Drilling fluid composition, use thereof, and method for preparing drilling fluid base solution

Abstract

The present invention relates to the technical field of drilling fluids; disclosed are a drilling fluid composition, a use thereof, and a method for preparing a drilling fluid base solution. The drilling fluid composition comprises a silylamino alkyl glycoside and a cationic chitosan; in addition, the composition has an extreme pressure lubrication coefficient of 0.001-0.05 and a compression index of 1.3-5. The drilling fluid composition provided by the present invention comprises both the silylamino alkyl glycoside and the cationic chitosan, and the two have a good synergistic effect, so that the obtained base solution and drilling fluid have good performance in inhibiting collapse, consolidating wall cementation, lubricating and preventing sticking, plugging to reducing filtration loss, etc., and can meet the performance requirements of preparing drilling fluids.

Description

A drilling fluid composition and its application and a method for preparing a drilling fluid base fluid

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Chinese patent application 202310962942.7 filed on August 1, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to the technical field of drilling fluid, and in particular to a drilling fluid composition and application thereof, and a method for preparing a drilling fluid base fluid. Background Art

[0004] During oil and gas drilling, when drilling into highly active shale and mudstone-bearing formations prone to collapse, such as those with high clay mineral content, conventional water-based drilling fluids cannot effectively inhibit the hydration, expansion, and dispersion of these formations. While highly inhibited water-based drilling fluids offer better collapse prevention, are low-cost, and are environmentally friendly, their performance is still not comparable to that of oil-based drilling fluids. Furthermore, when drilling into highly active shale and other prone to collapse, the use of oil-based drilling fluids still has numerous drawbacks, including high preparation costs, interference with logging operations, significant losses during well leakage, and high pressure in the environmental post-processing of drill cuttings. These shortcomings limit the wider application of oil-based drilling fluids. Therefore, in this context, the search for a near-oil-based drilling fluid with a similar mechanism of action, comparable performance, and environmentally friendly performance has become an urgent need in the field. Near-oil-based drilling fluid is a green, safe and efficient water-based drilling fluid with performance comparable to that of oil-based drilling fluid. It belongs to the category of water-based drilling fluid, not an oil-based drilling fluid.

[0005] For near-oil-based drilling fluids, the most critical factor is the base fluid used to formulate them. These base fluids are required to exhibit excellent performance, including anti-collapse suppression, wall reinforcement, lubrication and anti-sticking, plugging and filtration reduction, and environmentally friendly properties, meeting the performance requirements for near-oil-based drilling fluids. The development of base fluid products for near-oil-based drilling fluids will significantly promote the research and application of near-oil-based drilling fluids, enabling green, safe, and efficient drilling in highly reactive shale and mudstone-containing formations prone to collapse, ultimately achieving the technical goal of "water replacing oil."

[0006] Summary of the Invention

[0007] In view of this, the object of the present invention is to provide a drilling fluid composition, its application and a method for preparing a drilling fluid base fluid. The drilling fluid composition provided by the present invention has good properties such as inhibiting collapse, solid wall bonding, lubricating and preventing sticking, plugging and reducing filtration loss, is green and environmentally friendly, and can meet the performance requirements of preparing drilling fluid.

[0008] According to a first aspect of the present invention, a drilling fluid composition is provided. The composition contains silanol alkyl glycoside and cationic chitosan, and has an extreme pressure lubrication coefficient of 0.001-0.05 and a compression index of 1.3-5.

[0009] According to a second aspect of the present invention, the present invention provides use of the above composition in drilling fluid.

[0010] According to a third aspect of the present invention, the present invention provides a drilling fluid containing the above composition.

[0011] According to a fourth aspect of the present invention, the present invention provides a method for preparing a drilling fluid base fluid, the method comprising:

[0012] In parts by mass, 0-15 parts, preferably 3-12 parts, of a multi-branched polyetheramine, 0-45 parts, preferably 10-40 parts, of aminocyclodextrin, 1-10 parts, preferably 3-7 parts, of cationic chitosan, 40-60 parts, preferably 42-58 parts, of silanylaminoalkyl glycoside, and 0-30 parts, preferably 18-24 parts, of sulfonylaminoglyceryl glycoside are stirred and uniformly mixed at 60-85° C. under the protection of an inert gas.

[0013] The drilling fluid composition provided by the present invention contains both silanol aminoalkyl glycoside and cationic chitosan, which have a good synergistic effect, so that the resulting base fluid and drilling fluid have good performance in inhibiting and preventing collapse, solidifying wall cementation, lubricating and preventing sticking, plugging and reducing fluid loss, etc., which can meet the performance requirements of preparing drilling fluid. According to a preferred embodiment of the present invention, when the base fluid simultaneously contains a certain ratio of multi-branched polyetheramine, aminocyclodextrin, cationic chitosan, silanol aminoalkyl glycoside, and sulfonylaminoglycerol glycoside, the performance of the resulting base fluid and drilling fluid in inhibiting and preventing collapse, solidifying wall cementation, lubricating and preventing sticking, plugging and reducing fluid loss, etc. is further improved. Moreover, the above-mentioned base fluid is green and environmentally friendly, has strong compatibility, and can meet the performance requirements of preparing drilling fluid. The drilling fluid composition provided by the present invention enables the prepared base fluid and drilling fluid to simultaneously possess the properties of oil-based drilling fluid such as anti-collapse, lubrication and anti-sticking, and plugging and filtration loss reduction, as well as the wall-solidifying and cementing properties and environmental protection properties of water-based drilling fluid. The present invention is a drilling fluid composition with excellent performance. The obtained drilling fluid is a near-oil-based drilling fluid between water-based drilling fluid and oil-based drilling fluid, and combines the advantages of both water-based drilling fluid and oil-based drilling fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figures 1 to 5 are infrared spectra of multi-branched polyetheramine, aminocyclodextrin, cationic chitosan, silanylaminoalkyl glycoside, and sulfonylaminoglycerol glycoside, respectively.

