A cementitious material admixture composition, cement slurry and its application

Abstract

This invention provides a cementitious material admixture composition, a cement slurry, and their applications. The admixture composition of this invention includes a retarder, a water loss reducer, and a latex. The retarder comprises a first retarder and a second retarder. The first retarder comprises a hydroxycarboxylic acid and / or a hydroxycarboxylate salt, and the second retarder comprises an unsaturated sulfonic acid monomer, a copolymer of an unsaturated carboxylic acid monomer and a cationic monomer. The admixture composition of this invention can ensure that the thickening time and water loss of aluminate cement slurry meet operational requirements while preventing cracking under hydrothermal conditions. It can be used for oil well cementing and carbon sequestration cementing.

Description

Technical Field

[0001] This invention belongs to the field of cementitious materials, specifically relating to a cementitious material admixture composition, cement slurry, and their applications. Background Technology

[0002] CO2 capture and storage (CCS) is gaining increasing attention as an emerging technology with the potential to achieve zero emissions from fossil fuels. This technology involves: collecting or capturing CO2 emitted by large industrial plants using fossil fuels (coal, oil, and natural gas); transporting the captured CO2 to suitable storage sites; and finally, injecting the CO2 in a supercritical state into deep underground formations for storage. However, cracking of the carbon sequestration cement stone and CO2 corrosion are significant factors threatening the safety of CCS and leading to storage failure.

[0003] Currently, the most commonly used cement system for oil well cementing and carbon sequestration cementing is the silicate cement system, whose hydration products mainly include hydrated calcium silicate, calcium hydroxide, and ettringite. Under certain humidity, temperature, and pressure conditions, CO2 can corrode the hydration products in the cement sheath of oil and gas wells, reducing the strength of the cement stone and increasing its permeability. This damages the cement sheath structure and creates oil and gas channeling pathways, leading to wellbore seal failure and seriously threatening the lifespan and safety of oil and gas wells. In addition, Sugama et al. invented a cement system in 1991 with calcium aluminate cement and phosphate or polyphosphate as the main solid components. This cement system has good CO2 corrosion resistance. However, numerous experiments have shown that the above-mentioned cement system has poor workability at 40–150℃, and there are problems such as difficulty in controlling the slurry thickening time and water loss performance. In addition, in oil well cementing engineering, in order to toughen, crack-resistant, and impermeable cement stone and enhance the stable and continuous bonding between the cement sheath and the steel pipe interface, latex is usually added. However, adding ordinary latex will cause the cement stone to crack under hydrothermal conditions. Summary of the Invention

[0004] To address one of the aforementioned technical problems in the prior art, the present invention provides a cementitious material admixture composition. Applying the admixture composition of the present invention to cementitious materials, especially aluminate cement, can effectively adjust the thickening time of the cement slurry, ensuring that the water loss of the cement slurry meets the working requirements while preventing the cement slurry from cracking under hydrothermal conditions, thereby improving cementing performance.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect, the present invention provides a gelling material admixture composition comprising a retarder, a water loss reducing agent, and a latex, wherein the retarder comprises a first retarder and a second retarder, the first retarder comprising a hydroxycarboxylic acid and / or a hydroxycarboxylate salt, and the second retarder comprising a copolymer of an unsaturated sulfonic acid monomer and an unsaturated carboxylic acid monomer and a cationic monomer.

[0007] In some embodiments, the first retarder comprises C2-C10 hydroxy fatty acids and / or C2-C10 hydroxy fatty acid salts. In some embodiments, the first retarder comprises C3-C8 hydroxy fatty acids and / or C3-C8 hydroxy fatty acid salts. The C3-C8 hydroxy fatty acids described in this invention include, but are not limited to, at least one of gluconic acid, tartaric acid, citric acid, and malic acid. The C3-C8 hydroxy fatty acid salts described in this invention include, but are not limited to, sodium salts, potassium salts, and calcium salts of C3-C8 hydroxy fatty acids.

[0008] In some embodiments, the unsaturated sulfonic acid monomer in the second retarder includes at least one of acrylamide sulfonic acid, ethylene sulfonic acid, styrene sulfonic acid, propylene sulfonic acid, methpropylene sulfonic acid, or a salt thereof.

[0009] In some preferred embodiments, the unsaturated sulfonic acid monomer in the second retarder includes at least one of 2-acrylamido-2-methylpropanesulfonic acid, sodium styrene sulfonate, sodium propylene sulfonate, sodium methpropylene sulfonate, sodium 3-allyloxy-2-hydroxy-1-propanesulfonate, and sodium vinylbenzene sulfonate.

[0010] In some embodiments, the unsaturated carboxylic acid monomer in the second retarder comprises a C2-C10 mono- or di-unsaturated carboxylic acid. In some preferred embodiments, the unsaturated carboxylic acid monomer in the second retarder comprises a C3-C8 mono- or di-unsaturated carboxylic acid. In some preferred embodiments, the unsaturated carboxylic acid monomer in the second retarder comprises a C3-C6 mono- or di-unsaturated carboxylic acid. In some more preferred embodiments, the unsaturated carboxylic acid monomer in the second retarder comprises at least one selected from acrylic acid, maleic acid, and itaconic acid.

[0011] In some embodiments, the cationic monomer in the second retarder includes a quaternary ammonium salt cationic monomer. The quaternary ammonium salt cationic monomers of this invention include, but are not limited to, at least one of: methacryloylpropyltrimethylammonium chloride, methacryloyloxyethyltrimethylammonium chloride, and dimethyldiallylammonium chloride.

[0012] In some embodiments, the copolymer of unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer in the second retarder is obtained by solution polymerization. In some specific embodiments, the preparation of the copolymer of unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer includes the following steps:

[0013] The unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer are polymerized in a solvent in the presence of a reducing agent, an initiator, and a chain transfer agent. Preferably, the solvent is water. Preferably, the polymerization temperature is 40–80°C. Preferably, the molar ratio of the unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer is 1:(1–10):(0.2–1.5). Preferably, the molar ratio of the initiator to the total molar ratio of the unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer is (0.005–0.1):1. Preferably, the molar ratio of the chain transfer agent to the total molar ratio of the unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer is (0.01–0.2):1. Preferably, the molar ratio of the initiator to the reducing agent is (1–5):1. Preferably, the initiator includes at least one of hydrogen peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, and benzoyl peroxide. Preferably, the reducing agent includes at least one of vitamin C, sodium sulfite, sodium bisulfite, potassium sulfite, potassium bisulfite, ferrous sulfate, and sodium formaldehyde sulfoxylate. Preferably, the chain transfer agent includes at least one of mercaptoacetic acid, mercaptopropionic acid, mercaptoethanol, mercaptopropanol, and sodium methylpropenesulfonate.

