Enhanced cement grinding aid and preparation method thereof

Abstract

The invention discloses an enhanced cement grinding aid and a preparation method thereof, and belongs to the technical field of cement admixtures. The concrete additive is prepared from the following raw materials in parts by weight: 20-30 parts of an alcohol amine compound, 10-20 parts of ethylene glycol, 1-3 parts of a surfactant, 0.3-0.5 part of a defoaming agent, 3-5 parts of a macromolecular synergist, 1-3 parts of a polycarboxylate superplasticizer, 0.5-1.5 parts of molasses and 20-30 parts of water. The alcohol amine compound comprises triethanolamine and modified alcohol amine; the macromolecular synergist is a sodium alginate-beta-cyclodextrin macromolecular compound. According to the cement grinding aid, the cement grinding efficiency can be remarkably improved, and the machine-hour yield is improved by 24.5% or above; the 3-day strength of the cement is improved by 5.9 MPa or above, and the 28-day strength of the cement is improved by 10.7 MPa or above, so that the cement has a good market application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of cement admixtures, and particularly relates to an enhanced cement grinding aid and a preparation method thereof. Background Art

[0002] In the cement industry, the energy consumption of the grinding process is very high. Every ton of cement produced requires grinding of about 3 tons of various materials, and the power consumption of the grinding process accounts for about 60% to 70% of the total power consumption of cement production. In order to reduce energy consumption and improve grinding efficiency, adding a small amount of grinding aids during the grinding process to improve grinding efficiency is one of the effective methods. Cement grinding aids are additives added during the cement grinding process to improve cement grinding and increase production efficiency without damaging the properties of cement. The use of cement grinding aids can significantly improve the dispersion of cement during grinding, which can not only increase unit production and reduce power consumption, but also improve cement performance and reduce the amount of clinker, which has obvious economic benefits.

[0003] Existing cement grinding aids are mainly composed of traditional organic compounds such as ethanolamines and alcohols and inorganic salts. Alcoholamines are relatively expensive and sensitive to dosage. Excessive dosage of ethanolamines will have an adverse effect on cement grinding. For example, the cement flow rate is too fast, resulting in a short residence time in the mill, and insufficient grinding causes cement to run coarse, which in turn affects the output and strength of cement. The main function of alcohols is to improve the efficiency of cement grinding, and the effect on the strength stimulation is relatively small. Inorganic salts will increase the alkali content in cement and affect the durability of concrete. In addition, some existing grinding aid products have poor stability and unreasonable mix design, which makes them unable to meet actual engineering needs, such as the effect of improving cement strength is not significant enough.

[0004] Therefore, it is urgent to research and design an enhanced cement grinding aid with good product stability, significant grinding aid effect and the ability to significantly improve cement strength. Summary of the invention

[0005] The object of the present invention is to provide an enhanced cement grinding aid, which has a small dosage, wide applicability, significantly improves the hourly output of cement mills, improves production efficiency, and can also increase the 3-day strength of cement by more than 5.9 MPa and the 28-day strength by more than 10.7 MPa.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is: An enhanced cement grinding aid is prepared from the following raw materials in parts by weight: 20-30 parts of an alcohol amine compound, 10-20 parts of ethylene glycol, 1-3 parts of a surfactant, 0.3-0.5 parts of a defoamer, 3-5 parts of a macromolecular synergist, 1-3 parts of a polycarboxylic acid water reducer, 0.5-1.5 parts of molasses, and 20-30 parts of water; the alcohol amine compound comprises triethanolamine and a modified alcohol amine; and the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular compound.

[0007] Preferably, the mass ratio of triethanolamine to modified alcoholamine in the alcoholamine complex is 1:3.

[0008] Preferably, the modified alcohol amine is prepared by the following method: adding diethanol monoisopropanolamine into a reaction container, adding an appropriate amount of 0.1M KOH solution under magnetic stirring, and then adding sunflower oil thereto, heating to 130° C., maintaining the reaction for 4-6 hours, and cooling to 45° C. after the reaction is completed to obtain the modified alcohol amine.

[0009] Preferably, the molar ratio of diethanol monoisopropanolamine to sunflower oil is 3:1.

[0010] Preferably, the amount of the KOH solution is 1% by mass of the sunflower oil.

[0011] Preferably, the macromolecular enhancer is prepared by the following method: sodium alginate, phytic acid, and β-cyclodextrin are added to deionized water respectively, stirred evenly, and then an appropriate amount of KH2PO4 is added, heated to 100°C and stirred for reaction for 1 h, and then the mixed solution is placed in a constant temperature box at 150°C for reaction for 10 hours. After the reaction, the obtained product is placed in 200 mL 0.1mol / L NaOH solution, stirred at room temperature for 2 h, filtered and then repeated the above operation, and finally the product is washed with deionized water until the pH value of the filtrate is neutral, and the product is placed in a vacuum drying oven at 55°C for 12 hours to obtain a sodium alginate-β-cyclodextrin macromolecular complex.

