Drilling fluid cooling composite shell phase change microcapsule and preparation method thereof

Abstract

The invention relates to the technical field of drilling fluid cooling, and discloses a drilling fluid cooling composite shell layer phase change microcapsule and a preparation method thereof.The drilling fluid cooling composite shell layer phase change microcapsule comprises a core material and a shell material, the core material comprises a phase change material, a heat conduction material, a stabilizer, a dispersing agent, a coupling agent and a thickening agent, and the shell material comprises an inner shell layer and an outer shell layer; the drilling fluid cooling composite shell phase-change microcapsule has excellent cooling effect and environmental protection performance, when the temperature of the drilling fluid rises, the phase-change material in the microcapsule can absorb heat and generate phase change, so that the temperature of the drilling fluid is reduced, the shell material of the microcapsule can prevent the phase-change material from leaking, the stability and safety of the drilling fluid are ensured, and the drilling fluid cooling composite shell phase-change microcapsule has good application prospects. The microcapsule has the advantages of simple preparation method, low cost, wide application prospect, good cooling effect, excellent environmental protection performance, high stability, good dispersibility and the like, can be widely applied to drilling engineering, improves the drilling efficiency, protects drilling equipment, and has wide application prospect and market potential.

Description

Technical Field

[0001] The present invention relates to the technical field of drilling fluid cooling, and particularly to a composite shell phase change microcapsule for drilling fluid cooling and a preparation method thereof. Background Art

[0002] Drilling is an engineering process that uses mechanical equipment to drill a cylindrical hole with a certain depth in the formation. Cable tool drilling, also known as percussion drilling. The cable tool drill bit is sent to the bottom of the well by a steel wire rope. The walking beam mechanism is driven by power, so that one end of the walking beam moves up and down, and drives the steel wire rope and the drill bit to generate an up and down impact, breaking the rock. The cable tool drilling speed is slow, the efficiency is low, and it cannot adapt to the increasing well depth and complex formations, etc. Drilling is an engineering process that uses mechanical equipment to drill a cylindrical hole with a certain depth in the formation. According to the rock breaking method and the type of tools used, it can be further divided into cable tool drilling and rotary drilling. In geological work, a relatively small-diameter and relatively deep cylindrical round hole drilled underground by drilling equipment. Also known as borehole. The size of the drilling diameter and depth depends on the purpose of drilling and the burial depth of minerals, etc. The drilling diameters for exploring oil, natural gas, and groundwater are all relatively large. The main functions are: obtaining underground physical data, that is, taking core samples, ore samples, cuttings, liquid samples, gas samples, etc. from the drilling. As a geophysical logging channel to obtain various geophysical field data of the rock and ore layers. As an artificial channel to observe the hydrogeological dynamic conditions of the groundwater layer. Used for exploration and production combination, such as drilling for groundwater, oil and gas, geothermal energy, etc. During the drilling process, due to reasons such as formation temperature and drill string friction, the temperature of the drilling fluid will rise, affecting the drilling efficiency and the performance of the drilling fluid. Therefore, cooling the drilling fluid is an important link in the drilling project.

[0003] Traditional methods for cooling drilling fluid mainly include natural cooling, circulating cooling, etc. However, these methods have a slow cooling speed, unsatisfactory effects, and are prone to environmental pollution. The stability and safety of the drilling fluid are poor, resulting in a significant decrease in drilling efficiency, and it is easy to cause high-temperature damage to drilling equipment, causing a large amount of property losses.

[0004] Therefore, we propose a composite shell phase change microcapsule for drilling fluid cooling and a preparation method thereof. Summary of the Invention

[0005] The present invention mainly solves the technical problems existing in the above-mentioned prior art, and provides a composite shell phase change microcapsule for drilling fluid cooling and a preparation method thereof.

[0006] To achieve the above object, the present invention adopts the following technical solution. A composite shell phase change microcapsule for cooling drilling fluid includes a core material and a shell material. The core material includes a phase change material, a heat conductive material, a stabilizer, a dispersant, a coupling agent, and a thickening agent. The shell material includes an inner shell layer and an outer shell layer. The inner shell layer includes a polymer material, a reinforcing agent, and a crosslinking agent. The outer shell layer includes silica, alumina, and inorganic nanoparticles. The phase change material includes paraffin and fatty acid. Paraffin and fatty acid can absorb or release heat when the temperature changes, thereby achieving the cooling of the drilling fluid. The heat conductive material includes graphite and carbon nanotubes. Graphite and carbon nanotubes can enhance the heat conduction performance of the core material and accelerate the heat transfer speed. The stabilizer, dispersant, coupling agent, and thickening agent can improve the stability and dispersibility of the microcapsules, preventing the leakage and agglomeration of the core material.

