Preparation method and application of a biomass synthetic-based wetting agent for drilling fluid

Abstract

The present invention provides a method for preparing a wetting agent for biomass synthetic-based drilling fluid, comprising: mixing cardanol, polyformaldehyde, a catalyst, and a solvent for a certain time, and then adding sultone to react for a certain time to obtain a wetting agent. The wetting agent prepared by the present invention is a gemini wetting agent containing hydrophilic groups such as a benzene ring, a hydroxyl group, and a sulfonic acid group, and cardanol as a lipophilic group. The wetting agent is modified from natural phenol and has the characteristics of being green, environmentally friendly, non-toxic, easily degradable, and low in cost. In terms of performance, it has strong wetting reversal ability and solid phase dispersion ability, effectively improves the sedimentation stability of high-density drilling fluid, and assists in improving emulsification stability. It can withstand temperatures up to 220°C and is not only suitable for drilling fluids with a density of 1.2g / cm 3 ~2.5g / cm 3 The biomass synthetic-based drilling fluid is also applicable to mineral oil-based and gas-to-liquid-based drilling fluids. The present invention also provides an application of a wetting agent for biomass synthetic-based drilling fluid.

Description

Technical Field

[0001] The invention belongs to the technical field of drilling fluids, and in particular relates to a preparation method and application of a wetting agent for biomass synthetic-based drilling fluids. Background Art

[0002] As the pace of exploration and development accelerates, with exploration and development extending into deeper and ultra-deep formations, deep and ultra-deep well drilling technologies are constantly improving both domestically and internationally, and their application is expanding. This has led to increasingly severe issues with drilling fluids under high-temperature, high-pressure conditions, placing increasing demands on drilling fluid performance, such as sedimentation stability. Sedimentation of drilling fluids under these conditions significantly increases the likelihood of complications downhole, severely impacting normal on-site operations and causing unnecessary losses.

[0003] Wetting agents, also known as wetting reversal agents, are commonly used drilling fluid treatment agents for oil-based and synthetic-based drilling fluids. The addition of a wetting agent can transform the surface of hydrophilic solid phases in the drilling fluid, such as barite and drill cuttings, into a lipophilic surface, thereby ensuring that the solid phase can be effectively suspended in the oil phase and improving the sedimentation stability of the drilling fluid under high temperature and high pressure. Currently, the most commonly used wetting agents are quaternary ammonium salts, sulfonates, alcohol ethers, and esters. Although these wetting agents are widely used, they still have many problems. For example, they have poor compatibility with base oils and limited use; low wetting efficiency and require large dosages, which gradually increase with increasing drilling fluid density; poor temperature resistance and easy decomposition under high temperature conditions. Therefore, it is necessary to develop a wetting agent that can be added in a low dosage, has good effects, and has strong temperature resistance. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a preparation method and application of a biomass synthetic-based wetting agent for drilling fluid. The wetting agent prepared by the method provided by the present invention has strong wetting reversal ability and temperature resistance, can be adsorbed on the surface of solid particles, improve the dispersion ability of the hydrophilic solid phase in the oil phase, and effectively avoid the sedimentation of the solid particles.

[0005] The present invention provides a method for preparing a biomass synthetic-based wetting agent for drilling fluid, comprising:

[0006] Carbohydrate, paraformaldehyde, a catalyst and a solvent are subjected to a first reaction to obtain a reaction product;

[0007] The reaction product is subjected to a second reaction with sultone to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0008] Preferably, the molar ratio of cardanol, paraformaldehyde and sultone is 2.0:(1.1-1.4):2.0;

[0009] The mass of the catalyst is 1-3% of the mass of cardanol.

[0010] The amount of the solvent used is 30-50% of the total mass of cardanol, paraformaldehyde, catalyst and sultone.

[0011] Preferably, the catalyst is selected from one or more of hydrochloric acid, oxalic acid, and succinic acid.