[0012] Preferably, the usage ratio of sodium alginate, phytic acid, β-cyclodextrin, deionized water and KH2PO4 is 1g:4g:8g:100ml:0.6g.

[0013] Preferably, the surfactant is carboxymethyl cellulose or sodium lignin sulfonate.

[0014] Preferably, the defoaming agent is fatty alcohol polyoxyethylene ether sulfate or sodium stearate.

[0015] The present invention also provides a method for preparing the above-mentioned enhanced cement grinding aid, which comprises the following steps: A: Prepare modified alcohol amine, and then compound it with triethanolamine in proportion to obtain an alcohol amine complex; B: Preparation of macromolecular synergists; C: First, place water in a stirring device, add the alcoholamine complex, stir and heat to 45°C, then add the macromolecular enhancer, and continue stirring for 20-30 minutes; D: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

[0016] The raw materials used in the present invention are all commercially available.

[0017] The designed dosage of the grinding aid of the present invention is 0.03-0.06%.

[0018] The macromolecular synergist added in the present invention is a macromolecular complex prepared by compounding sodium alginate, phytic acid and beta-cyclodextrin, wherein the carboxyl group on the surface of sodium alginate undergoes an esterification reaction with the hydroxyl group on the surface of beta-cyclodextrin, and the phosphoric acid contained in the phytic acid dehydrates and condenses with the hydroxyl groups on the surfaces of beta-cyclodextrin and sodium alginate to form a macromolecular complex. The macromolecular synergist contains multiple functional groups such as carboxyl, hydroxyl, and phosphate, and has a good adsorption effect on the surface of cement particles. The functional groups are adsorbed on the surface of cement particles to form a lubricating layer, which reduces the friction and cohesion between the particles, which helps to disperse the cement particles in the mill. The dispersed cement particles are more susceptible to the impact and grinding of the grinding media in the mill, thereby improving the grinding efficiency. At the same time, the macromolecular synergist of the present invention also contains a phosphate group, which can react with the Ca in cement. 2+ The reaction forms calcium phosphate particles, which can fill the tiny pores in cement, and the macromolecular particles in the tiny pores will continuously deposit and wrap the hydration products and the surface of the unhydrated cement particles. The macromolecular complex and the cement hydration products form a mutually interlaced spatial network structure, thereby improving the density and strength of the cement. At the same time, the hydroxyl groups and other groups contained in the enhancer can chelate the metal ions on the surface of the cementitious material, making its surface more soluble, the early hydration speed faster, and improving the early strength of the cement mortar.

[0019] The invention adopts an alcohol amine compound prepared by compounding triethanolamine and modified alcohol amine in proportion as a main grinding aid material, adopts modified alcohol amine to replace part of triethanolamine, and reduces the adverse effect on the cement grinding agent hydration process caused by excessive use of triethanolamine. The modified alcohol amine adopted is an alkanolamide product having active groups such as amide groups and hydroxyl groups obtained by amidation reaction of sunflower seed oil and diethanol monoisopropanolamine under suitable conditions. Since the amide molecule has a significant promoting effect on the hydration reaction of cement, it can prevent the problems of cracking and leakage caused by cement drying too fast, and can reduce the generation of pores in cement, further improving the density and strength of cement.

[0020] The beneficial effects of the present invention are: 1) The present invention uses modified alcohol amine and triethylamine in combination, which reduces the amount of triethanolamine, avoids the adverse effects of excessive alcohol amine substances on cement, and can also enhance the grinding aid effect; 2) Sodium alginate, phytic acid and β-cyclodextrin used in the macromolecular synergist prepared by the present invention are all natural macromolecular compounds, which are biodegradable and non-toxic, which makes the application of the synergist in cement grinding aids more environmentally friendly and safe, and makes the prepared cement grinding aids suitable for different types of cement and mills, and has wide applicability; 3) The prepared alcohol amine complex and the macromolecular enhancer have obvious synergistic effect. The combined use of the two improves the cement grinding efficiency, can promote both the early hydration of cement and the later hydration, and improves the 3-day and 28-day strength of cement, and has good market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The effects of different amounts of grinding aids on the 3d and 28d compressive strength of cement are shown in the figure. Figure 2 The following are scanning electron micrographs of cement mortars prepared in different treatment groups of the present invention, wherein a is cement mortar of the blank control group, b is cement mortar of comparative example 1, c is cement mortar of comparative example 2, and d is cement mortar of embodiment 3. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below in conjunction with specific embodiments, but is not limited thereto.