[0015] FIG6 is a scanning electron microscope photograph of a medium-pressure filter cake of a 4 wt% sodium bentonite-based slurry.

[0016] FIG7 is a scanning electron microscope photograph of the medium-pressure filter cake after adding 2% of the sample of Example 1 to 4 wt% sodium bentonite-based slurry. DETAILED DESCRIPTION

[0017] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0018] The drilling fluid composition provided by the present invention contains silanol alkyl glycoside and cationic chitosan, and the composition has an extreme pressure lubrication coefficient of 0.001-0.05 and a compressive index of 1.3-5. Preferably, the extreme pressure lubrication coefficient of the composition is 0.005-0.025 and the compressive index is 1.5-3.

[0019] The drilling fluid composition provided by the present invention contains both silanol alkyl glycoside and cationic chitosan, has a low extreme pressure lubrication coefficient, good lubrication and anti-sticking properties, good plugging and fluid loss reduction properties, and a compression index within the range of 1.3-5, preferably 1.5-3. Therefore, the compression resistance is good, and the prepared base fluid and drilling fluid have the same performance as oil-based drilling fluid in terms of inhibiting collapse, lubricating and anti-sticking, plugging and fluid loss reduction.

[0020] The infrared spectrum can be used to prove that the composition contains silanol alkyl glycoside and cationic chitosan. For example, there is a 2830-2950cm -1 The stretching vibration peak of the CH bond in methyl and methylene is 3380 cm -1 Nearby is the stretching vibration peak of the OH bond, 1164 cm -1 Nearby is the stretching vibration peak of COC, which can be confirmed to have a glycoside structure; 1419cm -1 Nearby is the absorption peak of CN bond, 1196cm -1 Nearby is the bending vibration peak of the CN bond, which can be used to determine the structure containing amino groups; 1689cm -1 Nearby, 1280cm -1 The characteristic peak of amide group is near 1093cm -1 It is the characteristic peak of Si-O. It indicates that amino group, amide group and siloxane group have been introduced into the molecular structure of glycoside, that is, the composition contains silanol alkyl glycoside. -1 The chitosan NH bending vibration absorption peak is located near 1214 cm -1 The COC stretching vibration absorption peak is located near the 1405cm-1 The CN stretching vibration absorption peak is near the modified chitosan, indicating that the modified chitosan has introduced a quaternary ammonium group. In the present invention, the near refers to the instrument and operation error acceptable to those skilled in the art, for example, ±10cm -1 .

[0021] In the present invention, the compressive index refers to the ratio of the compressive strength of the core before and after immersion. Compression index = P1 / P0. In the present invention, compressive strength refers to uniaxial compressive strength. The specific testing method is: place the soaked core column on a compressive strength tester and increase the load along the axis of the core column at a rate of 0.5 MPa per second until the pressure at which the core column fails is the compressive strength. The compressive strength of the original, unimmersed core is recorded as P0, and the compressive strength of the core column measured after immersion in a sample of the drilling fluid composition with a mass concentration of 2.0% at 210°C for 16 hours is recorded as P1.

[0022] In the present invention, the core column is prepared by the following method: 100 g of drilling-grade bentonite that meets the API standard is selected, placed in a drying oven, and dried at 105° C. for 4 hours. After being taken out, it is cooled to room temperature. Then, 25 g of the dried bentonite is weighed, 3 mL of distilled water is added, and the bentonite and distilled water are mixed evenly. The core column is pressed at a pressure of 10 MPa for 5 minutes to make a core column with a diameter of 2.4 cm and a height of 2.6 cm, which is the core column used in the present invention.

[0023] In the present invention, preferably, the compressive index of the raw material silanol amino alkyl glycoside in the drilling fluid composition is 1.2-1.25.

[0024] In the present invention, preferably, the compressive index of the raw material cationic chitosan in the drilling fluid composition is 0.58-0.65.

[0025] In the present invention, preferably, the compression index of the raw material multi-branched polyetheramine in the drilling fluid composition is 0.8-0.9.

[0026] In the present invention, preferably, the compressive index of the raw material sulfaminylglycerol glycoside in the drilling fluid composition is 0.3-0.4.

[0027] In the present invention, preferably, the compression index of the raw material aminocyclodextrin in the drilling fluid composition is 0.85-1.

[0028] The extreme pressure lubrication coefficient calculation formula is:

[0029] In the above formula, K is the extreme pressure lubrication coefficient; X and Y are obtained by the following test methods: immerse the slider in the extreme pressure lubrication instrument in a 2.0% drilling fluid base fluid sample to be tested, adjust the torque wrench value to 16.95 N / m, and operate the instrument for 5 minutes. The value displayed on the instrument is X; immerse the slider in the instrument in clean water, adjust the torque wrench value to 16.95 N / m, and operate the instrument for 5 minutes. The value displayed on the instrument when the slider is immersed in clean water is Y.

[0030] In the present invention, the silanol alkyl glycoside refers to a product in which the hydrogen of one or more hydroxyl groups on the alkyl glycoside structure is replaced by a group containing an amine group (primary amine group, secondary amine group, tertiary amine group) and a siloxane (trialkoxysilane) group.