[0014] In some specific embodiments, the preparation of the copolymer of the unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer includes the following steps:

[0015] The unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer are mixed with water to obtain solution A;

[0016] The reducing agent and chain transfer agent are mixed with water to obtain solution B;

[0017] Solution A and solution B are mixed with an initiator and heated to 40–80°C for 2–8 hours to obtain a copolymer of the unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer.

[0018] In some preferred embodiments, the first retarder comprises citric acid and / or malic acid.

[0019] In some preferred embodiments, the second retarder comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, acrylic acid, and methacryloylpropyltrimethylammonium chloride.

[0020] In some preferred embodiments, the second retarder comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, maleic acid, and methacryloylpropyltrimethylammonium chloride.

[0021] In some preferred embodiments, the second retarder comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, itaconic acid, methacryloylpropyltrimethylammonium chloride, and dimethyl diallyl ammonium chloride.

[0022] In some preferred embodiments, the second retarder comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, sodium p-styrenesulfonate, acrylic acid, and methacryloylpropyltrimethylammonium chloride.

[0023] In some embodiments, the water loss reducing agent comprises a copolymer of an amide monomer with an unsaturated sulfonic acid monomer, a cationic monomer, and a silane monomer.

[0024] In some embodiments, the amide monomers include acrylamide monomers, preferably acrylamide and / or N,N-dimethylacrylamide.

[0025] In some embodiments, the unsaturated sulfonic acid monomer in the water loss reducing agent includes at least one of acrylamide sulfonic acid, ethylene sulfonic acid, styrene sulfonic acid, propylene sulfonic acid, methpropylene sulfonic acid, or a salt thereof. In some preferred embodiments, the unsaturated sulfonic acid monomer includes at least one of 2-acrylamido-2-methylpropanesulfonic acid, sodium styrene sulfonate, sodium propylene sulfonate, sodium methpropylene sulfonate, sodium 3-allyloxy-2-hydroxy-1-propanesulfonate, and sodium vinylbenzene sulfonate.

[0026] In some embodiments, the cationic monomer in the water loss reducing agent includes a quaternary ammonium salt cationic monomer. In some embodiments, the cationic monomer includes at least one selected from methacryloylpropyltrimethylammonium chloride, methacryloyloxyethyltrimethylammonium chloride, and dimethyldiallylammonium chloride.

[0027] In some embodiments, the silane monomer in the water loss reducing agent includes at least one of vinyltriethoxysilane (A151), vinyltrimethoxysilane (A171), vinyltri(β-methoxyethoxy)silane (A172), and γ-methacryloyloxypropyltrimethoxysilane (KH570).

[0028] In some embodiments, the copolymer of the amide monomer with the unsaturated sulfonic acid monomer, the cationic monomer, and the silane monomer is obtained by solution polymerization. In some specific embodiments, the copolymer of the amide monomer with the unsaturated sulfonic acid monomer, the cationic monomer, and the silane monomer includes the following steps:

[0029] The amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers are polymerized in a solvent in the presence of an initiator. Preferably, the solvent is water. Preferably, the polymerization temperature is 50–65°C. Preferably, the molar ratio of the amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers is 1:(0.1–0.5):(0.2–0.8):(0.01–0.02). Preferably, the initiator accounts for 0.1%–0.4% of the total mass of the amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers. Preferably, the initiator includes one or more of persulfates, peroxides, and redox initiators, preferably ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide-ascorbic acid, hydrogen peroxide-ferrous oxide, potassium persulfate-ferrous oxide, potassium persulfate-sodium bisulfite, isopropyl hydrogen peroxide-ferrous chloride, etc.

[0030] In some specific embodiments, the copolymer of the amide monomer with the unsaturated sulfonic acid monomer, the cationic monomer, and the silane monomer is obtained by one-step solution polymerization:

[0031] Amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers are mixed with water to obtain a monomer solution; an initiator is mixed with water to obtain an initiator solution.

[0032] The monomer solution is heated to 50-65°C, and then an initiator solution is added to react for 2-4 hours, followed by holding at this temperature for 0.15-1 hour.

[0033] In some specific embodiments, the copolymer of the amide monomer with the unsaturated sulfonic acid monomer, the cationic monomer, and the silane monomer is obtained by a two-step solution polymerization method:

[0034] An amide monomer, an unsaturated sulfonic acid monomer, a cationic monomer, and a silane monomer are mixed with water to obtain a monomer solution.

[0035] The initiator is mixed with water to obtain an initiator solution, which is then divided into initiator solution A and initiator solution B of equal mass.

[0036] The monomer solution and initiator solution A are heated to 50-65°C and reacted for 2-8 hours. Then initiator solution B is added and reacted for 1-2 hours.

[0037] In some preferred embodiments, the water loss reducing agent comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, acrylamide, methacryloylpropyltrimethylammonium chloride, and γ-methacryloyloxypropyltrimethoxysilane.

[0038] In some preferred embodiments, the water loss reducing agent comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, acrylamide, methacryloylpropyltrimethylammonium chloride, dimethyldiallylammonium chloride, and γ-methacryloyloxypropyltrimethoxysilane.

[0039] In some preferred embodiments, the water loss reducing agent comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, sodium p-styrenesulfonate, acrylamide, methacryloylpropyltrimethylammonium chloride, and γ-methacryloyloxypropyltrimethoxysilane.

[0040] In some preferred embodiments, the water loss reducing agent comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, acrylamide, methacryloylpropyltrimethylammonium chloride, and vinyltriethoxysilane.

[0041] In some embodiments, the latex comprises a copolymer of styrene monomers, acrylate monomers, and unsaturated sulfonic acid monomers.

[0042] In some embodiments, the acrylate monomers in the latex include one or more of methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, dodecyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, n-octyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, dodecyl acrylate, hexadecyl acrylate, octadecyl acrylate, n-octyl acrylate, and 2-ethylhexyl acrylate.