[0007] Preferably, the polymer material includes polyacrylic acid and polyurethane. Polyacrylic acid and polyurethane have good elasticity and temperature resistance, and can protect the core material from the influence of the external environment.

[0008] Preferably, the reinforcing agent and the crosslinking agent can enhance the mechanical strength and stability of the inner shell layer, preventing it from deforming or cracking in a high-temperature environment.

[0009] Preferably, the silica and alumina have excellent high-temperature resistance and chemical stability, and can further improve the thermal stability and mechanical strength of the microcapsules.

[0010] Preferably, the inorganic nanoparticles can enhance the density and anti-permeability of the outer shell layer, preventing the leakage of the core material.

[0011] A preparation method of the composite shell phase change microcapsule for cooling drilling fluid specifically includes the following steps:

[0012] The first step: Mix the phase change material, the heat conductive material, the stabilizer, the dispersant, the coupling agent, and the thickening agent evenly to prepare the core material;

[0013] The second step: Mix the polymer material, the reinforcing agent, and the crosslinking agent evenly to prepare the inner shell layer material;

[0014] The third step: Coating the inner shell layer material on the surface of the core material to form the inner shell layer;

[0015] The fourth step: Mix the silica, alumina, and inorganic nanoparticles evenly to prepare the outer shell layer material;

[0016] The fifth step: Coating the outer shell layer material on the surface of the inner shell layer to form the outer shell layer, and finally obtaining the composite shell phase change microcapsule for cooling drilling fluid.

[0017] Beneficial effects

[0018] The present invention provides a drilling fluid cooling composite shell phase change microcapsule and a preparation method thereof. It has the following beneficial effects:

[0019] (1) The drilling fluid cooling composite shell phase change microcapsule and the preparation method thereof. The drilling fluid cooling composite shell phase change microcapsule has excellent cooling effect and environmental protection performance. During the drilling process, when the microcapsules are added to the drilling fluid, when the temperature of the drilling fluid rises, the phase change material in the microcapsules will absorb heat and undergo a phase change, thereby reducing the temperature of the drilling fluid. The shell material of the microcapsules can prevent the leakage of the phase change material and ensure the stability and safety of the drilling fluid. The preparation method of the microcapsules is simple and low-cost, has broad application prospects, and has the advantages of good cooling effect, excellent environmental protection performance, high stability, and good dispersibility. It can be widely used in drilling engineering to improve drilling efficiency and protect drilling equipment, and has broad application prospects and market potential.

[0020] (2) The drilling fluid cooling composite shell phase change microcapsule and the preparation method thereof. By setting an outer shell layer, silica and alumina have excellent high-temperature resistance and chemical stability, which can further improve the thermal stability and mechanical strength of the microcapsules. The inorganic nanoparticles can enhance the compactness and anti-permeability of the outer shell layer and prevent the leakage of the core material. Through the ingenious combination and optimization, the effective cooling of the drilling fluid is achieved, providing a strong guarantee for the high efficiency, environmental protection, and safety of drilling engineering.

[0021] (3) The drilling fluid cooling composite shell phase change microcapsule and the preparation method thereof. By setting a core material, the phase change material plays a major role in cooling in the core material, and adjusts the temperature of the drilling fluid by absorbing and releasing heat. The heat-conducting material is used to improve the heat-conducting performance of the phase change material, so that the heat can be transferred and diffused more quickly. The strengthening agent is used to improve the mechanical strength and stability of the microcapsules and prevent the microcapsules from breaking or deforming in the drilling fluid. The stabilizer is used to ensure the stability and lifespan of the microcapsules and prevent the microcapsules from decomposing or failing during use. The dispersant, coupling agent, and thickening agent are used to adjust the dispersibility and fluidity of the microcapsules, so that they can be better mixed and dispersed with the drilling fluid, thereby improving the cooling effect. Specific embodiments

