Sulfonated asphalt for water-based mud resistant to high temperature and high pressure and preparation method

Abstract

The invention discloses sulfonated asphalt for high-temperature and high-pressure resistant water-based mud and a preparation method, and mainly relates to the technical field of drilling fluids. Raw materials and a sulfonating agent are respectively mixed with a solvent, then sulfonation reaction is carried out, then neutralization and drying are carried out by an alkaline aqueous solution, a powdery product is obtained, the raw materials comprise any one or a combination of more of heavy oil, modified heavy oil, asphalt, modified asphalt, coal pitch, natural asphalt, plant asphalt and SEBS, the solvent is a mixture of one or more of C1-5 carbon atoms, C1-6 carbon atoms, C1-6 carbon atoms, C1-6 carbon atoms, C1-6 carbon atoms and C1-6 carbon atoms, and the sulfonating agent is a mixture of C1-6 carbon atoms, C1-6 carbon atoms and C1-6 carbon atoms. And chlorine or bromine substitutes 1-3 hydrogen atoms in an alkane structure. The method has the beneficial effects that the reaction can be carried out at low temperature, so that the reaction is mild and controllable, and the product quality is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of drilling fluid, in particular to sulfonated asphalt for high-temperature and high-pressure resistant water-based mud and a preparation method thereof. Background Art

[0002] During the drilling process, the problem of instability of the wellbore wall is often encountered, which leads to a series of complex situations in the wellbore, and even causes engineering accidents, which seriously hinders the progress of the project and affects the economic benefits. Sulfonated asphalt is a treatment agent with good plugging properties and is widely used in drilling fluids. It has a significant stabilizing effect on broken rock formations. The water-soluble components of sulfonated asphalt are macromolecules with negative ions. After entering the mud, it adsorbs on the edge of the positively charged soil to prevent the dispersion of shale particles; adsorbing on the micro cracks of the shale on the wellbore wall can prevent water from penetrating into the shale to reduce the erosion of blocks. The water-insoluble components of sulfonated asphalt can provide particles of appropriate size to help build the wall and improve the quality of the mud; covering the rock surface can inhibit the dispersion of shale. Therefore, the mud cake treated with sulfonated asphalt becomes thinner and the compressibility increases, so the water loss decreases. At the same time, it can increase the lubricity of the mud cake, reduce the drag and torque of the drill tool, extend the service life of the drill bit, and have the effect of preventing and releasing the jam. It can maintain low shear force and low water loss at high temperatures. It can be seen that sulfonated asphalt has significant functions of anti-collapse, high temperature resistance and lubrication. However, the performance of sulfonated asphalt is restricted by the asphalt raw material.

[0003] The structure of asphalt is very complex, and the sulfonation of its components is a very complex chemical process. From the structural analysis of the known components of asphalt, the carbon chains and carbon rings in alkanes, cycloalkanes, aromatics, condensed aromatics, and heterocyclic hydrocarbons in the asphalt components, as well as the hydrogen atoms on the heterocyclic rings can be replaced by sulfonic groups to generate various asphalt sulfonates with unfixed components. However, due to the huge asphalt molecules and stable structure, sulfonation is relatively difficult. In the previous process, appropriate initiators are often added to the reaction to increase the efficiency of the sulfonation reaction. However, since solvents such as white oil and diesel are often used as solvents, the asphalt is not fully dissolved, and high temperatures are required to increase energy consumption. In addition, the raw materials are not dispersed thoroughly, which affects the sulfonation efficiency. When using high-carbon chain oil solvents, the sulfonating agent often uses fuming sulfuric acid, which produces a large amount of salt, affects the product quality, and the waste acid treatment remaining after the reaction increases a large amount of production costs and environmental protection costs. Summary of the invention

[0004] The purpose of the present invention is to provide a sulfonated asphalt for water-based mud resistant to high temperature and high pressure and a preparation method thereof, which can react at low temperature, making the reaction mild and controllable, thereby greatly improving the product quality.

[0005] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0006] A sulfonated asphalt for water-based mud resistant to high temperature and high pressure, the raw materials of which include any one or a combination of heavy oil, modified heavy oil, asphalt, modified asphalt, coal tar, natural asphalt, plant asphalt, SEBS, and before the sulfonation process, the raw materials and the sulfonating agent are respectively mixed with a solvent, and the solvent is a normal or isomeric alkane with a total carbon atom number of 1-5, obtained by replacing 1-3 hydrogen atoms.

[0007] Before the sulfonation process, the mass ratio of the raw material to the solvent is 1%-50%, the sulfonating agent is sulfur trioxide, and the mass ratio of sulfur trioxide to the solvent is 1%-30%.

