Use of organosilicon compounds as set retarding agents for oil well cements or in the preparation of oil well cements

Abstract

The present application provides an application of an organic silicon compound as a retarding agent for oil well cement or in the preparation of oil well cement, wherein the organic silicon compound comprises one or more of the structures shown in the following formulae I-1 to I-4. The organic silicon compound of the present application can be used as a retarding agent for the preparation of oil well cement, and the oil well cement prepared at high temperature not only has suitable initial and final setting times, but also has high compressive strength.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to the application of an organosilicon compound as a retarder for oil well cement or in the preparation of oil well cement. Background Technology

[0002] Alkali-activated cementitious materials are a new type of low-carbon cementitious material composed of two components: an alkali activator and a cementitious precursor. They have excellent mechanical properties and durability. However, the setting time of alkali-activated cementitious materials is too short to meet the needs of actual construction. Therefore, it is necessary to add a retarder to adjust the setting time of alkali-activated cementitious material products.

[0003] To reduce the carbon footprint of cementitious materials, using alkali-activated materials as oil well cement is of great significance for carbon reduction in oil well cement. Oil well cement is a type of special cement mainly used to bind the annular space between the wellbore and casing of oil and gas wells, thus requiring construction and service at high temperatures. Because oil well cement is often exposed to high temperatures during construction, the hydration process of the cementitious materials is greatly accelerated. Therefore, retarders are needed to slow down the hydration process and extend the thickening time of the cement. Alkali-activated materials have a short thickening time at room temperature, and when used as oil well cement, the thickening time is even shorter at high temperatures. Therefore, it is necessary to develop retarders suitable for alkali-activated material systems to meet construction requirements.

[0004] Retarder is an additive that reduces the hydration rate and heat of hydration of cement and other cementitious materials, thus prolonging the setting time. Although there are many types of retarders suitable for high temperatures, most research focuses on silicate cement-based oil well cements. In alkali-activated material systems, the main components acting as retarders include borax or other boron-containing inorganic substances, phosphates, sodium gluconate, zinc salts, barium salts, etc. There are no reports of using silane molecules as retarders for oil well cements. Summary of the Invention

[0005] In order to solve one of the aforementioned technical problems in the prior art, the present invention provides a new use for organosilicon compounds.

[0006] The technical solution of the present invention is as follows:

[0007] This invention provides the use of organosilicon compounds as retarder for oil well cement or in the preparation of oil well cement, wherein the organosilicon compounds include those with the general formula R. 2(4-n) Si(OR1) nThe organosilicon compound or a composition thereof; wherein n is 1, 2, 3 or 4; R1 is independently selected from C1-C4 alkyl, C1-C4 alkyl substituted with one or more C1-C4 alkoxy groups, R2 is independently selected from substituted or unsubstituted C1-C10 straight-chain or branched alkyl, substituted or unsubstituted C1-C10 straight-chain or branched alkyl containing one or more ether bonds, substituted or unsubstituted C2-C10 straight-chain or branched alkenyl, and when R2 contains a substituent, the substituent is one or more, and each is independently selected from C2-C10 alkenyl, C1-C10 alkoxy, C3-C10 cycloalkyl, C2-C10 oxygen-containing heterocyclic group, C6-C15 aryl, -NR a R b -N + (R c (R) d (R) e )X - , hydroxyl, mercapto, thiocyanate, -NCO, C2-C10 ester, carboxyl, acid anhydride, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C10 straight-chain or branched alkyl groups; R c R d and R e Each is independently selected from C1-C10 straight-chain or branched alkyl groups, X - It represents anion.

[0008] In this invention, the operating temperature of the oil well cement can be 50-250℃, for example, 50℃, 60℃, 65℃, 70℃, 80℃, 85℃, 90℃, 100℃, 120℃, 150℃, 180℃, 200℃, 220℃, 250℃, or any value between them. In some embodiments, the operating temperature of the oil well cement is 60-250℃. In some embodiments, the operating temperature of the oil well cement is 60-200℃. In some embodiments, the operating temperature of the oil well cement is 85-200℃.

[0009] In this invention, the oil well cement can be used for cementing engineering of oil wells and gas wells.

[0010] In this invention, "the operating temperature of oil well cement" refers to the ambient temperature during the service life of oil well cement.