[0022] Example 1: A composite shell phase change microcapsule for cooling drilling fluid, comprising a core material and a shell material. The core material includes a phase change material, a thermal conductive material, a stabilizer, a dispersant, a coupling agent, and a thickening agent. The shell material includes an inner shell layer and an outer shell layer. The inner shell layer includes a polymer material, a reinforcing agent, and a crosslinking agent. The outer shell layer includes silica, alumina, and inorganic nanoparticles. The phase change material includes paraffin and fatty acids, which can absorb or release heat when the temperature changes, thereby achieving the cooling of the drilling fluid. The thermal conductive material includes graphite and carbon nanotubes, which can enhance the thermal conductivity of the core material and accelerate the heat transfer rate. The stabilizer, dispersant, coupling agent, and thickening agent can improve the stability and dispersibility of the microcapsules, preventing the leakage and agglomeration of the core material. The polymer material includes polyacrylic acid and polyurethane, which have good elasticity and temperature resistance, and can protect the core material from the external environment. The reinforcing agent and crosslinking agent can enhance the mechanical strength and stability of the inner shell layer, preventing it from deforming or cracking in a high-temperature environment. Silica and alumina have excellent high-temperature resistance and chemical stability, which can further improve the thermal stability and mechanical strength of the microcapsules. The inorganic nanoparticles can enhance the density and anti-permeability of the outer shell layer, preventing the leakage of the core material. This composite shell phase change microcapsule for cooling drilling fluid has excellent cooling effect and environmental protection performance. During the drilling process, the microcapsules are added to the drilling fluid. When the temperature of the drilling fluid rises, the phase change material in the microcapsules absorbs heat and undergoes a phase change, thereby reducing the temperature of the drilling fluid. The shell material of the microcapsules can prevent the leakage of the phase change material, ensuring the stability and safety of the drilling fluid. The preparation method of this microcapsule is simple and low-cost, with broad application prospects. It has the advantages of good cooling effect, excellent environmental protection performance, high stability, and good dispersibility, and can be widely used in drilling engineering to improve drilling efficiency and protect drilling equipment, with broad application prospects and market potential. By setting the outer shell layer, silica and alumina have excellent high-temperature resistance and chemical stability, which can further improve the thermal stability and mechanical strength of the microcapsules. The inorganic nanoparticles can enhance the density and anti-permeability of the outer shell layer, preventing the leakage of the core material. Through the ingenious combination and optimization, the effective cooling of the drilling fluid is achieved, providing a strong guarantee for the high efficiency, environmental protection, and safety of drilling engineering. By setting the core material, the phase change material plays a major role in cooling the core material, regulating the temperature of the drilling fluid by absorbing and releasing heat. The thermal conductive material is used to improve the thermal conductivity of the phase change material, enabling the heat to be transferred and diffused more quickly. The reinforcing agent is used to improve the mechanical strength and stability of the microcapsules, preventing the microcapsules from cracking or deforming in the drilling fluid. The stabilizer is used to ensure the stability and lifespan of the microcapsules, preventing the microcapsules from decomposing or failing during use. The dispersant, coupling agent, and thickening agent are used to regulate the dispersibility and fluidity of the microcapsules, enabling them to mix and disperse better with the drilling fluid, thereby improving the cooling effect.

