Anti-water-blocking agent for drilling fluid and preparation method thereof

A technology for waterproof locking agent and drilling fluid, which is applied in chemical instruments and methods, drilling compositions, etc., can solve the problem of unfavorable release of water locking effect of stagnant fluid near wellbore, and cannot effectively reduce filtrate surface tension and oil-water interfacial tension. , the problem of poor drainage effect of invading liquid, etc., to reduce the surface tension of the solution and the interfacial tension of oil and water, the preparation method is safe and economical, and the conversion rate is high.

Active Publication Date: 2013-01-23
CHINA UNIV OF PETROLEUM (BEIJING)
View PDF1 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, for oil and gas reservoirs with complex geological conditions such as low porosity and low permeability, these traditional waterproof locking agents are difficult to meet the requirements: (1) cannot effectively reduce the surface tension of the filtrate and the interfacial tension of oil and water to increase the relative permeability of the gas phase; ( 2) The drainage effect on the intrusive fluid is not good, which is not conducive to the retention fluid near the wellbore being driven away by drainage to better relieve the water lock effect

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
  • Anti-water-blocking agent for drilling fluid and preparation method thereof
  • Anti-water-blocking agent for drilling fluid and preparation method thereof
  • Anti-water-blocking agent for drilling fluid and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] A preparation method for drilling fluid waterproof locking agent, it comprises the steps:

[0035] 1) Disperse the four monomers of butyl acrylate, methyl methacrylate, acrylamide and methacrylic acid in water at a ratio of 5:4:1:1, add 2% emulsifier, and shear and stir for 30 minutes to obtain a mixture Solution A, the mass concentration of A solution is 20%.

[0036] 2) The synthesis temperature of the mixed solution A is 70°C. Before the synthesis, nitrogen protection is introduced. When the temperature of the solution rises to 70°C, an initiator is added, and the reaction is kept for 1 hour. The initiator is potassium persulfate, and the dosage is 1% of the total amount of monomers. 0.02%. The resulting solution is B.

[0037] 3) Slowly add tridecafluorooctyl methacrylate with 18% of the total amount of monomers in step 1) dropwise to solution B, an emulsifier with 0.5% of the total amount of monomers in step 1) and the total amount of monomers in step 1) Add 0.0...

Embodiment 2

[0040] A preparation method for drilling fluid waterproof locking agent, it comprises the steps:

[0041]1) Disperse the four monomers of butyl acrylate, methyl methacrylate, acrylamide and methacrylic acid in water at a ratio of 4:4:1:1, add 2.25% emulsifier, and shear and stir for 30 minutes to obtain a mixture Solution A, the mass concentration of A solution is 25%.

[0042] 2) The synthesis temperature of the mixed solution A is 70°C. Before the synthesis, nitrogen protection is introduced. When the temperature of the solution rises to 70°C, the initiator is added, and the reaction is kept for 1 hour. The initiator is potassium persulfate, and the dosage is 1% of the total amount of monomers. 0.08%. The resulting solution is B.

[0043] 3) Slowly add tridecafluorooctyl methacrylate with 21% of the total amount of monomers in step 1) to solution B, an emulsifier with 0.4% of the total amount of monomers in step 1) and the total amount of monomers in step 1) The amount of...

Embodiment 3

[0046] A preparation method for drilling fluid waterproof locking agent, it comprises the steps:

[0047] 1) Disperse the four monomers of butyl acrylate, methyl methacrylate, acrylamide and methacrylic acid in water at a ratio of 4:3:1:1, add 2.5% emulsifier, and shear and stir for 30 minutes to obtain a mixture Solution A, the mass concentration of A solution is 30%.

[0048] 2) The synthesis temperature of the mixed solution A is 70°C. Before the synthesis, nitrogen protection is introduced. When the temperature of the solution rises to 70°C, the initiator is added, and the reaction is kept for 1 hour. The initiator is potassium persulfate, and the dosage is 1% of the total amount of monomers. 0.1%. The resulting solution is B.

[0049] 3) Slowly add tridecafluorooctyl methacrylate of 25% of the total amount of monomers in step 1) to solution B, an emulsifier of 0.6% of the total amount of monomers in step 1) and the total amount of monomers in step 1) Add 0.05% of the i...

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
surface tensionaaaaaaaaaa
surface tensionaaaaaaaaaa
Login to view more

Abstract

The invention relates to an anti-water-blocking agent for drilling fluid and a preparation method thereof. The anti-water-blocking agent is a polymer containing a butyl acrylate (BA) monomer, a methyl methacrylate (MMA) monomer, a methacrylic acid (MAA) monomer, an acrylamide (AM) monomer and a 2-(perfluorohexyl)ethyl methacrylate (G06B) monomer, wherein the mol percent of a is 35.8-36.5%, the mol percent of b is 27.0-30.5%, the mol percent of c is 7.5-9.0% and the mol percent of d is 7.5-9.0%. According to the invention, the anti-water-blocking agent effectively reduces filtrate surface tension and oil-water interfacial tension, improves gas-phase relative permeability, has a good invading fluid draining effect and is beneficial to driving away resident fluid in near wellbore formations in a draining manner so as to better relieve the water blocking effect. The preparation method of the anti-water-blocking agent is safe and economic and has a high conversion rate; and a batch feeding method is used, so that the requirements for low dosage and high performance are met.

Description

technical field [0001] The invention belongs to the field of drilling fluid additives, and in particular relates to a waterproof locking agent for reducing water-locking damage of oil and gas reservoirs, reducing the surface tension of drilling fluid filtrate, improving gas-phase permeability of rock cores, and protecting reservoirs, and a preparation method thereof. Background technique [0002] Low-porosity and low-permeability oil and gas reservoirs generally have high muddy cement content, high water saturation, high capillary pressure, strong water sensitivity, small pore throat, poor permeability, complex structure, serious heterogeneity, and large oil and gas flow resistance, etc. features. A large number of studies have shown that water lock damage is the most important and serious damage type of this type of reservoir, and the damage rate is generally 70%-90%. Drilling fluid is the first foreign fluid in contact with the reservoir, and its filtrate intrusion into t...

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): C08F220/18C08F220/14C08F220/56C08F220/06C08F220/22C08F2/26C08F2/28C09K8/035
Inventor 蒋官澄李颖颖黎凌
Owner CHINA UNIV OF PETROLEUM (BEIJING)
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