[0011] According to some embodiments of the present invention, R1 is independently selected from C1-C4 alkyl groups.

[0012] According to some embodiments of the present invention, R1 is independently selected from C1-C4 alkyl groups substituted with one or more methoxy, ethoxy, or propoxy substituents.

[0013] According to some embodiments of the present invention, the organosilicon compound comprises one or more of the structures shown in formulas I-1 to I-4:

[0014]

[0015] Among them, R 1a R 1b R 1c and R 1d The definition is the same as the definition of R1 mentioned above in this invention; R 2a R 2b and R 2c The definition is the same as the definition of R2 mentioned above in this invention.

[0016] In some implementations, R 1a R 1b R 1c and R 1d Independently selected from methyl, ethyl, propyl, or isopropyl;

[0017] In some implementations, R 2a R 2b and R 2c Independently selected from substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups, substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups containing one or more ether bonds, substituted or unsubstituted C2-C10 straight-chain or branched alkenyl groups, and when R 2a R 2b and R 2c When substituents are present, the substituents are one or more, and each is independently selected from C3-C10 cycloalkyl, C2-C10 oxygen-containing heterocyclic groups, and -NR. a R b -N + (R c (R) d (R) e )X - , hydroxyl, mercapto, thiocyanate, -NCO, C2-C10 ester, C6-C10 aryl, carboxyl, acid anhydride, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C6 straight-chain or branched alkyl groups; R c R d and R eAlkyl groups independently selected from C1-C6 straight-chain or branched alkyl groups; X - The anions are selected from the following acid radicals produced when the acids ionize: hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, maleic acid, succinic acid, citric acid, fumaric acid, salicylic acid, L-tartaric acid, fumaric acid, acetic acid, nitric acid, phosphoric acid, oxalic acid, lactic acid, lysine, and aspartic acid.

[0018] In some implementations, R c R d and R e Alkyl groups independently selected from C1-C4 straight-chain or branched alkyl groups, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc. As a non-limiting example, -N + (R c (R) d (R) e )X - It can represent trimethylammonium chloride group, trimethylammonium bromide group, triethylammonium chloride group, triethylammonium bromide group, etc.

[0019] According to some embodiments of the present invention, in formulas I-1 to I-4, R 2a R 2b and R 2c Independently selected from substituted or unsubstituted C1-C8 straight-chain or branched alkyl groups, substituted or unsubstituted C1-C8 straight-chain or branched alkyl groups containing 1-2 ether bonds, and substituted or unsubstituted C2-C6 straight-chain or branched alkenyl groups, and when R 2a R 2b and R 2c When substituents are present, the substituents are one or more and each is independently selected from C3-C6 cycloalkyl, C2-C6 oxygen-containing heterocyclic groups, and -NR. a R b , mercaptophenyl, C2-C6 ester groups, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C4 straight-chain or branched alkyl groups.

[0020] According to some embodiments of the present invention, in formulas I-1 to I-4, R2 is independently selected from substituted or unsubstituted C1-C6 straight-chain or branched alkyl groups.

[0021] According to some embodiments of the present invention, in formulas I-1 to I-4, R 2a R 2b and R 2cThe substituent is independently selected from the following groups, whether substituted or unsubstituted: methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, vinyl, propenyl, isopropenyl, butenyl; and when R2 contains a substituent, the substituent is one or more, and each is independently selected from vinyl, propenyl, methoxy, ethoxy, propoxy, isopropoxy, butoxy, ... Amino, mercapto, phenyl, CH2=C(CH3)COO-, carboxyl, acid anhydride, and combinations thereof.

[0022] According to some embodiments of the present invention, in formulas I-1 to I-4, R 2a R 2b and R 2c It is independently selected from substituted or unsubstituted methyl, substituted or unsubstituted ethyl, or substituted or unsubstituted vinyl.

[0023] According to some embodiments of the present invention, in formulas I-1 to I-4, when R 2a R 2b and R 2c When substituents are present, the substituents are one or more, and each is independently selected from C2-C6 alkenyl, C1-C6 alkoxy, C2-C6 oxygen-containing heterocyclic, -NR a R b , thiol group, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C4 straight-chain or branched alkyl groups. In some embodiments, R a and R b Each is independently selected from hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl.

