Method of utilizing nanometer silicon dioxide to improve properties of water-based drilling fluid at different temperatures

Abstract

The invention provides a method of utilizing nanometer silicon dioxide to improve properties of water-based drilling fluid at different temperatures. The method comprises a step of adding a nanometer silicon dioxide dispersing agent into base mud, wherein the mass of the nanometer silicon dioxide particle in the nanometer silicon dioxide dispersing agent is 5-10% of total mass of the base mud and the nanometer silicon dioxide dispersing agent. Due to the nano-scale particle size, the nanometer silicon dioxide material can be filled into small holes and cracks of the shale stratum to improve the plugging effect of the water-based drilling fluid, slow down the trend of permeation of the drilling fluid to the stratum and expansion and chipping of the stratum after water absorption, and improve the stability of the borehole wall. The nanometer silicon dioxide can strengthen the stability of fresh-water base mud and bentonite base mud by increasing the negative charge level of the system. The nanometer silicon dioxide also can enable the base mud to form thinner and compact mud cakes and facilitate the de-filtration effect to be obvious.

Description

technical field

[0001] The invention belongs to the field of oil and gas drilling, and in particular relates to a method for improving the performance of water-based drilling fluid at different temperatures by using nano silicon dioxide. Background technique

[0002] The main reason for wellbore instability in shale formations during oil and gas drilling is that shale swells and blocks after absorbing water. Wellbore instability costs the world oil industry a conservative estimate of $500 million per year.

[0003] However, after the fluid in the drilling fluid invades the shale, the pressure of the liquid column formed by the drilling fluid will be transmitted to the pores of the shale, which will weaken the supporting effect of the drilling fluid on the well wall, causing the shale to be damaged and the well wall to be damaged. Unsteady. It is generally believed that the oil-based drilling fluid with balanced activity can solve the problem of wellbore instability in shal...

Examples

Embodiment 1

[0057] This embodiment provides a method of using nano-silica to improve the performance of water-based drilling fluid. Nano-silica is added in the base slurry in the form of dispersion liquid, and the mass of nano-silica particles accounts for the 5% of the total mass of the nano-silica dispersion.

[0058] The base pulp used in this example is fresh water mud (FWM for short), and its formula and basic performance parameters are shown in Table 1.

[0059] Table 1 Formula and basic properties of freshwater base pulp (FWM)

[0060]

[0061] The basic performance parameters of the nano-silica dispersion liquid NP-A (abbreviated as NP-A) used in this example are shown in Table 2.

[0062] Table 2 Basic performance parameters of nano-silica dispersion NP-A

[0063] code name Exterior Density / g·cm -3 Average particle size / nm Concentration / % pH NP-A Transparent liquid 1.21 10～20 30 9-11

[0064] Using CM12 / STEM transmission electron microsco...

Embodiment 2

[0080] Present embodiment is roughly the same as embodiment 1, and nano-silica adds among the base slurry with the form of dispersion liquid,

[0081] The difference is that the nano-silica dispersion NP-B (abbreviated as NP-B) used in this example is different from Example 1, and its basic performance parameters are shown in Table 4.

[0082]

[0083] Table 4 Basic performance parameters of nano-silica dispersion NP-B

[0084] code name Exterior Density / g·cm -3 Average particle size / nm Concentration / % pH NP-B milky white liquid 1.20 10～20 30 9

[0085] Using CM12 / STEM transmission electron microscope to observe the morphology of nano-silica particles in nano-silica dispersion NP-B, the results are as follows Figure 6 shown.

[0086] Utilize the same method as Example 1 to carry out the test of main performance parameters (Zeta potential, average particle size, plastic viscosity of base slurry, dynamic shear force and fluid loss) to the ...

Embodiment 3

[0090] This example is roughly the same as Example 1, except that the base slurry selected in this example is bentonite mud (abbreviated as BM), and its formula and basic performance parameters are shown in Table 6.