[0043] In some embodiments, the unsaturated sulfonic acid monomers in the latex include at least one of acrylamide sulfonic acid, ethylene sulfonic acid, styrene sulfonic acid, propylene sulfonic acid, methpropylene sulfonic acid, or salts thereof; preferably, at least one of 2-acrylamido-2-methylpropanesulfonic acid, sodium styrene sulfonate, sodium propylene sulfonate, sodium methpropylene sulfonate, sodium 3-allyloxy-2-hydroxy-1-propanesulfonate, and sodium vinylbenzene sulfonate.

[0044] In some embodiments, the copolymer of the styrene monomer with acrylate monomers and unsaturated sulfonic acid monomers is obtained by emulsion polymerization. In some specific embodiments, the preparation of the copolymer of the styrene monomer with acrylate monomers and unsaturated sulfonic acid monomers includes the following steps:

[0045] The styrene monomer, acrylate monomer, unsaturated sulfonic acid monomer, emulsifier, and water are mixed and polymerized in the presence of an initiator. Preferably, the polymerization temperature is 60°C to 90°C. Preferably, the polymerization time is 2 to 8 hours. Preferably, the mass ratio of the total mass of the styrene monomer and acrylate monomer to the mass of the unsaturated sulfonic acid monomer is (85 to 95):(5 to 15). Preferably, the initiator accounts for 0.1 to 2% of the total mass of the styrene monomer, acrylate monomer, and unsaturated sulfonic acid monomer. Preferably, the emulsifier accounts for 0.2 to 5% of the total mass of the styrene monomer, acrylate monomer, and unsaturated sulfonic acid monomer. Preferably, the initiator comprises one or more of persulfate, peroxide, water-soluble azo initiator, and redox initiator, and more preferably one or more of ammonium persulfate, potassium persulfate, sodium persulfate, azobisisobutylamidine hydrochloride, azobisisobutylimidazoline hydrochloride, azodicyanovalerate, hydrogen peroxide-ferrous oxide, potassium persulfate-ferrous oxide, potassium persulfate-sodium bisulfite, and isopropyl hydrogen peroxide-ferrous chloride. Preferably, the emulsifier comprises at least one of anionic surfactant and nonionic surfactant, and more preferably at least one of sodium dodecyl sulfate, emulsifier OP-10 (a condensate of alkylphenol and ethylene oxide), MS-1 emulsifier, Onist2836, CO-436, CO-458, BASF Disponil FES 77, BASF Lutensol AT 18, Satter emulsifier (AY-5), and UCAN-1.

[0046] In some preferred embodiments, the latex comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, sodium p-styrenesulfonate, propyl acrylate, and styrene.

[0047] In some preferred embodiments, the latex comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, butyl acrylate, and styrene.

[0048] In some preferred embodiments, the latex comprises a copolymer of 2-acrylamide-2-methylpropanesulfonic acid, sodium p-styrenesulfonate, butyl acrylate, and styrene.

[0049] In some embodiments, the mass ratio of the retarder to the water loss reducing agent in the composition is (0.5-6):(2-12).

[0050] In some embodiments, the mass ratio of the retarder to the water loss reducer in the composition is 1:(0.3 to 24), for example 1:0.3, 1:0.5, 1:0.8, 1:1, 1:5, 1:10, 1:15, 1:20, 1:22, 1:24 or any value between them.

[0051] In some embodiments, the mass ratio of the retarder to the latex in the composition is (0.5-6):(3-20).

[0052] In some embodiments, the mass ratio of the retarder to the latex in the composition is 1:(0.5 to 40), for example 1:0.5, 1:0.8, 1:1, 1:5, 1:10, 1:15, 1:20, 1:25, 1:30, 1:35, 1:40 or any value between them.

[0053] In some embodiments, the mass ratio of the first retarder to the second retarder is 1:(0.2 to 3.5), for example 1:0.3, 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5 or any value between them, preferably 1:(0.2 to 1.5).

[0054] In a second aspect, the present invention provides a cement slurry comprising a cementitious material and the admixture composition described in the first aspect of the present invention, wherein the cementitious material comprises aluminate cement.

[0055] In some embodiments, the cementitious material further includes at least one of fly ash, silica fume, phosphate, and polyphosphate.

[0056] In some preferred embodiments, the cementitious material includes aluminate cement, fly ash, silica fume, phosphate, and polyphosphate.

[0057] In some embodiments, the admixture composition accounts for 5.5% to 38% of the mass of the aluminate cement, for example, 6%, 9%, 12%, 15%, 20%, 22%, 25%, 28%, 30%, 35%, 38% or any value between therewith, preferably 9% to 25%.

[0058] In some embodiments, the retarder in the admixture composition accounts for 0.5% to 6% of the mass of the aluminate cement, for example, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6% or any value between them, preferably 2% to 5%.

[0059] In some embodiments, the water loss reducing agent in the admixture composition accounts for 2 to 12% of the mass of the aluminate cement, for example, 2%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12% or any value between them, preferably 4% to 10%.

[0060] In some embodiments, the latex in the admixture composition accounts for 3 to 20% of the mass of the aluminate cement, for example, 3%, 3.5%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 18%, 20% or any value between therewith, preferably 3 to 10%, more preferably 4 to 6%.

[0061] Thirdly, the present invention provides the application of the additive composition described in the first aspect or the cement slurry described in the second aspect in cementing.

[0062] The cementing described in this invention includes oil well cementing and carbon sequestration cementing.

[0063] Compared with the prior art, the admixture composition of the present invention uses a combination of small molecule retarders of hydroxycarboxylic acid and copolymers of unsaturated sulfonic acid monomers, unsaturated carboxylic acid monomers, and cationic monomers as high molecular weight retarders. This can ensure that the thickening time of the cementitious material, especially the aluminate cement paste, is adjustable within 3 to 7 hours in the range of 60 to 120°C. Furthermore, by selecting copolymers of amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers as water loss reducing agents, and adding copolymers of styrene monomers, acrylate monomers, and unsaturated sulfonic acid monomers as latex agents, the water loss of the cementitious material, especially the aluminate cement paste, can meet the working requirements while ensuring that the cement paste does not crack under hydrothermal conditions. Attached Figure Description

[0064] Figure 1 The cracking of cement paste under hydrothermal conditions is shown for different latexes and dosages. Figure a corresponds to 5% Bath S400 latex; Figure b corresponds to 5% Bath 7623 latex; Figure c corresponds to 5% L1; Figure d corresponds to 5% L2; Figure e corresponds to 5% L3; Figure f corresponds to 4% L1; Figure g corresponds to 4% L2; and Figure h corresponds to 2% L2 and 3% L3. Detailed Implementation

[0065] 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 and accompanying drawings. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way.