[0024] According to some embodiments of the present invention, in formulas I-1 to I-4, when R 2a R 2b and R 2c When a substituent is present, the substituent is one or more, and each is independently selected from C2-C4 alkenyl, C1-C4 alkoxy, C2-C6 oxygen-containing heterocyclic, amino, mercapto, phenyl, CH2=C(CH3)COO-, carboxyl, acid anhydride, and combinations thereof.

[0025] According to some embodiments of the present invention, in formulas I-1 to I-4, when R 2a R 2b and R 2c When substituents are present, the substituents are one or more, and each is independently selected from vinyl, propenyl, methoxy, ethoxy, propoxy, butoxy, etc. Amino, mercapto, phenyl, CH2=C(CH3)COO-, and combinations thereof.

[0026] In some embodiments, R1 in formulas I-1 to I-4 is methyl. In some embodiments, R1 in formulas I-1 to I-4 is ethyl.

[0027] In some embodiments, in formulas I-1 to I-4, R 2a R 2b and R 2c It is methyl. In some embodiments, in formulas I-1 to I-4, R 2a R 2b and R 2c It is ethyl. In some embodiments, in formulas I-1 to I-4, R 2a R 2b and R 2c It is vinyl. In some embodiments, in formulas I-1 to I-4, R 2a R 2b and R 2c for

[0028] In some embodiments, in formulas I-1 to I-4, R 1a R 1b R 1c and R 1d All are methyl, R 2a R 2b and R 2c All are ethyl. In some embodiments, in formulas I-1 to I-4, R 1a R 1b R 1c and R 1d All are ethyl, R 2a R 2b and R 2c All are methyl groups.

[0029] In some embodiments, in formulas I-1 to I-4, R 1a R 1b R 1c R 1d R 2a R 2b and R 2c All are methyl. In some embodiments, in formulas I-1 to I-4, R 1a R 1b R 1c R 1d R 2a R 2b and R 2c All are ethyl.

[0030] According to some embodiments of the present invention, the organosilicon compound includes methoxytrimethylsilane, dimethoxydimethylsilane, trimethoxymethylsilane, tetramethoxysilane, ethoxytrimethylsilane, diethoxydimethylsilane, triethoxymethylsilane, tetraethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyldimethoxysilane, aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethyldimethoxysilane, diethylaminopropylmethyldiethoxysilane, diethylaminopropylmethyldiethoxysilane, diethylaminopropyltrimeth ... The following are one or more of the following: 3-glycidyl etheroxypropyltrimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-glycidyl etheroxypropylmethyldiethoxysilane, 3-glycidyl etheroxypropylmethyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, vinyltriisopropoxysilane, vinyldimethylethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, mercaptopropylmethyldimethoxysilane, octyltriethoxysilane, phenyltriethoxysilane, and methacryloxypropyltriethoxysilane.

[0031] According to some embodiments of the present invention, the organosilicon compound includes one or more of trimethylmethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, tetramethoxysilane, 3-glycidyl etheroxypropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, octyltriethoxysilane, methylvinyldiethoxysilane, phenyltriethoxysilane, and methacryloxypropyltriethoxysilane.

[0032] According to some embodiments of the present invention, the raw materials for preparing the oil well cement include cementitious materials, alkali activators, and retarders, wherein the retarder includes the organosilicon compound.

[0033] In some embodiments, the amount of the silicone compound is 1%-10% of the weight of the cementitious material, for example 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10% or any value between them, preferably 3%-8%. In some embodiments, the amount of the silicone compound is 5% of the weight of the cementitious material.

[0034] According to some embodiments of the present invention, the amount of the alkali activator is 3%-80% of the weight of the cementitious material, for example, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 40%, 50%, 60%, 70%, 80%, or any value between therewith. In some embodiments, the amount of the alkali activator is 8%-50% of the weight of the cementitious material. In some embodiments, the amount of the alkali activator is 10%-30% of the weight of the cementitious material. In some embodiments, the amount of the alkali activator is 20%-30% of the weight of the cementitious material. In some embodiments, the amount of the alkali activator is 25%-30% of the weight of the cementitious material.

[0035] In this invention, the cementing material includes, but is not limited to, one or more of the following: metallurgical slag, mineral powder, fly ash, steel slag, volcanic ash, metakaolin, and cement. In some embodiments, the cementing material includes mineral powder. In some embodiments, the cementing material includes mineral powder and a combination of one or two selected from metakaolin and fly ash.

