Alkane polyol ether as wetting reversal agent for drilling fluid and preparation method and application thereof

Abstract

A wetting reversal agent alkane polyol ether for drilling fluid and its preparation and application, the wetting reversal agent alkane polyol ether for drilling fluid is made of ethylenediamine, monohalogenated alkane, 11-dodecenol, ethylene oxide, sodium hydroxide, vinyl pyridine, initiator, n-propanol, and deionized water. The preparation method includes first reacting ethylenediamine and monohalogenated alkane to obtain an intermediate product A, then polymerizing the intermediate product B obtained by reacting 11-dodecenol with ethylene oxide with vinyl pyridine to obtain an intermediate product C, and finally mixing the intermediate products A and C and filtering the water to obtain the wetting reversal agent alkane polyol ether for drilling fluid. The concentration of the wetting reversal agent alkane polyol ether for drilling fluid of the present invention is 0.10%, which can reduce the surface tension of the solution to a lower value, it has strong adsorption to the rock surface, can greatly enhance the hydrophilicity of the rock surface, has good wetting reversal performance, improves oil recovery efficiency, and is also conducive to improving cementing quality in the later stage.

Description

Technical Field

[0001] The present invention relates to a petroleum drilling auxiliary agent, in particular to a wetting reversal agent for drilling fluid, specifically to an alkane polyol ether wetting reversal agent for drilling fluid. The present invention also relates to a preparation method and application of the alkane polyol ether wetting reversal agent for drilling fluid. Background Art

[0002] Wettability reversal agent is a very important drilling fluid additive. It mainly changes the properties of the rock surface by reducing the surface tension of the (formation) rock surface and changing the wettability of the rock surface.

[0003] When drilling into an oil-wet rock layer, the wetting reversal agent in the drilling fluid can change the properties of the rock surface through adsorption, turning the oil-wet rock surface into a water-wet rock surface, effectively improving the oil recovery efficiency of the oil well, reducing operating costs, and also facilitating the improvement of cementing quality in the later stage.

[0004] Related patent literature: CN115820226A discloses a wettability reversal agent and its preparation method and application. The wettability reversal agent is prepared from fatty acid, organic amine, quaternary ammonium agent and diluent in a mass volume ratio of 1.8-2.2g: 0.8-1.2g: 0.8-1.2g: 0.2-0.4mL. CN113045701A discloses a wettability reversal agent for acidification, a preparation method, and a construction method thereof in a sandstone geothermal reservoir. The wettability reversal agent is a copolymer with a weight average molecular weight of 1200-3000g / mol obtained by polymerization of unsaturated quaternary ammonium salt and unsaturated phenol ether. The wettability reversal agent can effectively convert the solid surface from water-wet to oil-wet. The preparation method is simple and controllable, and the construction efficiency is high. CN115895629A discloses an amphiphilic sulfonated carbon nanotube / modified graphene oxide wettability reversal agent and its preparation method and application. The preparation method of the wettability reversal agent comprises sulfonating the carbon nanotubes, modifying the graphene oxide twice to obtain the modified graphene oxide 2, and finally polymerizing the fluorine-containing monomer on the surface of the modified graphene oxide 2 film to form a fluorine-containing polymer layer. The wettability reversal agent can change the wettability of the reservoir, changing the reservoir from hydrophilic and lipophilic to amphiphilic or super amphiphilic, thereby achieving the effect of reducing pressure and increasing injection.

[0005] The above technologies have not completely solved the problems of low oil recovery efficiency and high operating costs of oil wells. Currently, there are few types of wetting reversal agents for drilling fluids, and the technical improvements need to be further improved. Summary of the invention

[0006] The purpose of the present invention is to provide an alkane polyol ether as a wetting reversal agent for drilling fluid, which has good surface activity, can reduce the surface tension of the solution, has good adsorption performance on the rock surface, can enhance the hydrophilicity of the rock surface, and has good wetting reversal performance, thereby effectively improving the oil recovery efficiency of the oil well.

