A cement activity enhancer and its preparation method

Abstract

The present invention discloses a cement activity enhancer and a preparation method thereof, belonging to the technical field of cement additives. The enhancer of the present invention comprises the following raw materials in parts by weight: 10-20 parts of an alkanolamine component, 3-5 parts of urea, 1-3 parts of sucrose, 35-50 parts of inorganic salts, 5-10 parts of an activator, 3-7 parts of a water-reducing component, and 40-50 parts of water. The present invention adds a prepared activity activator to accelerate the formation of cement hydration products and improve the early strength; at the same time, adding sodium lauroyl glycinate can promote the uniform dispersion of hydration products in the system. After the promoter and sodium lauroyl glycinate are mixed in equal proportions, an obvious synergistic effect appears, and finally the purpose of reducing clinker and improving the early and late strengths is achieved. Under the combined action of the raw materials of the present invention, the clinker ratio is greatly reduced, and there is a good activation effect on fly ash-based active admixtures, and the comprehensive performance of the cement is effectively improved, having practical application value.

Description

Technical Field

[0001] The present invention belongs to the technical field of cement additives, and particularly relates to a cement activity enhancer and a preparation method thereof. Background Art

[0002] At present, the CO2 emission reduction measures adopted in the cement industry include three aspects: one is technical emission reduction, that is, CO2 emission reduction is carried out by improving the technical level of cement production process and using alternative fuels; the second is relative emission reduction, that is, CO2 emission reduction is carried out by establishing a carbon trading financial system; the third is production capacity replacement emission reduction, that is, CO2 emission reduction is carried out by eliminating production lines with backward equipment and high energy consumption.

[0003] At present, in actual production, auxiliary cementitious materials are generally used to reduce the addition of cement clinker. The specific measure is to increase the dosage of auxiliary cementitious materials such as fly ash and granulated blast furnace slag in cement. However, reducing the clinker and increasing the dosage of auxiliary materials such as fly ash will lead to a decrease in the early strength of cement due to too high dosage of auxiliary cementitious materials. Therefore, how to regulate the comprehensive performance of low-clinker gel materials is a technical problem to be solved urgently at present.

[0004] At present, to solve this problem, the prior art generally solves it by adding admixtures. For example, Chinese Patent Application CN201910119546.1 discloses a weakly accelerating early strength agent for oil well cement, and the early strength agent contains the following components: in parts by weight, 30-70 parts of nano materials, 20-50 parts of inorganic salts, 5-20 parts of organic salts, and 5-30 parts of drag reducing agents; wherein the nano materials are selected from the mixture of fibrous nano materials and flaky nano materials. Chinese Patent Application CN202110286365.5 discloses a preparation method of a crystal nucleus type early strength agent, which includes the following steps: a) mixing calcium oxide, sodium silicate and waste slurry water from a concrete mixing plant to obtain modified waste slurry water; b) mixing and grinding the modified waste water, lead-zinc smelting slag, dispersant and grinding aid to obtain a crystal nucleus type early strength agent; the dispersant includes naphthalene sulfonate, calcium lignosulfonate and magnesium lignosulfonate.

[0005] However, these current cement admixtures have a single function and complex components. When added to cement, although they can improve the early strength, they do not have a significant effect on improving other properties, and the cost is relatively high, so the practical application value is not great. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention provides a cement activation enhancer, which can significantly reduce the dosage of cement clinker, achieving the purpose of carbon reduction, cost reduction, efficiency increase and improvement of cement performance.

[0007] To achieve the above technical purpose, the technical solution adopted by the present invention is as follows:

[0008] A cement activity enhancer, comprising the following raw materials in parts by weight: 10-20 parts of an alkanolamine component, 3-5 parts of urea, 5-7 parts of sucrose, 35-50 parts of inorganic salt, 5-10 parts of an activator, 3-7 parts of a water-reducing component, and 40-50 parts of water.

[0009] Further, the alkanolamine component is one or more of triethanolamine, triisopropanolamine, and diethanolmonoisopropanolamine.

[0010] Furthermore, the alkanolamine component is diethanolmonoisopropanolamine.