[0066] In one specific embodiment of the present invention, the preparation of the second retarder in the admixture composition includes the following steps:

[0067] Solution A is prepared by dissolving sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer in water;

[0068] The reducing agent and chain transfer agent are dissolved in water to prepare solution B;

[0069] Add 5-20% solution A as the base material to the reactor, stir and heat to 40-80℃, add the initiator, and then add the remaining solution A and solution B dropwise to the reactor. The dropwise addition time for solution A is X hours, and the dropwise addition time for solution B is X + (0.5-1) hours, where X is 2-4. After the dropwise addition is complete, keep the temperature constant and continue the reaction for 0.5-2 hours to obtain a copolymer of unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer (polymer retarder).

[0070] As a specific embodiment of the present invention, the water loss reducing agent in the admixture composition is obtained by one-step solution polymerization:

[0071] Amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers are dissolved in water, and the pH is adjusted to neutral to obtain a monomer solution. An initiator is dissolved in water to obtain an initiator solution. All monomer solutions are added to a three-necked flask, the temperature is raised to 50-65°C, and the initiator solution is added dropwise for 2-4 hours. After maintaining the temperature for 0.15-1 hour, a dehydration reducing agent is obtained.

[0072] As a specific embodiment of the present invention, the water loss reducing agent in the admixture composition is obtained by a two-step solution polymerization method:

[0073] Amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers are dissolved in water, and the pH is adjusted to neutral to obtain a monomer solution. An initiator is dissolved in water to obtain an initiator solution, which is divided into two equal portions: initiator solution A and initiator solution B. 5–20% of the total mass of the monomer solution and 5–20% of the total mass of initiator solution A are added as base material to a three-necked flask. The temperature is raised to 50–65°C, and then all remaining monomer solution and all remaining initiator solution A are added dropwise. The monomer addition time is X hours, and the initiator solution A addition time is x + 0.5–1 hours, where X ranges from 2 to 6. After the addition is complete, the temperature is maintained for 0.5 hours. Then, initiator solution B is added dropwise over 1–2 hours to obtain a dehydration reducing agent.

[0074] In one specific embodiment of the present invention, the latex is obtained by emulsion polymerization:

[0075] Mix water and a portion of the emulsifier to obtain the base material;

[0076] The styrene monomer, acrylate monomer, unsaturated sulfonic acid monomer, emulsifier and water are mixed to obtain a pre-emulsion;

[0077] The initiator was mixed with water to obtain an initiation solution with a mass concentration greater than 0 wt% and less than or equal to 1 wt%.

[0078] Add the base material to a three-necked flask, heat to 60℃~90℃, add 5%~20% of the total mass of the pre-emulsion and 5%~20% of the total mass of the initiator to the three-necked flask, react for 10~30 min to obtain the pre-reaction solution;

[0079] Add the remaining pre-emulsion and the remaining initiator droplets to the pre-reaction solution. After the addition is complete, keep warm for 0.5 to 1 hour, cool to room temperature, and adjust the pH value to 7 to 9 to obtain the emulsion.

[0080] The remaining pre-emulsion and the remaining initiator droplets are added to the pre-reaction solution. The addition time of the pre-emulsion is X hours, and the addition time of the initiator is 0.5 to 1 hour longer than that of the pre-emulsion. The value of X ranges from 2 to 6.

[0081] Unless otherwise specified, all reagents used below are commercially available.

[0082] Preparation Example 1-1: Polymer Retarder R1

[0083] Weigh 48.65g of acrylic acid, 70g of 2-acrylamide-2-methylpropanesulfonic acid, and 37.16g of methacrylamide-propyltrimethylammonium chloride, and dissolve them in 100g of water to prepare monomer solution A. Add 5% of monomer solution A as a base to the reactor; heat to 60℃. Weigh 2.68g of 30% hydrogen peroxide and 5g of water, and add them to the reactor. Weigh 1.07g of vitamin C and 2.51g of mercaptopropionic acid, and dissolve them in 130g of water to prepare solution B. Add the remaining solution A and solution B dropwise to the reactor separately using a peristaltic pump. Solution A is added dropwise over 3 hours, and solution B over 3.5 hours. After the addition is complete, maintain the temperature for 1 hour to obtain polymeric retarder R1.

[0084] Preparation Examples 1-2: Polymer Retarder R2

[0085] Weigh 67.22g of maleic acid, 60g of 2-acrylamide-2-methylpropanesulfonic acid, and 50.97g of methacrylamide-propyltrimethylammonium chloride, and dissolve them in 100g of water to prepare monomer solution A. Add 10% of monomer solution A as a base to the reactor; heat to 60℃. Weigh 2.49g of 30% hydrogen peroxide and 5g of water, and add them to the reactor. Weigh 1.1g of vitamin C and 2.34g of mercaptopropionic acid, and dissolve them in 165g of water to prepare solution B. Add the remaining solution A and solution B dropwise to the reactor separately using a peristaltic pump. Solution A is added dropwise over 3.5 hours, and solution B over 4 hours. After the addition is complete, maintain the temperature for 1 hour to obtain the polymeric retarder R2.

[0086] Preparation Examples 1-3: Polymer Retarder R3

[0087] Weigh 94.11g of itaconic acid, 50g of 2-acrylamide-2-methylpropanesulfonic acid, 26.54g of methacrylpropyltrimethylammonium chloride, and 7.82g of dimethyldiallylammonium chloride, and dissolve them in 130g of water to prepare monomer solution A. Add 12% monomer solution A as the base material to the reactor; heat to 65℃. Weigh 2.46g of 30% hydrogen peroxide and 5g of water, and add them to the reactor. Weigh 0.98g of vitamin C and 2.30g of mercaptopropionic acid, and dissolve them in 130g of water to prepare solution B. Add the remaining solution A and solution B dropwise to the reactor separately using a peristaltic pump. Solution A is added dropwise over 3.5 hours, and solution B over 4 hours. After the addition is complete, maintain the temperature for 1 hour to obtain the polymeric retarder R3.

