Unlock instant, AI-driven research and patent intelligence for your innovation.

Low-friction temporary plugging diverting acid system

A technology of turning to acid and low friction, which is applied in the direction of drilling compositions, chemical instruments and methods, etc., which can solve the problems of poor acidification effect and high pumping pressure, and achieve the effect of reducing friction

Inactive Publication Date: 2020-07-14
CNPC BOHAI DRILLING ENG +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to provide a low-friction temporary plugging and diverting acid system, which overcomes the fact that the conventional coiled tubing a

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
  • Low-friction temporary plugging diverting acid system
  • Low-friction temporary plugging diverting acid system
  • Low-friction temporary plugging diverting acid system

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0022] The preparation method of described drag reducer:

[0023] (1) Preparation of the water phase: add 3% to 4% of itaconic acid and 30% to 32% of acrylamide in deionized water, and after it is completely dissolved, add 0.02% to 0.03% of EDTA·2Na, 0.04% to 0.06% Urea, 5%-6% TMEDA, and then adding acetic acid to adjust the pH value to 5-6 to obtain an aqueous phase solution, and the percentages are mass percentages;

[0024] (2) Preparation of oil phase: mix Span80, Tween20 and white oil in a mass ratio of 1:1:18-20, stir evenly at 100r / min to obtain an oil phase solution;

[0025] (3) Add the prepared water phase solution to the oil phase solution drop by drop. The mass ratio of oil to water is 3:7. At the same time, nitrogen gas is introduced to exhaust the oxygen. %~0.04% azobisisobutylimidazoline hydrochloride, the temperature is raised to 50°C for 2 hours, and then the temperature is raised to 65°C to continue the reaction for 3 hours to complete the reaction;

[0026...

Embodiment 1

[0035] The basic formula of the low-friction temporary blocking diverting acid system is: 15% HCl + 5% diverting agent (oleic acid amidopropyl betaine) + 1% temporary blocking agent + 1% corrosion inhibitor + 0.1% drag reducer + 0.2% Drainage aid + 2% iron ion stabilizer + 2% anti-acid slag agent (ethylene glycol monobutyl ether (EGMBE)).

[0036] The preparation method of described drag reducer:

[0037] (1) Preparation of water phase: add deionized water, mass ratio 3% IA, then add mass ratio 30% AM, after completely dissolving, add mass ratio 0.02% EDTA·2Na, mass ratio 0.04% urea, mass ratio 5 %TMEDA, then add acetic acid to adjust the pH value to 5-6;

[0038] (2) Preparation of oil phase: Mix Span80, Tween20 and white oil in a mass ratio of 1:1:20, stir evenly at 100 r / min to obtain an oil phase solution.

[0039] (3) Add the prepared water phase to the oil phase drop by drop (the mass ratio of oil to water is 3:7), and at the same time pass nitrogen to exhaust oxygen. ...

Embodiment 2

[0042] The basic formula of low-friction temporary blocking diverting acid system is: 20% HCl+4% diverting agent (oleic amidopropyl betaine)+2% temporary blocking agent+1.5% corrosion inhibitor+0.1% drag reducer+0.1% Drainage aid + 1.5% iron ion stabilizer + 2% anti-acid slag agent (ethylene glycol monobutyl ether (EGMBE)).

[0043] The preparation method of described drag reducer:

[0044] (1) Preparation of water phase: add deionized water, mass ratio 4% IA, then add mass ratio 32% AM, after completely dissolving, add mass ratio 0.03% EDTA·2Na, mass ratio 0.06% urea, mass ratio 6 %TMEDA, then add acetic acid to adjust the pH value to 6;

[0045] (2) Preparation of oil phase: Mix Span80, Tween20 and white oil at a mass ratio of 1:1:18, stir evenly at 100 r / min to obtain an oil phase solution.

[0046] (3) Add the prepared water phase to the oil phase drop by drop (the mass ratio of oil to water is 3:7), and at the same time pass nitrogen to exhaust oxygen. After the water p...

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 discloses a low-friction temporary plugging diverting acid system. The low-friction temporary plugging diverting acid system comprises the following components in percentage by mass: 15%-20% of HCl, 4%-6% of a diverting agent, 1%-2% of a degradable temporary plugging agent, 1%-2% of a corrosion inhibitor, 0.1%-0.2% of a drag reducer, 0.1%-0.3% of a cleanup additive, 0.5%-1.0% of an iron ion stabilizer, 0.5%-1.5% of an acid sludge inhibitor and the balance of water. According to the invention, the drag reducer with good compatibility is added into the acid liquid system, so that the friction resistance of the acid liquid during flowing and the pumping pressure of the coiled tubing are reduced. The degradable temporary plugging agent is added into a conventional self-divertingacid system, when a stratum with cracks develops, the cracks can be effectively plugged under the synergistic effect of diverting acid and the temporary plugging agent, and therefore the purpose of uniform acidification is achieved.

Description

technical field [0001] The invention relates to the technical field of oilfield acidizing construction operations, in particular to a low-friction temporary plugging and diverting acid system. Background technique [0002] Coiled tubing has the advantages of simple operation, low labor intensity, short operation time, and few accidents. Its high degree of integration and small footprint of equipment greatly shorten the operation cycle. Using coiled tubing operation technology for dragging acidizing construction can effectively improve the efficiency of acidizing construction and reduce production costs. However, the coiled tubing has a small diameter, and the conventional steering acid operation has the disadvantages of large acid fluid friction and high pumping pressure, and the conventional acid fluid system cannot achieve the purpose of uniform acid distribution in severely heterogeneous formations. Contents of the invention [0003] The technical problem to be solved ...

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): C09K8/508C09K8/514C09K8/74C09K8/72
CPCC09K8/5086C09K8/514C09K8/725C09K8/74C09K2208/26C09K2208/28C09K2208/30C09K2208/32
Inventor 张朔李旭东张乾向兆东刘德正杜承强杨志马超汪强杨翠华张龙
Owner CNPC BOHAI DRILLING ENG