[0031] According to a preferred embodiment of the present invention, in the present invention, the silanol alkyl glycoside has a structure shown in the following formula I:

[0032] In formula I, R1 is a C1-C14 alkyl group, m is 1-16, and relative to the total amount of silanol alkyl glycoside, the content of X is 25-60 mass %, preferably 35-55 mass %, the content of Y is 30-55 mass %, preferably 40-50 mass %, and the content of Z is 0.2-60 mass %, preferably 0.2-55 mass %;

[0033] X, Y, and Z are each at least one of H, an unsaturated amide residue, an unsaturated siloxane residue, a polyether group, and a polyene polyamine residue, and X, Y, and Z are different;

[0034] Preferably, X, Y, and Z are each at least one of H, a group represented by the following formula I-1), a group represented by the following formula I-2), and a group represented by the following formula I-3, and X, Y, and Z are different;

[0035] Preferably, Y comprises an unsaturated amide residue and an unsaturated siloxane residue;

[0036] In formula I-1), R2 is a C1-C3 alkyl group, n is 1-2, and o is 0-4;

[0037] In formula I-2), R3 is H or a C1-C4 alkyl group, and p is 1-30;

[0038] In formula I-3), R4 is a C1-C4 alkyl group, and q is 1-20;

[0039] Preferably, Y includes a group represented by the above formula I-2) and a group represented by the above formula I-3).

[0040] In the present invention, the silanol alkyl glycoside can be prepared by referring to the method disclosed in CN111320657A. Specifically, the method may include the following steps: 1) reacting an alkyl glycoside with an epoxyhalogenated (such as chloro) alkane compound under the action of an acidic catalyst to obtain a halohydrin alkyl glycoside; 2) reacting the halohydrin alkyl glycoside with an organic amine to obtain an aminoalkyl glycoside; 3) reacting the aminoalkyl glycoside with an acrylamide compound and a vinyltrialkoxysilane under the action of an initiator to obtain a silanol alkyl glycoside.

[0041] The alkyl glycoside may be one or more of methyl glycoside, ethyl glycoside, propyl glycoside, hexyl glycoside, octyl glycoside, decyl glycoside, dodecyl glycoside, and tetradecyl glycoside. In other words, in Formula I, R1 may be a C1-C14 alkyl group such as methyl, ethyl, propyl, hexyl, octyl, decyl, dodecyl, and tetradecyl.

[0042] The epoxyhalogenated (such as chloro) alkane compound may be, for example, one or more of epichlorohydrin, epichlorobutane, and epichloropentane.

[0043] The acrylamide compound may be, for example, acrylamide or methacrylamide.

[0044] The vinyltrialkoxysilane may be, for example, one or more of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, and vinyltributoxysilane.

[0045] The acidic catalyst may be, for example, one or more of hydrofluoric acid, hydrochloric acid, sulfuric acid, phosphoric acid, tartaric acid, oxalic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, and aminosulfonic acid.

[0046] The initiator may be a redox initiator or an azo initiator, for example, selected from ammonium persulfate, potassium persulfate, ceric ammonium nitrate, azobisisobutyronitrile, dimethyl azobisisobutyrate, and azobisisobutylamidine hydrochloride.

[0047] The infrared spectrum of the obtained product can be used to confirm that the obtained polymer is the target polymer. -1 The stretching vibration peak of the CH bond in methyl and methylene is 3380 cm -1 Nearby is the stretching vibration peak of the OH bond, 1164 cm -1 Nearby is the stretching vibration peak of COC, which can be confirmed to have a glycoside structure; 1419cm -1 Nearby is the absorption peak of CN bond, 1196cm -1 The peak of the bending vibration of the CN bond can be used to determine the structure containing an amino group; 1689cm -1Nearby, 1280cm -1 The characteristic peak of amide group is near 1093cm -1 Nearby is the characteristic peak of Si-O, indicating that amino groups, amide groups, and siloxane groups have been introduced into the glycoside molecular structure.

[0048] In the present invention, the cationic chitosan refers to chitosan in which one or more hydroxyl groups are replaced by residues containing cationic groups, wherein the cationic groups are preferably quaternary ammonium cations, and the anions compatible with the quaternary ammonium cations may be chloride ions, bromide ions, iodide ions, or nitrate ions. According to a preferred embodiment of the present invention, the cationic chitosan has a structure shown in the following formula II:

[0049] In formula II, R is an alkyl group having 1 to 3 carbon atoms, m is 1200 to 3100, and n is 1 to 2.

[0050] In the present invention, cationic chitosan can be prepared by referring to the method disclosed in CN106432537A. Specifically, the method can include the following steps: 1) reacting a mixture containing chitosan, a cosolvent such as a urea compound, an alkaline compound and water with an epoxyhalogenated (such as chloro) alkane compound to obtain an intermediate product; 2) reacting the intermediate product with an alkaline compound and a tertiary amine hydrochloride to obtain cationic chitosan.

[0051] The epoxyhalogenated (such as chloro) alkane compound may be, for example, one or more of epichlorohydrin, 1,2-epoxychlorobutane, and epichloropentane.

[0052] The alkaline compound may be, for example, sodium hydroxide and / or potassium hydroxide.

[0053] The tertiary amine hydrochloride may be, for example, one or more of trimethylamine hydrochloride, triethylamine hydrochloride, and tripropylamine hydrochloride.

[0054] The urea compound may be, for example, one or more of urea, thiourea, and urea phosphate.

[0055] The obtained polymer can be confirmed to be the target polymer by the infrared spectrum of the obtained product. -1 The chitosan NH bending vibration absorption peak is located near 1214 cm -1 The COC stretching vibration absorption peak is located near the 1405cm -1 Nearby is the CN stretching vibration absorption peak, indicating that the modified chitosan has introduced quaternary ammonium groups.

[0056] According to a preferred embodiment of the present invention, the composition further contains multi-branched polyetheramine and sulfonylaminoglycerol glycoside. The composition of this preferred embodiment can further improve the inhibition and lubricity of the drilling fluid.

