A temperature-resistant -35 celsius small molecule drilling fluid wetting agent for polar drilling, and a preparation method and application thereof

Abstract

The present application relates to a kind of polar drilling temperature-resistant-35 ℃ small molecule drilling fluid wetting agent and its preparation method and application.The preparation method is as follows: carboxylic acid and polyamine are added to toluene, and a reaction system is constructed;Then the reaction system is purged with nitrogen for 20~30min at room temperature, then constant temperature reaction is carried out at a reaction temperature of 150~180℃ and a stirring speed of 280~330r / min for 4~5h, after reaction is completed, it is cooled to 70~80℃, after the reaction product is filtered and solvent is removed by distillation under reduced pressure, polar drilling temperature-resistant-35 ℃ small molecule drilling fluid wetting agent is obtained.The small molecule drilling fluid wetting agent in the present application is synthesized by carboxylic acid, polyamine and toluene three monomers.Small molecule drilling fluid wetting agent mainly includes multiple amide groups and polar groups such as carbonyl group, can be strongly adsorbed on the surface and edge of organic soil sheet, so that the dispersibility of organic soil is improved under super low temperature conditions.

Description

TECHNICAL FIELD

[0001] The application relates to a temperature-resistant-35 DEG C small-molecule drilling fluid wetting agent for polar drilling and a preparation method and application thereof, and belongs to the technical field of polar drilling. BACKGROUND

[0002] The Antarctic continent is rich in resources, and there are as many as 220 proven mineral species. In the drilling process, drilling fluid is the blood of drilling and plays a role in suspending and carrying cuttings. However, the low surface temperature and complex geological environment under the ice in the Antarctic bring great challenges to drilling fluid technology. Organic soil has a broad application prospect in the field of polar drilling, but the dispersibility of organic soil in aviation kerosene and white oil is poor, and it is easy to settle, resulting in deterioration of the performance of drilling fluid. The wetting agent is one of the important treatment agents of the drilling fluid, which can be adsorbed on the surface of the organic soil particles through the interaction between the polar groups, and then make the organic soil more easily dispersed in aviation kerosene and white oil.

[0003] At present, there are many reports on the development of high-temperature-resistant drilling fluid wetting agents, and the developed wetting agents are mainly non-ionic or cationic wetting agents. For example, Chinese patent document CN116496767A discloses a wetting agent and a preparation method and application thereof. The application prepares an oil-based drilling fluid wetting agent that can resist a high temperature of 220 DEG C by using alkyl dimethyl carboxybetaine, 3-sulfopropyl alkyl dimethyl betaine, dioctyl sulfosuccinate and water as raw materials. The wetting agent can effectively wet the weighting material and drill cuttings in different base oils, and can also increase the demulsification voltage of the synthetic base drilling fluid from 429V to 537V, thereby ensuring the stability of the emulsion. In view of the problem that barite in the drilling fluid under high-density conditions is prone to settlement, thereby leading to low rheological performance of the drilling fluid, Chinese patent document CN103194187A discloses a wetting agent for high-density oil-based drilling fluid and the application thereof. In the application, Span-80 and Tween-80 are compounded in a certain proportion to develop a wetting agent, which effectively improves the problem of easy coalescence and settlement of barite in the drilling fluid under high-density conditions. The 1% wetting agent increases the demulsification voltage of the drilling fluid from 514V to 650V, and the stability of the emulsion is improved. Chinese patent document CN114605974A discloses an oil-based drilling fluid and a preparation method thereof. In the application, SRRH-O-WET is selected as the wetting agent, which effectively improves the dispersion performance and suspension performance of the weighting agent and reduces the aggregation of organic clay particles.

[0004] However, there is no report on a low-temperature-resistant drilling fluid wetting agent suitable for the Antarctic region. Therefore, it is urgent to develop an ultra-low-temperature drilling fluid wetting agent suitable for the Antarctic region to improve the dispersion performance of the organic soil in the base oil in the process of polar drilling, and thereby improve the drilling efficiency. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application provides a temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling, and a preparation method and application thereof.The small molecule drilling fluid wetting agent can resist a low temperature of-35 DEG C, can solve the problem of poor dispersibility of organic soil in the drilling fluid, and can improve the rheological property of the drilling fluid.

[0006] To achieve the above object, the technical scheme of the present application is as follows:

[0007] A preparation method of a temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0008] Carboxylic acid and polyamine are added to toluene to construct a reaction system; then the reaction system is purged with nitrogen for 20-30 min at room temperature, and then constant temperature reaction is carried out at a reaction temperature of 150-180 DEG C and a stirring speed of 280-330 r / min for 4-5 h; after the reaction is completed, the reaction product is cooled to 70-80 DEG C, and then the solvent is removed by filtration and reduced pressure distillation to obtain the temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling.

