Strong adsorption type drilling fluid wetting agent capable of resisting temperature of-45 DEG C for polar region drilling as well as preparation method and application thereof

Abstract

The invention provides a strong adsorption type drilling fluid wetting agent capable of resisting the temperature of-45 DEG C for polar region drilling as well as a preparation method and application thereof, and belongs to the technical field of polar region drilling. The wetting agent is prepared from the following raw materials: alkylamine polyoxyethylene ether, an amino compound and dimethylacetamide. Wherein the alkylamine polyoxyethylene ether is one of octadecylamine polyoxyethylene ether or dodecylamine polyoxyethylene ether; the amino compound is one of hydroxyurea or 5-hydroxytryptamine. The wetting agent is simple in raw material composition and preparation method, and the obtained wetting agent is safe, environmentally friendly and free of pungent smell; the wetting agent is applied to the drilling fluid for polar region drilling, can improve the ultralow-temperature dispersion performance and colloid performance of the drilling fluid, effectively solves the problem that the dispersion performance of organic soil in the drilling fluid is poor under the ultralow-temperature condition, and further improves the polar region drilling efficiency.

Description

Technical Field

[0001] The invention relates to a strong adsorption type temperature-resistant -45 DEG C drilling fluid wetting agent for polar drilling and a preparation method and application thereof, belonging to the technical field of polar drilling. Background Art

[0002] Polar (such as Antarctica) drilling fluid is a thermodynamically unstable system with base oil as the external phase. Organic soil in polar drilling fluid usually exhibits poor dispersibility and easy sedimentation, resulting in deterioration of drilling fluid performance. Therefore, it is very important to develop a wetting material that can effectively improve the dispersion and colloid properties of polar drilling fluid systems.

[0003] At present, in the development of deep oil and gas, scholars have done a lot of research on the research and development of high-temperature resistant drilling fluid wetting agents. Chinese patent document CN104789196A discloses a wetting agent for oil-based drilling fluid and a preparation method thereof. The invention mainly modifies lecithin by amidation to make it have good wetting properties and effectively improve its temperature resistance and electrical stability. Chinese patent document CN103194187A discloses a wetting agent for high-density oil-based drilling fluid and its application. The invention is made by mixing Span 80 and Tween 80 in a specific proportion, which can have a good wetting effect on barite in high-density oil-based drilling fluid. Chinese patent document CN103694968A discloses an amide-amine oil-based drilling fluid wetting agent and a preparation method thereof. The wetting agent is prepared by amidation using fatty acids as raw materials. Studies have shown that it has good suspension properties for solid particles and also has a significant improvement on the rock carrying properties and rheological properties of the drilling fluid. However, there is no relevant report on the research of wetting agents for polar ultra-low temperature drilling fluids.

[0004] At present, there is no report on the research of ultra-low temperature resistant drilling fluid wetting agents for polar drilling. Therefore, it is urgent to develop ultra-low temperature drilling fluid wetting agents suitable for polar regions to improve the ultra-low temperature dispersion performance and colloid properties of drilling fluids, thereby improving drilling efficiency. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling, and a preparation method and application thereof. The raw material composition and preparation method of the wetting agent of the present invention are simple, and the obtained wetting agent is safe, environmentally friendly, and has no irritating odor; the wetting agent of the present invention is applied to drilling fluid for polar drilling, which can improve the ultra-low temperature dispersion performance and colloid performance of the drilling fluid, effectively solve the problem of poor dispersion performance of organic soil in drilling fluid under ultra-low temperature conditions, and thus improve the efficiency of polar drilling.

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

[0007] A strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling, prepared from the following raw materials: alkylamine polyoxyethylene ether, amino compound, dimethylacetamide;

[0008] Among them, the molar ratio of alkylamine polyoxyethylene ether and amino compound is 1:(1.5-2.2); the mass of dimethylacetamide is 60-65% of the total mass of alkylamine polyoxyethylene ether and amino compound; alkylamine polyoxyethylene ether is one of octadecylamine polyoxyethylene ether or dodecylamine polyoxyethylene ether; and the amino compound is one of hydroxyurea or 5-hydroxytryptamine.

[0009] Preferably according to the present invention, the alkylamine polyoxyethylene ether is octadecylamine polyoxyethylene ether.

[0010] According to the present invention, preferably, the amino compound is hydroxyurea.

[0011] Preferably according to the present invention, the molar ratio of the alkylamine polyoxyethylene ether to the amino compound is 1:(1.6-1.8).

[0012] The preparation method of the above-mentioned strong adsorption type temperature-resistant -45°C drilling fluid wetting agent for polar drilling includes the steps of: fully mixing and dispersing alkylamine polyoxyethylene ether, amino compound and dimethylacetamide, reacting, filtering and distilling under reduced pressure to obtain the strong adsorption type drilling fluid wetting agent for polar drilling.