[0007] To this end, another object of the present invention is to provide a preparation method and application of the above-mentioned alkane polyol ether as a wetting reversal agent for drilling fluid.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0009] A wetting reversal agent alkane polyol ether for drilling fluid is prepared from the following raw materials in the following mass proportions (mass fractions): 10-15 parts of ethylenediamine, 5-8 parts of monohalogenated alkane, 1-3 parts of 11-dodecenol, 5-10 parts of ethylene oxide, 0.01-0.05 parts of sodium hydroxide; 0.5-2 parts of vinyl pyridine, 0.05-0.1 parts of initiator, 50-70 parts of n-propanol and 100 parts of deionized water.

[0010] The monohalogenated alkane is any one of dodecane bromide, tetradecane bromide and hexadecane bromide.

[0011] In the above technical scheme, a preferred technical scheme may be that the initiator may be any one of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, tert-butyl perbenzoate, diisopropylbenzene peroxide, and diisopropylbenzene hydroperoxide.

[0012] The preparation method of the drilling fluid wetting reversal agent alkane polyol ether comprises the following process steps:

[0013] (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 75-85° C., and obtain a solution X;

[0014] (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 to 1.5 hours, reacted at the above water bath temperature for 3 to 5 hours, and cooled to room temperature to obtain the intermediate product A;

[0015] (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, evacuate the air in the three-necked flask, and adjust the pressure; turn on the power, increase the temperature, stir at a speed of 250-300 r / min, introduce ethylene oxide, continue the reaction for 0.5-1h after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate product B;

[0016] (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 45-60°C, add the initiator, react at a stirring speed of 250-300 r / min for 4-6 hours, cool to room temperature, and obtain the intermediate product C;

[0017] (5) In a beaker, the intermediate product A and the intermediate product C are mixed evenly and the water is filtered off to obtain the wetting reversal agent alkane polyol ether for drilling fluid (final product).

[0018] In the above technical solution, a preferred technical solution may also be that in step (4), the viscosity average molecular weight (i.e., viscosity average molecular weight) of the intermediate product C is preferably in the range of 150,000 to 200,000. In step (3), the pressure is preferably adjusted to 0.1 MPa. In step (3), the temperature is preferably raised to 135 to 150°C.

[0019] The preparation method of the above-mentioned wetting reversal agent alkane polyol ether for drilling fluid mainly includes: firstly, ethylenediamine and monohalogenated alkane are reacted to obtain intermediate product A, then 11-dodecenol and ethylene oxide are reacted to obtain intermediate product B, and vinyl pyridine is polymerized to obtain intermediate product C, and finally the intermediate products A and C are mixed and the water is filtered to obtain the wetting reversal agent alkane polyol ether for drilling fluid.

[0020] The application of the wettability reversal agent alkane polyol ether in drilling fluid: when used, the wettability reversal agent alkane polyol ether can be directly added to the drilling fluid (mud), and the amount of the wettability reversal agent alkane polyol ether added to the (water-based) drilling fluid is 0.1% to 0.5% of the weight of the drilling fluid, for example, the amount added to the base slurry is 0.4% of the weight of the base slurry. In the oil drilling industry, the base slurry usually refers to the basic slurry used for drilling fluid, which can be a water-based type of slurry. When the wettability reversal agent alkane polyol ether of the present invention is added to the drilling fluid, it has good surface activity, reduces the surface tension of the solution (drilling fluid), has good adsorption performance on the rock surface, greatly enhances the hydrophilicity of the rock surface, has good wettability reversal performance, and has good use effect.

[0021] Compared with the prior art, the characteristics and beneficial effects of the present invention are as follows:

[0022] (1) The tetrameric quaternary ammonium salt cationic surfactant is synthesized using ethylenediamine and monohalogenated alkanes. It has two hydrophilic groups and four lipophilic groups, has greater advantages in interfacial activity, and greatly reduces the interfacial tension of the solution.

[0023] (2) The reaction product of 11-dodecenol and ethylene oxide is an unsaturated fatty alcohol polyoxyethylene ether, which is then polymerized with vinyl pyridine to obtain a saturated fatty alcohol polyoxyethylene ether containing a pyridine ring. It has the characteristics of both cationic surfactants and non-ionic surfactants, which further enhances its adsorption at the interface and enhances its wetting reversal ability.