[0057] Preferably, based on the total amount of the composition, the content of the multi-branched polyetheramine is 1-15 mass %, preferably 3-12 mass %, the content of the silanol alkyl glycoside is 40-90 mass %, preferably 40-58 mass %, the content of the sulfaminyl glyceryl glycoside is 5-30 mass %, preferably 15-25 mass %, and the content of the cationic chitosan is 1-11 mass %, preferably 3-7 mass %.

[0058] In the present invention, the multi-branched polyetheramine refers to a molecule containing multiple amine groups (primary, secondary, and tertiary), and preferably, some or all of the multiple amine groups (primary, secondary, and tertiary) are distributed in a comb-like pattern. Preferably, at least two hydroxyl groups in the glycerol are replaced by amine-containing groups, such as amine-containing segments having 2 to 30 carbon atoms. Preferably, the multi-branched polyetheramine has a structure shown in Formula III,

[0059] Preferably, in formula III, m is 1-16, n is 1-2, and o is 0-4.

[0060] The multi-branched polyetheramine can be prepared by referring to the method disclosed in CN106432708A. For example, glycerol, a glycol compound, water and an acidic catalyst are reacted (preferably under stirring conditions) to obtain an intermediate product, wherein the glycol compound includes ethylene glycol or polyethylene glycol; the intermediate product is reacted with a chloroepoxide, an alkaline compound and an organic amine to obtain a multi-branched polyetheramine; the chloroepoxide includes epichlorohydrin or 1,2-epoxychlorobutane, and the organic amine includes ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or pentaethylenehexamine. Preferably, the temperature of the reaction of glycerol, glycol compound, water and acidic catalyst is 90°C-140°C, preferably 100°C-120°C; and the reaction time is 2 hours-4 hours, preferably 2.5 hours-3.5 hours. In an embodiment of the present invention, glycerol, glycol compound, water and acidic catalyst can be reacted under stirring conditions. After obtaining the intermediate product, the present invention reacts the intermediate product with a chloroepoxide, a basic compound, and an organic amine to obtain a multi-branched polyetheramine. In an embodiment of the present invention, the reaction temperature of the intermediate product with the chloroepoxide, the basic compound, and the organic amine is 40° C. to 60° C., preferably 45° C. to 55° C., and the reaction time is 0.5 to 2 hours, preferably 1 to 1.5 hours.

[0061] Preferably, the number average molecular weight of the polyethylene glycol is 400-800, preferably 500-700, and further preferably 550-650.

[0062] Preferably, the acidic catalyst may be hydrochloric acid, sulfuric acid, phosphoric acid, tartaric acid, oxalic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, aminosulfonic acid or phosphotungstic acid.

[0063] Preferably, the chloroepoxide is epichlorohydrin or 1,2-epoxychlorobutane.

[0064] Preferably, the alkaline compound is one or more of sodium hydroxide, potassium hydroxide, and barium hydroxide.

[0065] Preferably, the organic amine includes ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or pentaethylenehexamine.

[0066] Preferably, the mass ratio of the glycerol, glycol compound, water, acidic catalyst, chloroepoxide, alkaline compound and organic amine is 10:(8-14):(30-60):(0.8-1.5):(5-15):(0.8-1.2):(10-20), further preferably 10:(9-12):(40-50):(1-1.4):(8-12):(0.9-1.1):(12-18), and even more preferably 10:(10-11):(42-48):(1.1-1.3):(10-11):1:(14-16).

[0067] In the present invention, the sulfonylaminoglyceryl glycoside refers to a glyceryl glycoside in which one or more hydroxyl groups are replaced by polyetheramine groups and sulfonated castor oil residues. The polyetheramine group refers to a group containing an amine group (primary amine, secondary amine or tertiary amine) connected to the middle or end of a polyether group. The sulfonated castor oil residue refers to a group corresponding to the esterification reaction between sulfonated castor oil and the hydroxyl group of the glyceryl glycoside. Preferably, the sulfonylaminoglyceryl glycoside has the structure shown in the following formula IV

[0068] In formula IV, m is 1-3, and the content of X is 30-70 mass %, preferably 35-55 mass %, and the content of Y is 20-50 mass %, preferably 25-40 mass % relative to the total amount of sulfaminylglycerol glycoside;

[0069] X and Y are each a group represented by the following formula IV-1) or a group represented by the following formula IV-2), and X and Y are different;

[0070] In formula IV-1), R1 and R2 are each independently selected from an alkyl group having 1 to 3 carbon atoms, n is 1 to 10, o is 1 to 10, and p is 0 to 4.

[0071] Sulfaminoglyceryl glycoside can be prepared by referring to the method disclosed in CN111320659A.

[0072] According to a preferred embodiment of the present invention, the composition further contains aminocyclodextrin. Preferably, the content of aminocyclodextrin is 2-45% by mass, more preferably 10-40% by mass, based on the total amount of the composition. This preferred embodiment of the composition can further improve the inhibitory properties, fluid loss control, and lubricity of the drilling fluid.

[0073] In the present invention, the aminocyclodextrin refers to one or more amino groups on the cyclodextrin, preferably substituted by polyene polyamine groups such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine. Preferably, the aminocyclodextrin has the structure shown in the following formula V:

[0074] In formula V, based on the total amount of aminocyclodextrin, the content of R is 30-70 mass %, preferably 40-55 mass %, and R has the structure shown in the following structural formula i

[0075] In formula i, m is 1-2, and n is 0-4.

[0076] Aminocyclodextrin can be prepared by referring to the method disclosed in CN106432550A.

[0077] The present invention also provides application of the composition in drilling fluid.

[0078] The present invention also provides drilling fluid containing the composition.

[0079] Preferably, the content of the composition is 20-60% by mass based on the total amount of the drilling fluid.

