Sulfonate fluid loss reducer for drilling fluid and preparation method thereof

Abstract

The present invention relates to the technical field of oilfield development, and discloses a sulfonate fluid loss reducer for drilling fluid and a preparation method thereof, comprising the steps of: adding dehydroabietylamine to a solvent, adding epoxybutene and a catalyst, and reacting to obtain a modifier; adding 2-acrylamido-2-methylpropanesulfonic acid to deionized water, adjusting the pH to 7-9, adding sodium styrenesulfonate and acrylamide, and stirring to obtain an aqueous phase; adding an emulsifier to the aqueous phase and stirring to obtain a pre-emulsion; under nitrogen conditions, adding an initiator and a modifier to the pre-emulsion, reacting at 30-40°C for 30-60min, and then heating to 70-90°C for 2-4h to obtain a sulfonate fluid loss reducer for drilling fluid. The present invention prepares a modifier using a natural product derivative, dehydroabietylamine, as a raw material, for improving the temperature resistance of the fluid loss reducer and reducing the fluid loss.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield development, and in particular to a sulfonate fluid loss reducer for drilling fluid and a preparation method thereof. Background Art

[0002] Fluid loss additives are chemical agents used during oilfield drilling to effectively reduce fluid loss. With the continuous advancement of exploration technology, more and more deep and ultra-deep wells are emerging, which places higher demands on the high-temperature resistance of fluid loss additives used in drilling fluids.

[0003] Patent publication number CN118406183A discloses a high-temperature-resistant fluid loss reducer for oil-based drilling fluids. The fluid loss reducer is made from the following raw materials: acrylic acid, acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, 3-((2-(acryloyloxy)ethyl)dimethylammonium)propane-1-sulfonic acid inner salt, 3-acetyl-N-vinylpyrrolidone, N,N'-methylenebisacrylamide, an inorganic base, an initiator, and water. While the resulting fluid loss reducer exhibits improved high-temperature resistance, its performance still does not fully meet current requirements. Therefore, developing fluid loss reducers with improved high-temperature resistance is of great significance. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the disadvantage of poor temperature resistance of the fluid loss reducer in the prior art, thereby providing a sulfonate fluid loss reducer for drilling fluid and a preparation method thereof, wherein the obtained fluid loss reducer has good temperature resistance and low fluid loss.

[0005] In order to solve the above technical problems, a method for preparing a sulfonate fluid loss reducer for drilling fluid comprises the following steps:

[0006] (1) Adding dehydroabietylamine to a solvent, adding epoxybutene and a catalyst, and reacting to obtain a modifier;

[0007] (2) Add 2-acrylamido-2-methylpropanesulfonic acid to deionized water, adjust the pH to 7-9, add sodium styrenesulfonate and acrylamide, and stir to obtain an aqueous phase;

[0008] (3) adding the emulsifier to the aqueous phase and stirring to obtain a pre-emulsion;

[0009] (4) Under nitrogen conditions, an initiator and a modifier are added to the pre-emulsion, and the mixture is reacted at 30-40°C for 30-60 minutes, and then the temperature is raised to 70-90°C and the mixture is reacted for 2-4 hours to obtain a sulfonate fluid loss reducer for drilling fluid;

[0010] The preparation reaction process formula of the modifier is:

[0011] ;

[0012] The catalyst is at least one of zinc or nano zinc oxide;

[0013] The emulsifier is at least one of nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether or fatty alcohol polyoxyethylene ether;

[0014] The initiator is a composite initiator of potassium persulfate and sodium bisulfite;

[0015] The mass ratio of the 2-acrylamido-2-methylpropanesulfonic acid, sodium styrenesulfonate, acrylamide, and modifier is 40-50:10-20:20-30:10-20.

[0016] Preferably, the solvent in step (1) is N,N-dimethylformamide.

[0017] Preferably, the molar ratio of dehydroabietylamine to epoxybutene in step (1) is 1:2-1:3, the reaction temperature is 70-100° C., and the reaction time is 4-8 h.

[0018] Preferably, the mass ratio of the dehydroabietylamine to the catalyst is 100:1-2, the mass ratio of the 2-acrylamido-2-methylpropanesulfonic acid to the emulsifier is 4-5:1, and the mass ratio of the modifier to the initiator is 6-15:1.

[0019] Preferably, the mass ratio of potassium persulfate to sodium bisulfite is 1:2 to 2:1.

[0020] Preferably, the mass ratio of the emulsifier to deionized water is 10:120-150.

[0021] Preferably, the stirring time in step (2) is 20-30 min and the temperature is 25-30°C.

[0022] Preferably, the stirring time in step (3) is 10-20 min and the temperature is 25-30°C.

[0023] The present invention also provides a sulfonate fluid loss reducer for drilling fluid, which is prepared by adopting the preparation method.