[0024] In summary, the wetting reversal agent alkane polyol ether for drilling fluid of the present invention has good surface activity. Referring to the experimental part at the end of this specification, the surface tension of the solution can be reduced to a lower value of 15mN / m when the mass percentage concentration is 0.10%. The wetting reversal agent alkane polyol ether product solution is easily adsorbed on the rock surface, making the water-wet rock surface more hydrophilic, and the oil-wet rock surface is converted into a hydrophilic surface, which greatly enhances the hydrophilicity of the rock surface, has good wetting reversal performance, and has a good use effect. According to the test, compared with the existing related technology, after the wetting reversal agent alkane polyol ether of the present invention is added to the drilling fluid, the oil recovery efficiency of the oil well is effectively improved, the operating cost is reduced by more than 12%, and it is also beneficial to improve the cementing quality in the later stage. The present invention solves the problems of low oil recovery efficiency and high operating cost of oil wells. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described in conjunction with the embodiments below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on this embodiment, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the present invention.

[0026] Example 1: The wetting reversal agent alkane polyol ether for drilling fluid of the present invention is prepared from the following raw materials in the following mass proportion (mass fraction): 11 parts of ethylenediamine, 7 parts of monohalogenated alkane, 1.5 parts of 11-dodecenol, 6 parts of ethylene oxide, 0.02 parts of sodium hydroxide; 0.8 parts of vinyl pyridine, 0.06 parts of initiator, 55 parts of n-propanol, and 100 parts of deionized water. The monohalogenated alkane is dodecane bromide. The initiator is azobisisobutyronitrile.

[0027] In this embodiment, the preparation method of the drilling fluid wetting reversal agent alkane polyol ether comprises the following process steps:

[0028] (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 80° C., and obtain a solution X;

[0029] (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 hour, reacted at the above water bath temperature for 3.5 hours, and cooled to room temperature (25°C) to obtain the intermediate product A;

[0030] (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, exhaust the air in the three-necked flask, and adjust the pressure to 0.1 MPa; turn on the power, raise the temperature to 150°C, stir at 250 r / min, introduce ethylene oxide, continue the reaction for 1 hour after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate B;

[0031] (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 55° C., then add the initiator, react at a stirring speed of 250 r / min for 4.5 hours, cool to room temperature, and obtain the intermediate product C; the viscosity-average molecular weight of the intermediate product C is between 150,000 and 160,000;

[0032] (5) In a beaker, the intermediate product A and the intermediate product C are mixed evenly and the water is filtered off to obtain the wetting reversal agent alkane polyol ether for drilling fluid (final product).

[0033] Example 2: The wetting reversal agent alkane polyol ether for drilling fluid of the present invention is prepared from the following raw materials in the following mass proportion (mass fraction): 13 parts of ethylenediamine, 8 parts of monohalogenated alkane, 2.5 parts of 11-dodecenol, 8 parts of ethylene oxide, 0.04 parts of sodium hydroxide; 1 part of vinyl pyridine, 0.09 parts of initiator, 65 parts of n-propanol, and 100 parts of deionized water; the monohalogenated alkane is tetradecane bromide. The initiator is diisopropylbenzene hydroperoxide.

[0034] In this embodiment, the preparation method of the drilling fluid wetting reversal agent alkane polyol ether comprises the following process steps:

[0035] (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 85° C., and obtain a solution X;

[0036] (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 hour, reacted at the above water bath temperature for 4 hours, and cooled to room temperature (25°C) to obtain the intermediate product A;

[0037] (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, exhaust the air in the three-necked flask, and adjust the pressure to 0.1 MPa; turn on the power, raise the temperature to 140°C, stir at 300 r / min, introduce ethylene oxide, continue the reaction for 1 hour after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate product B;

[0038] (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 60° C., then add an initiator, react at a stirring speed of 300 r / min for 5 h, cool to room temperature, and obtain an intermediate product C; the viscosity-average molecular weight of the intermediate product C is between 160,000 and 170,000;

[0039] (5) In a beaker, mix the intermediate product A and the intermediate product C evenly, and drain the water to obtain the wetting reversal agent alkane polyol ether for drilling fluid.