[0088] Preparation Examples 1-4: Polymer Retarder R4

[0089] Weigh 78.29g of acrylic acid, 35g of 2-acrylamide-2-methylpropanesulfonic acid, 10g of sodium p-styrenesulfonate, and 43.06g of methacrylamide-propyltrimethylammonium chloride, and dissolve them in 120g of water to prepare monomer solution A. Add 10% of monomer solution A as a base to the reactor; heat to 70℃. Weigh 3.40g of 30% hydrogen peroxide and 5g of water, and add them to the reactor. Weigh 1.36g of vitamin C and 2.89g of mercaptopropionic acid, and dissolve them in 125g of water to prepare solution B. Add the remaining solution A and solution B dropwise to the reactor separately using a peristaltic pump. Add solution A for 3 hours and solution B for 4 hours. After the addition is complete, maintain the temperature for 0.5 hours to obtain polymeric retarder R4.

[0090] Preparation Example 2-1: Water Loss Reducing Agent F1

[0091] Weigh 30g of acrylamide, 17.5g of 2-acrylamido-2-methylpropanesulfonic acid, 18.6g of methacryloylpropyltrimethylammonium chloride, and 1.0g of γ-methacryloyloxypropyltrimethoxysilane, and dissolve them in 200g of water, adjusting the pH to neutral. Add all of the above monomer solutions to a reaction vessel and heat to 60℃. Weigh 0.15g of ammonium persulfate, dissolve it in 50g of water, and add it dropwise to the reaction vessel using a peristaltic pump over 3 hours. After the addition is complete, maintain the temperature for 1 hour to obtain the dehydration reducing agent F1.

[0092] Preparation Example 2-2: Water Loss Reducing Agent F2

[0093] Weigh 30g of acrylamide, 17.5g of 2-acrylamido-2-methylpropanesulfonic acid, 27.9g of methacryloylpropyltrimethylammonium chloride, and 1.0g of γ-methacryloyloxypropyltrimethoxysilane, and dissolve them in 250g of water, adjusting the pH to neutral. Add all of the above monomer solutions to a reaction vessel and heat to 65℃. Weigh 0.21g of sodium persulfate, dissolve it in 50g of water, and add it dropwise to the reaction vessel using a peristaltic pump over 3.5 hours. After the addition is complete, maintain the temperature for 1 hour to obtain the dehydration reducing agent F2.

[0094] Preparation Example 2-3: Water Loss Reducing Agent F3

[0095] Weigh 25g of acrylamide, 21.7g of 2-acrylamido-2-methylpropanesulfonic acid, 31g of methacryloylpropyltrimethylammonium chloride, 22.8g of dimethyldiallylammonium chloride, and 1.7g of γ-methacryloyloxypropyltrimethoxysilane, and dissolve them in 350g of water, adjusting the pH to neutral. Add all of the above monomer solutions to a reaction vessel and heat to 65℃. Weigh 0.22g of ammonium persulfate, dissolve it in 50g of water, and add it dropwise to the reaction vessel using a peristaltic pump over 3 hours. After the addition is complete, maintain the temperature for 1 hour to obtain the dehydration reducer F3.

[0096] Preparation Example 2-4: Water Loss Reducing Agent F4

[0097] Weigh 20g of acrylamide, 15g of N,N-dimethylacrylamide, 53.8g of 2-acrylamido-2-methylpropanesulfonic acid, 5g of sodium p-styrenesulfonate, 38.1g of methacryloxypropyltrimethylammonium chloride, and 1.1g of γ-methacryloxypropyltrimethoxysilane, and dissolve them in 350g of water, adjusting the pH to neutral to prepare a monomer solution. Weigh 0.17g of ammonium persulfate and dissolve it in 60g of water to prepare initiator solution A. Add 20% of the monomer solution and 20% of initiator solution A to the reactor and heat to 60℃. Add the remaining monomer solution and initiator solution A dropwise using a peristaltic pump, adding the monomer solution dropwise over 3 hours and the initiator solution dropwise over 3.5 hours. After the addition is complete, maintain the temperature for 0.5 hours. Weigh 0.17g of ammonium persulfate and dissolve it in 60g of water to prepare initiator solution B, and add the initiator solution dropwise to the reactor over 1 hour. The water loss reducing agent F4 was obtained.

[0098] Preparation Example 2-5: Water Loss Reducing Agent F5

[0099] Weigh 15g of acrylamide, 15g of N,N-dimethylacrylamide, 37.5g of 2-acrylamido-2-methylpropanesulfonic acid, 38.1g of methacrylpropyltrimethylammonium chloride, and 0.9g of vinyltriethoxysilane, and dissolve them in 330g of water, adjusting the pH to neutral to prepare a monomer solution. Weigh 0.16g of sodium persulfate and dissolve it in 50g of water to prepare initiator solution A. Add 15% of the monomer solution and 15% of the initiator solution A to the reactor and heat to 70℃. Add the remaining monomer solution and initiator solution A dropwise using a peristaltic pump, adding the monomer solution dropwise over 3 hours. Add the initiator solution dropwise over 3 hours. After the addition is complete, maintain the temperature for 1 hour. Weigh 0.16g of sodium persulfate and dissolve it in 50g of water to prepare initiator solution B, and add the initiator solution dropwise to the reactor over 1 hour. The dehydration reducing agent F5 is obtained.

[0100] Preparation Example 3-1: Latex L1

[0101] Weigh 0.72g of BASF emulsifier Disponil FES 77, 0.22g of BASF emulsifier Lutensol AT 18, and 0.2g of emulsifier OP-10, mix with 24g of water, and add to the reactor as the base material. Heat to 80℃. Weigh 1.4g of 2-acrylamide-2-methylpropanesulfonic acid and 1.4g of sodium p-styrene sulfonate, dissolve in 30g of water, and add 1.75g ​​of BASF emulsifier Disponil FES 77 and 1.8g of BASF emulsifier Lutensol AT 18. Then, while stirring, slowly add 24g of styrene and 44g of propyl acrylate to form a pre-emulsion. Weigh 0.4g of sodium persulfate and dissolve in 50g of water to form an initiator solution. Add 20% of the pre-emulsion and 20% of the initiator solution to the reactor and pre-react for 20 minutes. The remaining pre-emulsion and initiator solution were added dropwise to the reactor separately. The pre-emulsion was added dropwise over 4 hours, and the initiator solution over 4.5 hours. After the addition was complete, the mixture was kept at the desired temperature for 1 hour, then cooled. After cooling to room temperature, the pH was adjusted to 7–9 to obtain latex L1.