[0009] According to the present application, preferably, the mass fraction of toluene in the reaction system is 65-70 wt%.

[0010] According to the present application, preferably, the carboxylic acid is sebacic acid or myristic acid.

[0011] Further preferably, the carboxylic acid is sebacic acid.

[0012] According to the present application, preferably, the polyamine is N-ethylethylenediamine or tetraethylenepentamine.

[0013] Further preferably, the polyamine is tetraethylenepentamine.

[0014] According to the present application, preferably, the molar ratio of the carboxylic acid to the polyamine is (2.5-3):1.

[0015] According to the present application, preferably, the reaction temperature is 160-170 DEG C, and the stirring speed is 300-320 r / min.

[0016] The present application also provides a temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling, which is prepared by the above preparation method.

[0017] According to the present application, preferably, the temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling has a colloid rate of 76.4%-87.2% at-35 DEG C, a contact angle of 10.4 DEG -16.2 DEG, a dynamic shear force of 0.75-1.25 Pa, and a shear rate of 50%-150%.

[0018] According to the application, the temperature-resistant-35 DEG C small-molecule drilling fluid wetting agent for polar drilling is applied in a polar stratum.

[0019] The technical features and advantages of the application are as follows:

[0020] 1. The preparation method is simple, and the obtained small-molecule drilling fluid wetting agent is safe, environmentally friendly, and has no irritating odor.

[0021] 2. The monomers used to prepare the small-molecule drilling fluid wetting agent are optimally combined in a specific type and specific ratio, and work together to achieve the excellent effects of the application.

[0022] 3. The small-molecule drilling fluid wetting agent in the application is synthesized and prepared from carboxylic acid, polyamine, and toluene. The small-molecule drilling fluid wetting agent mainly includes multiple amide groups and carbonyl groups, which can be strongly adsorbed on the surface and edge of organic soil layers, so that the dispersibility of organic soil is improved under ultra-low temperature conditions.

[0023] 4. The molar ratio of carboxylic acid to polyamine in the application should be appropriate. If the ratio is too low, unreacted polyamine will affect the adsorption of the small-molecule drilling fluid wetting agent on the organic soil layer, and further affect the improvement of the oil-wetting property of the small-molecule drilling fluid wetting agent on the organic soil. At the same time, the amount of solvent added directly affects the conversion rate of the reaction product. If the amount of solvent added is too low, the conversion rate of the reaction product will be low.

[0024] 5. The temperature-resistant-35 DEG C small-molecule drilling fluid wetting agent can be used in the polar region below-35 DEG C ultra-low temperature, providing technical support for the development of polar drilling fluid treatment agents, and having a broad application prospect. DETAILED DESCRIPTION

[0025] The application will be further described below through specific examples, but is not limited thereto.

[0026] In the examples, the experimental methods are conventional methods unless otherwise specified, and the reagents and materials used are commercially available unless otherwise specified.

[0027] Example 1

[0028] A preparation method of a temperature-resistant-35 DEG C small-molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0029] The toluene is first added into a three-necked flask, and then the sebacic acid and tetraethylenepentamine are added into the toluene to construct a reaction system; then the reaction system is subjected to nitrogen blowing at room temperature for 25 min; then the temperature is increased to 165 DEG C, a condenser tube is added above the flask, and constant temperature reaction is carried out at a stirring speed of 310 r / min for 5 h, and after the reaction is completed, the temperature is cooled to 80 DEG C; the reaction product is filtered and subjected to reduced pressure distillation to remove the solvent, thereby obtaining the -35 DEG C small molecule drilling fluid wetting agent for polar drilling;

[0030] In the reaction system, the mass percentage of toluene is 65 wt%, and the molar ratio of sebacic acid to tetraethylenepentamine is 2.5:1.

[0031] Example 2

[0032] A preparation method of a -35 DEG C small molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0033] The toluene is first added into a three-necked flask, and then the sebacic acid and tetraethylenepentamine are added into the toluene to construct a reaction system; then the reaction system is subjected to nitrogen blowing at room temperature for 25 min; then the temperature is increased to 165 DEG C, a condenser tube is added above the flask, and constant temperature reaction is carried out at a stirring speed of 310 r / min for 5 h, and after the reaction is completed, the temperature is cooled to 80 DEG C; the reaction product is filtered and subjected to reduced pressure distillation to remove the solvent, thereby obtaining the -35 DEG C small molecule drilling fluid wetting agent for polar drilling;

[0034] In the reaction system, the mass percentage of toluene is 65 wt%, and the molar ratio of sebacic acid to tetraethylenepentamine is 2.7:1.