[0011] Further, the inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0012] Further, the water-reducing component is one of a naphthalene-based water reducer or an aliphatic water reducer.

[0013] Further, the activator is obtained by mixing a promoter and sodium lauroyl glycinate in a mass ratio of 1:1.

[0014] Furthermore, the preparation method of the promoter is as follows:

[0015] (1) Add 80 g of EPEG to 300 g of water, and continuously stir until completely dissolved as the base material; form material A from 3 g of acrylic acid, 30 g of N,N-dimethylacrylamide, and 60 g of deionized water, and form material B from 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; add 1.6 g of hydrogen peroxide to the base material, continue stirring for 5 min, and then simultaneously dropwise add material A and material B, with the reaction temperature of 35-40 °C, the dropping time of material A being 50 min; the dropping time of material B being 55 min, and after the dropping is complete, keep warm for 3 h to obtain a dispersion:

[0016] (2) Add an appropriate amount of distilled water to the dispersion to obtain a dilution, and then simultaneously dropwise add an aqueous solution of calcium acetate and an aqueous solution of sodium silicate to the dilution, and continuously stir for 1 h to obtain the promoter.

[0017] Furthermore, in step (2), the volume ratio of the dispersion to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the dilution is 1:1:5; the molar concentrations of the aqueous solution of calcium acetate and the aqueous solution of sodium silicate are both 2 mol / L.

[0018] Furthermore, EPEG is ethylene glycol monovinyl polyethylene glycol ether, with a molecular weight of 3000-4000.

[0019] A preparation method of a cement activity enhancer, comprising the following preparation steps:

[0020] (1) Preparation of activator: First, prepare the accelerator, and then mix the accelerator and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator;

[0021] (2) Add water and inorganic salts by weight to a stirring container, maintain the temperature at 50 - 60 °C, stir for 10 - 20 minutes until the inorganic salts are completely dissolved, and the stirring speed is not less than 100 rpm;

[0022] (3) Sequentially add the alkanolamine component, urea, sucrose, activator, and water-reducing component to the stirring container, maintain the temperature at 50 - 60 °C, stir for 20 - 30 minutes, and the stirring speed is not less than 100 rpm. After stirring, filter and discharge to obtain the final product.

[0023] The dosage of the enhancer of the present invention is 0.1 - 0.5‰ of the mass of cement.

[0024] Beneficial effects:

[0025] (1) When the fly ash content is too high, it will cause a relative decrease in the cement content in the concrete and a decrease in the amount of hydration products, thus affecting the strength of the concrete. Therefore, in the present invention, the alkanolamine component, urea, inorganic salts, water-reducing component, and activation component are used in combination. Among them, the alkanolamine component can promote the primary and secondary hydration of C3S and C2S, thereby optimizing the pore structure;

[0026] (2) Prepare an active activator. First, prepare the accelerator. Using a polycarboxylate superplasticizer as the dispersing component and adding calcium salt and silicate components, the prepared active accelerator can play a nucleation role, provide a nucleation template for cement hydration, accelerate the cement hydration reaction, accelerate the formation of cement hydration products, and improve the early strength; at the same time, adding sodium lauroyl glycinate can promote the uniform dispersion of hydration products in the system. After the accelerator and sodium lauroyl glycinate are mixed in equal proportions, an obvious synergistic effect appears, and finally the purpose of reducing clinker and improving early and late strength is achieved;

[0027] (3) Add inorganic salt components. Calcium nitrate plays a role in promoting hardening and early strength and antifreeze. Sodium sulfate can improve the early strength of cement to a certain extent. Potassium alum and sucrose can adjust the setting time of cement, and at the same time enhance the adhesion between the cement paste and the aggregate, improving the overall performance of the concrete;

[0028] (4) Adding urea, urea reacts with the hardened cement stone to form substances such as calcium amine salts, improving the density and compressive performance of the concrete;

[0029] (5) In summary, under the combined action of the raw materials of the present invention, the clinker ratio is significantly reduced, the fly ash-based active admixture has good activation, the comprehensive performance of the cement is effectively improved, and it has practical application value. Description of the Drawings

[0030] Figure 1 Pore size distribution diagrams of the samples of Example 5, Comparative Examples 1-4, and the blank group after 7 days of hydration;

[0031] Figure 2 Scanning electron microscope images of the samples of Example 5 and Comparative Examples 1-4 of the present invention after 28 days of hydration. Detailed implementation mode

[0032] The technical solutions of the present invention will be further described below in conjunction with specific embodiments, but are not limited thereto.

