Plugging agent for drilling fluid and preparation method thereof

Abstract

The invention discloses a plugging agent for drilling fluid and a preparation method thereof. The plugging agent is prepared from the following components in parts by weight: 100 parts of matrix asphalt, 10-40 parts of a microcapsule modifier, 1-20 parts of a dispersing agent, 5-20 parts of a curing agent, 0.5-5 parts of an accelerant and 100-200 parts of water. The plugging agent can effectively reside at entrances of malignant leakage strata such as large cracks and karst caves to form solid sealing, and particularly, the retention plugging capacity and the water washing resistance are improved at high temperature and high pressure, so that the plugging success rate is increased.

Description

technical field

[0001] The invention relates to the field of oil drilling plugging, in particular to a plugging agent for drilling fluid and its preparation. Background technique

[0002] In the oil and gas drilling process, lost circulation is a ubiquitous and often encountered complex problem. Downhole accidents caused by lost circulation are extremely harmful to drilling and completion, and have always been an urgent problem to be solved in the field of petroleum engineering. During drilling operations, once lost circulation occurs, it will not only delay time, lose drilling fluid, and damage oil and gas layers, but also may cause well wall instability, leading to a series of complex situations and accidents such as well collapse, pipe sticking, and blowout, and even lead to wellbore failure. scrapped, resulting in significant economic losses.

[0003] Especially in the process of drilling deep oil and gas wells in alpine areas, the number of large fractures and karst-v...

Examples

Embodiment 1

[0044]Dissolve 25g of polysulfone in methylene chloride, then add a mixture of 79g of CYD-128 epoxy resin and 3.8g of benzyl alcohol, stir evenly to form a dispersed phase; use 1.0% sodium dodecylbenzenesulfonate aqueous solution as the continuous phase, The above-mentioned dispersed phase is added dropwise into the continuous phase while stirring at a high speed at a speed of 2600 r / min. After the dropwise addition, react in a constant temperature water bath at 40° C. for 5.5 hours while stirring at a low speed at 600 r / min. After the complete volatilization reaction of dichloromethane is completed, wash with ethanol and then with deionized water, and finally perform suction filtration and dry in an oven at 65° C. for 12 hours to obtain the microcapsule modifier.

[0045] 200g of straight-run asphalt with a softening point of 46.8°C, 21.2g of Span-80 and 250g of water were emulsified with a high shear machine, and 27.6g of cocoyl 1,3-propylenediamine and 3.6g of 4, The 4-dia...

Embodiment 2

[0047] Dissolve 32.6g of polyethersulfone in dichloromethane, then add a mixture of 148.4g of CYD-128 epoxy resin and 8.5g of benzyl alcohol, stir well to form a dispersed phase; use 1.5% sodium dodecylbenzenesulfonate aqueous solution as Continuous phase, the above-mentioned dispersed phase is added dropwise into the continuous phase, and high-speed stirring is carried out at the same time, and the rotation speed is 2200r / min. After the dropwise addition, react in a constant temperature water bath at 45° C. for 6 hours while stirring at a low speed at 500 r / min. After the complete volatilization reaction of dichloromethane is completed, wash with ethanol and then with deionized water, and finally perform suction filtration and dry in an oven at 60° C. for 15 hours to obtain the microcapsule modifier.

[0048] 200g of oxidized asphalt with a softening point of 63.5°C, 16.8g of polyoxyethylene stearate and 280g of water were shear emulsified with a high shear machine, and 35.5g...

Embodiment 3

[0050] Dissolve 45.5g polysulfone in dichloromethane, then add the mixture of 121.6g E-44 epoxy resin and 5.8g benzyl alcohol, stir well to form a dispersed phase; use 1.0% sodium dodecylbenzenesulfonate aqueous solution as continuous Phase, the above-mentioned dispersed phase was added dropwise into the continuous phase, while stirring at a high speed, the rotation speed was 2000r / min. After the dropwise addition, react in a constant temperature water bath at 35° C. for 7 hours while stirring at a low speed at 650 r / min. After the complete volatilization reaction of dichloromethane is completed, wash with ethanol and then with deionized water, and finally perform suction filtration and dry in an oven at 70° C. for 16 hours to obtain the microcapsule modifier.

