A temperature-responsive self-degrading temporary plugging agent and workover method

A temperature-responsive, self-degrading technology, applied in chemical instruments and methods, drilling compositions, etc., can solve problems such as complex processes, large rubber plugs, and complex and tedious construction processes.

Active Publication Date: 2022-03-01
YANGTZE UNIVERSITY
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, existing liquid rubber stoppers also have the problem of difficulty in breaking the gel and degrading
Chinese patent CN105131917A discloses a degradable liquid rubber stopper, which consists of carboxymethyl guar gum, γ-aminopropyltriethoxysilane and cetyltrimethylammonium bromide. , it is necessary to pump ammonium persulfate solution into the wellbore to break the gel, and the construction process is complicated and cumbersome; Chinese patent CN106905940A discloses a medium-high density elastic liquid plug and a workover method. Only when the rubber plug breaks into elastic rubber plug particles can it be degraded, and then the saline well killing fluid is used for circulation flushing, the process is complex
If the damage of the rubber plug is uneven, it is easy to form a large rubber plug, which increases the difficulty of post-processing

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
  • A temperature-responsive self-degrading temporary plugging agent and workover method
  • A temperature-responsive self-degrading temporary plugging agent and workover method
  • A temperature-responsive self-degrading temporary plugging agent and workover method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0045] First, take by weighing 5g of acrylamide, 0.3g of polyethylene glycol 600 diacrylate, 0.5g of ammonium persulfate, and 0.25g of AMP-95 in 93.95mL of water to prepare a temperature-responsive self-degradation temporary plugging agent; The polyacrylamide aqueous solution with a mass fraction of 3‰ was used as pre-fluid and post-fluid.

[0046] Inject 10mL of 3‰ polyacrylamide aqueous solution and 20mL temperature-responsive self-degrading temporary plugging agent in sequence into the 2000mD permeability core (simulated oil and gas well), and inject 20mL of 3‰ polyacrylamide aqueous solution after the gel is broken and observe the injection pressure in real time Then put the cores into 50℃, 60℃, 70℃, and 80℃ constant temperature ovens to test the temperature resistance of the temporary plugging agent. The experimental results are as follows figure 1 As shown, the influence of temperature on the gelation time and gel breaking time of the temperature-responsive self-degradin...

Embodiment 2

[0050] First weigh 4g of acrylamide, 0.1g of polyethylene glycol 600 diacrylate, 0.2g of ammonium persulfate, and 0.25g of AMP-95 in 95.45mL of water to prepare a temporary plugging agent solution; Aqueous acrylamide solution was used as pre-fluid and post-fluid.

[0051] Inject 10mL of 4‰ polyacrylamide aqueous solution, 20mL of temperature-responsive self-degrading temporary plugging agent, and 20mL of 4‰ polyacrylamide aqueous solution into the 2000mD permeability core (simulated oil and gas well), and react in a constant temperature oven at 60°C for 4 hours After gelation, the core was taken out and used in the displacement device to test the breakthrough pressure of the temporary plugging agent by water flooding and gas flooding reverse displacement respectively. The experimental results are as follows: figure 2 As shown, it can be seen from the experimental results that the breakthrough pressure of the temporary plugging agent is up to 5MPa and 5.5MPa when the core is r...

Embodiment 3

[0053] First, weigh 4g of acrylamide, 0.8g of polyethylene glycol 600 diacrylate, 1g of ammonium persulfate, respectively 0.1g, 0.2g, 0.3g, 0.4g, 0.5g of AMP-95 in water to prepare temporary plugging The mass fraction of acrylamide in the temporary plugging agent solution is 4%, the mass fraction of polyethylene glycol 600 diacrylate is 0.8%, the mass fraction of ammonium persulfate is 1%, and the mass fraction of AMP-95 is respectively 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, to test the effect of different degradation catalyst additions on the gel breaking time of the temperature-responsive self-degrading temporary plugging agent, and use the visual method to check the gel breaking time of the temporary plugging agent. Observation records, using the gel strength code method to represent the strength change of the gel temporary plugging agent, the experimental results are shown in Table 2. From the experimental results, it can be known that the composition of the temperature-responsive s...

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
viscosityaaaaaaaaaa
Login to view more

Abstract

The invention provides a temperature-responsive self-degradation temporary plugging agent and a workover method, belonging to the technical field of oil and gas exploitation. Components comprising the following mass percentages: Components comprising the following mass percentages: 4% to 6% of vinyl-containing monomers, 0.1% to 1% of crosslinking agents, 0.1% to 1% of initiators , 0.05% to 0.5% of the degradation catalyst and the rest of the water, the cross-linking agent is polyethylene glycol diacrylate, the degradation catalyst is 2-amino-2-methyl-1-propanol or ethylene glycol Alcoholamine. In the present invention, polyethylene glycol diacrylate is used as a crosslinking agent, and 2-amino-2-methyl-1-propanol or ethylene glycol amine is used as a degradation catalyst. Maintain strength for a period of time, and then as time goes by, polyethylene glycol diacrylate will fail to cross-link under the action of a degradation catalyst, degrading the gel temporary plugging agent into a linear polymer, and finally reduce the viscosity to realize self-degradation of the gel .

Description

technical field [0001] The invention relates to the technical field of oil and gas exploitation, in particular to a temperature-responsive self-degradation temporary plugging agent and a workover method. Background technique [0002] In order to cope with the failures that may occur in oil and gas wells during the oil and gas production process, it is necessary to carry out workover operations to remove the failures and resume normal production operations. However, when oil and gas wells are in workover operations, the pressure difference will cause different degrees of workover fluid leakage, which not only hinders the normal workover operations, but also pollutes the formation. Therefore, how to take effective measures to realize the temporary plugging of the wellbore and successfully flow back the temporary plugging fluid after the completion of the workover operation has important practical significance. [0003] In recent years, liquid rubber plugs have been researched...

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 Patents(China)
IPC IPC(8): C08F290/06C08F220/56C08F222/38C08F220/06C09K8/512C09K8/88
CPCC08F290/062C09K8/512C09K8/5083C09K8/887C09K8/882C08F220/56C08F222/385C08F220/06
Inventor 李强于小荣秦少雄杨欢苏高申艾柳强严涵刘冲
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