[0033] Example 1

[0034] A cement activity enhancer, comprising the following raw materials in parts by weight: 10 parts of an alkanolamine component, 5 parts of urea, 5 parts of sucrose, 50 parts of inorganic salts, 5 parts of an activator, 7 parts of a water-reducing component, and 50 parts of water.

[0035] The alkanolamine component is triethanolamine.

[0036] The inorganic salts are obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0037] The water-reducing component is a naphthalene-based water reducer or.

[0038] The activator is obtained by mixing a promoter and sodium lauroyl glycinate in a mass ratio of 1:1.

[0039] The preparation method of the promoter is as follows:

[0040] (1) Add 80 g of EPEG to 300 g of water, and continuously stir until completely dissolved as the base material; A material is composed of 3 g of acrylic acid, 30 g of N,N-dimethylacrylamide, and 60 g of deionized water, and B material is composed of 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; add 1.6 g of hydrogen peroxide to the base material, continue to stir for 5 min, and then simultaneously dropwise add A material and B material, with the reaction temperature of 35-40 °C, the dropping time of A material being 50 min; the dropping time of B material being 55 min, and after dropping, keep warm for 3 h to obtain a dispersion:

[0041] (2) Add an appropriate amount of distilled water to the dispersion to obtain a dilution, and then simultaneously dropwise add the aqueous solution of calcium acetate and the aqueous solution of sodium silicate to the dilution, and continuously stir for 1 h to obtain the promoter.

[0042] In step (2), the volume ratio of the dispersion to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the dilution is 1:1:5; the molar concentrations of the aqueous solution of calcium acetate and the aqueous solution of sodium silicate are both 2 mol / L.

[0043] EPEG is ethylene glycol mono vinyl polyethylene glycol ether with a molecular weight of 3000 - 4000.

[0044] A preparation method of a cement activity enhancer includes the following preparation steps:

[0045] (1) Prepare the activator: First, prepare the accelerator, and then mix the accelerator and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator;

[0046] (2) Add water and inorganic salts by weight to a stirring container, keep the temperature at 50 - 60 °C, stir for 10 minutes to completely dissolve the inorganic salts, and the stirring speed is not less than 100 rpm;

[0047] (3) Sequentially add the alkanolamine component, urea, sucrose, activator, and water - reducing component to the stirring container, keep the temperature at 50 - 60 °C, stir for 20 minutes, and the stirring speed is not less than 100 rpm. After stirring is completed, filter and discharge to obtain the final product.

[0048] Example 2

[0049] A cement activity enhancer includes the following raw materials by weight: 12 parts of alkanolamine component, 4 parts of urea, 6 parts of sucrose, 35 parts of inorganic salts, 6 parts of activator, 4 parts of water - reducing component, and 45 parts of water.

[0050] The alkanolamine component is triisopropanolamine.

[0051] The inorganic salts are obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0052] The water - reducing component is an aliphatic water - reducing agent.

[0053] The activator is obtained by mixing the accelerator and sodium lauroyl glycinate in a mass ratio of 1:1.

[0054] The preparation method of the accelerator is as follows:

[0055] (1) Add 80 g of EPEG to 300 g of water, continuously stir until completely dissolved as the base material; A material consists of 3 g of acrylic acid, 30 g of N, N - dimethylacrylamide, and 60 g of deionized water, and B material consists of 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; Add 1.6 g of hydrogen peroxide to the base material, continue to stir for 5 min, and then simultaneously drop - add A material and B material. The reaction temperature is 35 - 40 °C, the dropping time of A material is 50 min; the dropping time of B material is 55 min. After dropping is completed, keep the temperature for 3 h to obtain the dispersion liquid:

[0056] (2) Add an appropriate amount of distilled water to the dispersion liquid to obtain a dilution liquid, and then simultaneously drop - add the aqueous solution of calcium acetate and the aqueous solution of sodium silicate to the dilution liquid, and continuously stir for 1 h to obtain the accelerator.