[0023] Example 2: On the basis of Example 1, the thermal conductive material includes graphite and carbon nanotubes, which can enhance the thermal conductivity of the core material and accelerate the heat transfer rate. The stabilizer, dispersant, coupling agent, and thickener can improve the stability and dispersibility of the microcapsules, preventing the leakage and agglomeration of the core material. The core material includes a phase change material, a thermal conductive material, a stabilizer, a dispersant, a coupling agent, and a thickener. The shell material includes an inner shell layer and an outer shell layer. The inner shell layer includes a polymer material, a reinforcing agent, and a cross-linking agent. The outer shell layer includes silica, alumina, and inorganic nanoparticles. The phase change material includes paraffin and fatty acids, which can absorb or release heat when the temperature changes, thereby achieving the cooling of the drilling fluid. The polymer material includes polyacrylic acid and polyurethane, which have good elasticity and temperature resistance and can protect the core material from the external environment. The reinforcing agent and the cross-linking agent can enhance the mechanical strength and stability of the inner shell layer, preventing it from deforming or cracking in a high-temperature environment. Silica and alumina have excellent high-temperature resistance and chemical stability, which can further improve the thermal stability and mechanical strength of the microcapsules. The inorganic nanoparticles can enhance the density and anti-permeability of the outer shell layer, preventing the leakage of the core material. By setting the outer shell layer, silica and alumina have excellent high-temperature resistance and chemical stability, which can further improve the thermal stability and mechanical strength of the microcapsules. The inorganic nanoparticles can enhance the density and anti-permeability of the outer shell layer, preventing the leakage of the core material. Through ingenious combination and optimization, the effective cooling of the drilling fluid is achieved, providing a strong guarantee for the high efficiency, environmental protection, and safety of the drilling project. By setting the core material, the phase change material plays a major role in cooling the core material, adjusting the temperature of the drilling fluid by absorbing and releasing heat. The thermal conductive material is used to improve the thermal conductivity of the phase change material, enabling heat to be transferred and diffused more quickly. The reinforcing agent is used to improve the mechanical strength and stability of the microcapsules, preventing the microcapsules from cracking or deforming in the drilling fluid. The stabilizer is used to ensure the stability and lifespan of the microcapsules, preventing the microcapsules from decomposing or failing during use. The dispersant, coupling agent, and thickener are used to adjust the dispersibility and fluidity of the microcapsules, enabling them to mix and disperse better with the drilling fluid, thereby improving the cooling effect. The drilling fluid cooling composite shell layer phase change microcapsules have excellent cooling effects and environmental protection performance. During the drilling process, the microcapsules are added to the drilling fluid. When the temperature of the drilling fluid rises, the phase change material in the microcapsules will absorb heat and undergo a phase change, thereby reducing the temperature of the drilling fluid. The shell material of the microcapsules can prevent the leakage of the phase change material, ensuring the stability and safety of the drilling fluid. The preparation method of the microcapsules is simple and low-cost, with broad application prospects. It has the advantages of good cooling effect, excellent environmental protection performance, high stability, and good dispersibility, and can be widely used in drilling engineering to improve drilling efficiency and protect drilling equipment, with broad application prospects and market potential.

[0024] Example 3: On the basis of Example 1 and Example 2, the polymer material includes polyacrylic acid and polyurethane. Polyacrylic acid and polyurethane have good elasticity and temperature resistance, and can protect the core material from the external environment. The reinforcing agent and cross-linking agent can enhance the mechanical strength and stability of the inner shell layer, preventing it from deforming or cracking in a high-temperature environment. Silicon dioxide and alumina have excellent high-temperature resistance and chemical stability, and can further improve the thermal stability and mechanical strength of the microcapsules. The inorganic nanoparticles can enhance the density and anti-permeability of the outer shell layer, preventing the leakage of the core material. The core material includes a phase change material, a heat-conducting material, a stabilizer, a dispersant, a coupling agent, and a thickening agent. The shell material includes an inner shell layer and an outer shell layer. The inner shell layer includes a polymer material, a reinforcing agent, and a cross-linking agent. The outer shell layer includes silicon dioxide, alumina, and inorganic nanoparticles. The phase change material includes paraffin and fatty acids. Paraffin and fatty acids can absorb or release heat when the temperature changes, thereby achieving the cooling of the drilling fluid. The heat-conducting material includes graphite and carbon nanotubes. Graphite and carbon nanotubes can enhance the heat-conducting performance of the core material and accelerate the heat transfer rate. The stabilizer, dispersant, coupling agent, and thickening agent can improve the stability and dispersibility of the microcapsules, preventing the leakage and agglomeration of the core material. By setting the core material, the phase change material plays a major role in cooling the core material, regulating the temperature of the drilling fluid by absorbing and releasing heat. The heat-conducting material is used to improve the heat-conducting performance of the phase change material, enabling the heat to be transferred and diffused more quickly. The reinforcing agent is used to improve the mechanical strength and stability of the microcapsules, preventing the microcapsules from cracking or deforming in the drilling fluid. The stabilizer is used to ensure the stability and lifespan of the microcapsules, preventing the microcapsules from decomposing or failing during use. The dispersant, coupling agent, and thickening agent are used to regulate the dispersibility and fluidity of the microcapsules, enabling them to mix and disperse better with the drilling fluid, thereby improving the cooling effect. The drilling fluid cooling composite shell layer phase change microcapsules have excellent cooling effects and environmental protection performance. During the drilling process, the microcapsules are added to the drilling fluid. When the temperature of the drilling fluid rises, the phase change material in the microcapsules will absorb heat and undergo a phase change, thereby reducing the temperature of the drilling fluid. The shell material of the microcapsules can prevent the leakage of the phase change material, ensuring the stability and safety of the drilling fluid. The preparation method of the microcapsules is simple and low-cost, has broad application prospects, and has the advantages of good cooling effect, excellent environmental protection performance, high stability, and good dispersibility. It can be widely used in drilling engineering to improve drilling efficiency and protect drilling equipment, and has broad application prospects and market potential.