[0036] In this invention, the alkaline activator includes, but is not limited to, one or more of the following: alkali metal oxides, alkaline earth metal oxides, alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal salts, and alkaline earth metal salts. In some embodiments, the alkaline activator includes one or more of the following: alkali metal carbonates, alkali metal sulfates, alkali metal silicates, alkali metal aluminates, alkali metal formates, alkali metal acetates, alkali metal hydroxides, alkaline earth metal carbonates, alkaline earth metal sulfates, alkaline earth metal silicates, alkaline earth metal aluminates, alkaline earth metal formates, alkaline earth metal acetates, and alkaline earth metal hydroxides. In some embodiments, the alkaline activator includes one or more of the following: sodium hydroxide, water glass, sodium sulfate, and calcium hydroxide.

[0037] According to some embodiments of the present invention, the method for preparing the oil well cement includes the following steps:

[0038] The cementitious material, alkali activator, and retarder are mixed with water to obtain cement slurry.

[0039] In this invention, the alkali activator can be mixed with water first, and then mixed with the cementitious material; alternatively, the alkali activator can be directly mixed with the cementitious material; or the retarder can be mixed with the alkali activator first, and then mixed with the cementitious material. This invention does not impose any special limitations on the method of adding the raw materials.

[0040] According to some embodiments of the present invention, in the method for preparing the oil well cement, the mass ratio (water-to-solid ratio) of water to the cementitious material is 0.3-1.2, for example, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.2 or any value between them, preferably 0.4-1.0.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] This invention uses organosilicon compounds with one or more siloxy groups (-Si-O-) as retarder for oil well cement, which can prolong the setting time of oil well cement at higher service temperatures (50-250℃), avoid the excessively rapid setting of oil well cement at high temperatures, and does not significantly affect its compressive strength, thus providing more options for the use of oil well cement retarder. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention in any way. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of this disclosure. Such structures and techniques have also been described in many publications.

[0044] definition

[0045] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly used in the field to which this invention pertains. For the purposes of interpreting this specification, the following definitions will apply, and where appropriate, terms used in the singular will also include the plural forms, and vice versa.

[0046] In this invention, the term "cementing material," also known as a binder, refers to a substance that, under physical and chemical action, can transform from a slurry into a solid, stone-like substance and can bind other materials to form a composite solid with a certain mechanical strength. In this paper, aluminosilicates (such as cement, metakaolin, and volcanic ash) and industrial waste (such as slag, fly ash, silica fume, and steel slag) both fall under the category of cementing materials.

[0047] In this invention, the term "alkali-activated cementitious material," also known as "chemically activated cementitious material," refers to a hydraulic cementitious material prepared using the catalytic principle of an alkali activator (such as caustic alkali, alkali-containing silicates, aluminates, etc.). It is mainly composed of calcined natural minerals or industrial waste residues (such as slag, fly ash, silica fume, steel slag, etc.) containing aluminosilicates with a certain rapid cooling and heating history, and an alkali activator. It has the characteristics of rapid setting and hardening, high strength, and high temperature resistance, and is used in civil engineering, solid waste, high-strength, sealing, and high-temperature environment projects.

[0048] In this invention, the term "alkyl" refers to a straight-chain or branched hydrocarbon group having a specified number of carbon atoms (i.e., C1-C6 means containing 1, 2, 3, 4, 5, or 6 carbon atoms). Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, sec-butyl, n-pentyl, n-hexyl, and similar alkyl groups.

[0049] In this invention, the term "alkoxy" refers to a straight-chain, branched, or cyclic alkyl group linked by an ether oxygen atom, the free valence of which originates from the ether oxygen atom. Representative examples of alkoxy groups include (but are not limited to): methoxy, ethoxy, propoxy, isopropoxy, and butoxy.

[0050] In this invention, the term "alkenyl" refers to a straight-chain or branched hydrocarbon group containing one or more double bonds and having a specified number of carbon atoms. For example, "C2-C6 alkenyl" refers to a group containing 2 to 6 carbon atoms. Alkenyl groups include, but are not limited to: vinyl, propenyl, butenyl, 1-methyl-2-buten-1-yl, heptenyl, octenyl, etc.