[0008] The sulfonation reaction is carried out at a temperature of 10-60°C.

[0009] The following preparation method is adopted: the raw material and the sulfonating agent are mixed with the solvent respectively and then subjected to sulfonation reaction, and then neutralized with an alkaline aqueous solution after the reaction, and passed into a dryer for drying to obtain a powdery product.

[0010] The alkaline aqueous solution is an aqueous solution of any concentration of any one of sodium hydroxide, potassium hydroxide and ammonia.

[0011] The temperature of the neutralization reaction is maintained at 10-60°C.

[0012] A method for preparing sulfonated asphalt for water-based mud resistant to high temperature and high pressure, comprising: mixing raw materials and a sulfonating agent with a solvent respectively, and then subjecting the mixture to a sulfonation reaction, and then neutralizing the mixture with an alkaline aqueous solution, and drying the mixture to obtain a powdered product, wherein the raw materials include any one or a combination of heavy oil, modified heavy oil, asphalt, modified asphalt, coal tar, natural asphalt, vegetable asphalt, and SEBS, and the solvent is a normal or isomeric alkane having a total carbon atom count of 1 to 5, obtained by replacing 1 to 3 hydrogen atoms.

[0013] The temperature of the sulfonation reaction is 10-60° C., the temperature of the neutralization reaction is 10-60° C., and the neutralization reaction is performed using an aqueous solution of any concentration including sodium hydroxide, potassium hydroxide, and ammonia.

[0014] The mass ratio of the raw material to the solvent is 1%-50%, the sulfonating agent is sulfur trioxide, and the mass ratio of sulfur trioxide to the solvent is 1%-30%.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] This method uses low-carbon chain halogenated hydrocarbons to innovatively dissolve sulfur trioxide directly in the solvent. It solves the problem of incomplete and insufficient dissolution of raw materials, greatly improves product quality, and greatly increases the degree of sulfonation of raw materials. Compared with similar domestic products, the sodium sulfonate base content is increased by more than 100%. At the same time, it solves the problem of sulfur trioxide being in a solid state at room temperature to low temperature, and can react at low temperature, making the reaction mild and controllable, greatly improving product quality. In addition, low-carbon chain halogenated hydrocarbons, as excellent solvents, can dissolve various additives and modify the raw materials before sulfonation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a picture of the filter cake obtained through the HTHP high temperature and high pressure filtration loss test. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the application equally.

[0019] The instruments, reagents, materials, etc. involved in the following embodiments, unless otherwise specified, are all conventional instruments, reagents, materials, etc. in the prior art and can be obtained through regular commercial channels. The experimental methods, detection methods, etc. involved in the following embodiments, unless otherwise specified, are all conventional experimental methods, detection methods, etc. in the prior art.

[0020] Embodiment 1:

[0021] In a 1000ml three-necked flask, add 200g solvent ethylene dichloride and 100g road asphalt, in a dropping funnel, add 160g ethylene dichloride and 40g sulfur trioxide, and slowly add sulfonating agent to the three-necked flask, cool it in a water bath, and control the addition speed to keep the reaction temperature at about 25°C. After the addition is completed, immediately add 200g of 20% sodium hydroxide solution to the bottle. After neutralization, pour it into a twin-screw rotary evaporator, pass heat transfer oil, and evaporate to dryness. After drying, take out the sample, crush it and bag it, and name it HM55.

[0022] Embodiment 2:

[0023] In a 1000ml three-necked flask, add 200g solvent ethylene dichloride and 30g road asphalt, 30g coal tar, 30g natural asphalt, 10g asphalt glue, and in a dropping funnel, add 160g ethylene dichloride and 40g sulfur trioxide. Slowly add sulfonating agent to the three-necked flask, cool it in a water bath, and control the addition speed to keep the reaction temperature at about 25°C. After the addition is completed, immediately add 200g of 20% sodium hydroxide solution to the bottle. After neutralization, pour it into a twin-screw rotary evaporator, pass heat transfer oil, and evaporate to dryness. After drying, take out the sample, crush it and bag it, and name it HM56.