[0080] The present invention also provides a method for preparing a drilling fluid base fluid, the method comprising:

[0081] In parts by mass, 0-15 parts, preferably 3-12 parts, of a multi-branched polyetheramine, 0-45 parts, preferably 10-40 parts, of aminocyclodextrin, 1-10 parts, preferably 3-7 parts, of cationic chitosan, 40-60 parts, preferably 42-58 parts, of silanolaminoalkyl glycoside, and 0-30 parts, preferably 18-24 parts, of sulfonylglycerol glycoside are stirred and mixed uniformly at 60-85° C. under inert gas protection for preferably 2-4 hours.

[0082] Preferably, the inert gas is nitrogen and / or helium.

[0083] In the following examples, multi-branched polyetheramine was prepared by referring to the method disclosed in CN106432708A, aminocyclodextrin was prepared by referring to the method disclosed in CN106432550A, cationic chitosan was prepared by referring to the method disclosed in CN106432537A, silanolaminoalkyl glycoside was prepared by referring to the method disclosed in CN111320657A, and sulfonylaminoglycerol glycoside was prepared by referring to the method disclosed in CN111320659A. The infrared spectra of the polymers used in Example 1 are shown in Figures 1-5 respectively. The infrared spectra of the multi-branched polyetheramine are shown in Figure 1, wherein 1151 cm -1 is the stretching vibration peak of COC, 1050-1100cm -1 The stretching vibration peak of the CO bond in the hydroxyl group can be determined to contain a polyether structure; 1419 cm -1 is the absorption peak of CN bond, 1196cm -1 is the bending vibration peak of the C-N bond, 3380 cm -1 The absorption peak of NH can be used to determine the structure of amine. Based on the above results, the molecular structure of the multi-branched polyetheramine product contains characteristic structures such as hydroxyl groups, ether bonds, CN bonds, and amino groups.

[0084] The infrared spectrum of aminocyclodextrin is shown in Figure 2, where 3357 cm -1 Shows stretching vibrations of -OH and primary amine -NH, 2930 cm -1 The antisymmetric stretching vibration absorption peak of -CH2 is 1458cm -1 The absorption peaks are the deformation vibration of -CH2 and the antisymmetric deformation vibration of -CH3, while 1154 cm -1 The CO stretching vibration absorption peak of β-CD and polymer cavity and COC stretching vibration absorption peak, 707cm -1 It shows the in-plane rocking vibration absorption peak of -CH2.

[0085] The infrared spectrum of cationic chitosan is shown in Figure 3, where the -1 The chitosan NH bending vibration absorption peak is at 1214 cm -1 The COC stretching vibration absorption peak is at 1405 cm, indicating that the modified chitosan has introduced an ether bond through the condensation reaction. -1 The peak at the center is the CN stretching vibration absorption peak, indicating that the modified chitosan has introduced quaternary ammonium groups.

[0086] The infrared spectrum of silanol alkyl glycoside is shown in Figure 4, where 2830-2950cm -1 The stretching vibration peak of the CH bond in methyl and methylene is 3380 cm -1 is the stretching vibration peak of the OH bond, 1164 cm -1The stretching vibration peak of COC indicates the presence of a glycoside structure; 1419 cm -1 is the absorption peak of CN bond, 1196cm -1 The peak of the bending vibration of the CN bond can be used to determine the structure containing an amino group; 1689cm -1 、1280cm -1 is the characteristic peak of amide group; 1093cm -1 It is the characteristic peak of Si-O, indicating that amino groups, amide groups and siloxane groups have been introduced into the molecular structure of glycosides.

[0087] The infrared spectrum of sulfaminylglycerol glycoside is shown in Figure 5, where 3380 cm -1 The stretching vibration peak of the OH bond is 2830-2950cm -1 1151cm is the stretching vibration peak of the CH bond in the methyl and methylene groups, which can be used to determine the presence of a glycoside structure; -1 is the stretching vibration peak of COC, 1050-1100cm -1 The peak of stretching vibration of CO bond in hydroxyl group can be confirmed to contain glyceryl structure; 1419cm -1 is the absorption peak of CN bond, 1196cm -1 The bending vibration peak of the CN bond can be used to determine the structure containing amine; the wave number is 1170 cm -1 , 1000cm -1 It is the characteristic peak of sulfonic acid group, indicating that glyceryl group, amino group and sulfonic acid group have been introduced into the glycoside molecular structure.

[0088] Example 1

[0089] 3 g of multi-branched polyetheramine (prepared according to the method of Example 1 of CN106432708A), 10 g of aminocyclodextrin (prepared according to the method of Example 1 of CN106432550A), 3 g of cationic chitosan (prepared according to the method of Example 1 of CN106432537A), 42 g of silanylaminoalkyl glycoside (prepared according to the method of Example 1 of CN111320657A), and 18 g of sulfonylglycerol glycoside (prepared according to the method of Example 1 of CN111320659A) were mixed uniformly, stirred at 60 ° C for 2 h under nitrogen protection, and obtained a base fluid for preparing drilling fluid.

[0090] Example 2

[0091] 7 g of multi-branched polyetheramine (prepared according to the method of Example 2 of CN106432708A), 20 g of aminocyclodextrin (prepared according to the method of Example 2 of CN106432550A), 5 g of cationic chitosan (prepared according to the method of Example 2 of CN106432537A), 48 g of silanylaminoalkyl glycoside (prepared according to the method of Example 1 of CN111320657A), and 20 g of sulfonylglycerol glycoside (prepared according to the method of Example 2 of CN111320659A) were mixed uniformly, stirred at 70°C for 3 h under helium protection, and obtained a base fluid for preparing drilling fluid.