[0040] Example 3: The wetting reversal agent alkane polyol ether for drilling fluid of the present invention is prepared from the following raw materials in the following mass proportions (mass fractions): 15 parts of ethylenediamine, 7.5 parts of monohalogenated alkane, 3 parts of 11-dodecenol, 9 parts of ethylene oxide, 0.05 parts of sodium hydroxide; 1.5 parts of vinyl pyridine, 0.09 parts of initiator, 70 parts of n-propanol, and 100 parts of deionized water. The monohalogenated alkane is hexadecane bromide. The initiator is diisopropylbenzene hydroperoxide.

[0041] In this embodiment, the preparation method of the drilling fluid wetting reversal agent alkane polyol ether comprises the following process steps:

[0042] (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 80° C., and obtain a solution X;

[0043] (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 hour, reacted at the above water bath temperature for 5 hours, and cooled to room temperature (25°C) to obtain the intermediate product A;

[0044] (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, exhaust the air in the three-necked flask, and adjust the pressure to 0.1 MPa; turn on the power, raise the temperature to 135°C, stir at 300 r / min, introduce ethylene oxide, continue the reaction for 0.5 h after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate product B;

[0045] (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 58°C, add initiator, react at a stirring speed of 300 r / min for 4 hours, cool to room temperature, and obtain intermediate product C; the viscosity-average molecular weight of the intermediate product C is 190,000;

[0046] (5) In a beaker, mix the intermediate product A and the intermediate product C evenly, and drain the water to obtain the wetting reversal agent alkane polyol ether for drilling fluid.

[0047] Example 4: The wetting reversal agent alkane polyol ether for drilling fluid of the present invention is prepared from the following raw materials in the following mass proportions (mass fractions): 13 parts of ethylenediamine, 6 parts of monohalogenated alkane, 3 parts of 11-dodecenol, 8 parts of ethylene oxide, 0.05 parts of sodium hydroxide; 1.5 parts of vinyl pyridine, 0.08 parts of initiator, 68 parts of n-propanol, and 100 parts of deionized water. The monohalogenated alkane is hexadecane bromide. The initiator is benzoyl peroxide.

[0048] In this embodiment, the preparation method of the drilling fluid wetting reversal agent alkane polyol ether comprises the following process steps:

[0049] (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 80° C., and obtain a solution X;

[0050] (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 hour, reacted at the above water bath temperature for 4 hours, and cooled to room temperature (25°C) to obtain the intermediate product A;

[0051] (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, exhaust the air in the three-necked flask, and adjust the pressure to 0.1 MPa; turn on the power, raise the temperature to 150°C, stir at 250 r / min, introduce ethylene oxide, continue the reaction for 1 hour after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate B;

[0052] (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 55° C., then add an initiator, react at a stirring speed of 250 r / min for 5 h, cool to room temperature, and obtain an intermediate product C; the viscosity-average molecular weight of the intermediate product C is between 190,000 and 200,000;

[0053] (5) In a beaker, mix the intermediate product A and the intermediate product C evenly, and drain the water to obtain the wetting reversal agent alkane polyol ether for drilling fluid.

[0054] The following is the experimental part of the present invention:

[0055] Preparation Comparative Example:

[0056] Comparative Example 1: A wetting reversal agent for drilling fluid, using the same raw materials as those of Example 1 of the present invention except that the raw materials ethylenediamine and monohalogenated alkane are not added, and the intermediate product A component is missing in the prepared product.

[0057] Comparative Example 2: A wetting reversal agent for drilling fluid is prepared by using the same raw materials and preparation method as those of Example 1 of the present invention, except that the raw material vinylpyridine is not added.

[0058] Comparative Example 3: A wetting reversal agent for drilling fluid, except that the raw material 11-dodecenol and the raw material ethylene oxide are not added, the rest are the same raw materials as those in Example 1 of the present invention, and the prepared product does not contain fatty alcohol polyoxyethylene ether ( n =10).

[0059] The following are specific test conditions of the present invention:

[0060] Experiment 1, surface tension test.