[0051] In this invention, the term "alkoxy" refers to an alkyl group that is attached to the remainder of the molecule via an oxygen atom, wherein the alkyl group has the meaning as described herein. Examples of alkoxy groups include, but are not limited to, methoxy (MeO, -OCH3), ethoxy (EtO, -OCH2CH3), 1-propoxy (n-PrO, n-propoxy, -OCH2CH2CH3), 2-propoxy (i-PrO, i-propoxy, -OCH(CH3)2), 1-butoxy (n-BuO, n-butoxy, -OCH2CH2CH2CH3), 2-methyl-1-propoxy (i-BuO, i-butoxy, -OCH2CH(CH3)2), 2-butoxy (s-BuO, s-butoxy, -OCH(CH3)CH2CH3), and so on.

[0052] In this invention, the term "cycloalkyl" refers to a monovalent or polyvalent, non-aromatic, saturated or partially unsaturated ring that does not contain heteroatoms, including monocyclic or bicyclic rings. The bicyclic carbocyclic ring can be a bicyclic [4,5], [5,5], [5,6], or [6,6] system, and the bicyclic carbocyclic ring can also be a bicyclic [5,6] or [6,6] system. Includes, but is not limited to, cycloalkyl, cycloalkenyl, and cycloynyl groups. Examples of cyclic aliphatic groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, 1-cyclopentyl-1-enyl, 1-cyclopentyl-2-enyl, 1-cyclopentyl-3-enyl, cyclohexyl, 1-cyclohexyl-1-enyl, 1-cyclohexyl-2-enyl, 1-cyclohexyl-3-enyl, cyclohexadienyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, etc.

[0053] In this invention, the term "heterocyclic group" refers to a monocyclic, bicyclic, or tricyclic system in which one or more carbon atoms in the ring are independently and optionally substituted by heteroatoms. The ring may be fully saturated or contain one or more degrees of unsaturation, but is by no means aromatic. When at least one carbon atom in the ring is substituted by an oxygen atom, the "heterocyclic group" is an "oxygen-containing heterocyclic group," which includes, but is not limited to, those mentioned above.

[0054] In this invention, "aryl" refers to a carbocyclic system containing 6-15 membered rings, including monocyclic, bicyclic, and tricyclic systems, wherein at least one ring system is aromatic, and each ring system contains 3-7 membered rings with only one attachment point connected to the rest of the molecule. Examples include phenyl, naphthyl, and anthracene, etc.

[0055] In this invention, "ester group" refers to -COOR, and R represents alkyl. The definition of alkyl is as described above, and R is preferably a C2-C6 alkyl group.

[0056] The following embodiments are provided to aid in understanding the present invention. However, it should be understood that these embodiments are for illustrative purposes only and do not constitute any limitation. The actual scope of protection of the present invention is set forth in the claims. It should be understood that any modifications and changes can be made without departing from the spirit of the present invention.

[0057] Unless otherwise specified, all reagents used in the following experiments of this invention are commercially available products or reagents prepared according to conventional methods. Unless otherwise specified, all methods used in the experiments are conventional experimental methods. Unless otherwise specified, all instruments used in the experiments are commercially available.

[0058] The structural information of the retarders used in this paper is shown in Table 1 below.

[0059] Table 1

[0060]

[0061] Examples 1-16

[0062] Preparation of alkali-activated cementitious oil well cement:

[0063] Weigh the samples according to the composition (precursor, activator, retarder) of each embodiment in Table 2 below. Mix the activator, water and retarder to obtain the activator solution. Mix the precursor and activator solution and stir thoroughly to obtain the sample to be tested.

[0064] Compare with Examples 1-8

[0065] In each comparative example, the preparation of alkali-activated cementitious oil well cement was carried out in accordance with the methods described in Examples 1 to 16 above, and the raw materials used are shown in Table 2.

[0066] Table 2

[0067]

[0068]

[0069]

[0070] Note: The dosage of alkali activator and retarder in Table 2 refers to the dosage in the precursor.

[0071] The thickening time of the test samples obtained from the above embodiments and control examples was tested. The thickening time test method was carried out in accordance with the thickening time test method specified in "Test Methods for Oil Well Cement GB / T 19139-2012", and the results are shown in Table 3.