[0092] Example 3

[0093] 9 g of multi-branched polyetheramine (prepared according to the method of Example 3 of CN106432708A), 30 g of aminocyclodextrin (prepared according to the method of Example 3 of CN106432550A), 6 g of cationic chitosan (prepared according to the method of Example 3 of CN106432537A), 54 g of silanylaminoalkyl glycoside (prepared according to the method of Example 1 of CN111320657A), and 22 g of sulfonylglycerol glycoside (prepared according to the method of Example 3 of CN111320659A) were mixed uniformly, stirred at 80 ° C for 4 h under nitrogen protection, and obtained a base fluid for preparing drilling fluid.

[0094] Example 4

[0095] 12 g of multi-branched polyetheramine (prepared according to the method of Example 4 of CN106432708A), 40 g of aminocyclodextrin (prepared according to the method of Example 4 of CN106432550A), 7 g of cationic chitosan (prepared according to the method of Example 4 of CN106432537A), 58 g of silanylaminoalkyl glycoside (prepared according to the method of Example 1 of CN111320657A), and 24 g of sulfonylglycerol glycoside (prepared according to the method of Example 4 of CN111320659A) were mixed uniformly, stirred at 85 ° C for 4 h under nitrogen protection, and obtained a base fluid for preparing drilling fluid.

[0096] Example 5

[0097] A base fluid for drilling fluid was prepared according to the method of Example 4, except that the multi-branched polyetheramine, aminocyclodextrin and sulfonylaminoglycerol glycoside were not added, and the proportions of other substances remained unchanged to obtain a base fluid for preparing drilling fluid.

[0098] Example 6

[0099] The base fluid of the drilling fluid was prepared according to the method of Example 4, except that aminocyclodextrin and sulfamoylglycerol glycoside were not added, and the proportions of other substances remained unchanged to obtain the base fluid for preparing the drilling fluid.

[0100] Example 7

[0101] A base fluid for preparing drilling fluid was prepared according to the method of Example 4, except that the multi-branched polyetheramine and aminocyclodextrin were not added, and the proportions of other substances remained unchanged, to obtain a base fluid for preparing drilling fluid.

[0102] Comparative Example 1

[0103] The base fluid of the drilling fluid was prepared according to the method of Example 4, except that the above materials were stirred at room temperature in an air environment for 4 hours to obtain a comparative example sample.

[0104] Comparative Example 2

[0105] The base liquid of drilling fluid was prepared according to the method of Example 4, except that cationic chitosan was not added and the proportions of other substances remained unchanged. The above materials were stirred at room temperature in an air environment for 4 hours to obtain the base liquid for preparing drilling fluid.

[0106] Comparative Example 3

[0107] The base liquid of drilling fluid was prepared according to the method of Example 4, except that silanol alkyl glycoside was not added and the proportions of other substances remained unchanged. The above materials were stirred at room temperature in an air environment for 4 hours to obtain the base liquid for preparing drilling fluid.

[0108] Performance testing

[0109] The base fluid prepared in the embodiment of the present invention for preparing drilling fluid was tested for its performance in inhibiting collapse, consolidating the wall, lubricating and preventing sticking, plugging and reducing filtration, and biological toxicity.

[0110] 1) Inhibitory

[0111] ① Shale recovery rate

[0112] The base fluid provided by the present invention was prepared into a base fluid aqueous solution with a mass concentration of 2%, and rolled at 210° C. for 16 hours. The shale primary recovery rate and shale relative recovery rate were tested according to the following method:

[0113] The above-mentioned base liquid aqueous solution with a mass concentration of 2% was stirred at a high speed of 7000 rpm for 5 minutes, and then poured into an aging tank for use; 2.0mm-5.0mm rock chips were taken and dried at 103°C for 4h, and cooled to room temperature; G0g of rock chips were weighed and put into an aging tank and rolled with the above-mentioned base liquid aqueous solution with a mass concentration of 2% at 210°C for 16h, taken out after cooling, and the rock chips were recovered with a 0.42mm pore size sieve, dried at 103°C for 4h, cooled to room temperature, and the mass of the recovered rock chips was weighed and recorded as G1; then the weighed recovered rock chips were put into clean water and rolled at 210°C for 16h, taken out after cooling, and the rock chips were recovered with a 0.42mm pore size sieve, dried at 103°C for 4h, cooled to room temperature, and the mass of the recovered rock chips was weighed and recorded as G2; the shale primary recovery rate, shale secondary recovery rate and shale relative recovery rate were calculated according to the following formula: Shale primary recovery rate = G1 / G0×100%; Secondary recovery rate of shale = G2 / G0×100%; Relative recovery rate of shale = secondary recovery rate of shale / primary recovery rate of shale ×100%;

[0114] ②Relative inhibition rate

[0115] The relative inhibition rate is expressed as follows: 1.75 g of sodium carbonate is added to 350 mL of distilled water. After dissolving, 35 g of calcium bentonite is added and stirred at high speed for 20 minutes to obtain a calcium bentonite-based slurry. The drilling fluid was aged at 210°C for 16 hours, cooled and removed, stirred at high speed for 5 minutes, and the 100r / min reading of the drilling fluid was measured by a six-speed rotary viscometer, and the reading was calculated as φ1 (172); 350mL of distilled water was added, 1.75g ​​of sodium carbonate and 2.0% of the base fluid sample for preparing the drilling fluid (the mass of the base fluid sample is 2.0% of the mass of distilled water), and after fully dissolved, 35g of calcium bentonite was added and stirred at high speed for 20 minutes. The drilling fluid was aged at 210°C for 16 hours, cooled and removed, stirred at high speed for 5 minutes, and the 100r / min reading of the drilling fluid was measured by a six-speed rotary viscometer, and the reading was calculated as φ2. The relative inhibition rate of the base fluid sample for preparing the drilling fluid on the calcium soil base slurry was calculated according to the following formula:

[0116] 2) Compression resistance

[0117] Compressive resistance is expressed as compressive strength and compressive index. Core columns were immersed in samples of the embodiments and comparative examples of the present invention at a mass concentration of 2.0% at 210°C for 16 hours, and the compressive strength P1 of the core columns was tested. The compressive strength of the immersed core columns was tested as follows: the immersed core column was placed on a compressive strength tester, and the load was increased along the axis of the core column at a rate of 0.5 MPa per second until the pressure at which the core column failed was the compressive strength P1. The compressive strength of the original unimmersed core was recorded as P0, which was 6.9 MPa. Compressive index = P1 / P0.