[0091] Table 6 Bentonite base slurry (BM) formula and basic performance parameters

[0092] water / g Sodium bentonite / g Density / g·cm -3 Plastic viscosity / mPa·s Dynamic shear force / Pa Filtration / ml pH 350 30 1.04 9 15 15.5 9

[0093] Utilize the same method as Example 1 to carry out the test of main performance parameters (Zeta potential, average particle size, plastic viscosity of base slurry, dynamic shear force and fluid loss) to the bentonite base slurry after adding nano-silica NP-A, Test results such as Figure 11 , Table 7, Figure 12 to Figure 14 shown. It can be seen from Table 7 that the addition of nano-silica NP-A with a mass concentration of 5% can reduce the average particle size of bentonite base slurry.

[00...

technical field

[0001] The invention belongs to the field of oil and gas drilling, and in particular relates to a method for improving the performance of water-based drilling fluid at different temperatures by using nano silicon dioxide. Background technique

[0002] The main reason for wellbore instability in shale formations during oil and gas drilling is that shale swells and blocks after absorbing water. Wellbore instability costs the world oil industry a conservative estimate of $500 million per year.

[0003] However, after the fluid in the drilling fluid invades the shale, the pressure of the liquid column formed by the drilling fluid will be transmitted to the pores of the shale, which will weaken the supporting effect of the drilling fluid on the well wall, causing the shale to be damaged and the well wall to be damaged. Unsteady. It is generally believed that the oil-based drilling fluid with balanced activity can solve the problem of wellbore instability in shal...

Examples

Embodiment 1

[0057] This embodiment provides a method of using nano-silica to improve the performance of water-based drilling fluid. Nano-silica is added in the base slurry in the form of dispersion liquid, and the mass of nano-silica particles accounts for the 5% of the total mass of the nano-silica dispersion.

[0058] The base pulp used in this example is fresh water mud (FWM for short), and its formula and basic performance parameters are shown in Table 1.

[0059] Table 1 Formula and basic properties of freshwater base pulp (FWM)

[0060]

[0061] The basic performance parameters of the nano-silica dispersion liquid NP-A (abbreviated as NP-A) used in this example are shown in Table 2.

[0062] Table 2 Basic performance parameters of nano-silica dispersion NP-A

[0063] code name Exterior Density / g·cm -3 Average particle size / nm Concentration / % pH NP-A Transparent liquid 1.21 10～20 30 9-11

[0064] Using CM12 / STEM transmission electron microsco...

Embodiment 2

[0080] Present embodiment is roughly the same as embodiment 1, and nano-silica adds among the base slurry with the form of dispersion liquid,

[0081] The difference is that the nano-silica dispersion NP-B (abbreviated as NP-B) used in this example is different from Example 1, and its basic performance parameters are shown in Table 4.

[0082]

[0083] Table 4 Basic performance parameters of nano-silica dispersion NP-B

[0084] code name Exterior Density / g·cm -3 Average particle size / nm Concentration / % pH NP-B milky white liquid 1.20 10～20 30 9

[0085] Using CM12 / STEM transmission electron microscope to observe the morphology of nano-silica particles in nano-silica dispersion NP-B, the results are as follows Figure 6 shown.

[0086] Utilize the same method as Example 1 to carry out the test of main performance parameters (Zeta potential, average particle size, plastic viscosity of base slurry, dynamic shear force and fluid loss) to the ...

Embodiment 3

[0090] This example is roughly the same as Example 1, except that the base slurry selected in this example is bentonite mud (abbreviated as BM), and its formula and basic performance parameters are shown in Table 6.

[0091] Table 6 Bentonite base slurry (BM) formula and basic performance parameters

[0092] water / g Sodium bentonite / g Density / g·cm -3 Plastic viscosity / mPa·s Dynamic shear force / Pa Filtration / ml pH 350 30 1.04 9 15 15.5 9

[0093] Utilize the same method as Example 1 to carry out the test of main performance parameters (Zeta potential, average particle size, plastic viscosity of base slurry, dynamic shear force and fluid loss) to the bentonite base slurry after adding nano-silica NP-A, Test results such as Figure 11 , Table 7, Figure 12 to Figure 14 shown. It can be seen from Table 7 that the addition of nano-silica NP-A with a mass concentration of 5% can reduce the average particle size of bentonite base slurry.

[00...

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