Anti-collapse drilling fluid for coal bed methane horizontal well and method for preparing anti-collapse drilling fluid

A technology for horizontal wells and coalbed methane, which is applied in the directions of chemical instruments and methods, drilling compositions, etc., can solve the problems of difficult degradation and easy blocking of water and gas production channels in coal seams, so as to reduce surface tension, reduce coal seam pollution, and prevent inflated effect

Active Publication Date: 2012-12-05
PETROCHINA CO LTD
View PDF5 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

After the formula ingredients in this patent enter the coal seam, it fills its cleat system and is difficult to degrade, and it is easy

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

[0027] Embodiment 1: Coalbed gas horizontal well anti-collapse drilling fluid, the weight percentage of each component is:

[0028] 1. Potassium polyacrylate: 0.3%;

[0029] 2. Sodium lignosulfonate: 0.2%;

[0030] 3. GHA-5 coal water slurry additive: 0.1%;

[0031] 4. Potassium chloride: 2%;

[0032] 5. Potassium humate: 0.5%;

[0033] 6. Sulfonated lignite: 0.5%;

[0034] 7. Graphite powder: 1%;

[0035] 8. The rest is water (95.4%), and the sum of the weight percentages of each component is 100%.

[0036] Preparation process: First, add potassium chloride to clean water, stir evenly, and let it stand for 10 hours to form a base slurry; secondly, add potassium polyacrylate, sodium lignosulfonate, and GHA-5 type water coal to the base slurry in sequence in proportion slurry additive and potassium humate, and stir evenly; finally, add sulfonated lignite and graphite powder under continuous stirring, and stir evenly to obtain the anti-collapse drilling fluid for coalbed m...

Embodiment 2

[0038] Embodiment 2: The anti-collapse drilling fluid for coalbed methane horizontal wells, the weight percentage of each component is:

[0039] 1. Potassium polyacrylate: 0.2%;

[0040] 2. Sodium lignosulfonate: 0.2%;

[0041] 3. GHA-5 coal water slurry additive: 0.3%;

[0042] 4. Potassium chloride: 3%;

[0043] 5. Potassium humate: 0.5%;

[0044] 6. Sulfonated lignite: 0.5%;

[0045] 7. Graphite powder: 1%;

[0046] 8. The rest is water (94.3%), and the sum of the weight percentages of each component is 100%.

[0047] The preparation method is the same as in Example 1.

[0048] Example 2 Application effect of anti-collapse drilling fluid in coalbed methane horizontal wells: Well Zheng 4ping-8H enters the coal seam and then drills into the M1 main branch with clean water. When the drilling footage is 630 meters, the torque increases. Drilling fluid with a potassium chloride concentration of 3% was used to drill until completion. The total footage of the well was 5,036...

Embodiment 3

[0049] Embodiment 3: The anti-collapse drilling fluid for coalbed methane horizontal wells, the weight percentage of each component is:

[0050] 1. Potassium polyacrylate: 0.2%;

[0051] 2. Sodium lignosulfonate: 0.4%;

[0052]3. GHA-5 coal water slurry additive: 0.2%;

[0053] 4. Potassium chloride: 1%;

[0054] 5. Potassium humate: 0.6%;

[0055] 6. Sulfonated lignite: 0.4%;

[0056] 7. Graphite powder: 2%;

[0057] 8. The rest is water, and the sum of the weight percentages of each component is 100%.

[0058] The preparation method is the same as in Example 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 provides anti-collapse drilling fluid for coal bed methane horizontal well. The drilling fluid is used for preventing the collapse of the wall of the well in the well drilling process. The drilling fluid is characterized by comprising the following components in percentage by weight: 0.1 to 0.3 percent of potassium polyacrylate, 0.1 to 0.5 percent of sodium lignosulfonates, 0.1 to 0.3 percent of GHA-5 type coal water slurry additive, 0.5 to 3 percent of potassium chloride, 0.4 to 0.6 percent of potassium humate, 0.3 to 0.5 percent of sulfonated lignite, 1 to 3 percent of graphite powder and the balance of water. The sum of weight percent of the components is 100 percent. The drilling fluid has the advantages of effectively preventing the expansion of the coal matrix, inhibiting the collapse of the wall of the well due to the immersion of the coal bed in clean water, dissolving macromolecules adsorbed in the coal bed, lowering the surface tension of the coal matrix on the premises of keeping the normal physical characteristics unchanged, facilitating the flowback of the drilling fluid and lowering the pollution of the coal bed; the drilling fluid is prevented from being absorbed on the surface of coal, so that a gas channel cannot be blocked; and by adjusting the proportion of additives, the well-drilling construction is guaranteed.

Description

technical field [0001] The invention relates to the technical field of coalbed methane horizontal well drilling, in particular to a drilling fluid used for suppressing borehole wall collapse during the drilling process of coalbed methane horizontal wells. Background technique [0002] In order to prevent the well wall from collapsing during the drilling of coalbed methane horizontal wells, it is generally used to add proppant to the drilling fluid to enhance the stability of the well wall. The commonly used proppants include various polymers and other patented products. This method can effectively enhance the stability of the borehole wall, avoid accidents such as drill sticking and buried drill during the drilling process, and ensure the smooth progress of drilling construction. During the actual application, it was found that although the proppant can stabilize the well wall, due to the unique adsorption and low permeability of the coal seam, the drilling fluid is adsorbed...

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): C09K8/12C09K8/575
Inventor 周立春马辉张聪余巍
Owner PETROCHINA 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