Temporary plugging agent for fracturing and preparation method thereof

Abstract

The invention belongs to the technical field of oilfield production, and in particular relates to a temporary plugging agent for fracturing and a preparation method thereof. The components and parts by weight are: 38 parts of hydroxypropyl cellulose and 15 parts of polyvinyl butyral , 16.5 parts of zinc oxide, 27 parts of urea-formaldehyde resin, 6 parts of hexamethylene tetraammonium, 14 parts of calcium hypochlorite. Mix hydroxypropyl cellulose, polyvinyl butyral, zinc oxide, urea-formaldehyde resin, hexamethylenetetraammonium and calcium hypochlorite at room temperature at 25°C, and then add the mixture slowly under stirring After stirring in water for 30 minutes, the temporary plugging agent for fracturing can be obtained. This temporary plugging agent can withstand a pressure difference of 40.6MPa after waiting for 2 hours in the wellbore at 60°C. After the gel is broken, the viscosity of the gel-breaking fluid is less than 5mPa·S, and all of it can be discharged to the ground through the flowback process.

Description

Technical field:

[0001] The invention belongs to the technical field of oilfield production, and in particular relates to a temporary plugging agent for fracturing and a preparation method thereof. Background technique:

[0002] With the continuous development of oil and gas resources in my country, the geological conditions of reservoirs are becoming more and more complex, and the difficulty of exploitation is also increasing. In recent years, for reservoirs with strong heterogeneity, low permeability, and ultra-low permeability, in order to further improve the stimulation efficiency and achieve uniform stimulation, the temporary plugging and diversion technology has been proposed, which is to add temporary plugging and diversion in real time during the hydraulic fracturing process. It can temporarily plug the artificial fractures that have been formed, force the fractures to crack and expand in other directions, and open new fractures under high pressure to increase the co...

Examples

Embodiment 1

[0014] A temporary plugging agent for fracturing, its components and parts by weight are: 35 parts of hydroxypropyl cellulose, 10 parts of polyvinyl butyral, 15 parts of zinc oxide, 20 parts of urea-formaldehyde resin, hexamethylene 3 parts of base tetraammonium, 10 parts of calcium hypochlorite.

[0015] The preparation method of temporary plugging agent for fracturing is as follows: at room temperature 25°C, 35kg of hydroxypropyl cellulose, 10kg of polyvinyl butyral, 15kg of zinc oxide, 20kg of urea-formaldehyde resin, hexamethylene tetraammonium 3kg and 10kg of calcium hypochlorite are mixed evenly, and then the mixture is slowly added to 527kg of water under stirring conditions, and after stirring for 30 minutes, the temporary plugging agent for fracturing can be obtained. This temporary plugging agent can withstand a pressure difference of 45.3MPa after waiting for 4 hours in the wellbore at 45°C. After the gel is broken, the viscosity of the gel-breaking fluid is less th...

Embodiment 2

[0017] A temporary plugging agent for fracturing, its components and parts by weight are: 38 parts of hydroxypropyl cellulose, 15 parts of polyvinyl butyral, 16.5 parts of zinc oxide, 27 parts of urea-formaldehyde resin, hexamethylene 6 parts of base tetraammonium, 14 parts of calcium hypochlorite.

[0018] The preparation method of temporary plugging agent for fracturing is as follows: 38kg of hydroxypropyl cellulose, 15kg of polyvinyl butyral, 16.5kg of zinc oxide, 27kg of urea-formaldehyde resin, hexamethylene tetraammonium 6kg and 14kg of calcium hypochlorite are mixed evenly, and then the mixture is slowly added to 497kg of water under stirring conditions, and after stirring for 30 minutes, the temporary plugging agent for fracturing can be obtained. This temporary plugging agent can withstand a pressure difference of 40.6MPa after waiting for 2 hours in the wellbore at 60°C. After the gel is broken, the viscosity of the gel-breaking fluid is less than 5mPa·S, and it can ...

Embodiment 3

[0020] A temporary plugging agent for fracturing, its components and parts by weight are: 40 parts of hydroxypropyl cellulose, 20 parts of polyvinyl butyral, 18 parts of zinc oxide, 33 parts of urea-formaldehyde resin, hexamethylene 8 parts of base tetraammonium, 18 parts of calcium hypochlorite.