[0023] Example 1 An enhanced cement grinding aid is prepared from the following raw materials in parts by weight: 20 kg of an alcohol amine compound, 10 kg of ethylene glycol, 1 kg of carboxymethyl cellulose, 0.3 kg of sodium polyoxyethylene fatty alcohol ether sulfate, 3 kg of a macromolecular synergist, 1 kg of a polycarboxylic acid water reducer, 0.5 kg of molasses, and 20 kg of water; the alcohol amine compound is composed of triethanolamine and modified alcohol amine in a mass ratio of 1:3; and the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular compound.

[0024] The preparation method of the above-mentioned enhanced cement grinding aid comprises the following steps: A: Preparation of modified alcohol amine: Add diethanol monoisopropanolamine into a reaction vessel, add 0.1M KOH solution of 1% by mass of sunflower oil under magnetic stirring, then add sunflower oil, heat to 130°C, keep reacting for 4-6 hours, cool to 45°C after the reaction to obtain modified alcohol amine; wherein the molar ratio of diethanol monoisopropanolamine to sunflower oil is 3:1; the obtained modified alcohol amine and triethanolamine are combined into an alcohol amine complex in a mass ratio of 3:1; B: Preparation of macromolecular enhancer: 1g sodium alginate, 4g phytic acid, and 8g β-cyclodextrin were added to 100ml deionized water respectively, stirred evenly, and then 0.6g KH2PO4 was added, heated to 100℃ and stirred for 1 h, and then the mixed solution was placed in a constant temperature box at 150℃ for 10 hours. After the reaction, the obtained product was placed in 200mL 0.1 mol / LNaOH solution, stirred at room temperature for 2 hours, filtered and repeated the above operation, and finally washed with deionized water until the pH value of the filtrate was neutral, and the product was placed in a vacuum drying oven at 55℃ for 12 hours to obtain a sodium alginate-β-cyclodextrin macromolecular complex; C: Place the water in the formula in a stirring device, add the alcoholamine complex first, stir and heat to 45°C, then add the macromolecular enhancer, and continue stirring for 20-30 minutes; D: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

[0025] Example 2 An enhanced cement grinding aid is prepared from the following raw materials in parts by weight: 30 kg of an alcoholamine compound, 20 kg of ethylene glycol, 3 kg of sodium lignin sulfonate, 0.5 kg of sodium stearate, 5 kg of a macromolecular synergist, 3 kg of a polycarboxylic acid water reducer, 1.5 kg of molasses, and 30 kg of water; the alcoholamine compound is composed of triethanolamine and modified alcoholamine in a mass ratio of 1:3; and the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular compound.

[0026] The preparation method of the above-mentioned enhanced cement grinding aid comprises the following steps: A: Preparation of modified alcohol amine: Add diethanol monoisopropanolamine into a reaction vessel, add 0.1M KOH solution of 1% by mass of sunflower oil under magnetic stirring, then add sunflower oil, heat to 130°C, keep reacting for 4-6 hours, cool to 45°C after the reaction to obtain modified alcohol amine; wherein the molar ratio of diethanol monoisopropanolamine to sunflower oil is 3:1; the obtained modified alcohol amine and triethanolamine are combined into an alcohol amine complex in a mass ratio of 3:1; B: Preparation of macromolecular enhancer: 1g sodium alginate, 4g phytic acid, and 8g β-cyclodextrin were added to 100ml deionized water respectively, stirred evenly, and then 0.6g KH2PO4 was added, heated to 100℃ and stirred for 1 h, and then the mixed solution was placed in a constant temperature box at 150℃ for 10 hours. After the reaction, the obtained product was placed in 200mL 0.1 mol / LNaOH solution, stirred at room temperature for 2 hours, filtered and repeated the above operation, and finally washed with deionized water until the pH value of the filtrate was neutral, and the product was placed in a vacuum drying oven at 55℃ for 12 hours to obtain a sodium alginate-β-cyclodextrin macromolecular complex; C: Place the water in the formula in a stirring device, add the alcoholamine complex first, stir and heat to 45°C, then add the macromolecular enhancer, and continue stirring for 20-30 minutes; D: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

[0027] Example 3 An enhanced cement grinding aid is prepared from the following raw materials in parts by weight: 25 kg of an alcohol amine compound, 15 kg of ethylene glycol, 2 kg of sodium lignin sulfonate, 0.4 kg of sodium fatty alcohol polyoxyethylene ether sulfate, 4 kg of a macromolecular synergist, 2 kg of a polycarboxylic acid water reducer, 1 kg of molasses, and 25 kg of water; the alcohol amine compound is composed of triethanolamine and modified alcohol amine in a mass ratio of 1:3; and the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular compound.