[0024] The technical solution of the present invention has the following advantages:

[0025] The present invention provides a sulfonate fluid loss reducer for drilling fluid and a preparation method thereof. The modifier is prepared using a natural product derivative, dehydroabietylamine, as a raw material, and is used to improve the temperature resistance of the fluid loss reducer and reduce the fluid loss amount. The obtained modifier molecule contains a rigid ring structure, which can enhance its temperature resistance. In addition, the modifier molecule also contains two double bond structures, which can not only polymerize with other components but also act as a cross-linking agent to further promote polymerization between compounds, thereby enhancing the temperature resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is the FT-IR graph of the modifier of the present invention. DETAILED DESCRIPTION

[0027] The following examples are provided for a better understanding of the present invention and are not intended to limit the best mode of implementation. They do not limit the content and scope of protection of the present invention. Any product identical or similar to the present invention obtained by anyone under the guidance of the present invention or by combining the features of the present invention with other prior arts shall fall within the scope of protection of the present invention.

[0028] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in this field can be used. If the manufacturer of the reagents or instruments is not specified, they are all commercially available conventional reagents.

[0029] FT-IR (Fourier transform infrared spectroscopy) was performed using a Nicolet IS50 infrared spectrometer.

[0030] Example 1

[0031] A method for preparing a sulfonate fluid loss reducer for drilling fluid comprises the following steps:

[0032] (1) Add 28.5 g of dehydroabietylamine to 300 mL of N,N-dimethylformamide, add 15.6 g of epoxybutene and 0.5 g of nano zinc oxide, and react at 80 °C for 6 h to obtain a modifier;

[0033] (2) Add 45 g of 2-acrylamido-2-methylpropanesulfonic acid to 130 g of deionized water, add 40% sodium hydroxide to adjust the pH to 8, then add 15 g of sodium styrenesulfonate and 25 g of acrylamide, and stir at 25 °C for 30 min to obtain an aqueous phase;

[0034] (3) Add 10 g of fatty alcohol polyoxyethylene ether to the aqueous phase and stir at 25 °C for 20 min to obtain a pre-emulsion;

[0035] (4) Under nitrogen conditions, 0.5 g of sodium bisulfite, 1 g of potassium persulfate, and 20 g of modifier were added to the pre-emulsion, and the mixture was reacted at 35 °C for 40 min. The mixture was then heated to 80 °C and reacted for 3 h. The product was dried at 65 °C and crushed to obtain a sulfonate fluid loss reducer for drilling fluid.

[0036] The FT-IR spectrum of the obtained modifier is as follows: Figure 1 As shown, from Figure 1 It can be seen that at 3314.03cm -1 The characteristic absorption peak of hydroxyl group appears at 3079.92 cm -1 The characteristic absorption peak of the terminal =CH appears at 1623.16cm -1 The characteristic absorption peak of carbon-carbon double bond appears at .

[0037] Example 2

[0038] A method for preparing a sulfonate fluid loss reducer for drilling fluid comprises the following steps:

[0039] (1) Add 28.5 g of dehydroabietylamine to 300 mL of N,N-dimethylformamide, add 21.0 g of epoxybutene and 0.5 g of nano zinc oxide, and react at 100 °C for 8 h to obtain a modifier;

[0040] (2) Add 50 g of 2-acrylamido-2-methylpropanesulfonic acid to 150 g of deionized water, add 40% sodium hydroxide to adjust the pH to 9, then add 20 g of sodium styrenesulfonate and 30 g of acrylamide, and stir at 30 °C for 30 min to obtain an aqueous phase;

[0041] (3) Add 10 g of fatty alcohol polyoxyethylene ether to the aqueous phase and stir at 30 °C for 20 min to obtain a pre-emulsion;

[0042] (4) Under nitrogen conditions, 0.5 g of sodium bisulfite, 0.5 g of potassium persulfate, and 15 g of modifier were added to the pre-emulsion, and the mixture was reacted at 40 °C for 60 min. The mixture was then heated to 90 °C and reacted for 4 h. The product was dried at 65 °C and crushed to obtain a sulfonate fluid loss reducer for drilling fluid.

[0043] Example 3

[0044] A method for preparing a sulfonate fluid loss reducer for drilling fluid comprises the following steps:

[0045] (1) Add 28.5 g of dehydroabietylamine to 300 mL of N,N-dimethylformamide, add 14.0 g of epoxybutene and 0.5 g of zinc, and react at 70 °C for 4 h to obtain a modifier;

[0046] (2) Add 40 g of 2-acrylamido-2-methylpropanesulfonic acid to 120 g of deionized water, add 40% sodium hydroxide to adjust the pH to 7, then add 10 g of sodium styrene sulfonate and 20 g of acrylamide, and stir at 30 °C for 20 min to obtain an aqueous phase;

[0047] (3) Add 10 g of nonylphenol polyoxyethylene ether to the aqueous phase and stir at 30 °C for 20 min to obtain a pre-emulsion;

[0048] (4) Under nitrogen conditions, 1.0 g of sodium bisulfite, 0.5 g of potassium persulfate, and 10 g of modifier were added to the pre-emulsion, and the mixture was reacted at 30 °C for 60 min. The mixture was then heated to 70 °C and reacted for 2 h. The product was dried at 65 °C and crushed to obtain a sulfonate fluid loss reducer for drilling fluid.