[0021] The preparation method of temporary plugging agent for fracturing is as follows: 40kg of hydroxypropyl cellulose, 20kg of polyvinyl butyral, 18kg of zinc oxide, 33kg of urea-formaldehyde resin, and 8kg of hexamethylene tetraammonium are mixed at room temperature at 25°C. Mix evenly with 18kg of calcium hypochlorite, then slowly add the mixture into 459kg of water under stirring conditions, and stir for 30 minutes to obtain a temporary plugging agent for fracturing. This temporary plugging agent can withstand a pressure difference of 31.9MPa after waiting for 4 hours in the wellbore at 90°C. After the gel is broken, the viscosity of the gel-breaking fluid is less than 5mPa·S, ...

Technical field:

[0001] The invention belongs to the technical field of oilfield production, and in particular relates to a temporary plugging agent for fracturing and a preparation method thereof. Background technique:

[0002] With the continuous development of oil and gas resources in my country, the geological conditions of reservoirs are becoming more and more complex, and the difficulty of exploitation is also increasing. In recent years, for reservoirs with strong heterogeneity, low permeability, and ultra-low permeability, in order to further improve the stimulation efficiency and achieve uniform stimulation, the temporary plugging and diversion technology has been proposed, which is to add temporary plugging and diversion in real time during the hydraulic fracturing process. It can temporarily plug the artificial fractures that have been formed, force the fractures to crack and expand in other directions, and open new fractures under high pressure to increase the co...

Examples

Embodiment 1

[0014] A temporary plugging agent for fracturing, its components and parts by weight are: 35 parts of hydroxypropyl cellulose, 10 parts of polyvinyl butyral, 15 parts of zinc oxide, 20 parts of urea-formaldehyde resin, hexamethylene 3 parts of base tetraammonium, 10 parts of calcium hypochlorite.

[0015] The preparation method of temporary plugging agent for fracturing is as follows: at room temperature 25°C, 35kg of hydroxypropyl cellulose, 10kg of polyvinyl butyral, 15kg of zinc oxide, 20kg of urea-formaldehyde resin, hexamethylene tetraammonium 3kg and 10kg of calcium hypochlorite are mixed evenly, and then the mixture is slowly added to 527kg of water under stirring conditions, and after stirring for 30 minutes, the temporary plugging agent for fracturing can be obtained. This temporary plugging agent can withstand a pressure difference of 45.3MPa after waiting for 4 hours in the wellbore at 45°C. After the gel is broken, the viscosity of the gel-breaking fluid is less th...

Embodiment 2

[0017] A temporary plugging agent for fracturing, its components and parts by weight are: 38 parts of hydroxypropyl cellulose, 15 parts of polyvinyl butyral, 16.5 parts of zinc oxide, 27 parts of urea-formaldehyde resin, hexamethylene 6 parts of base tetraammonium, 14 parts of calcium hypochlorite.

[0018] The preparation method of temporary plugging agent for fracturing is as follows: 38kg of hydroxypropyl cellulose, 15kg of polyvinyl butyral, 16.5kg of zinc oxide, 27kg of urea-formaldehyde resin, hexamethylene tetraammonium 6kg and 14kg of calcium hypochlorite are mixed evenly, and then the mixture is slowly added to 497kg of water under stirring conditions, and after stirring for 30 minutes, the temporary plugging agent for fracturing can be obtained. This temporary plugging agent can withstand a pressure difference of 40.6MPa after waiting for 2 hours in the wellbore at 60°C. After the gel is broken, the viscosity of the gel-breaking fluid is less than 5mPa·S, and it can ...

Embodiment 3

[0020] A temporary plugging agent for fracturing, its components and parts by weight are: 40 parts of hydroxypropyl cellulose, 20 parts of polyvinyl butyral, 18 parts of zinc oxide, 33 parts of urea-formaldehyde resin, hexamethylene 8 parts of base tetraammonium, 18 parts of calcium hypochlorite.

[0021] The preparation method of temporary plugging agent for fracturing is as follows: 40kg of hydroxypropyl cellulose, 20kg of polyvinyl butyral, 18kg of zinc oxide, 33kg of urea-formaldehyde resin, and 8kg of hexamethylene tetraammonium are mixed at room temperature at 25°C. Mix evenly with 18kg of calcium hypochlorite, then slowly add the mixture into 459kg of water under stirring conditions, and stir for 30 minutes to obtain a temporary plugging agent for fracturing. This temporary plugging agent can withstand a pressure difference of 31.9MPa after waiting for 4 hours in the wellbore at 90°C. After the gel is broken, the viscosity of the gel-breaking fluid is less than 5mPa·S, ...