[0013] According to the present invention, the reaction is preferably carried out in the absence of oxygen and under the protection of a protective gas; the protective gas is nitrogen or argon.

[0014] Preferably, according to the present invention, the reaction temperature is 140° C. to 160° C., the reaction time is 4 to 6 hours, and the reaction is carried out under stirring conditions at a stirring rate of 350 to 400 r / min.

[0015] Preferably, the reaction temperature is 150° C. to 160° C., the reaction time is 5 to 6 hours, and the stirring rate is 350 to 370 r / min.

[0016] The application of the above-mentioned strong adsorption type temperature-resistant -45°C drilling fluid wetting agent for polar drilling in polar formation drilling.

[0017] Preferably according to the present invention, the polar region is Antarctica.

[0018] Preferably according to the present invention, the wetting agent is used in drilling fluid for polar formations.

[0019] The technical features and beneficial effects of the present invention are as follows:

[0020] 1. The raw material composition and preparation method of the wetting agent of the present invention are simple, and the obtained wetting agent is safe, environmentally friendly and has no irritating odor.

[0021] 2. The wetting agent in the present invention is synthesized from two monomers, alkylamine polyoxyethylene ether and hydroxyurea (or 5-hydroxytryptamine) (mainly through the condensation reaction between the hydroxyl and amino groups between the monomers, and dimethylacetamide is used as a solvent). The wetting agent of the present invention is applied to drilling fluid for polar drilling. The wetting agent molecules are well compatible with the base oil due to their lipophilic long carbon chains. In addition, it has a variety of strong polar groups, such as hydroxyl, amine, imino and carbonyl groups. These strong polar groups can be strongly adsorbed on the surface of organic soil particles, significantly improving the lipophilicity of organic soil in base oil, changing the original "face-to-face connection" to "end-to-end or end-face" connection, forming a spatial grid structure, and thus improving the ultra-low temperature dispersion performance and ultra-low temperature colloidal stability of the drilling fluid. At the same time, the wetting agent of the present invention is applied to drilling fluid for polar drilling, and the obtained drilling fluid exhibits good low-temperature rheological properties.

[0022] 3. The monomers used in the preparation of the wetting agent of the present invention are optimally combined in specific types and specific ratios, and work together to achieve the excellent effects of the present invention. The types of the alkylamine polyoxyethylene ether and the amino compound of the present invention need to be appropriate. If not, the performance of the resulting wetting agent will be reduced. The molar ratio of the alkylamine polyoxyethylene ether and hydroxyurea (or 5-hydroxytryptamine) in the present invention needs to be appropriate. If not, the performance of the wetting agent will be reduced; if the ratio is too low, the unreacted hydroxyurea (or 5-hydroxytryptamine) will affect the molecular spatial structure of the target product, thereby affecting its wettability in the drilling fluid. At the same time, the suitability of the reaction time is also directly related to the purity of the reaction product, thereby affecting the performance of the wetting agent; if the reaction time is too short, it will lead to incomplete generation of the target product, thereby affecting the conversion rate of the reaction product and the performance of the wetting agent. DETAILED DESCRIPTION

[0023] The present invention will be further described below by means of specific examples, but is not limited thereto.

[0024] The experimental methods described in the examples are conventional methods unless otherwise specified; the reagents and materials used are commercially available unless otherwise specified.

[0025] In the examples, octadecylamine polyoxyethylene ether, total amine value mgKOH / g: 44-50, was purchased from MacLean Reagent Company. Dodecylamine polyoxyethylene ether: Mw: 317, oil-soluble, purchased from MacLean Reagent Company. Tallow amine polyoxyethylene ether, total amine value (mgKOH / g): 115±4, was purchased from MacLean Reagent Company.

[0026] Example 1

[0027] A method for preparing a strong adsorption-type temperature-resistant -45°C drilling fluid wetting agent for polar drilling comprises the following steps:

[0028] (1) Adding octadecylamine polyoxyethylene ether and hydroxyurea to dimethylacetamide, mixing and dispersing the mixture thoroughly, and introducing nitrogen for 15 minutes to make the reaction system completely anaerobic;

[0029] (2) heating the reaction system to 155° C. and reacting at a constant temperature for 5 h at a stirring rate of 360 r / min;

[0030] (3) After the reaction is completed, the reaction product is cooled to room temperature, and the solvent is removed by filtration and reduced pressure distillation to obtain a strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling.

[0031] The mass of dimethylacetamide is 65% of the total mass of octadecylamine polyoxyethylene ether and hydroxyurea, and the molar ratio of octadecylamine polyoxyethylene ether to hydroxyurea is 1:1.8.