[0072] Table 3

[0073]

[0074]

[0075] As can be seen from Table 3 above, the comparison between Comparative Example 1 and Examples 1-4 shows the effect of different silanes (different siloxy groups) on thickening time. All four silanes in Examples 1-4 exhibited good retarding effects, and the thickening times of Examples 1-4 were much longer than those of Comparative Example 1. The retarding effects of trimethylmethoxysilane used in Example 1 and methyltrimethoxysilane used in Example 3 were superior to those of dimethyldimethoxysilane used in Example 2 and tetramethoxysilane used in Example 4.

[0076] A comparison of Comparative Example 1 and Examples 5-8, 17, and 18 shows the effect of different substituents on the thickening time of the silane in the retarder. Compared to Comparative Example 1, Examples 5-8, using silanes with different substituents, all exhibited better retarding effects, with significantly prolonged thickening times. Among them, Example 5, with the addition of 3-glycidyl etheroxypropylmethyldiethoxysilane, and Example 6, with the addition of 3-aminopropyltrimethoxysilane, showed even more significant retarding effects, with thickening times exceeding 10 hours.

[0077] Comparisons between Comparative Example 1 and Example 5, Comparative Example 2 and Example 9, Comparative Example 3 and Example 10, Comparative Example 4 and Example 11, and Comparative Example 5 and Example 12 show the influence of different precursor types, activator types, and activator specifications on thickening time. Silanes exhibited good retarding effects and prolonged thickening time in different alkaline activation systems.

[0078] A comparison with Example 1 and Examples 5, 13-14, and 16 shows the effect of retarder dosage on thickening time. As the retarder dosage increases, the thickening time gradually lengthens.

[0079] As can be seen from Table 3 above, silane exhibits good retarding effect in the range of 85-200℃, making it suitable for high-temperature oil well cement.

[0080] The technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made in accordance with the technical solutions of the present invention fall within the protection scope of the present invention.

Claims

1. The application of organosilicon compounds as retarder for oil well cement or in the preparation of oil well cement, among which, The organosilicon compound includes one or more of the structures shown in formulas I-1 to I-4 below; Among them, R 1a R 1b R 1c and R 1d Independently selected from C1-C4 alkyl groups, C1-C4 alkyl groups substituted with one or more C1-C4 alkoxy groups, R 2a R 2b and R 2c Independently selected from substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups, substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups containing one or more ether bonds, substituted or unsubstituted C2-C10 straight-chain or branched alkenyl groups, and when R 2a R 2b and R 2c When substituents are present, the substituents are one or more, and each is independently selected from C2-C10 alkenyl, C1-C10 alkoxy, C3-C10 cycloalkyl, C2-C10 oxygen-containing heterocyclic, C6-C15 aryl, -NR a R b -N + (R c (R) d (R) e )X - , hydroxyl, mercapto, thiocyanate, -NCO, C2-C10 ester, carboxyl, acid anhydride, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C10 straight-chain or branched alkyl groups; R c R d and R e Each is independently selected from C1-C10 straight-chain or branched alkyl groups, X - Indicates anion; Preferably, the operating temperature of the oil well cement is 50-250℃.

2. The application according to claim 1, characterized in that, R 1a R 1b R 1c and R 1d Independently selected from methyl, ethyl, propyl, or isopropyl; R 2a R 2b and R 2c Independently selected from substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups, substituted or unsubstituted C1-C10 straight-chain or branched alkyl groups containing one or more ether bonds, substituted or unsubstituted C2-C10 straight-chain or branched alkenyl groups, and when R 2a R 2b and R 2c When substituents are present, the substituents are one or more, and each is independently selected from C3-C10 cycloalkyl, C2-C10 oxygen-containing heterocyclic groups, and -NR. a R b -N + (R c (R) d (R) e )X - , hydroxyl, mercapto, thiocyanate, -NCO, C2-C10 ester, C6-C10 aryl, carboxyl, acid anhydride, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C6 straight-chain or branched alkyl groups, R c R d and R e Alkyl groups independently selected from C1-C6 straight-chain or branched alkyl groups; X - The anions are selected from the following acid radicals produced when the acids ionize: hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, maleic acid, succinic acid, citric acid, fumaric acid, salicylic acid, L-tartaric acid, fumaric acid, acetic acid, nitric acid, phosphoric acid, oxalic acid, lactic acid, lysine, and aspartic acid.