[0102] Preparation Example 3-2: Latex L2

[0103] Weigh 1.87g of AY-5 emulsifier, 3.6g of UCAN-1, and 0.34g of OP-10 emulsifier, mix with 40g of water, and add to the reactor as the base material. Heat to 85℃. Weigh 7.2g of 2-acrylamide-2-methylpropanesulfonic acid, dissolve in 60g of water, and add 2.5g of CO-458 emulsifier and 1.5g of TX50 emulsifier. Then, while stirring, slowly add 40g of styrene and 74g of butyl acrylate to form a pre-emulsion. Weigh 0.91g of potassium persulfate and dissolve in 70g of water to form an initiator solution. Add 15% of the pre-emulsion and 20% of the initiator solution to the reactor and pre-react for 30 minutes. Add the remaining pre-emulsion and initiator solution dropwise to the reactor separately, with the pre-emulsion added over 3 hours and the initiator solution over 4 hours. After the addition is complete, maintain the temperature for 1 hour and then cool down. After cooling to room temperature, the pH is adjusted to 7-9 to obtain latex L2.

[0104] Preparation Example 3-3: Latex L3

[0105] Weigh 1.87g of AY-5 emulsifier, mix 3.6g of UCAN-1 with 40g of water, and add the mixture to the reactor as a base material. Heat to 90℃. Weigh 9.6g of 2-acrylamide-2-methylpropanesulfonic acid and 2g of sodium p-styrene sulfonate, dissolve in 55g of water, and add 3g of BASF emulsifier Disponil FES 77 and 3g of BASF emulsifier Lutensol AT 18. Then, while stirring, slowly add 30g of styrene and 80g of butyl acrylate to form a pre-emulsion. Weigh 0.95g of sodium persulfate and dissolve in 80g of water to form an initiator solution. Add 10% of the pre-emulsion and 15% of the initiator solution to the reactor and pre-react for 20 minutes. Add the remaining pre-emulsion and initiator solution dropwise to the reactor separately, with the pre-emulsion added over 4 hours and the initiator solution over 4.5 hours. After the addition is complete, maintain the temperature for 1 hour and then cool down. After cooling to room temperature, the pH is adjusted to 7-9 to obtain latex L3.

[0106] (I) Effects of different retarder on the thickening time of aluminate cement slurry

[0107] The polymeric retarder prepared above was combined with small molecular retarders such as malic acid, citric acid, and tartaric acid, and then added to the phosphate-modified aluminate cement system at different dosages (referring to the mass percentage of the retarder in aluminate cement CA50, see Table 1 for details). At the same time, commercially available small molecular retarders such as boric acid and borax were used as comparisons to test the thickening time.

[0108] The phosphate-modified aluminate cement slurry formula used is: aluminate cement (CA50) + fly ash + silica fume + sodium polyphosphate, wherein the amount of fly ash and silica fume is 20% and 4% of the mass of aluminate cement, respectively, and the amount of sodium polyphosphate is 5% or 10% of the mass of aluminate cement; the slurry density reaches 1.85-2.05 g / cm3.

[0109] The test conditions and results are shown in Table 1.

[0110] Table 1

[0111]

[0112]

[0113] As shown in Table 1, the effects of using boric acid, borax, malic acid, citric acid, and other small-molecule retarders alone on the thickening time of aluminate cement slurry are very limited. Increasing the dosage of boric acid and borax to 6% results in the cement slurry thickening within 60 minutes. At lower temperatures (60-80℃), the addition of citric acid alone has a certain effect on prolonging the thickening time of the slurry, but as the temperature increases (120℃), the effect of citric acid alone on delaying the thickening time decreases sharply.

[0114] By using a combination of small-molecule and high-molecular-weight retarders, the thickening time can be adjusted from 3 to 7 hours within the temperature range of 60–120℃. Among these, the combination of citric acid with high-molecular-weight retarder R4 and malic acid with high-molecular-weight retarder R4 shows particularly significant advantages.

[0115] (II) Effects of different water loss reducing agents on water loss of aluminate cement slurry

[0116] The water loss reducing agent prepared above was added to the phosphate modified aluminate cement system at different dosages (referring to the mass percentage of the water loss reducing agent in aluminate cement CA50, see Table 2 for details). At the same time, commercially available water loss reducing agents such as hydroxycellulose ether and montmorillonite were used as comparisons to test their gas channeling time and water loss.

[0117] The phosphate-modified aluminate cement slurry formula used is: aluminate cement (CA50) + fly ash + silica fume + sodium polyphosphate, wherein the admixtures of fly ash, silica fume and sodium polyphosphate are 20%, 4% and 10% of the mass of aluminate cement, respectively; the slurry density reaches 1.85-2.05 g / cm3.

[0118] In addition, the retarders added to the phosphate-modified aluminate cement system are: a combination of citric acid and polymeric retarder R1 (with dosages of 2% and 1% of the aluminate cement mass, respectively); or a combination of malic acid and polymeric retarder R2 (with dosages of 2% and 3% of the aluminate cement mass, respectively).

[0119] The test conditions and results are shown in Table 2.

[0120] Table 2

[0121]

[0122]

[0123] As can be seen from Table 2, commercially available water loss control agents such as hydroxycellulose ether, montmorillonite, and 2-acrylamide-2-methylpropanesulfonic acid copolymer with acrylamide cannot control water loss in phosphate-modified calcium aluminate cement systems, and the slurry gas migrates within minutes.

[0124] The fluid loss control agents F1 to F5 of this application have a good effect on controlling fluid loss. At 60 to 120°C, no gas channeling occurred in phosphate-modified calcium aluminate cement slurry of different systems within 30 minutes, and the API fluid loss was controlled within 50 mL, which meets the cementing requirements.