[0012] Preferably, the sultone is selected from one or more of propane sultone and butane sultone.

[0013] Preferably, the solvent is selected from one or more of dodecyl methyl ether, lauryl amyl ether and tetradecyl butyl ether.

[0014] Preferably, the first reaction temperature is 110-120°C.

[0015] Preferably, the temperature of the second reaction is 135-145°C.

[0016] The present invention provides a drilling fluid, comprising: the biomass synthetic-based drilling fluid wetting agent described in the above technical solution, or the biomass synthetic-based drilling fluid wetting agent prepared by the method described in the above technical solution.

[0017] Preferably, the drilling fluid is selected from one or more of biomass synthetic-based drilling fluid, mineral oil-based drilling fluid and gas-to-liquid-based drilling fluid.

[0018] Compared with wetting agents with traditional structures, gemini-type wetting agents have lower critical micelle concentrations and stronger adsorption capacity; however, the synthesis process of gemini surfactants is relatively complex, with many by-products and side reactions and high costs. Therefore, the present invention uses natural materials as the main modified raw materials to synthesize a gemini-type wetting agent with strong temperature resistance and high performance. The gemini-type wetting agent is suitable not only for biomass synthetic-based drilling fluids, but also for mineral oil-based drilling fluids, and has good application value.

[0019] The wetting agent prepared by the preparation method of the biomass synthetic-based drilling fluid provided by the present invention has strong wetting reversal ability and temperature resistance, can be adsorbed on the surface of solid particles, improves the dispersion ability of the hydrophilic solid phase in the oil phase, and effectively avoids the sedimentation of the solid particles. DETAILED DESCRIPTION

[0020] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0021] The present invention provides a method for preparing a biomass synthetic-based gemini wetting agent for drilling fluid, comprising:

[0022] Carbohydrate, paraformaldehyde, a catalyst and a solvent are subjected to a first reaction to obtain a reaction product;

[0023] The reaction product is subjected to a second reaction with sultone to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0024] In the present invention, the catalyst is preferably selected from one or more of hydrochloric acid, oxalic acid, and succinic acid, more preferably oxalic acid.

[0025] In the present invention, the solvent is preferably selected from one or more of dodecyl methyl ether, lauryl amyl ether and tetradecyl butyl ether, more preferably tetradecyl butyl ether.

[0026] In the present invention, the temperature of the first reaction is preferably 110-120° C., more preferably 120° C.; the time of the first reaction is preferably 2-4 h, more preferably 3 h.

[0027] In the present invention, the sultone is preferably selected from one or more of propane sultone and butane sultone, more preferably butane sultone.

[0028] In the present invention, the temperature of the second reaction is preferably 135-145° C., more preferably 140° C.; the time of the second reaction is preferably 4-5 h, more preferably 5 h.

[0029] In the present invention, the mass of the catalyst is preferably 1% to 3% of the mass of cardanol, more preferably 2%.

[0030] In the present invention, the molar ratio of cardanol, paraformaldehyde and sultone is preferably 2.0:(1.1-1.4):2.0, more preferably 2.0:1.3:2.0.

[0031] In the present invention, the mass of the solvent is preferably 30% to 50% of the total mass of the reactants (including the mass of cardanol, paraformaldehyde, catalyst and sultone), more preferably 30%.

[0032] The present invention provides a drilling fluid, comprising: the biomass synthetic-based drilling fluid wetting agent described in the above technical solution, or the biomass synthetic-based drilling fluid wetting agent prepared by the method described in the above technical solution.

[0033] In the present invention, the drilling fluid is preferably selected from one or more of biomass synthetic-based drilling fluid, mineral oil-based drilling fluid and gas-to-liquid-based drilling fluid.

[0034] In the present invention, the drilling fluid preferably comprises:

[0035] Biomass base fluid, calcium chloride solution, organic soil, emulsifier, wetting agent, oxidized asphalt, calcium chloride solution, calcium oxide, barite.