[0024] The above samples were analyzed and tested according to the enterprise standard of China Petrochemical Corporation "Q / SHCG0003.1-2023 Technical Requirements for Asphalt Treatment Agents for Drilling Fluids Part 1: Sulfonated Asphalt"

[0025] project HM55 HM56 SOLTEX A domestic product pH 8 8 8 9 Loss on baking, % 2.24 2.47% 6.40 5.02 Dimethyl sulfoxide dissolved matter, % 67.33 81.33% 72.87 46.61 Sodium sulfonate content, % 16.28 19.81% 16.93 4.62 Water soluble matter, % 75.22 75.55% 80.92 87.88 Oil soluble matter, % 25.4 34.61% 24.9 28.98 High temperature and high pressure filtration reduction rate, % 56.06 60.74 49.54 50.46

[0026] Table 1 Comparison of patented products and mainstream products at home and abroad

[0027] It is not difficult to see from the experimental data that HM55 in Example 1 has a lower sodium sulfonate content than HM56 synthesized in Example 2, that is, a lower degree of sulfonation. It shows that different raw materials have significantly different results for similar reaction conditions, which is caused by the complex molecular structure and variable composition of asphalt raw materials. The main performance indicators of HM55 and HM56 products in these two examples meet the standard requirements. At the same time, the key indicators of dimethyl sulfoxide dissolved matter and sodium sulfonate content indicating the depth of sulfonation are significantly ahead of domestic products. This is because most of the products currently on sale in China are sulfur trioxide gas phase sulfonation: that is, gaseous sulfur trioxide is passed into asphalt dissolved in solvent oil (such as white oil), the reaction time is very long and not sufficient, and the degree of sulfonation is low. A large amount of other products need to be added to adjust the performance, resulting in abnormally low content of dimethyl sulfoxide dissolved matter and sodium sulfonate groups. Compared with advanced foreign products, this embodiment is already leading in the key indicators of sulfonation depth and filtration loss reduction, and other indicators are close to or slightly lower.

[0028] The filter cake obtained by HTHP high temperature and high pressure filtration loss test is as follows Figure 1 As shown in the figure, although the filter cake of HM56 is less uniform than that of foreign products, it is denser and thinner. That is, the mud cake is formed faster and has better toughness. It is not easy to fall off or collapse when used underground, and it is more effective in preventing shale hydration.

[0029] In fact, the final performance of sulfonated asphalt is greatly affected by the properties of the asphalt raw materials. This description only shows two types of data indicators with more prominent ones.

Claims

1. A sulfonated asphalt for water-based mud resistant to high temperature and high pressure, characterized in that: The raw materials include any one or a combination of heavy oil, modified heavy oil, asphalt, modified asphalt, coal tar, natural asphalt, vegetable asphalt, SEBS, and before the sulfonation process, the raw materials and the sulfonating agent are mixed with a solvent respectively, and the solvent is a normal or isomeric alkane with a total carbon atom number of 1-5, obtained by replacing 1-3 hydrogen atoms.

2. The sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 1, characterized in that: Before the sulfonation process, the mass ratio of the raw material to the solvent is 1%-50%, the sulfonating agent is sulfur trioxide, and the mass ratio of sulfur trioxide to the solvent is 1%-30%.

3. The sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 1, characterized in that: The sulfonation reaction is carried out at a temperature of 10-60°C.

4. The sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 1, characterized in that: The following preparation method is adopted: the raw material and the sulfonating agent are mixed with the solvent respectively and then subjected to sulfonation reaction, and then neutralized with an alkaline aqueous solution after the reaction, and passed into a dryer for drying to obtain a powdery product.

5. The sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 4, characterized in that: The alkaline aqueous solution is an aqueous solution of any concentration of any one of sodium hydroxide, potassium hydroxide and ammonia.

6. The sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 4, characterized in that: The temperature of the neutralization reaction is maintained at 10-60°C.

7. A method for preparing sulfonated asphalt for water-based mud resistant to high temperature and high pressure, characterized in that: The raw materials and the sulfonating agent are mixed with the solvent respectively, and then the sulfonation reaction is carried out, and then the mixture is neutralized with an alkaline aqueous solution and dried to obtain a powdered product. The raw materials include any one or a combination of heavy oil, modified heavy oil, asphalt, modified asphalt, coal asphalt, natural asphalt, plant asphalt, SEBS, and the solvent is a normal or isomeric alkane with a total carbon atom number of 1-5, obtained by replacing 1-3 hydrogen atoms.

8. The method for preparing sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 7, characterized in that: The temperature of the sulfonation reaction is 10-60° C., the temperature of the neutralization reaction is 10-60° C., and the neutralization reaction is performed using an aqueous solution of any concentration including sodium hydroxide, potassium hydroxide, and ammonia.

9. The method for preparing sulfonated asphalt for water-based mud resistant to high temperature and high pressure according to claim 7, characterized in that: The mass ratio of the raw material to the solvent is 1%-50%, the sulfonating agent is sulfur trioxide, and the mass ratio of sulfur trioxide to the solvent is 1%-30%.

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