[0125] (III) The Influence of Different Latexes on the Crack Resistance of Aluminate Cement Grout

[0126] The prepared latex was added to the phosphate-modified aluminate cement system at different dosages (referring to the mass percentage of latex in aluminate cement CA50, see Table 3 for details). At the same time, commercially available latexes such as Bass S400 latex and Bass 7623 latex were used as comparisons to test whether they cracked after being soaked in hydrothermal conditions (60℃) for 7 days.

[0127] The formula for the phosphate-modified aluminate cement slurry used is: aluminate cement (CA50) + fly ash + silica fume + sodium polyphosphate, wherein the admixtures of fly ash, silica fume and sodium polyphosphate are 20%, 4% and 5% of the mass of aluminate cement, respectively; the slurry density reaches 1.85-2.05 g / cm3.

[0128] In addition, the retarder added to the phosphate-modified aluminate cement system is a combination of citric acid and polymeric retarder R1 (with dosages of 2% and 1% of the aluminate cement mass, respectively); the water loss reducing agent added is F1, with a dosage of 5% of the aluminate cement mass.

[0129] The test conditions and results are shown in Table 3 and Figure 1 .

[0130] Table 3

[0131]

[0132] From Table 3 and Figure 1 It can be seen that the addition of commercially available Bath S400 latex and Bath 7623 latex leads to significant cracking of the slurry (see...). Figure 1 a and Figure 1 b) The latexes L1 to L3 prepared in this invention, used alone or in combination, can significantly improve the crack resistance and toughness of the slurry. No cracking was observed after immersion in hydrothermal conditions (60°C) for 7 days (see [link]). Figure 1 c to Figure 1 h).

[0133] (iv) The effect of composite admixtures on the overall performance of aluminate cement slurry

[0134] The polymeric retarder prepared above was compounded with small-molecule retarders such as citric acid and malic acid, and then combined with the water loss reducing agent and the latex prepared above. These were added as composite admixtures to phosphate-modified aluminate cement systems, and tests were conducted on thickening time, API water loss, and whether the cement blocks cracked under hydrothermal conditions. The types of retarder, water loss reducing agent, and latex in the composite admixture, and their dosages in the cement (percentage by mass of cement), are shown in Table 4.

[0135] The formula for the phosphate-modified aluminate cement slurry used is: aluminate cement (CA50) + fly ash + silica fume + sodium polyphosphate, wherein the admixtures of fly ash, silica fume and sodium polyphosphate are 20%, 4% and 5% of the mass of aluminate cement, respectively; the slurry density reaches 1.85-2.05 g / cm3.

[0136] The test conditions and results are shown in Table 4. The test standards refer to cementing requirements:

[0137] (1) Thickening time: BHCT≦150℃, within 20Mpa, adjustable from 3 to 7Hr;

[0138] (3) API water loss: BHCT≦150℃, within 50mL;

[0139] (3) The cement block did not crack after being soaked in hydrothermal conditions (BHCT≦60℃) for 7 days.

[0140] Table 4

[0141]

[0142]

[0143] As can be seen from the test results in Table 4, the phosphate-modified calcium aluminate cement system obtained by using the composite admixtures in Comparative Examples 1-7 does not meet the requirements for thickening time and API water loss, and is prone to cracking under hydrothermal conditions.

[0144] The composite admixture composed of the retarder, water loss reducer and latex in Examples 1-7 can ensure that the thickening time and API water loss of the phosphate-modified calcium aluminate cement paste meet the working requirements, while ensuring that the paste does not crack under hydrothermal conditions.

[0145] 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. A cementitious material admixture composition for cementing, characterized in that, The cementitious material includes aluminate cement, and the admixture composition includes a retarder, a water loss reducer, and a latex. The retarder includes a first retarder and a second retarder. The first retarder includes hydroxycarboxylic acid and / or hydroxycarboxylate salts, and the second retarder includes unsaturated sulfonic acid monomers, copolymers of unsaturated carboxylic acid monomers and cationic monomers. The water loss reducing agent comprises copolymers of amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers; The latex comprises a copolymer of styrene monomers, acrylate monomers, and unsaturated sulfonic acid monomers; The cationic monomers include quaternary ammonium salt cationic monomers.

2. The admixture composition according to claim 1, characterized in that, The first retarder comprises C2-C10 hydroxy fatty acids and / or C2-C10 hydroxy fatty acid salts; and / or, The unsaturated sulfonic acid monomer includes at least one of acrylamide sulfonic acid, ethylene sulfonic acid, styrene sulfonic acid, propylene sulfonic acid, methpropylene sulfonic acid, or a salt thereof; and / or, The unsaturated carboxylic acid monomer includes C2-C10 mono- or di-unsaturated carboxylic acids; and / or, The cationic monomer includes at least one of methacryloylpropyltrimethylammonium chloride, methacryloyloxyethyltrimethylammonium chloride, and dimethyldiallylammonium chloride.

3. The admixture composition according to claim 2, characterized in that, The first retarder includes at least one of gluconic acid, tartaric acid, citric acid, malic acid, and their salts; and / or The unsaturated carboxylic acid monomer includes C3-C8 mono- or di-unsaturated carboxylic acids; and / or The unsaturated sulfonic acid monomer includes at least one of 2-acrylamido-2-methylpropanesulfonic acid, sodium styrene sulfonate, sodium propylene sulfonate, sodium methpropylene sulfonate, sodium 3-allyloxy-2-hydroxy-1-propanesulfonate, and sodium vinylbenzene sulfonate; and / or The cationic monomers include methacryloylpropyltrimethylammonium chloride and / or dimethyldiallylammonium chloride.

4. The admixture composition according to claim 2, characterized in that, The unsaturated sulfonic acid monomer comprises 2-acrylamido-2-methylpropanesulfonic acid and / or sodium styrene sulfonate; and / or The unsaturated carboxylic acid monomer includes at least one of acrylic acid, maleic acid, and itaconic acid.

5. The admixture composition according to claim 1, characterized in that, The copolymer of the unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer is obtained by solution polymerization.

6. The admixture composition according to claim 5, characterized in that, The solution polymerization includes the following steps: The unsaturated sulfonic acid monomer, unsaturated carboxylic acid monomer, and cationic monomer are polymerized in a solvent in the presence of a reducing agent, an initiator, and a chain transfer agent.

