Horizontal well drilling fluid for protecting coal bed gas reservoir

A technology for horizontal wells and coalbed methane, applied in the field of horizontal well drilling fluids, can solve the problems of solid phase blockage of fine coal dust, low salinity of clear water, hydration expansion of clay minerals, etc., to reduce blockage damage, strong interface activity, The effect of strong flocculation ability

Inactive Publication Date: 2014-01-22
YANGTZE UNIVERSITY
View PDF2 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, clear water drilling fluid also has the following disadvantages: 1. The salinity of clear water is low, which can easily cause the hydration and expansion of clay minerals in the coal seam, thereby blocking the seepage channel of coalbed methane; 2. The clean water from the surface and the underground Coal seam water is incompatible and scaling phenomenon exists; 3. In the case of positive pressure difference drilling, the flowback ability of clean water intruded into low permeability coal seams is weak, which is extremely unfavorable for the drainage and mining of coalbed methane in the later stage; 4. The clear water flocculation ability is weak and cannot be The fine coal chips broken by the drill bit are removed in time, which will cause the fine coal chips to invade the coal seam and cause solid phase blockage

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
  • Horizontal well drilling fluid for protecting coal bed gas reservoir

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] A kind of horizontal well drilling fluid for protecting the coalbed methane reservoir provided by the present invention, the weight percentage of each component is based on the weight of 100% water, and the percentage of each additive accounting for the weight of water is:

[0024] Anti-swelling agent: 0.2%; drainage aid: 0.05%; anti-scaling agent: 0.001%; ​​flocculant: 0.2%.

[0025] Preparation method: Since the above-mentioned additives are small molecular or low molecular chemical substances, the dissolution is relatively fast and the preparation is simple. All the components are fully dissolved in water and then mixed.

Embodiment 2

[0027] A kind of horizontal well drilling fluid for protecting the coalbed methane reservoir provided by the present invention, the weight percentage of each component is based on the weight of 100% water, and the percentage of each additive accounting for the weight of water is:

[0028] Anti-swelling agent: 0.3%; drainage aid: 0.05%; anti-scaling agent: 0.003%; flocculant: 0.5%.

[0029] Preparation method: Since the above-mentioned additives are small molecular or low molecular chemical substances, the dissolution is relatively fast and the preparation is simple. All the components are fully dissolved in water and then mixed.

Embodiment 3

[0031] A kind of horizontal well drilling fluid for protecting the coalbed methane reservoir provided by the present invention, the weight percentage of each component is based on the weight of 100% water, and the percentage of each additive accounting for the weight of water is:

[0032] Anti-swelling agent: 0.5%; drainage aid: 0.1%; anti-scaling agent: 0.005%; flocculant: 0.4%.

[0033] Preparation method: Since the above-mentioned additives are small molecular or low molecular chemical substances, the dissolution is relatively fast and the preparation is simple. All the components are fully dissolved in water and then mixed.

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 horizontal well drilling fluid for protecting a coal bed gas reservoir, belonging to the technical field of chemical agents of coal bed gas exploitation engineering. The horizontal well drilling fluid is characterized by comprising water, an anti-swelling agent, a discharge aiding agent, an anti-scaling agent and a flocculating agent; on the basis of the weight of 100% of water in percentage by weight, the anti-swelling agent accounts for 0.2-0.5%, the discharge aiding agent accounts for 0.05-0.1%, the anti-scaling agent accounts for 0.001-0.005%, and the flocculating agent accounts for 0.2-0.5%. The anti-swelling agent is industrial grade potassium chloride, and the discharge aiding agent is nonylphenol polyoxyethylene ether OP-10; the anti-scaling agent is 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP); the flocculating agent is liquid poly aluminum chloride (PAC). The horizontal well drilling fluid disclosed by the invention has appropriate degree of mineralization, can not form scales after being mixed with coal bed water, is low in surface tension and strong in interfacial activity, can flow back easily after invading a low-permeability coal bed, and has the characteristics of good compatibleness with the coal bed, strong flocculation ability, low cost and environment-friendliness.

Description

Technical field: [0001] The invention relates to a horizontal well drilling fluid for protecting coalbed methane reservoirs, and belongs to the technical field of engineering chemical agents for coalbed methane exploitation. Background technique: [0002] As my country's demand for energy is increasing, coalbed methane as one of the unconventional natural gas (coalbed methane, shale gas, tight sandstone gas and gas hydrate) is getting more and more attention. At present, the exploitation of coalbed methane in my country has been into a flourishing stage. [0003] Compared with foreign coalbed methane, my country's coalbed methane has its own special features, that is, the characteristics of low porosity and low permeability of coal seams, that is, low single well production. This low production characteristic also determines the low-cost strategy of my country's coalbed methane development. The use of horizontal wells for coalbed methane mining is becoming more and more wide...

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): C09K8/12
CPCC09K8/12C09K2208/12
Inventor 岳前升田中兰蒋光忠陈军杨恒林胡友林汪伟英
Owner YANGTZE UNIVERSITY
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