[0035] Example 3

[0036] A preparation method of a -35 DEG C small molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0037] The toluene is first added into a three-necked flask, and then the sebacic acid and tetraethylenepentamine are added into the toluene to construct a reaction system; then the reaction system is subjected to nitrogen blowing at room temperature for 25 min; then the temperature is increased to 165 DEG C, a condenser tube is added above the flask, and constant temperature reaction is carried out at a stirring speed of 310 r / min for 5 h, and after the reaction is completed, the temperature is cooled to 80 DEG C; the reaction product is filtered and subjected to reduced pressure distillation to remove the solvent, thereby obtaining the -35 DEG C small molecule drilling fluid wetting agent for polar drilling;

[0038] In the reaction system, the mass percentage of toluene is 65 wt%, and the molar ratio of sebacic acid to tetraethylenepentamine is 2.7:1.

[0039] Example 4

[0040] A preparation method of a temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0041] Toluene is first added to a three-necked flask, then sebacic acid and tetraethylenepentamine are added to the toluene to construct a reaction system; then the reaction system is subjected to nitrogen blowing at room temperature for 25 min; then the temperature is raised to 170 DEG C, a condenser tube is added above the flask, and constant temperature reaction is carried out at a stirring speed of 310 r / min for 4 h; after the reaction is completed, the temperature is cooled to 80 DEG C; the reaction product is filtered and subjected to reduced pressure distillation to remove the solvent, thereby obtaining the temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling.

[0042] In the reaction system, the mass fraction of toluene is 65 wt%, and the molar ratio of sebacic acid to tetraethylenepentamine is 2.7:1.

[0043] Example 5

[0044] A preparation method of a temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0045] Toluene is first added to a three-necked flask, then myristic acid and tetraethylenepentamine are added to the toluene to construct a reaction system; then the reaction system is subjected to nitrogen blowing at room temperature for 30 min; then the temperature is raised to 170 DEG C, a condenser tube is added above the flask, and constant temperature reaction is carried out at a stirring speed of 320 r / min for 5 h; after the reaction is completed, the temperature is cooled to 80 DEG C; the reaction product is filtered and subjected to reduced pressure distillation to remove the solvent, thereby obtaining the temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling.

[0046] In the reaction system, the mass fraction of toluene is 70 wt%, and the molar ratio of myristic acid to tetraethylenepentamine is 3:1.

[0047] Example 6

[0048] A preparation method of a temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling, comprising the following steps:

[0049] Toluene is first added to a three-necked flask, then sebacic acid and N-ethyl ethylenediamine are added to the toluene to construct a reaction system; then the reaction system is subjected to nitrogen blowing at room temperature for 20 min; then the temperature is raised to 160 DEG C, a condenser tube is added above the flask, and constant temperature reaction is carried out at a stirring speed of 300 r / min for 4 h; after the reaction is completed, the temperature is cooled to 70 DEG C; the reaction product is filtered and subjected to reduced pressure distillation to remove the solvent, thereby obtaining the temperature-resistant-35 DEG C small molecule drilling fluid wetting agent for polar drilling.

[0050] In the reaction system, the mass fraction of toluene is 65 wt%, and the molar ratio of sebacic acid to N-ethyl ethylenediamine is 2.5:1.

[0051] Comparative Example 1

[0052] A wetting agent was prepared according to the method described in Example 3, except that sebacic acid was used instead of camphoric acid, and other conditions were the same as in Example 3.

[0053] Comparative Example 2

[0054] A wetting agent was prepared according to the method described in Example 3, except that the molar ratio of sebacic acid to tetraethylenepentamine was 3.2:1, and other conditions were the same as in Example 3.

[0055] Comparative Example 3

[0056] A wetting agent was prepared according to the method described in Example 3, except that the reaction time was 6h.

[0057] Comparative Example 4

[0058] An amide wetting agent CHS-1 was prepared by mixing plant fatty acid, polyene polyamine and acid anhydride in a molar ratio of 7.5:2.5:1, and then uniformly mixing, and then reacting at 170°C for 5h.

[0059] Test Example 1

[0060] The wetting agents prepared in Examples 1-6 and Comparative Examples 1-4 were tested for colloidal rate, contact angle and rheological property.

[0061] (1) Sample preparation:

[0062] The base fluid of the drilling fluid was prepared as follows: first, 4# aviation kerosene and 5# white oil were mixed in a volume ratio of 7:3 to prepare a base oil, a total of 350mL; second, 3% of the organic clay (produced by Baker Oil Company) by mass of the base oil was added to prepare the base fluid of the drilling fluid; the wetting agents prepared in Examples 1-6 and Comparative Examples 1-4 were added to the base fluid of the drilling fluid, the amount of addition was 2% of the mass of the base fluid of the drilling fluid, and the mixture was fully stirred on a high-speed stirrer for 25min to obtain a sample; then the performance of the sample was tested at -35°C.