[0057] In step (2), the volume ratio of the dispersion liquid to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the diluent is 1:1:5; the molar concentration of both the aqueous solution of calcium acetate and the aqueous solution of sodium silicate is 2 mol / L.

[0058] EPEG is ethylene glycol mono vinyl polyethylene glycol ether with a molecular weight of 3000 - 4000.

[0059] A preparation method of a cement activity enhancer includes the following preparation steps:

[0060] (1) Prepare an activator: First, prepare a promoter, and then mix the promoter and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator;

[0061] (2) Add water and inorganic salts by weight parts to a stirring container, keep the temperature at 50 - 60 °C, stir for 20 minutes to completely dissolve the inorganic salts, and the stirring speed is not less than 100 rpm;

[0062] (3) Sequentially add the alkanolamine component, urea, sucrose, activator, and water - reducing component to the stirring container, keep the temperature at 50 - 60 °C, stir for 20 minutes, the stirring speed is not less than 100 rpm, and after stirring, filter and discharge to obtain the final product.

[0063] Example 3

[0064] A cement activity enhancer includes the following raw materials by weight parts: 15 parts of alkanolamine component, 3 parts of urea, 7 parts of sucrose, 40 parts of inorganic salts, 7 parts of activator, 5 parts of water - reducing component, and 42 parts of water.

[0065] The alkanolamine component is diethanol monoisopropanolamine.

[0066] The inorganic salts are obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0067] The water - reducing component is a naphthalene - based water - reducing agent.

[0068] The activator is obtained by mixing a promoter and sodium lauroyl glycinate in a mass ratio of 1:1.

[0069] The preparation method of the promoter is:

[0070] (1) Add 80 g of EPEG to 300 g of water, and continuously stir until it is completely dissolved to obtain the base material; compose Material A with 3 g of acrylic acid, 30 g of N,N-dimethylacrylamide, and 60 g of deionized water, and compose Material B with 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; add 1.6 g of hydrogen peroxide to the base material, continue to stir for 5 min, and then simultaneously drip Material A and Material B. The reaction temperature is 35 - 40 °C, the dripping time of Material A is 50 min; the dripping time of Material B is 55 min. After dripping is completed, keep warm for 3 h to obtain the dispersion:

[0071] (2) Add an appropriate amount of distilled water to the dispersion to obtain a dilution, and then simultaneously drip the aqueous solution of calcium acetate and the aqueous solution of sodium silicate into the dilution. After continuously stirring for 1 h, obtain the promoter.

[0072] In step (2), the volume ratio of the dispersion to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the dilution is 1:1:5; the molar concentrations of the aqueous solution of calcium acetate and the aqueous solution of sodium silicate are both 2 mol / L.

[0073] EPEG is ethylene glycol mono vinyl polyethylene glycol ether, with a molecular weight of 3000 - 4000.

[0074] A preparation method of a cement activity enhancer includes the following preparation steps:

[0075] (1) Prepare the activator: First prepare the promoter, and then mix the promoter and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator;

[0076] (2) Add water and inorganic salts by weight parts to the stirring container, keep the temperature at 50 - 60 °C, stir for 10 minutes to completely dissolve the inorganic salts, and the stirring speed is not less than 100 rpm;

[0077] (3) Sequentially add the alkanolamine component, urea, sucrose, activator, and water reducing component to the stirring container, keep the temperature at 50 - 60 °C, stir for 30 minutes, and the stirring speed is not less than 100 rpm. After stirring is completed, filter and discharge to obtain the final product.

[0078] Example 4

[0079] A cement activity enhancer includes the following raw materials by weight parts: 18 parts of alkanolamine component, 4 parts of urea, 6 parts of sucrose, 45 parts of inorganic salts, 9 parts of activator, 6 parts of water reducing component, and 48 parts of water.

[0080] The alkanolamine component is triethanolamine.