[0118] The core column was prepared by the following method: 100 g of API-compliant drilling-grade bentonite was selected, placed in a drying oven, and dried at 105°C for 4 h. After being taken out and cooled to room temperature, 25 g of the dried bentonite was weighed, 3 mL of distilled water was added, the bentonite and distilled water were mixed evenly, and pressed at a pressure of 10 MPa for 5 min to make a core column with a diameter of 2.4 cm and a height of 2.6 cm.

[0119] 3) Lubricity

[0120] The test method is as follows: immerse the slider in the extreme pressure lubrication instrument into a 2.0% sample of the base fluid used to prepare the drilling fluid to be tested, adjust the torque wrench value to 16.95N / m, operate the instrument for 5 minutes, and read the value displayed on the instrument when the slider is immersed in the 2.0% sample of the base fluid used to prepare the drilling fluid as X; immerse the slider in the instrument in clean water, adjust the torque wrench value to 16.95N / m, operate the instrument for 5 minutes, and read the value displayed on the instrument when the slider is immersed in clean water as Y. The extreme pressure lubrication coefficient calculation formula is:

[0121] In the above formula: K is the extreme pressure lubrication coefficient; X is the value displayed on the instrument when the slider is immersed in a 2.0% base fluid sample used to prepare drilling fluid; Y is the value displayed on the extreme pressure lubrication instrument when the slider is immersed in clean water, which is 41.

[0122] 4) Fluid loss reduction

[0123] According to GB / T 16783.1-2014, "Field Testing of Drilling Fluids in the Petroleum and Natural Gas Industry - Part 1: Water-Based Drilling Fluids," the fluid loss of a 4% sodium bentonite-based slurry was measured before and after adding 2% of the Example and Comparative Example samples. The fluid loss of the 4% sodium bentonite-based slurry before addition was 48 mL. The test conditions were high-temperature aging at 210°C for 16 hours.

[0124] The preparation method of 4% sodium bentonite-based slurry is as follows: 2.0 g of anhydrous sodium carbonate and 40 g of sodium bentonite for drilling fluid testing are added to 1 L of water, stirred for 20 minutes, and then cured at room temperature for 24 hours to prepare the slurry.

[0125] Scanning electron microscope photographs of the medium-pressure filter cake before and after adding 2% of the sample from Example 1 to the 4wt% sodium bentonite-based slurry are shown in Figures 6 and 7, respectively. As can be seen from Figures 6 and 7, the medium-pressure filter cake prepared by filter press with the 4wt% sodium bentonite-based slurry has a rough, uneven surface and relatively large porosity. In contrast, the medium-pressure filter cake prepared by filter press with the 4wt% sodium bentonite-based slurry added to 2% of the sample from Example 1 has a smooth surface, forming a dense adsorption film with no voids. This effectively prevents filtrate from invading the formation, ensuring the wellbore stabilization effect of the formation. Furthermore, the presence of the adsorption film effectively reduces the friction between the drill bit and the wellbore rock, demonstrating a good lubrication and anti-sticking effect.

[0126] 5) Biological toxicity

[0127] Biotoxicity EC 50 The test method of the value is as follows: add the samples of the embodiment and comparative example provided by the present invention into a sodium chloride solution with a mass concentration of 3%, and prepare 0 mg.dm -3 、5000mg.dm -3 、10000mg.dm -3 、25000mg.dm -3 、50000mg.dm -3 、100000mg.dm -3 10 mL of each test sample solution was added and allowed to stand for 60 min. 10 mg of luminescent bacteria T3 powder was added to the above test sample solution in sequence and thoroughly shaken and mixed. The biotoxicity EC of the luminescent bacteria after 15 min of contact with the test sample solution was measured using a 3% sodium chloride solution as a control. 50 Value. EC 50 When the value is ≥30000 mg / L, it is considered to have no biological toxicity and is the allowable discharge standard.

[0128] The above test results are shown in Tables 1 and 2, wherein Table 1 shows the performance of the raw materials of Example 4, namely, multi-branched polyetheramine, aminocyclodextrin, cationic chitosan, silanol alkyl glycoside and sulfonylglycerol glycoside, and Table 2 shows the performance of the samples of the examples and comparative examples. Table 2 was conducted according to the method for testing the performance of the raw materials in Example 4 in Table 1, and the test conditions were the same as the test conditions used for the performance test of the raw materials in Example 4 in Table 1.