7. The admixture composition according to claim 6, characterized in that, The solvent is water.

8. The admixture composition according to claim 6, characterized in that, The molar ratio of the unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer is 1:(1~10):(0.2~1.5).

9. The admixture composition according to claim 6, characterized in that, The molar ratio of the initiator to the total molar ratio of the unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer is (0.005~0.1):

1.

10. The admixture composition according to claim 6, characterized in that, The molar ratio of the chain transfer agent to the total molar ratio of the unsaturated sulfonic acid monomer, the unsaturated carboxylic acid monomer, and the cationic monomer is (0.01~0.2):

1.

11. The admixture composition according to claim 6, characterized in that, The molar ratio of the initiator to the reducing agent is (1~5):

1.

12. The admixture composition according to claim 1, characterized in that, The amide monomers include acrylamide monomers.

13. The admixture composition according to claim 1, characterized in that, The amide monomers include acrylamide and / or N,N-dimethylacrylamide.

14. The admixture composition according to claim 1, characterized in that, The silane monomer includes at least one of vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(β-methoxyethoxy)silane, and γ-methacryloyloxypropyltrimethoxysilane.

15. The admixture composition according to claim 1, characterized in that, The silane monomers include γ-methacryloxypropyltrimethoxysilane and / or vinyltriethoxysilane.

16. The admixture composition according to claim 1, characterized in that, The copolymer of the amide monomer, unsaturated sulfonic acid monomer, cationic monomer, and silane monomer is obtained by solution polymerization.

17. The admixture composition according to claim 16, characterized in that, The solution polymerization includes the following steps: The amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers are polymerized in a solvent in the presence of an initiator.

18. The admixture composition according to claim 17, characterized in that, The solvent is water.

19. The admixture composition according to claim 17, characterized in that, The molar ratio of the amide monomer, unsaturated sulfonic acid monomer, cationic monomer to silane monomer is 1:(0.1~0.5):(0.2~0.8):(0.01~0.02).

20. The admixture composition according to claim 17, characterized in that, The initiator accounts for 0.1% to 0.4% of the total mass of the amide monomers, unsaturated sulfonic acid monomers, cationic monomers, and silane monomers.

21. The admixture composition according to claim 1, characterized in that, The acrylate monomers include one or more of the following: methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, dodecyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, n-octyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, dodecyl acrylate, hexadecyl acrylate, octadecyl acrylate, n-octyl acrylate, and 2-ethylhexyl acrylate.

22. The admixture composition according to claim 1, characterized in that, The acrylate monomers include propyl acrylate or butyl acrylate.

23. The admixture composition according to claim 1, characterized in that, The copolymer of styrene monomer, acrylate monomer, and unsaturated sulfonic acid monomer is obtained by emulsion polymerization.

24. The admixture composition according to claim 23, characterized in that, The emulsion polymerization includes the following steps: The styrene monomer, acrylate monomer, unsaturated sulfonic acid monomer, emulsifier and water are mixed and polymerized in the presence of an initiator.

25. The admixture composition according to claim 24, characterized in that, The total mass ratio of the styrene monomer and acrylate monomer to the unsaturated sulfonic acid monomer is (85~95):(5~15).

26. The admixture composition according to claim 24, characterized in that, The initiator accounts for 0.1% to 2% of the total mass of the styrene monomer, acrylate monomer, and unsaturated sulfonic acid monomer.

27. The admixture composition according to claim 24, characterized in that, The emulsifier accounts for 0.2% to 5% of the total mass of the styrene monomer, acrylate monomer, and unsaturated sulfonic acid monomer.

28. The admixture composition according to any one of claims 1-27, characterized in that, The mass ratio of the retarder to the water loss reducing agent is 1:(0.3~24); and / or, the mass ratio of the retarder to the latex is 1:(0.5~40).

29. The admixture composition according to any one of claims 1-27, characterized in that, In the retarder, the mass ratio of the first retarder to the second retarder is 1:(0.2~3.5).

30. The admixture composition according to claim 29, characterized in that, In the retarder, the mass ratio of the first retarder to the second retarder is 1:(0.2~1.5).

31. The admixture composition according to any one of claims 1-27, characterized in that, The first retarder includes citric acid and / or malic acid, and the second retarder includes at least one of the following: a copolymer of 2-acrylamide-2-methylpropanesulfonic acid with acrylic acid and methacryloylpropyltrimethylammonium chloride; a copolymer of 2-acrylamide-2-methylpropanesulfonic acid with sodium p-styrenesulfonate and acrylic acid and methacryloylpropyltrimethylammonium chloride; and a copolymer of itaconic acid with 2-acrylamide-2-methylpropanesulfonic acid, methacryloylpropyltrimethylammonium chloride, and dimethyldiallylammonium chloride.

32. A cement slurry comprising a cementitious material and an admixture composition according to any one of claims 1 to 31, wherein the cementitious material comprises aluminate cement.

33. The cement slurry according to claim 32, characterized in that, The cementing material also includes at least one of fly ash, silica fume, phosphate, and polyphosphate.

34. The cement slurry according to claim 32 or 33, characterized in that, The admixture composition accounts for 5.5% to 38% of the mass of the aluminate cement.

35. The cement slurry according to claim 34, characterized in that, The admixture composition accounts for 9% to 25% of the mass of the aluminate cement.

36. The cement slurry according to claim 32 or 33, characterized in that, The retarder accounts for 1% to 6% of the mass of the aluminate cement.

37. The cement slurry according to claim 36, characterized in that, The retarder accounts for 2% to 5% of the mass of the aluminate cement.

38. The cement slurry according to claim 32 or 33, characterized in that, The water loss reducing agent accounts for 2% to 12% of the mass of the aluminate cement.

39. The cement slurry according to claim 38, characterized in that, The water loss reducing agent accounts for 4% to 10% of the mass of the aluminate cement.

40. The cement slurry according to claim 32 or 33, characterized in that, The latex accounts for 3% to 20% of the mass of the aluminate cement.

41. The cement slurry according to claim 40, characterized in that, The latex accounts for 3% to 10% of the mass of the aluminate cement.

42. The use of the admixture composition according to any one of claims 1-31 or the cement slurry according to any one of claims 32-41 in cementing.

43. The application according to claim 42, characterized in that, The cementing includes oil well cementing and carbon sequestration cementing.

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