and 0.3% conditioning agent and add to 99.6% carbon dioxide through closed injection equipment, stir and dissolve to prepare supercritical carbon dioxide fracturing fluid system. The system has passed the temperature and shear resistance test, and the viscosity value fluctuates within 4-8mPa·s, see the attached figure 2 .

[0038] The above percentages are all percentages by mass. The viscosity-raising agent is a higher fatty acid fat, which is formed by combining glycerin and a higher fatty acid in a molar ratio of 1:2. The higher fatty acid is a combination of palmitic acid, stearic acid, oleic acid, and linolenic acid. The ratio is 1:1:1:0.2. The conditioner is a combination of cycloheptane, tetrachloromethane and difluorodichloromethane, and the molar ratio is 1:1:1.

Embodiment 3

[0040] The carbon dioxide is heated to 63°C in the room, and the pressure rises to 20MPa. Take 2% viscosity increasing agent and 2% conditioning agent and add them into 96% carbon dioxide through closed injection equipment, stir and dissolve to prepare a supercritical carbon dioxide fracturing fluid system. The system has been tested for temperature resistance and shear resistance, and the viscosity value fluctuates within 6-10mPa·s, see the attached image 3 .

[0041] The above percentages are all percentages by mass. Described viscosifying agent is higher fatty acid fat, and it is formed by the compounding of glycerol and higher fatty acid in molar ratio 1:1, and higher fatty acid is the combination of palmitic acid, oleic acid, linoleic acid, ricinoleic acid , the molar ratio is 1:1:1:10. The conditioner is a combination of cyclohexane, dicyclodecane, tetrachloromethane and difluorodichloromethane, and the molar ratio is 1:1:1:1.

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 relates to a supercritical carbon dioxide based fracturing liquid system and application thereof. The fracturing liquid system comprises the following components: 0.1%-5% of adhesive, 0.3%-6.5% of conditioner and the rest of supercritical carbon dioxide. The supercritical carbon dioxide based fracturing liquid system provided by the invention can be used for oil field fracturing. In an application field, all components are mixed in certain mass percentage, and a propping agent is pumped into a stratum together with the mixture. The fracturing liquid system provided by the invention has the characteristics of good sand-carrying properties, easy backflow, no residues and no water phase, completely eliminates water-lock and water-sensitive damages, effectively reduces the viscosity of crude oil, inhibits clay swelling, improves the reservoir permeability, greatly saves water resources and can reach the purpose of efficient, environment-friendly and green construction.

Description

technical field [0001] The invention relates to a fracturing fluid system based on supercritical carbon dioxide and its application. The fracturing fluid system can be used for oilfield fracturing. Background technique [0002] Fracturing has been developed rapidly and widely used as the main production and injection measures of oil and gas reservoirs, and fracturing fluid is an important part of fracturing technology. At present, the most commonly used fracturing fluid at home and abroad is water-based fracturing fluid, which has achieved good production stimulation effects. However, these fracturing fluid systems have disadvantages, such as the incomplete gel breaking of the fracturing fluid, and the residue will remain in the fracture after the gel is broken, and the polymer remaining in the fracture will seriously reduce the permeability of the proppant packing layer, thus damaging the production layer, leading to poor fracturing effect. [0003] In addition, for wate...

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): C09K8/64E21B43/26
CPCC09K8/62E21B43/26Y02P20/54
Inventor 宋振云张劲李勇吴冲汪小宇孟思炜李志航王所良周然杨发苏伟东文果陈迎花王玉功李童金娜
Owner CHINA NAT PETROLEUM CORP CHUANQING DRILLING ENG 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