[0129] Table 1 Properties of the raw materials used in Example 4: multi-branched polyetheramine, aminocyclodextrin, cationic chitosan, silanolamine alkyl glycoside and sulfonylamino glyceryl glycoside

[0130] Table 2 Performance of Examples and Comparative Examples

[0131] As can be seen from Table 2, the above-mentioned cationic chitosan, silanol alkyl glycoside and optional multi-branched polyetheramine, amino cyclodextrin, and sulfonylamino glyceryl glycoside are uniformly mixed, stirred at a certain temperature for a certain time under the protection of inert gas, and a synergistic effect is exerted. The base fluid for preparing the drilling fluid obtained, after high-temperature aging at 210°C for 16 hours, has a shale primary recovery rate of ≥96.95% for the 2% embodiment sample; the relative inhibition rate of the 2% embodiment sample on the calcium soil-based slurry is ≥97.97%, and the relative inhibition rate of the 2% comparative example sample on the calcium soil-based slurry is ≥88.95%. It is illustrated that the base fluid for preparing drilling fluid prepared in the embodiment of the present invention exhibits outstanding properties such as anti-collapse, wall solidification, lubrication and anti-sticking, plugging and reducing filtration, and has comparable properties to oil-based drilling fluid. In addition, the composite water-based drilling fluid is green and environmentally friendly, and can meet the performance requirements for preparing drilling fluid. Therefore, the drilling fluid composition provided by the present invention enables the prepared base fluid to have both the anti-collapse, lubrication and anti-sticking, plugging and reducing filtration properties of oil-based drilling fluid and the wall solidification and environmental protection properties of water-based drilling fluid. The base fluid is a drilling fluid composition with excellent performance.

Claims

1. A drilling fluid composition, comprising silanol amino alkyl glycoside and cationic chitosan, and the composition has an extreme pressure lubrication coefficient of 0.001-0.05 and a compression resistance index of 1.3-5.

2. The composition according to claim 1, wherein The extreme pressure lubrication coefficient of the composition is 0.005-0.025 and the compression resistance index is 1.5-3.

3. The composition according to claim 1 or 2, wherein The composition also contains a multi-branched polyetheramine and a sulfonamidoglyceryl glycoside.

4. The composition according to claim 3, wherein Based on the total amount of the composition, the content of the multi-branched polyetheramine is 1-15% by mass, preferably 3-12% by mass, the content of the silanylaminoalkyl glycoside is 40-90% by mass, preferably 40-58% by mass, the content of the sulfonylaminoglyceryl glycoside is 5-30% by mass, preferably 15-25% by mass, and the content of the cationic chitosan is 1-11% by mass, preferably 3-7% by mass.

5. The composition according to claim 3 or 4, wherein The silanol amino alkyl glycoside has a structure shown in the following formula I: In formula I, R1 is a C1-C14 alkyl group, m is 1-16, and relative to the total amount of silanol amino alkyl glycoside, the content of X is 25-60 mass %, preferably 35-55 mass %, the content of Y is 30-55 mass %, preferably 40-50 mass %, and the content of Z is 0.2-60 mass %, preferably 0.2-55 mass %; X, Y, and Z are each at least one of H, an unsaturated amide residue, an unsaturated siloxane residue, a polyether group, and a polyene polyamine residue, and X, Y, and Z are different; Preferably, X, Y, and Z are each at least one of H, a group represented by the following formula I-1), a group represented by the following formula I-2), and a group represented by the following formula I-3, and X, Y, and Z are different; Preferably, Y comprises an unsaturated amide residue and an unsaturated siloxane residue; In formula I-1), R2 is a C1-C3 alkyl group, n is 1-2, and o is 0-4; In formula I-2), R3 is H or C1-C4 alkyl, and p is 1-30; In formula I-3), R4 is a C1-C4 alkyl group, and q is 1-20; Preferably, Y contains a group represented by the above formula I-2) and a group represented by the above formula I-3); The cationic chitosan has a structure shown in the following formula II; In formula II, R is an alkyl group having 1 to 3 carbon atoms, m is 1200 to 3100, and n is 1 to 2.

6. The composition according to claim 3, 4 or 5, wherein The multi-branched polyetheramine has a structure shown in Formula III, In formula III, m is 1-16, n is 1-2, and o is 0-4.

7. The composition according to any one of claims 3 to 6, wherein The sulfonylaminoglyceryl glycoside has a structure shown in the following formula IV: In formula IV, m is 1-3, and the content of X is 30-70 mass %, preferably 35-55 mass %, and the content of Y is 20-50 mass %, preferably 25-40 mass % relative to the total amount of sulfonylaminoglyceryl glycoside; X and Y are each a group represented by the following formula IV-1) or a group represented by the following formula IV-2), and X and Y are different; In formula IV-1), R1 and R2 are each independently selected from an alkyl group having 1 to 3 carbon atoms, n is 1 to 10, o is 1 to 10, and p is 0 to 4.

8. The composition according to any one of claims 1 to 7, wherein The composition further contains aminocyclodextrin. Preferably, based on the total amount of the composition, the content of aminocyclodextrin is 2-45% by mass, and more preferably 10-40% by mass.

9. The composition according to claim 8, wherein The aminocyclodextrin has a structure shown in the following formula V In formula V, based on the total amount of aminocyclodextrin, the content of R is 30-70 mass %, preferably 40-55 mass %, and R has the structure shown in the following structural formula i In formula i, m is 1-2, and n is 0-4.

10. Use of the composition according to any one of claims 1 to 9 in drilling fluid.

11. A drilling fluid comprising the composition according to any one of claims 1 to 9.

12. The drilling fluid according to claim 11, wherein: Based on the total amount of the drilling fluid, the content of the composition is 20-60 mass %.

13. A method for preparing a drilling fluid base fluid, the method comprising: In parts by mass, 0-15 parts, preferably 3-12 parts of multi-branched polyetheramine, 0-45 parts, preferably 10-40 parts of aminocyclodextrin, 1-10 parts, preferably 3-7 parts of cationic chitosan, 40-60 parts, preferably 42-58 parts of silanylamino alkyl glycoside, and 0-30 parts, preferably 18-24 parts of sulfonylamino glyceryl glycoside are stirred and mixed uniformly at 60-85° C. under the protection of inert gas.

14. The preparation method according to claim 13, wherein: The inert gas is nitrogen and / or helium.

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