[0036] The present invention has no special restrictions on the type and source of the biomass-based liquid. A biomass-based liquid familiar to those skilled in the art can be used, such as the one that can be obtained according to the method disclosed in patent application number 201810743989.3.

[0037] In the present invention, the lubricant is consistent with the wetting agent for biomass synthetic-based drilling fluid described in the above technical solution, and will not be described in detail here.

[0038] In the present invention, the calcium chloride solution is preferably a calcium chloride aqueous solution, and the mass concentration of the calcium chloride solution is preferably 15-25%, more preferably 20%.

[0039] In the present invention, the volume ratio of the biomass-based liquid to the calcium chloride solution is preferably (7-9):(1-3), more preferably 8:2.

[0040] In the present invention, the total volume of the biomass base liquid and the calcium chloride solution is recorded as the solution volume, the mass volume ratio of the organic soil in the solution volume (the mass of the treatment agent added per 100 mL of the mixed solution, g / 100 mL) is preferably 1-3%, more preferably 2%; the mass volume ratio of the emulsifier in the solution volume is preferably 4-8%, more preferably 5-7%, and most preferably 6%; the mass volume ratio of the lubricant in the solution volume is preferably 0.5-1.5%, more preferably 0.8-1.2%, and most preferably 1%; the mass volume ratio of the oxidized asphalt in the solution volume is preferably 3-5%, more preferably 4%; the mass volume of the calcium oxide in the solution volume is preferably 2-4%, more preferably 3%; the amount of the barite is preferably such that the density of the drilling fluid is 1.2 g / cm 3 ~2.7g / cm 3 , more preferably 1.5 g / cm 3 ~2.5g / cm 3 .

[0041] In the present invention, the method for preparing the drilling fluid preferably comprises:

[0042] Organic soil, emulsifier, wetting agent and oxidized asphalt are added to the biomass base fluid for the first high-speed stirring, and then calcium chloride solution is added for the second high-speed stirring; then calcium oxide is added for the third high-speed stirring, and finally barite is added for the fourth high-speed stirring to obtain drilling fluid.

[0043] In the present invention, the time for the first high-speed stirring is preferably 8 to 12 minutes, more preferably 10 minutes; the time for the second high-speed stirring is preferably 4 to 6 minutes, more preferably 5 minutes; the time for the third high-speed stirring is preferably 1 to 3 minutes, more preferably 2 minutes; the time for the fourth high-speed stirring is preferably 15 to 25 minutes, more preferably 20 minutes.

[0044] The biomass synthesis-based drilling fluid gemini wetting agent provided by the present invention, its main raw material is extracted from cashew nut shell, is obtained by modification of natural materials, has a wide range of raw material sources, excellent environmental protection, and the characteristics of good biodegradability. The wetting agent provided by the present invention uses an alkyl group as a linking group to form a gemini wetting agent with a low critical micelle concentration and a strong adsorption capacity on the surface of solid particles. On the one hand, the sulfonic acid group in its molecular structure can be directional adsorbed on the solid surface, and the sulfonic acid group is a strong hydrophilic group that can penetrate into the inside of the solid particles, and its adsorption capacity is stronger, and because a wetting agent molecule contains two sulfonic acid groups, compared to a single molecule wetting agent, it is difficult to break away from the solid surface under high temperature conditions, so temperature resistance is stronger. On the other hand, after the wetting agent molecule is directional adsorbed on the solid surface, compared to a commonly used single molecule wetting agent, its bimolecular structure is due to intermolecular force, and is arranged more evenly, so that the hydrophilic solid particles are dispersed more fully in the oil phase, and are difficult to settle under high temperature conditions, making the stability of the drilling fluid higher. The biomass synthetic drilling fluid wetting agent provided by the present invention is applicable to a variety of drilling fluid systems, including diesel, white oil, biomass synthetic base, etc., with a density of 1.2 to 2.7 g / cm 3 The drilling fluid system has excellent temperature resistance, which can reach 220℃. It is especially suitable for high-density drilling fluids, ensuring its high temperature and sedimentation stability.