[0081] The inorganic salts are obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0082] The water-reducing component is a naphthalene-based water reducer or...

[0083] The activator is obtained by mixing a promoter and sodium lauroyl glycinate in a mass ratio of 1:1.

[0084] The preparation method of the promoter is as follows:

[0085] (1) Add 80 g of EPEG to 300 g of water and continuously stir until completely dissolved as the base material; form material A from 3 g of acrylic acid, 30 g of N,N-dimethylacrylamide, and 60 g of deionized water, and form material B from 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; add 1.6 g of hydrogen peroxide to the base material, continue stirring for 5 min, then simultaneously dropwise add material A and material B, with the reaction temperature at 35 - 40 °C, the dropping time of material A being 50 min; the dropping time of material B being 55 min. After dropping, keep warm for 3 h to obtain a dispersion:

[0086] (2) Add an appropriate amount of distilled water to the dispersion to obtain a dilution, and then simultaneously dropwise add the aqueous solution of calcium acetate and the aqueous solution of sodium silicate to the dilution. After continuously stirring for 1 h, obtain the promoter.

[0087] In step (2), the volume ratio of the dispersion to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the dilution is 1:1:5; the molar concentrations of the aqueous solution of calcium acetate and the aqueous solution of sodium silicate are both 2 mol / L.

[0088] EPEG is ethylene glycol mono vinyl polyethylene glycol ether with a molecular weight of 3000 - 4000.

[0089] A preparation method of a cement activity enhancer includes the following preparation steps:

[0090] (1) Prepare the activator: First prepare the promoter, and then mix the promoter and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator;

[0091] (2) Add water and inorganic salts by weight parts to a stirring container, keep the temperature at 50 - 60 °C, stir for 20 minutes to completely dissolve the inorganic salts, and the stirring speed is not less than 100 rpm;

[0092] (3) Sequentially add the alkanolamine component, urea, sucrose, activator, and water-reducing component to the stirring container, keep the temperature at 50 - 60 °C, stir for 30 minutes, and the stirring speed is not less than 100 rpm. After stirring is completed, filter and discharge to obtain the final product.

[0093] Example 5

[0094] A cement activity enhancer, comprising the following raw materials in parts by weight: 20 parts of an alcohol amine component, 3 parts of urea, 7 parts of sucrose, 40 parts of inorganic salt, 10 parts of an activator, 3 parts of a water reducing component, and 40 parts of water.

[0095] The alcohol amine component is diethanol monoisopropanolamine.

[0096] The inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0097] The water reducing component is a naphthalene-based water reducing agent.

[0098] The activator is obtained by mixing a promoter and sodium lauroyl glycinate in a mass ratio of 1:1.

[0099] The preparation method of the promoter is as follows:

[0100] (1) Add 80 g of EPEG to 300 g of water, and continuously stir until completely dissolved as the base material; compose material A from 3 g of acrylic acid, 30 g of N,N-dimethylacrylamide, and 60 g of deionized water, and compose material B from 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; add 1.6 g of hydrogen peroxide to the base material, continue to stir for 5 min, then simultaneously dropwise add material A and material B, with the reaction temperature being 35 - 40 °C, the dropping time of material A being 50 min; the dropping time of material B being 55 min, after dropping is complete, keep warm for 3 h to obtain a dispersion:

[0101] (2) Add an appropriate amount of distilled water to the dispersion to obtain a dilution, and then simultaneously dropwise add the aqueous solution of calcium acetate and the aqueous solution of sodium silicate to the dilution, and continuously stir for 1 h to obtain the promoter.

[0102] In step (2), the volume ratio of the dispersion to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the dilution is 1:1:5; the molar concentrations of the aqueous solution of calcium acetate and the aqueous solution of sodium silicate are both 2 mol / L.

[0103] EPEG is ethylene glycol mono vinyl polyethylene glycol ether, with a molecular weight of 3000 - 4000.

