Drilling fluid capable of protecting coal bed methane reservoir

A drilling fluid and coalbed methane technology, applied in the direction of drilling compositions, instruments, analysis materials, etc., can solve the damage of coalbed methane reservoirs, fail to effectively protect the stability of coalbed methane well walls in coalbed methane reservoirs, reduce storage problems such as layer permeability, to prevent hydration, enhance promotion and application value, and maintain stability

Inactive Publication Date: 2013-07-10
CHINA UNIV OF PETROLEUM (EAST CHINA)
View PDF8 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The invention provides a drilling fluid for protecting coalbed methane reservoirs, aiming at solving the serious damage of the current drilling fluid to the coalbed methane reservoirs during the drilling process of the coalbed methane reservoirs, reducing the permeability of the reservoirs, Insufficient desorption of coalbed methane, failure to effectively protect the coalbed methane reservoir and maintain the stability of the coalbed well wall

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
  • Drilling fluid capable of protecting coal bed methane reservoir
  • Drilling fluid capable of protecting coal bed methane reservoir

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach

[0060] Specific embodiments: The experimental methods adopted in the following specific examples are conventional methods unless otherwise specified.

[0061] The materials and reagents used in the following specific examples can be obtained from commercial sources unless otherwise specified.

[0062] Sodium hydroxide and potassium hydroxide in the pH regulator in the following specific examples of the present invention were purchased from Jinan Century Lianxing Economic and Trade Co., Ltd., and sodium carbonate and sodium bicarbonate were purchased from Jinan CITIC Chemical Co., Ltd.

[0063] Sodium chloride, potassium chloride, calcium chloride, and magnesium chloride in the water-sensitivity inhibitors in the following specific examples of the present invention were all purchased from Jinan Xintongchuang Chemical Co., Ltd.

[0064] The polyoxyethylene alkylphenol ether in the waterproof locking agent in the following specific examples of the present invention was purchased ...

example 1

[0066] Example 1: Preparation of Drilling Fluid for Protecting Coalbed Methane Reservoirs

[0067] Formula 1: 400mL fresh water, 0.60g sodium carbonate, 0.40g sodium hydroxide, 12.00 water sensitivity inhibitor (sodium chloride), 1.20g waterproof lock agent (polyoxyethylene alkylphenol ether, polyoxyethylene octylphenol ether The mass ratio of polyether diamine and polyether diamine in the preparation is 3:5:2).

[0068] According to the composition of formula 1, under low-speed (600rpm) stirring conditions, add sodium carbonate, sodium hydroxide, water-sensitivity inhibitor, and waterproof lock agent to fresh water in sequence to obtain the drilling fluid for protecting the coalbed methane reservoir, which is recorded as 1 #drilling fluid.

example 2

[0069] Example 2: Preparation of Drilling Fluid for Protecting Coalbed Methane Reservoirs

[0070] Formula 2: 400mL of fresh water, 0.60g of sodium carbonate, 0.40g of sodium hydroxide, 14.00g of water-sensitive inhibitor (the mass ratio of sodium chloride to calcium chloride is 6:1), 1.20g of waterproof locking agent (polyoxyethylene alkanes The mass ratio of base phenol ether, polyoxyethylene octyl phenol ether and polyether diamine during preparation is 2:5:3).

[0071] According to the composition of formula 2, under low-speed (600rpm) stirring conditions, add sodium carbonate, sodium hydroxide, water-sensitivity inhibitor, and waterproof locking agent to the fresh water in sequence to obtain the drilling fluid for protecting the coalbed methane reservoir, which is recorded as 2 #drilling fluid.

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
densityaaaaaaaaaa
recovery rateaaaaaaaaaa
recovery rateaaaaaaaaaa
Login to view more

Abstract

The invention discloses a drilling fluid capable of protecting a coal bed methane reservoir. The drilling fluid comprises the following ingredients in percentage by weight: 100 parts of fresh water, 0.1-0.3 part of pH value modifier, 0.5-10 parts of water-sensitivity inhibitor, and 0.1-1 part of waterproof blocking agent. For the drilling fluid, the density is 1.01-1.08g/cm<3>, the pH value ranges 8 to 10, the expansion rate reduction ratio is greater than or equal to 60%, the contact angle reduction rate is greater than or equal to 50%, the hygroscopic-state recovery rate of the core permeability is greater than or equal to 85%, the dry-state recovery rate is greater than or equal to 95%, the coal powder landberra volume reduction rate is greater than or equal to 15%, clay-free phase does not exist, the damage to the coal bed methane reservoir caused by same-phase invasion can be furthest reduced, the hydration of the clay mineral in coal petrography can be effectively prevented, water blocking is reduced, the coal bed methane can be forced to be desorbed from the surface of the coal petrography, the coal bed methane reservoir can be effectively protected, the stability of the coal bed well wall can be retained, the practicability is strong, and the stronger popularization and application values can be achieved.

Description

technical field [0001] The invention belongs to the technical field of oil and natural gas drilling fluids, in particular to a drilling fluid for protecting coalbed gas reservoirs. Background technique [0002] Coalbed methane is a kind of unconventional natural gas resource that is self-generated and self-storage in the coal seam itself, and its main component is methane. my country's coalbed methane resources are about 36.81 trillion m 3 , is three times that of the United States, and is equivalent to the amount of conventional onshore natural gas resources. In recent years, efforts have been made to explore and develop coalbed methane, but the industrial scale and commercial value have not yet formed, and many technical difficulties have been encountered. Reservoir protection Questions are one of them. Coalbed methane reservoirs are very different from conventional sandstone and carbonate reservoirs. They have high adsorption, low permeability, and are easy to be compre...

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): C09K8/12G01N7/04
Inventor 黄维安邱正松马永乐钟汉毅江琳曹杰白雪飞
Owner CHINA UNIV OF PETROLEUM (EAST CHINA)
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