[0045] The cardanol in the embodiment of the present invention was purchased from Jining Huakai Resin Co., Ltd.; paraformaldehyde was purchased from Shandong Aldehyde Chemical Co., Ltd.; oxalic acid, succinic acid, propane sultone, and butane sultone acid were purchased from Aladdin Reagent (Shanghai) Co., Ltd.; dodecyl methyl ether and tetradecyl butyl ether were from the Drilling Engineering Technology Research Institute of Sinopec Zhongyuan Petroleum Engineering Co., Ltd.; the mineral oil was No. 0 diesel and No. 3 white oil; the biomass base liquid was prepared by the method of Example 1 in Patent 201810743989.3; organic soil was purchased from Zhejiang Fenghong New Materials Co., Ltd.; the emulsifier was prepared by the method of Example 1 in Patent CN107815298B; HIWET oil-based wetting agent was purchased from Jingzhou Jiahua Technology Co., Ltd. and belongs to fatty acids; HFWE wetting agent was purchased from Sichuan Honghua Oil and Gas Field Engineering Technology Co., Ltd. and belongs to phosphate esters; calcium oxide was purchased from Hubei Longhai Chemical Co., Ltd.; oxidized asphalt was purchased from Xinxiang Seventh Chemical Co., Ltd. in Henan Province; barite was purchased from Zhengzhou Xinzheng Meijiu Industrial Co., Ltd.

[0046] Example 1

[0047] In a four-necked flask equipped with a thermometer and a stirrer, 60.5 g of cardanol, 3.9 g of paraformaldehyde, 1.2 g of oxalic acid, and 27.84 g of tetradecyl butyl ether were added and reacted at 120° C. for 3 h. 27.2 g of butane sultone was then added to the mixture and reacted at 140° C. for 5 h. The mixture was cooled to room temperature to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0048] Example 2

[0049] In a four-necked flask equipped with a thermometer and a stirrer, 60.5 g of cardanol, 3.9 g of paraformaldehyde, 1.2 g of oxalic acid, and 26.92 g of tetradecyl butyl ether were added and reacted at 120° C. for 3 h. 24.43 g of propane sultone was then added to the mixture and reacted at 140° C. for 5 h. The mixture was cooled to room temperature to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0050] Example 3

[0051] In a four-necked flask equipped with a thermometer and a stirrer, 60.5 g of cardanol, 3.3 g of paraformaldehyde, 0.61 g of oxalic acid, and 27.84 g of dodecyl methyl ether were added and reacted at 120° C. for 3 h. 27.2 g of butane sultone was then added to the mixture and reacted at 140° C. for 5 h. The mixture was cooled to room temperature to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0052] Example 4

[0053] In a four-necked flask equipped with a thermometer and a stirrer, 60.5 g of cardanol, 3.9 g of paraformaldehyde, 1.2 g of oxalic acid, and 27.84 g of tetradecyl butyl ether were added and reacted at 110° C. for 4 h. 27.2 g of butane sultone was then added to the mixture and reacted at 135° C. for 5 h. The mixture was cooled to room temperature to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0054] Example 5

[0055] In a four-necked flask equipped with a thermometer and a stirrer, 60.5 g of cardanol, 3.9 g of paraformaldehyde, 1.2 g of oxalic acid, and 27.84 g of tetradecyl butyl ether were added and reacted at 120° C. for 2 h. 27.2 g of butane sultone was then added to the mixture and reacted at 145° C. for 4 h. The mixture was cooled to room temperature to obtain a biomass synthetic-based wetting agent for drilling fluid.

