An ultra-high density oil-based drilling fluid

An oil-based drilling fluid and ultra-high-density technology, applied in drilling compositions, chemical instruments and methods, etc., can solve problems that are difficult to adapt to long-term drilling, well completion requirements, and drilling displacement that cannot meet the requirements of purifying wellbore , rheology and suspension ability are difficult to coordinate and other problems, to achieve good emulsion stability, expand the range of density use, and low preparation costs.

An oil-based drilling fluid and ultra-high-density technology, applied in drilling compositions, chemical instruments and methods, etc., can solve problems that are difficult to adapt to long-term drilling, well completion requirements, and drilling displacement that cannot meet the requirements of purifying wellbore , rheology and suspension ability are difficult to coordinate and other problems, to achieve good emulsion stability, expand the range of density use, and low preparation costs.

CN105623628BActive Publication Date: 2021-04-02成都西油华巍科技有限公司 +1

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • An ultra-high density oil-based drilling fluid
  • An ultra-high density oil-based drilling fluid
  • An ultra-high density oil-based drilling fluid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0049] Embodiment 1: a kind of density is 2.80g / cm3, and oil-water ratio is the ultra-high density oil-based drilling fluid of 95:5. It is prepared from the following raw materials in weight percentage, base oil: 285.0ml; emulsifier: 6.0g; wetting agent: 4.8g; viscosifier: 6.0g; fluid loss reducer: 12.0g; g; alkalinity regulator: 6.0g; calcium chloride aqueous solution with a mass concentration of 20%: 15.0ml; weighting agent: 1382.0g.

[0050] Its preparation method comprises the following steps:

[0051]a. Add the base oil into the high mixing cup, then add the emulsifier and wetting agent, and stir at a high speed of 12000r / min for 10min to make the system evenly mixed;

[0052] b. Under the condition of maintaining stirring, add the alkalinity regulator and calcium chloride brine into the high stirring cup, and stir at a high speed of 12000r / min for 10min, so that the added components are mixed and stirred evenly;

[0053] c. Under the condition of maintaining stirring, ...

Embodiment 2

[0057] Embodiment 2: a kind of density is 2.50g / cm3, and oil-water ratio is the ultra-high density oil-based drilling fluid of 9:1. It is prepared from the following raw materials by weight percentage, base oil: 270ml; emulsifier: 6.0g; wetting agent: 4.8g; viscosifier: 7.2g; fluid loss reducer: 12.0g; shearing agent: 0.5g Alkalinity regulator: 6.0g; Calcium chloride aqueous solution with a mass concentration of 20%: 30.0ml; Weighting agent: 1125.0g.

[0058] Its preparation method is the same as the preparation method described in Example 1.

Embodiment 3

[0059] Embodiment 3: a kind of density is 2.00g / cm3, and oil-water ratio is the ultra-high density oil-based drilling fluid of 9:1. It is prepared from the following raw materials by weight percentage, base oil: 270ml; emulsifier: 7.2g; wetting agent: 4.2g; viscosifier: 5.1g; fluid loss reducer: 12.0g; alkalinity regulator: 9.0 g; calcium chloride aqueous solution with a mass concentration of 30%: 30.0ml; plugging agent: 6.0g; weighting agent: 600.0g.

[0060] Its preparation method comprises the following steps:

[0061] a. Add the base oil into the high mixing cup, then add the emulsifier and wetting agent, and stir at a high speed of 12000r / min for 10min to make the system evenly mixed;

[0062] b. While stirring at a high speed, add the alkalinity regulator and calcium chloride brine into the high stirring cup, and stir at a high speed of 12000r / min for 10 minutes, so that the added components are mixed and stirred evenly;

[0063] c. Add viscosifier, fluid loss reducer,...

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
densityaaaaaaaaaa
densityaaaaaaaaaa
densityaaaaaaaaaa
Login to View More

Abstract

The present invention discloses an ultra-high density oil-based drilling fluid and a preparation method thereof. Oil-based drilling fluids in the prior art have the problems of poor emulsion stability and rheology, and easily lead to well wall chipping and collapsing, and blocking, long drilling cycle and other complex situations can be caused. The ultra-high density oil-based drilling fluid has a density of 0.93g / cm<3> to 2.80g / cm<3>, and comprises base oil, an emulsifier, a wetting agent, a tackifier, a filtrate loss reducer, a shear strength improving agent, an alkalinity adjusting agent, an aqueous solution of calcium chloride, a blocking agent, a weighting agent and the like, a formula and the preparation method of the ultra-high density oil-based drilling fluid are improved. The ultra-high density oil-based drilling fluid has good emulsifying stability and rheology, as well as mud shale strong inhibition, has the characteristics of small dosages of a variety of treatment agents, low preparation cost, high emulsion-breaking voltage, good rheology, low fluid loss, resistance to water, soil and salt and water-based drilling fluid and strong cement paste pollution performance and the like, and can be used in special drilling work in ultra-high pressure oil and gas wells, shale gas wells and strong water sensitive formation extended reach wells, horizontal wells and the like.

Description

technical field [0001] The invention relates to the technical field of oil-based drilling fluid for oil, natural gas and shale gas drilling engineering, in particular to an ultra-high-density oil-based drilling fluid and a preparation method thereof. Background technique [0002] At present, China's onshore and offshore oil and gas drilling and production are extending to deep layers (under 4500m underground), ultra-deep layers (under 6000m underground) and shale gas fields, such as Sichuan, Xinjiang, South China Sea and other oil regions. During the drilling process, high pressure (higher than 70MPa) and high water sensitivity and easy-to-collapse mud shale technical problems are faced. [0003] When drilling horizontal wells in the above formations to develop oil and gas, oil-based drilling fluids are required. Compared with water-based drilling fluid, oil-based drilling fluid has many advantages such as high temperature resistance, salt resistance, calcium intrusion resi...

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
02 Apr 2021
Publication
CN105623628B
IPC
C09K8/32
Inventors
宋芳; 徐兴华