[0032] Example 2

[0033] A method for preparing a strong adsorption-type temperature-resistant -45°C drilling fluid wetting agent for polar drilling comprises the following steps:

[0034] (1) Adding octadecylamine polyoxyethylene ether and 5-hydroxytryptamine to dimethylacetamide, mixing and dispersing the mixture evenly, and introducing nitrogen for 15 minutes to make the reaction system completely anaerobic;

[0035] (2) heating the reaction system to 155° C. and reacting at a constant temperature for 5 h at a stirring rate of 360 r / min;

[0036] (3) After the reaction is completed, the reaction product is cooled to room temperature, and the solvent is removed by filtration and reduced pressure distillation to obtain a strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling.

[0037] The mass of dimethylacetamide is 65% of the total mass of octadecylamine polyoxyethylene ether and 5-hydroxytryptamine, and the molar ratio of octadecylamine polyoxyethylene ether to 5-hydroxytryptamine is 1:1.8.

[0038] Example 3

[0039] A method for preparing a strong adsorption-type temperature-resistant -45°C drilling fluid wetting agent for polar drilling comprises the following steps:

[0040] (1) Adding octadecylamine polyoxyethylene ether and hydroxyurea to dimethylacetamide, mixing and dispersing the mixture thoroughly, and introducing nitrogen for 15 minutes to make the reaction system completely anaerobic;

[0041] (2) heating the reaction system to 155° C. and reacting at a constant temperature for 5 h at a stirring rate of 360 r / min;

[0042] (3) After the reaction is completed, the reaction product is cooled to room temperature, and the solvent is removed by filtration and reduced pressure distillation to obtain a strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling.

[0043] The mass of dimethylacetamide is 65% of the total mass of octadecylamine polyoxyethylene ether and hydroxyurea, and the molar ratio of octadecylamine polyoxyethylene ether to hydroxyurea is 1:1.6.

[0044] Example 4

[0045] A method for preparing a highly adsorbable -45°C temperature-resistant drilling fluid wetting agent for polar drilling is as described in Example 1, except that in step (2), the reaction temperature is changed from 155°C to 140°C, and the other steps and conditions are the same as in Example 1.

[0046] Example 5

[0047] A method for preparing a highly adsorbable -45°C temperature-resistant drilling fluid wetting agent for polar drilling is as described in Example 1, except that the reaction time in step (2) is changed from 5 hours to 4 hours, and the other steps and conditions are the same as in Example 1.

[0048] Example 6

[0049] A method for preparing a highly adsorbable -45°C temperature-resistant drilling fluid wetting agent for polar drilling is as described in Example 1, except that in step (1), the molar ratio of octadecylamine polyoxyethylene ether to hydroxyurea is changed from 1:1.8 to 1:2.2, and the other steps and conditions are the same as those in Example 1.

[0050] Example 7

[0051] A method for preparing a highly adsorbable -45°C temperature-resistant drilling fluid wetting agent for polar drilling is as described in Example 1, except that in step (1), octadecylamine polyoxyethylene ether is replaced with dodecylamine polyoxyethylene ether, and the other steps and conditions are the same as those in Example 1.

[0052] Example 8

[0053] A method for preparing a highly adsorbable -45°C temperature-resistant drilling fluid wetting agent for polar drilling is as described in Example 1, except that in step (1), the mass of dimethylacetamide is changed to 60% of the total mass of octadecylamine polyoxyethylene ether and hydroxyurea, and the other steps and conditions are the same as those in Example 1.

[0054] Comparative Example 1

[0055] A cationic wetting agent: dioctadecyl dimethyl ammonium chloride (DODMAC).

[0056] Comparative Example 2

[0057] A method for preparing a drilling fluid wetting agent is as described in Example 1, except that in step (1), octadecylamine polyoxyethylene ether is replaced with tallow amine polyoxyethylene ether, and the other steps and conditions are the same as those in Example 1.

[0058] Comparative Example 3

[0059] A method for preparing a drilling fluid wetting agent is as described in Example 1, except that in step (1), hydroxyurea is replaced with anilinoacetonitrile, and the other steps and conditions are the same as those in Example 1.

[0060] Comparative Example 4

[0061] A method for preparing a drilling fluid wetting agent is as described in Example 1, except that in step (1), the mass of dimethylacetamide is changed to 70% of the total mass of octadecylamine polyoxyethylene ether and hydroxyurea, and the other steps and conditions are the same as those in Example 1.

[0062] Test Example 1

[0063] The wetting agents in Examples 1-8 and Comparative Examples 1-4 were tested for colloid rate, contact angle and rheological properties.

[0064] (1) Sample preparation:

[0065] The composition of the drilling fluid base fluid is as follows: first, 4# aviation kerosene and 5# white oil are prepared into a base oil in a volume ratio of 7:3, with a total of 350 mL; secondly, 3% of the mass of the base oil is added to T150 type organic clay (produced by Shanghai Wanzhao Fine Chemical Co., Ltd.) to prepare a drilling fluid base fluid; the wetting agents in the embodiments or comparative examples are added to the drilling fluid base fluid respectively, and the added amount is 2% of the mass of the base fluid, and the samples are fully stirred on a high-speed stirrer for 25 minutes to obtain samples; and the performance thereof at -45°C is tested.