[0056] Example 6

[0057] Biomass base liquid: 80% (volume fraction), 20% calcium chloride aqueous solution: 20% (volume fraction)

[0058] Based on the total volume of the biomass base fluid and the calcium chloride aqueous solution: 2% mass volume ratio of organic soil, 6% mass volume ratio of emulsifier, 1% mass volume ratio of the wetting agent prepared in Example 1, and 4% mass volume ratio of oxidized asphalt were added to the base fluid in sequence and stirred at high speed for 10 minutes, then the calcium chloride aqueous solution was added and stirred at high speed for 5 minutes, then 3% mass volume ratio of calcium oxide was added and stirred at high speed for 2 minutes, and then barite was added to adjust the drilling fluid density to 2.1 g / cm 3 , stir at high speed for 20 minutes to obtain drilling fluid.

[0059] Example 7

[0060] The drilling fluid was obtained according to the preparation method of Example 6. The difference from Example 6 was that the volume fraction of the biomass base fluid was 90%, the volume fraction of the calcium chloride aqueous solution was 10%, and the drilling fluid density was 2.5 g / cm 3 .

[0061] Example 8

[0062] A drilling fluid was obtained according to the preparation method of Example 6, except that the wetting agent was the wetting agent prepared in Example 2 at a mass volume ratio of 1%.

[0063] Example 9

[0064] The drilling fluid was obtained according to the preparation method of Example 6, except that the wetting agent was the wetting agent prepared in Example 3 at a mass volume ratio of 1%.

[0065] Example 10

[0066] The drilling fluid was obtained according to the preparation method of Example 6, except that the wetting agent was the wetting agent prepared in Example 4 at a mass volume ratio of 1%.

[0067] Example 11

[0068] The drilling fluid was obtained according to the preparation method of Example 6, except that the wetting agent was the wetting agent prepared in Example 5 at a mass volume ratio of 1%.

[0069] Example 12

[0070] Drilling fluid was obtained according to the preparation method of Example 6, except that the base fluid was diesel.

[0071] Example 13

[0072] Drilling fluid was obtained according to the preparation method of Example 6, except that the base fluid was 3# white oil.

[0073] Comparative Example 1

[0074] A drilling fluid was obtained according to the preparation method of Example 6, except that no wetting agent was added.

[0075] Comparative Example 2

[0076] A drilling fluid was obtained according to the preparation method of Example 6, except that the wetting agent was 1% by mass volume of HIWET wetting agent.

[0077] Comparative Example 3

[0078] A drilling fluid was obtained according to the preparation method of Example 6, except that the wetting agent was 1% by mass by volume HFWE wetting agent.

[0079] Performance testing

[0080] The test method for the wettability of the samples prepared in Examples 1 to 5 of the present invention is as follows: 150 mL of biomass base liquid was added to a stirring cup, 1 g of wetting agent was added, and the mixture was stirred at 11000 rpm for 20 min. Then, 10 g of barite was added and stirred at 11000 rpm for 20 min. The mixture was poured into a 250 mL graduated cylinder and allowed to stand for 1 h. The wettability was calculated based on the volume V (mL) of the clear oil separated from the upper layer. The calculation formula is as follows:

[0081]

[0082] LD of the wetting agents prepared in Examples 1 to 5 of the present invention 50 The values are determined according to the standards "Test Methods for Acute Oral Toxicity of Chemicals" (GB / T 21603-2008) and "Test Methods for Acute Inhalation Toxicity of Chemicals" (GB / T21605-2008). Cr The values are measured according to the standard "Technical Requirements for Environmental Protection of Water-Soluble Oilfield Chemicals" (SY / T 6787-2010).

[0083] The test results are as follows:

[0084]

[0085]

[0086] It can be seen that the biomass synthetic-based drilling fluid wetting agent prepared in the embodiment of the present invention has a high wetting rate, is non-toxic, and has high biodegradability compared to other wetting agents.