[0061] The alkane polyol ether products of wetting reversal agents for drilling fluids prepared in the above embodiments of the present invention and the wetting reversal agent products for drilling fluids prepared in the comparative examples were respectively prepared into solutions with mass percentage concentrations of 0.05%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, and 0.40%. The surface tension of the solutions was tested using a JYW-200A automatic interfacial tension meter according to the instructions. The results are shown in Table 1. The unit of surface tension in Table 1 is mN / m.

[0062] Experiment 2: Wetting reversal performance test.

[0063] (1) The water-wet core was extracted, cleaned and dried at low temperature. After cooling to room temperature, 1 drop of formation water was dripped onto the end face of the core, and the contact angle was measured using a JC2000CM contact angle meter according to the experimental instructions. The end face of the core was cleaned, dried and placed in a solution of each embodiment (wetting reversal agent alkane polyol ether product for drilling fluid) and each comparative example (wetting reversal agent product for drilling fluid) with a mass percentage concentration of 0.10%, soaked for 36 hours and then placed in an oven for low temperature drying. 1 drop of formation water was dripped onto the end face of the core, and the contact angle was measured using a JC2000CM contact angle meter according to the experimental instructions.

[0064] (2) The oil-wet core was extracted, cleaned and dried at low temperature. After cooling to room temperature, 1 drop of formation water was dripped onto the end face of the core, and the contact angle was measured using a JC2000CM contact angle meter according to the experimental instructions. The end face of the core was cleaned, dried and placed in a solution of each embodiment (wetting reversal agent alkane polyol ether product for drilling fluid) and each comparative example (wetting reversal agent product for drilling fluid) with a mass percentage concentration of 0.10%, soaked for 36 hours and then placed in an oven for low temperature drying. 1 drop of formation water was dripped onto the end face of the core, and the contact angle was measured using a JC2000CM contact angle meter according to the experimental instructions.

[0065] The wetting reversal performance data is shown in Table 2.

[0066] Table 1 Surface tension of solutions of various embodiments of the present invention and comparative examples at different concentrations

[0067]

[0068] It can be seen from the data in Table 1 that the products of Examples 1, 2, 3 and 4 of the present invention have good surface activity and can significantly reduce the surface tension of distilled water. When the addition amount is 0.10% (mass percentage concentration), the surface tension of the solution is reduced to 15 mN / m.

[0069] Table 2 Test results of rock wetting reversal performance of various examples of the present invention and comparative examples

[0070]

[0071] It can be seen from the data in Table 2 that, for the rocks that were originally water-wet, after being soaked in the wettability reversal agent alkane polyol ether of the present invention, the wetting angle of the rock surface is significantly reduced from the original 78.3° to below 36.1°, and the hydrophilicity of the rock surface is stronger; for the rocks that were originally oil-wet, after being soaked in the wettability reversal agent alkane polyol ether of the present invention, the wetting angle is reduced from the original 126.3° to below 48.2°, and the rock surface changes from oil-wet to obvious water-wet.

[0072] As can be seen from Table 1 and Table 2, the wetting reversal agent alkane polyol ether for drilling fluid of the present invention has good surface activity, greatly reduces the surface tension of the solution, has good adsorption performance on the rock surface, and greatly enhances the hydrophilicity of the rock surface. However, the performance of Comparative Examples 1, 2, and 3 is poor. The performance results of each comparative example show that the raw materials used in the present invention are necessary, and the synergistic effect of each component (raw material) enables the wetting reversal agent alkane polyol ether of the present invention to produce the above-mentioned good technical effects.

[0073] In summary, the above embodiments of the present invention provide a wetting reversal agent alkane polyol ether for drilling fluid, which has good surface activity. When the mass percentage concentration is 0.10%, the surface tension of the solution can be reduced to a lower (close to the minimum) value of 15mN / m. The wetting reversal agent alkane polyol ether product solution is easily adsorbed on the rock surface, making the water-wet rock surface more hydrophilic, and the oil-wet rock surface is converted into a hydrophilic surface, which greatly enhances the hydrophilicity of the rock surface, has good wetting reversal performance, and has good use effect. According to the test, compared with the existing related technology, after the wetting reversal agent alkane polyol ether of the present invention is added to the drilling fluid, the oil recovery efficiency of the oil well is effectively improved, the operating cost is reduced by more than 12%, and it is also beneficial to improve the cementing quality in the later stage. The present invention solves the problems of low oil recovery efficiency and high operating cost of oil wells.