[0104] A preparation method of a cement activity enhancer, comprising the following preparation steps:

[0105] (1) Prepare the activator: First prepare the promoter, and then mix the promoter and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator;

[0106] (2) Add water and inorganic salt in parts by weight to a stirring container, keep the temperature at 50 - 60 °C, stir for 20 minutes to completely dissolve the inorganic salt, and the stirring speed is not less than 100 rpm;

[0107] (3) Add the alkanolamine component, urea, sucrose, activator, and water-reducing component into the stirring container in sequence, keep the temperature at 50 - 60 °C, stir for 20 - 30 minutes, with the stirring speed not less than 100 rpm, and filter and discharge after stirring to obtain the final product.

[0108] Comparative Example 1

[0109] A cement activity enhancer, comprising the following raw materials in parts by weight: 20 parts of alkanolamine component, 3 parts of urea, 7 parts of sucrose, 40 parts of inorganic salt, 10 parts of activator, 3 parts of water-reducing component, and 40 parts of water.

[0110] The alkanolamine component is diethanol monoisopropanolamine.

[0111] The inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0112] The water-reducing component is a naphthalene-based water reducer.

[0113] The activator is sodium lauroyl glycinate.

[0114] In this comparative example, except for only using sodium lauroyl glycinate in the activator, the other raw materials and preparation methods are the same as those in Example 5.

[0115] Comparative Example 2

[0116] A cement activity enhancer, comprising the following raw materials in parts by weight: 20 parts of alkanolamine component, 3 parts of urea, 7 parts of sucrose, 40 parts of inorganic salt, 10 parts of activator, 3 parts of water-reducing component, and 40 parts of water.

[0117] The alkanolamine component is diethanol monoisopropanolamine.

[0118] The inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0119] The water-reducing component is a naphthalene-based water reducer.

[0120] The activator is an accelerator.

[0121] The preparation method of the accelerator is the same as that in Example 5.

[0122] In this comparative example, except for only using the accelerator in the activator, the other raw materials and preparation methods are the same as those in Example 5.

[0123] Comparative Example 3

[0124] A cement activity enhancer, comprising the following raw materials in parts by weight: 20 parts of alkanolamine component, 3 parts of urea, 7 parts of sucrose, 40 parts of inorganic salt, 10 parts of activator, 3 parts of water-reducing component, and 40 parts of water.

[0125] The alkanolamine component is diethanol monoisopropanolamine.

[0126] The inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0127] The water-reducing component is a naphthalene-based water reducer.

[0128] The activator is obtained by mixing an accelerator and sodium lauroyl glycinate in a mass ratio of 2:1.

[0129] In this comparative example, except for changing the ratio of the accelerator and sodium lauroyl glycinate in the activator, the other raw materials and preparation methods are the same as those in Example 5.

[0130] Comparative Example 4

[0131] A cement activity enhancer, comprising the following raw materials in parts by weight: 20 parts of alkanolamine component, 3 parts of urea, 7 parts of sucrose, 40 parts of inorganic salt, 10 parts of activator, 3 parts of water-reducing component, and 40 parts of water.

[0132] The alkanolamine component is diethanol monoisopropanolamine.

[0133] The inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:1.

[0134] The water-reducing component is a naphthalene-based water reducer.

[0135] The activator is obtained by mixing an accelerator and sodium lauroyl glycinate in a mass ratio of 1:2.

[0136] In this comparative example, except for changing the ratio of the accelerator and sodium lauroyl glycinate in the activator, the other raw materials and preparation methods are the same as those in Example 5.

[0137] Performance test

[0138] To verify the actual use effect of the cement enhancer of the present invention, Examples 1-5 and Comparative Examples 1-4 above were respectively added to cement materials for a full set of physical tests, and their various performances were statistically analyzed and compared according to GB175 and GB50119. The results are shown in Table 1.

[0139] In this test, "Lianshi" brand P·O 42.5R cement and Class II fly ash were used.

[0140] Analysis of hydration products: The microstructure of the specimen was observed using a cold field emission scanning electron microscope (Hitachi SU8010). After the specimen reached the age, it was cut into small pieces and dried. Gold spraying treatment was required before testing.

[0141] Analysis of pore structure: After the specimen reached the corresponding age, it was broken into 3-mm cube small pieces and dried at 80°C for 24 h. The pore diameter was measured using a mercury intrusion porosimeter.