[0087] The performance of the drilling fluids prepared in Examples 6 to 13 of the present invention and Comparative Examples 1 to 3 was tested at 65° C. in accordance with the national standard GB / T 16783.2-2012 "Field Testing of Drilling Fluids in the Petroleum and Natural Gas Industry - Part 2: Oil-Based Drilling Fluids". The test results are as follows:

[0088]

[0089] In the table, AV is the apparent viscosity, PV is the plastic viscosity, YP is the dynamic shear force, Gel is the initial and final shear force, ES is the emulsion breaking voltage, HTHP is the high temperature and high pressure fluid loss, Δρ 24h It is the density difference after standing for 24 hours.

[0090] It can be seen that the drilling fluid without wetting agent in Example 1 has higher viscosity, lower demulsification voltage, and poor sedimentation stability, and the 24h density difference reaches 0.1g / cm 3 The wetting agent prepared by the present invention has a better wetting effect than other wetting agents. The density difference of the drilling fluid after standing for 24 hours at the same density is 0.01-0.02 g·cm -3 , effectively avoiding downhole complications caused by solid phase sedimentation in drilling fluids during construction. Furthermore, the strong adsorption effect of the wetting agent prepared by the present invention allows for more uniform solid phase dispersion, resulting in lower viscosity and shear force in the prepared drilling fluid, facilitating on-site construction. Comparing the results of Examples 6, 12, and 13, the wetting agent prepared by the present invention is compatible with diesel, white oil, and biomass-synthesized base fluids, meeting the needs of diverse sites.

[0091] The biomass synthetic-based gemini wetting agent for drilling fluid provided by the present invention has a main raw material extracted from cashew nut shells and is obtained by modifying natural materials. It has the characteristics of wide raw material sources, excellent environmental protection and good biodegradability.

[0092] Although the present invention has been described and illustrated with reference to specific embodiments of the present invention, these descriptions and illustrations do not limit the present invention. It will be clearly understood by those skilled in the art that, without departing from the true spirit and scope of the present invention as defined by the appended claims, various changes may be made to make specific circumstances, materials, compositions of matter, substances, methods or processes suitable for the object, spirit and scope of the present application. All such modifications are intended to be within the scope of the appended claims. Although the methods disclosed herein have been described with reference to specific operations performed in a specific order, it will be understood that these operations may be combined, subdivided or reordered to form equivalent methods without departing from the teachings of the present invention. Therefore, unless otherwise indicated herein, the order and grouping of operations are not limitations of the present application.

Claims

1. A method for preparing a biomass synthetic-based wetting agent for drilling fluid, comprising: Carbomer, paraformaldehyde, a catalyst and a solvent are subjected to a first reaction to obtain a reaction product; the catalyst is selected from one or more of hydrochloric acid, oxalic acid and succinic acid; the solvent is selected from one or more of dodecyl methyl ether, lauryl amyl ether and tetradecyl butyl ether; The reaction product and sultone are subjected to a second reaction at a temperature of 135 to 145° C. to obtain a biomass-synthesized wetting agent for drilling fluid; the molar ratio of the cardanol, paraformaldehyde and sultone is 2.0:(1.1 to 1.4):2.

0.

2. The method according to claim 1, characterized in that The mass of the catalyst is 1 to 3% of the mass of cardanol; The amount of the solvent used is 30-50% of the total mass of cardanol, paraformaldehyde, catalyst and sultone.

3. The method according to claim 1, characterized in that The sultone is selected from one or more of propane sultone and butane sultone.

4. The method according to claim 1, wherein The first reaction temperature is 110-120°C.

5. A drilling fluid comprising: A biomass synthetic-based wetting agent for drilling fluid obtained by the preparation method according to claim 1 or 2.

6. The drilling fluid according to claim 5, characterized in that The drilling fluid is selected from one or more of biomass synthetic-based drilling fluid, mineral oil-based drilling fluid and gas-to-liquid-based drilling fluid.

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