[0025] A preparation method of a drilling fluid cooling composite shell layer phase change microcapsule specifically includes the following steps:

[0026] The first step: Mix the phase change material, heat-conducting material, stabilizer, dispersant, coupling agent, and thickening agent evenly to prepare the core material;

[0027] Step 2: Mix the polymer material, reinforcing agent, and cross-linking agent evenly to prepare the inner shell layer material;

[0028] Step 3: Coating the inner shell layer material on the surface of the core material to form the inner shell layer;

[0029] Step 4: Mix silicon dioxide, aluminum oxide, and inorganic nanoparticles evenly to prepare the outer shell layer material;

[0030] Step 5: Coating the outer shell layer material on the surface of the inner shell layer to form the outer shell layer, and finally obtaining the composite shell layer phase change microcapsule for cooling drilling fluid.

[0031] Working principle: In practical applications, the prepared composite shell layer phase change microcapsules are added to the drilling fluid. The microcapsules will flow with the circulation of the drilling fluid. When the temperature of the drilling fluid rises, the phase change material in the microcapsules will absorb heat and undergo a phase change, thereby reducing the temperature of the drilling fluid. At the same time, the heat-conducting material can promote the transfer of heat, enabling the heat to be dissipated more quickly and further enhancing the cooling effect. When the temperature of the drilling fluid drops, the phase change material will release heat and return to its original state, thereby maintaining the stability of the drilling fluid. Since the microcapsules have a small particle size and good dispersibility, they will not affect the performance of the drilling fluid.

[0032] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A drilling fluid cooling composite shell phase change microcapsule, characterized in that: The invention comprises a core material and a shell material. The core material comprises a phase change material, a thermal conductive material, a stabilizer, a dispersant, a coupling agent and a thickener. The shell material comprises an inner shell layer and an outer shell layer. The inner shell layer comprises a polymer material, a reinforcing agent and a cross-linking agent. The outer shell layer comprises silicon dioxide, aluminum oxide and inorganic nanoparticles. The phase change material comprises paraffin and fatty acid. Paraffin and fatty acid can absorb or release heat when the temperature changes, so as to cool the drilling fluid. The thermal conductive material comprises graphite and carbon nanotubes. Graphite and carbon nanotubes can enhance the thermal conductivity of the core material and accelerate the heat transfer speed. The stabilizer, dispersant, coupling agent and thickener can improve the stability and dispersibility of the microcapsules and prevent the leakage and agglomeration of the core material.

2. The drilling fluid cooling composite shell phase change microcapsule according to claim 1, characterized in that: The polymer material includes polyacrylic acid and polyurethane. Polyacrylic acid and polyurethane have good elasticity and temperature resistance and can protect the core material from being affected by the external environment.

3. The drilling fluid cooling composite shell phase change microcapsule according to claim 1, characterized in that: The reinforcing agent and the cross-linking agent can enhance the mechanical strength and stability of the inner shell layer, and prevent it from deforming or breaking in a high temperature environment.

4. The drilling fluid cooling composite shell phase change microcapsule according to claim 1, characterized in that: The silicon dioxide and aluminum oxide have excellent high temperature resistance and chemical stability, and can further improve the thermal stability and mechanical strength of the microcapsules.

5. The drilling fluid cooling composite shell phase change microcapsule according to claim 1, characterized in that: The inorganic nanoparticles can enhance the compactness and anti-permeability performance of the outer shell layer and prevent the core material from leaking.

6. A method for preparing drilling fluid cooling composite shell phase change microcapsules, characterized in that: The specific steps include: The first step: uniformly mixing the phase change material, the thermal conductive material, the stabilizer, the dispersant, the coupling agent and the thickener to prepare the core material; Step 2: Evenly mix the polymer material, the reinforcing agent and the cross-linking agent to prepare the inner shell material; Step 3: Cover the inner shell material on the surface of the core material to form an inner shell layer; Step 4: Evenly mix silicon dioxide, aluminum oxide and inorganic nanoparticles to prepare a shell layer material; The fifth step is to coat the outer shell material on the surface of the inner shell to form an outer shell layer, and finally obtain the drilling fluid cooling composite shell phase change microcapsule.