Claims

1. A wetting reversal agent alkane polyol ether for drilling fluid, characterized in that: It is made of the following raw materials in the following quality ratios: 10-15 parts of ethylenediamine, 5-8 parts of monohalogenated alkane, 1-3 parts of 11-dodecenol, 5-10 parts of ethylene oxide, 0.01-0.05 parts of sodium hydroxide; 0.5-2 parts of vinyl pyridine, 0.05-0.1 parts of initiator, 50-70 parts of n-propanol, and 100 parts of deionized water; The monohalogenated alkane is one of dodecane bromide, tetradecane bromide and hexadecane bromide; The preparation method of the drilling fluid wetting reversal agent alkane polyol ether comprises the following process steps: (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 75-85° C., and obtain a solution X; (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 to 1.5 hours, reacted at the above water bath temperature for 3 to 5 hours, and cooled to room temperature to obtain the intermediate product A; (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, evacuate the air in the three-necked flask, and adjust the pressure; turn on the power, increase the temperature, stir at a speed of 250-300 r / min, introduce ethylene oxide, continue the reaction for 0.5-1h after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate product B; (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 45-60°C, add the initiator, react at a stirring speed of 250-300 r / min for 4-6 hours, cool to room temperature, and obtain the intermediate product C; (5) In a beaker, mix the intermediate product A and the intermediate product C evenly, and drain the water to obtain the wetting reversal agent alkane polyol ether for drilling fluid.

2. The wetting reversal agent alkane polyol ether for drilling fluid according to claim 1, characterized in that The initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, tert-butyl perbenzoate, diisopropylbenzene peroxide and diisopropylbenzene hydroperoxide.

3. The method for preparing the wetting reversal agent alkane polyol ether for drilling fluid according to any one of claims 1 to 2, characterized in that It includes the following process steps: (1) Add ethylenediamine to a round-bottom flask containing n-propanol according to the above mass ratio and stir evenly to obtain an intermediate solution, place the round-bottom flask containing the intermediate solution in a water bath, adjust the water bath temperature to 75-85° C., and obtain a solution X; (2) According to the above mass ratio, the monohalogenated alkane is gradually added dropwise into the solution X within 1 to 1.5 hours, reacted at the above water bath temperature for 3 to 5 hours, and cooled to room temperature to obtain the intermediate product A; (3) According to the above mass ratio, take another three-necked flask, add 11-dodecenol and sodium hydroxide into the three-necked flask, put the three-necked flask into an oil bath, introduce nitrogen, evacuate the air in the three-necked flask, and adjust the pressure; turn on the power, increase the temperature, stir at a speed of 250-300 r / min, introduce ethylene oxide, continue the reaction for 0.5-1h after the introduction is completed, cool to room temperature, stop introducing nitrogen, and obtain intermediate product B; (4) Add vinyl pyridine and deionized water to the three-necked flask containing the intermediate product B according to the above mass ratio, stir evenly, introduce nitrogen, raise the temperature to 45-60°C, add the initiator, react at a stirring speed of 250-300 r / min for 4-6 hours, cool to room temperature, and obtain the intermediate product C; (5) In a beaker, mix the intermediate product A and the intermediate product C evenly, and drain the water to obtain the wetting reversal agent alkane polyol ether for drilling fluid.

4. The method for preparing the wetting reversal agent alkane polyol ether for drilling fluid according to claim 3, characterized in that In step (4), the viscosity-average molecular weight of the intermediate product C is in the range of 150,000 to 200,000.

5. The method for preparing the wetting reversal agent alkane polyol ether for drilling fluid according to claim 3, characterized in that In step (3), the pressure is adjusted to 0.1 MPa.

6. The method for preparing the wetting reversal agent alkane polyol ether for drilling fluid according to claim 3, characterized in that In step (3), the temperature is raised to 135-150°C.

7. Use of the wettability reversal agent alkane polyol ether according to any one of claims 1 to 2 in drilling fluid.

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