[0066] (2) Test method:

[0067] Colloid rate test: Pour a certain amount of prepared drilling fluid into a colorimetric tube, then place the colorimetric tube in a low temperature constant temperature box (-45°C) and let it stand for 16 hours to calculate the colloid rate, colloid rate = (lower volume / total volume) * 100%. The lower volume refers to the volume of the colloid, and the upper volume is the volume of the clear liquid after sedimentation.

[0068] Rheological test: Pour a certain amount of prepared drilling fluid into the test slurry cup, use a low-temperature rheometer to test the 600r and 300r readings at -45°C, and then calculate the relevant rheological parameters.

[0069] Contact angle test: soak the mica sheet in the prepared drilling fluid and freeze it in a DW-40 ultra-low temperature constant temperature box at -45°C for 16 hours; then use a contact angle meter to test the contact angle, take out the mica sheet, use a 5.0μL oil droplet as a probe, test the contact angle between the oil droplet and the mica sheet, measure each sample three times, and record the average value.

[0070] The test results of colloid rate, rheological properties and contact angle are shown in Table 1.

[0071] Table 1 Performance test of drilling fluid wetting agent at -45℃

[0072]

[0073] It can be seen from the data in Table 1 that the drilling fluid wetting agent prepared by the present invention has good lipophilicity, and the contact angle can reach below 15.6°; it can effectively improve the dispersion performance of organic soil in base oil at -45°C, and the colloid rate can still reach more than 79.0% after standing for 16 hours; it also has a good shearing effect, and the shearing rate at -45°C can reach more than 100%, indicating that the wetting agent can also make the drilling fluid have good ultra-low temperature rheological properties.

[0074] In summary, the -45°C temperature-resistant drilling fluid wetting agent of the present invention can meet the needs of polar drilling.

[0075] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0076] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0077] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A strong adsorption type temperature-resistant -45°C drilling fluid wetting agent for polar drilling, characterized in that: The method comprises the following raw materials: alkylamine polyoxyethylene ether, amino compound, dimethylacetamide; Among them, the molar ratio of alkylamine polyoxyethylene ether and amino compound is 1:(1.5-2.2); the mass of dimethylacetamide is 60-65% of the total mass of alkylamine polyoxyethylene ether and amino compound; alkylamine polyoxyethylene ether is one of octadecylamine polyoxyethylene ether or dodecylamine polyoxyethylene ether; and the amino compound is one of hydroxyurea or 5-hydroxytryptamine.

2. The highly adsorbent -45°C temperature-resistant drilling fluid wetting agent for polar drilling according to claim 1, characterized in that: The alkylamine polyoxyethylene ether is octadecylamine polyoxyethylene ether.

3. The highly adsorbent -45°C temperature-resistant drilling fluid wetting agent for polar drilling according to claim 1, characterized in that: The amino compound is hydroxyurea.

4. The highly adsorbent -45°C temperature-resistant drilling fluid wetting agent for polar drilling according to claim 1, characterized in that: The molar ratio of the alkylamine polyoxyethylene ether to the amino compound is 1:(1.6-1.8).

5. The method for preparing a strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling as claimed in any one of claims 1 to 4, comprising the steps of: fully mixing and dispersing the alkylamine polyoxyethylene ether, the amino compound and dimethylacetamide, reacting, filtering and distilling under reduced pressure to obtain a strong adsorption type -45°C temperature-resistant drilling fluid wetting agent for polar drilling.

6. The method for preparing the highly adsorbent -45°C temperature-resistant drilling fluid wetting agent for polar drilling according to claim 5, characterized in that: The reaction is carried out in the absence of oxygen and under the protection of protective gas, the protective gas is nitrogen or argon; the reaction temperature is 140°C to 160°C, the reaction time is 4 to 6 hours, and the reaction is carried out under stirring conditions, and the stirring rate is 350 to 400 r / min.

7. The method for preparing the highly adsorbent -45°C temperature-resistant drilling fluid wetting agent for polar drilling according to claim 6, characterized in that: The reaction temperature is 150°C to 160°C, the reaction time is 5 to 6 hours, and the stirring rate is 350 to 370 r / min.

8. Use of the highly adsorbent -45°C temperature-resistant drilling fluid wetting agent for polar drilling as claimed in any one of claims 1 to 4 in polar formation drilling.

9. The use according to claim 8, characterized in that: The pole is Antarctica.

10. The use according to claim 8, characterized in that: The wetting agent is applied to drilling fluid for polar formations.

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