[0142] Table 1 Experimental Results

[0143]

[0144]

[0145] From the data in the table, we can also see that compared with the blank control, the early strength at 3d and the strength at 28d of Example 3 of the present invention have been effectively improved. This is due to the addition of the enhancer of the present invention, which accelerates the cement hydration reaction, promotes the formation of hydration products. The hydration products can effectively consume calcium ions in the cement paste, etc., and accelerate the dissolution of mineral phases, reducing the porosity of the system, thereby improving its early compressive strength. From the porosity distribution of the samples Figure 1 and the microscopic morphology Figure 2 it can also be seen that the sample obtained in Example 5 of the present invention has small particle size and is relatively dense as a whole. While in Comparative Examples 1-4, the degree of hydration is relatively low and the material as a whole is not dense enough, thus resulting in a decrease in strength performance.

[0146] It should be noted that the above embodiments are only some of the embodiments of the preferred ways to implement the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

Claims

1. A cement activity enhancer, characterized in that, It comprises the following raw materials in parts by weight: 10 - 20 parts of an alkanolamine component, 3 - 5 parts of urea, 1 - 3 parts of sucrose, 35 - 50 parts of an inorganic salt, 5 - 10 parts of an activator, 3 - 7 parts of a water-reducing component, and 40 - 50 parts of water; the activator is obtained by mixing a promoter and sodium lauroyl glycinate in a mass ratio of 1:1; the preparation method of the promoter is as follows: (1) Add 80 g of EPEG to 300 g of water and continuously stir until completely dissolved as the base material; compose material A from 3 g of acrylic acid, 30 g of N,N-dimethylacrylamide, and 60 g of deionized water, and compose material B from 0.15 g of mercaptopropionic acid, 0.3 g of VC, and 50 g of deionized water; add 1.6 g of hydrogen peroxide to the base material, continue stirring for 5 min, then simultaneously dropwise add material A and material B, with the reaction temperature being 35 - 40 °C, the dropping time of material A being 50 min; the dropping time of material B being 55 min, and after dropping is completed, keep warm for 3 h to obtain a dispersion: (2) Add an appropriate amount of distilled water to the dispersion to obtain a dilution, and then simultaneously dropwise add an aqueous solution of calcium acetate and an aqueous solution of sodium silicate to the dilution, and continuously stir for 1 h to obtain the promoter.

2. The cement activity enhancer according to claim 1, characterized in that, The alkanolamine component is one or more of triethanolamine, triisopropanolamine, and diethanol monoisopropanolamine.

3. The cement activity enhancer according to claim 2, characterized in that, The alkanolamine component is diethanol monoisopropanolamine.

4. The cement activity enhancer according to claim 1, characterized in that, The inorganic salt is obtained by mixing calcium nitrate, sodium sulfate, and potassium alum in a mass ratio of 1:1:

1.

5. The cement activity enhancer according to claim 1, wherein, The water-reducing component is one of a naphthalene-based water reducer or an aliphatic water reducer.

6. The cement activity enhancer according to claim 1, characterized in that In step (2), the volume ratio of the dispersion to distilled water is 1:10; the volume ratio of the aqueous solution of calcium acetate, the aqueous solution of sodium silicate, and the dilution is 1:1:5; the molar concentrations of the aqueous solution of calcium acetate and the aqueous solution of sodium silicate are both 2 mol / L.

7. A preparation method of the cement activity enhancer according to any one of claims 1-6, characterized in that, It comprises the following preparation steps: (1) Prepare the activator: First prepare the promoter, and then mix the promoter and sodium lauroyl glycinate in a mass ratio of 1:1 to obtain the activator; (2) Add water and the inorganic salt in parts by weight to a stirring container, keep the temperature at 50 - 60 °C, and stir for 10 - 20 minutes to completely dissolve the inorganic salt, with the stirring speed not being lower than 100 rpm; (3) Sequentially add the alkanolamine component, urea, sucrose, activator, and water-reducing component to the stirring container, keep the temperature at 50 - 60 °C, and stir for 20 - 30 minutes, with the stirring speed not being lower than 100 rpm, and after stirring is completed, filter and discharge to obtain the final product.

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