3. The application according to claim 1 or 2, characterized in that, R 2a R 2b and R 2c Independently selected from substituted or unsubstituted C1-C8 straight-chain or branched alkyl groups, substituted or unsubstituted C1-C8 straight-chain or branched alkyl groups containing 1-2 ether bonds, and substituted or unsubstituted C2-C6 straight-chain or branched alkenyl groups, and when R 2a R 2b and R 2c When substituents are present, the substituents are one or more and each is independently selected from C3-C6 cycloalkyl, C2-C6 oxygen-containing heterocyclic groups, and -NR. a R b , mercapto, phenyl, C2-C6 ester groups, and combinations thereof, R a and R b Each is independently selected from hydrogen, C1-C4 straight-chain or branched alkyl groups; Preferably, R 2a R 2b and R 2c The following groups are independently selected, either substituted or unsubstituted: methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, vinyl, propenyl, isopropenyl, butenyl; and when R 2a R 2b and R 2c When substituents are present, the substituents are one or more, and each is independently selected from vinyl, propenyl, methoxy, ethoxy, propoxy, isopropoxy, butoxy, etc. Amino, mercapto, phenyl, CH2=C(CH3)COO-, carboxyl, acid anhydride, and combinations thereof.

4. The application according to any one of claims 1-3, characterized in that, The organosilicon compounds include methoxytrimethylsilane, dimethoxydimethylsilane, trimethoxymethylsilane, tetramethoxysilane, ethoxytrimethylsilane, diethoxydimethylsilane, triethoxymethylsilane, tetraethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyldimethoxysilane, aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethyldimethoxysilane, and diethylaminomethyltriethoxysilane. The following are one or more of the following: silane, diethylaminopropyltrimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-glycidyl etheroxypropyltriethoxysilane, 3-glycidyl etheroxypropylmethyldiethoxysilane, 3-glycidyl etheroxypropylmethyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, vinyltriisopropoxysilane, vinyldimethylethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, mercaptopropylmethyldimethoxysilane, octyltriethoxysilane, phenyltriethoxysilane, and methacryloxypropyltriethoxysilane; Preferably, the organosilicon compound includes one or more of trimethylmethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, tetramethoxysilane, 3-glycidyl etheroxypropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, octyltriethoxysilane, methylvinyldiethoxysilane, phenyltriethoxysilane, and methacryloxypropyltriethoxysilane.

5. The application according to any one of claims 1-4, characterized in that, The operating temperature of the oil well cement is 60-250℃, preferably 60-200℃.

6. The application according to any one of claims 1-5, characterized in that, The raw materials for preparing the oil well cement include cementitious materials, alkali activators, and retarder, wherein the retarder includes the organosilicon compound; Preferably, the amount of the organosilicon compound is 1%-10% of the weight of the cementitious material, more preferably 3%-8%.

7. The application according to claim 6, characterized in that, The cementing material includes one or more of the following: metallurgical slag, mineral powder, fly ash, steel slag, volcanic ash, metakaolin, and cement. Preferably, the cementing material comprises mineral powder, or comprises mineral powder and one or two selected from fly ash and metakaolin.

8. The application according to claim 6 or 7, characterized in that, The alkaline activator includes one or more of oxides, hydroxides and salts of alkali metals or alkaline earth metals. Preferably, the alkaline activator comprises one or more of the following: carbonates, sulfates, silicates, aluminates, formates, acetates, and hydroxides of alkali metals or alkaline earth metals. More preferably, the alkaline activator includes one or more of sodium hydroxide, water glass, sodium sulfate, and calcium hydroxide.

9. The application according to any one of claims 6-8, characterized in that, The amount of the alkali activator is 3%-80% of the weight of the cementitious material, preferably 8%-50%, and more preferably 10%-30%.

10. The application according to any one of claims 6-9, characterized in that, The method for preparing the oil well cement includes the following steps: The cementitious material, alkali activator, and retarder are mixed with water to obtain cement slurry; Preferably, the retarder is first mixed with the alkali activator, and then mixed with the cementitious material and water; Preferably, the mass ratio of water to the cementitious material is 0.3-1.2, more preferably 0.4-1.0.

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