[0063] (2) Test method:

[0064] Colloidal rate test: 100mL of the prepared drilling fluid was poured into a colorimetric tube, and then the colorimetric tube was placed in a low-temperature constant-temperature box (-35°C) and stood for 16h, and then the colloidal rate was calculated, the colloidal rate=(lower volume / total volume)*100%.

[0065] Rheological property test: 100mL of the prepared drilling fluid was poured into a test slurry cup, and then a low-temperature rheometer was used to test the 600r and 300r readings at -35°C, and then the relevant rheological parameters were calculated.

[0066] Contact angle test: the wetting agent was added into the drilling fluid base fluid according to 2% of the mass of the drilling fluid base fluid, and stirred for 20 min, then the mica sheet was soaked in the drilling fluid, and frozen in a DW-40 type ultra-low temperature thermostat for 24 h; then the contact angle measuring instrument was used to test the contact angle, 5.0 μL oil droplets were used as probes, each sample was measured three times, and the average value was recorded.

[0067] The colloidal rate, rheological property and contact angle were measured, and the test results are shown in Table 1.

[0068] Table 1, performance test of drilling fluid wetting agent at-35℃

[0069]

[0070] As can be seen from the data in Table 1, the polar drilling temperature-resistant-35℃ small molecule drilling fluid wetting agent prepared by examples 1-6 has good lipophilicity, and the contact angle can be below 16.2°; the dispersion performance of organic soil in base oil can be effectively improved at-35℃, and the colloidal rate after standing for 16 h can still reach above 76.4%; it also has good fluid loss additive effect, the fluid loss rate at-35℃ can reach above 50%, and the plastic viscosity is below 16.5 mPa.s, indicating that the wetting agent also has good rheological property.

[0071] In summary, the temperature-resistant-35℃ small molecule drilling fluid wetting agent provided by the present application can meet the use under the ultra-low temperature below-35℃ in the polar region, and can meet the needs of polar drilling, providing technical support for the development of polar drilling fluid treatment agent, and having a broad application prospect.

[0072] The preferred embodiments of the present application are described in detail above, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application. In addition, it should be noted that each specific technical feature described in the above-described specific embodiments can be combined in any appropriate manner without contradiction, and in order to avoid unnecessary repetition, the present application will not further describe various possible combination manners. In addition, various different embodiments of the present application can also be combined in any manner, as long as it does not deviate from the idea of the present application, it should also be considered as disclosed by the present application.

Claims

1. A method for preparing a small-molecule drilling fluid wetting agent resistant to -35℃ for polar drilling, characterized in that, The steps include the following: Carboxylic acid and polyamine were added to toluene to construct a reaction system; then nitrogen gas was purged into the reaction system at room temperature for 20-30 min, followed by constant temperature reaction at 150-180℃ and stirring speed of 280-330 r / min for 4-5 h. After the reaction was completed, the mixture was cooled to 70-80℃, and the reaction product was filtered and the solvent was removed by vacuum distillation to obtain a small molecule drilling fluid wetting agent with a temperature resistance of -35℃ for polar drilling. Wherein, the carboxylic acid is sebacic acid or myristic acid; the polyamine is N-ethylethylenediamine or tetraethylenepentamine; and the molar ratio of the carboxylic acid to the polyamine is (2.5~3):

1.

2. The preparation method according to claim 1, characterized in that, The mass percentage of toluene in the reaction system is 65-70 wt%.

3. The preparation method according to claim 1, characterized in that, The carboxylic acid is sebacic acid.

4. The preparation method according to claim 1, characterized in that, The polyamine is tetraethylenepentamine.

5. The preparation method according to claim 1, characterized in that, The reaction temperature is 160~170℃, and the stirring speed is 300~320r / min.

6. A small-molecule drilling fluid wetting agent resistant to -35℃ for polar drilling, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 5.

7. The polar drilling fluid wetting agent with a temperature resistance of -35℃ for polar drilling as described in claim 6, characterized in that, The polar drilling fluid wetting agent with a temperature resistance of -35℃ has a colloidal content of 76.4%~87.2% at -35℃, a contact angle of 10.4°~16.2°, a dynamic shear force of 0.75~1.25Pa, and a shear lifting rate of 50%~150%.

8. The application of the polar drilling fluid wetting agent with a temperature resistance of -35℃ as described in claim 6 in polar formations.

9. The application as described in claim 8, characterized in that, The polar region mentioned is Antarctica.

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