[0051] 200g of oxidized pitch with a softening point of 70.2°C, 31.5g of Span-85 and 320g of water were emulsified with a high shear machine, and 38.8g of hexadecyldimethyl tertiary amine and 4.0g of 4,4-bis Continue ...

technical field

[0001] The invention relates to the field of oil drilling plugging, in particular to a plugging agent for drilling fluid and its preparation. Background technique

[0002] In the oil and gas drilling process, lost circulation is a ubiquitous and often encountered complex problem. Downhole accidents caused by lost circulation are extremely harmful to drilling and completion, and have always been an urgent problem to be solved in the field of petroleum engineering. During drilling operations, once lost circulation occurs, it will not only delay time, lose drilling fluid, and damage oil and gas layers, but also may cause well wall instability, leading to a series of complex situations and accidents such as well collapse, pipe sticking, and blowout, and even lead to wellbore failure. scrapped, resulting in significant economic losses.

[0003] Especially in the process of drilling deep oil and gas wells in alpine areas, the number of large fractures and karst-v...

Examples

Embodiment 1

[0044]Dissolve 25g of polysulfone in methylene chloride, then add a mixture of 79g of CYD-128 epoxy resin and 3.8g of benzyl alcohol, stir evenly to form a dispersed phase; use 1.0% sodium dodecylbenzenesulfonate aqueous solution as the continuous phase, The above-mentioned dispersed phase is added dropwise into the continuous phase while stirring at a high speed at a speed of 2600 r / min. After the dropwise addition, react in a constant temperature water bath at 40° C. for 5.5 hours while stirring at a low speed at 600 r / min. After the complete volatilization reaction of dichloromethane is completed, wash with ethanol and then with deionized water, and finally perform suction filtration and dry in an oven at 65° C. for 12 hours to obtain the microcapsule modifier.

[0045] 200g of straight-run asphalt with a softening point of 46.8°C, 21.2g of Span-80 and 250g of water were emulsified with a high shear machine, and 27.6g of cocoyl 1,3-propylenediamine and 3.6g of 4, The 4-dia...

Embodiment 2

[0047] Dissolve 32.6g of polyethersulfone in dichloromethane, then add a mixture of 148.4g of CYD-128 epoxy resin and 8.5g of benzyl alcohol, stir well to form a dispersed phase; use 1.5% sodium dodecylbenzenesulfonate aqueous solution as Continuous phase, the above-mentioned dispersed phase is added dropwise into the continuous phase, and high-speed stirring is carried out at the same time, and the rotation speed is 2200r / min. After the dropwise addition, react in a constant temperature water bath at 45° C. for 6 hours while stirring at a low speed at 500 r / min. After the complete volatilization reaction of dichloromethane is completed, wash with ethanol and then with deionized water, and finally perform suction filtration and dry in an oven at 60° C. for 15 hours to obtain the microcapsule modifier.

[0048] 200g of oxidized asphalt with a softening point of 63.5°C, 16.8g of polyoxyethylene stearate and 280g of water were shear emulsified with a high shear machine, and 35.5g...

Embodiment 3

[0050] Dissolve 45.5g polysulfone in dichloromethane, then add the mixture of 121.6g E-44 epoxy resin and 5.8g benzyl alcohol, stir well to form a dispersed phase; use 1.0% sodium dodecylbenzenesulfonate aqueous solution as continuous Phase, the above-mentioned dispersed phase was added dropwise into the continuous phase, while stirring at a high speed, the rotation speed was 2000r / min. After the dropwise addition, react in a constant temperature water bath at 35° C. for 7 hours while stirring at a low speed at 650 r / min. After the complete volatilization reaction of dichloromethane is completed, wash with ethanol and then with deionized water, and finally perform suction filtration and dry in an oven at 70° C. for 16 hours to obtain the microcapsule modifier.

[0051] 200g of oxidized pitch with a softening point of 70.2°C, 31.5g of Span-85 and 320g of water were emulsified with a high shear machine, and 38.8g of hexadecyldimethyl tertiary amine and 4.0g of 4,4-bis Continue ...