[0049] Comparative Example 1

[0050] A method for preparing a sulfonate fluid loss reducer for drilling fluid comprises the following steps:

[0051] (2) Add 45 g of 2-acrylamido-2-methylpropanesulfonic acid to 130 g of deionized water, add 40% sodium hydroxide to adjust the pH to 8, then add 15 g of sodium styrenesulfonate and 25 g of acrylamide, and stir at 25 °C for 30 min to obtain an aqueous phase;

[0052] (2) Add 10 g of fatty alcohol polyoxyethylene ether to the aqueous phase and stir at 25°C for 20 min to obtain a pre-emulsion;

[0053] (3) Under nitrogen conditions, 0.5 g of sodium bisulfite, 1 g of potassium persulfate, and 20 g of cross-linking agent N,N'-methylenebisacrylamide were added to the pre-emulsion, and the mixture was reacted at 35 °C for 40 min. The mixture was then heated to 80 °C and reacted for 3 h. The product was dried at 65 °C and crushed to obtain a sulfonate fluid loss reducer for drilling fluid.

[0054] The white oil-based drilling fluid formula includes: 240 mL of 5# white oil, 6 g of organic clay, 60 mL of a 20% CaCl₂ solution, 12 g of a primary emulsifier, 4 g of a secondary emulsifier, and 12 g of a fluid loss additive. The samples prepared in the Examples were tested according to GB / T 16783.2-2012, Field Testing of Drilling Fluids for the Petroleum and Natural Gas Industry, Part 2: Oil-Based Drilling Fluids. The fluid loss at room temperature was measured before aging and after aging for 16 hours at 150°C, 200°C, and 230°C. The fluid loss was also measured at 150°C and 3.5 MPa under high-temperature and high-pressure conditions.

[0055] Table 1 Performance indicators of different embodiments and comparative examples

[0056]

[0057] As can be seen from Table 1, the present application uses the natural product derivative dehydroabietylamine as a raw material to prepare a modifier for improving the temperature resistance of the fluid loss reducer and reducing the fluid loss. The obtained modifier molecule contains a rigid ring structure, which can enhance its temperature resistance. In addition, the modifier molecule also contains two double bond structures, which can not only polymerize with other components, but also act as a cross-linking agent to further promote polymerization between compounds, thereby enhancing the temperature resistance.

[0058] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for preparing a sulfonate fluid loss reducer for drilling fluid, characterized in that: The steps include: (1) adding dehydroabietylamine to a solvent, adding epoxybutene and a catalyst, and reacting to obtain a modifier; (2) adding 2-acrylamido-2-methylpropanesulfonic acid to deionized water, adjusting the pH to 7-9, adding sodium styrenesulfonate and acrylamide, and stirring to obtain an aqueous phase; (3) adding an emulsifier to the aqueous phase and stirring to obtain a pre-emulsion; (4) adding an initiator and a modifier to the pre-emulsion under nitrogen conditions, reacting at 30-40° C. for 30-60 minutes, then heating to 70-90° C. and reacting for 2-4 hours to obtain a sulfonate fluid loss reducer for drilling fluid; The preparation reaction process formula of the modifier is: The catalyst is at least one of zinc or nano zinc oxide; The emulsifier is at least one of nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether or fatty alcohol polyoxyethylene ether; The initiator is a composite initiator of potassium persulfate and sodium bisulfite; The mass ratio of the 2-acrylamido-2-methylpropanesulfonic acid, sodium styrenesulfonate, acrylamide, and modifier is 40-50:10-20:20-30:10-20; The solvent in step (1) is N,N-dimethylformamide; In step (1), the molar ratio of dehydroabietylamine to epoxybutene is 1:2-1:3, the reaction temperature is 70-100° C., and the reaction time is 4-8 h.

2. The method for preparing the sulfonate fluid loss reducer for drilling fluid according to claim 1, wherein: The mass ratio of the dehydroabietylamine to the catalyst is 100:1-2, the mass ratio of the 2-acrylamido-2-methylpropanesulfonic acid to the emulsifier is 4-5:1, and the mass ratio of the modifier to the initiator is 6-15:

1.

3. The method for preparing the sulfonate fluid loss reducer for drilling fluid according to claim 1, wherein: The mass ratio of the potassium persulfate to the sodium bisulfite is 1:2 to 2:

1.

4. The method for preparing the sulfonate fluid loss reducer for drilling fluid according to claim 1, wherein: The mass ratio of the emulsifier to deionized water is 10:120-150.

5. The method for preparing the sulfonate fluid loss reducer for drilling fluid according to claim 1, wherein: The stirring time in step (2) is 20 to 30 minutes, and the temperature is 25 to 30°C.

6. The method for preparing the sulfonate fluid loss reducer for drilling fluid according to claim 1, wherein: The stirring time in step (3) is 10 to 20 minutes, and the temperature is 25 to 30°C.

7. A sulfonate fluid loss reducer for drilling fluid, characterized in that: The preparation method is described in any one of claims 1 to 6.

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