[0028] The preparation method of the above-mentioned enhanced cement grinding aid comprises the following steps: A: Preparation of modified alcohol amine: Add diethanol monoisopropanolamine into a reaction vessel, add 0.1M KOH solution of 1% by mass of sunflower oil under magnetic stirring, then add sunflower oil, heat to 130°C, keep reacting for 4-6 hours, cool to 45°C after the reaction to obtain modified alcohol amine; wherein the molar ratio of diethanol monoisopropanolamine to sunflower oil is 3:1; the obtained modified alcohol amine and triethanolamine are combined into an alcohol amine complex in a mass ratio of 3:1; B: Preparation of macromolecular enhancer: 1g sodium alginate, 4g phytic acid, and 8g β-cyclodextrin were added to 100ml deionized water respectively, stirred evenly, and then 0.6g KH2PO4 was added, heated to 100℃ and stirred for 1 h, and then the mixed solution was placed in a constant temperature box at 150℃ for 10 hours. After the reaction, the obtained product was placed in 200mL 0.1 mol / LNaOH solution, stirred at room temperature for 2 hours, filtered and repeated the above operation, and finally washed with deionized water until the pH value of the filtrate was neutral, and the product was placed in a vacuum drying oven at 55℃ for 12 hours to obtain a sodium alginate-β-cyclodextrin macromolecular complex; C: Place the water in the formula in a stirring device, add the alcoholamine complex first, stir and heat to 45°C, then add the macromolecular enhancer, and continue stirring for 20-30 minutes; D: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

[0029] Comparative Example 1 An enhanced cement grinding aid is prepared from the following raw materials in parts by weight: 25 kg of an alcohol amine compound, 15 kg of ethylene glycol, 2 kg of sodium lignin sulfonate, 0.4 kg of sodium fatty alcohol polyoxyethylene ether sulfate, 2 kg of a polycarboxylic acid water reducer, 1 kg of molasses, and 25 kg of water; the alcohol amine compound is composed of triethanolamine and modified alcohol amine in a mass ratio of 1:3; and the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular compound.

[0030] The preparation method of the above-mentioned enhanced cement grinding aid comprises the following steps: A: Preparation of modified alcohol amine: Add diethanol monoisopropanolamine into a reaction vessel, add 0.1M KOH solution of 1% by mass of sunflower oil under magnetic stirring, then add sunflower oil, heat to 130°C, keep reacting for 4-6 hours, cool to 45°C after the reaction to obtain modified alcohol amine; wherein the molar ratio of diethanol monoisopropanolamine to sunflower oil is 3:1; the obtained modified alcohol amine and triethanolamine are combined into an alcohol amine complex in a mass ratio of 3:1; B: Place the water in the formula in a stirring device, add the alcoholamine complex first, stir and heat to 45°C, and continue stirring for 20-30 minutes; C: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

[0031] This comparative example is basically the same as Example 3, except that it does not contain the macromolecular synergist and the preparation method thereof.

[0032] Comparative Example 2 An enhanced cement grinding aid is prepared from the following raw materials in parts by weight: 25 kg of an alcohol amine compound, 15 kg of ethylene glycol, 2 kg of sodium lignin sulfonate, 0.4 kg of sodium fatty alcohol polyoxyethylene ether sulfate, 4 kg of a macromolecular synergist, 2 kg of a polycarboxylic acid water reducer, 1 kg of molasses, and 25 kg of water; the alcohol amine compound is composed of triethanolamine and diethanol monoisopropanolamine in a mass ratio of 1:3; and the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular compound.

[0033] The preparation method of the above-mentioned enhanced cement grinding aid comprises the following steps: A: Diethanol monoisopropanolamine and triethanolamine are mixed in a mass ratio of 3:1 to form an alcohol amine complex; B: Preparation of macromolecular enhancer: 1g sodium alginate, 4g phytic acid, and 8g β-cyclodextrin were added to 100ml deionized water respectively, stirred evenly, and then 0.6g KH2PO4 was added, heated to 100℃ and stirred for 1 h, and then the mixed solution was placed in a constant temperature box at 150℃ for 10 hours. After the reaction, the obtained product was placed in 200mL 0.1 mol / LNaOH solution, stirred at room temperature for 2 hours, filtered and repeated the above operation, and finally washed with deionized water until the pH value of the filtrate was neutral, and the product was placed in a vacuum drying oven at 55℃ for 12 hours to obtain a sodium alginate-β-cyclodextrin macromolecular complex; C: Place the water in the formula in a stirring device, add the alcoholamine complex first, stir and heat to 45°C, then add the macromolecular enhancer, and continue stirring for 20-30 minutes; D: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

[0034] This comparative example is basically the same as Example 3, except that it does not contain modified alcohol amine, and the alcohol amine compound is composed of triethanolamine and diethanol monoisopropanolamine in a mass ratio of 1:3.

[0035] Grinding aid effect verification test The materials to be ground were ground together with the cement grinding aids of Examples 1-3 and Comparative Examples 1-2 in a Φ5370mm vertical mill for 30 minutes to obtain cement, and then various physical property tests were performed on the ground cement. The grinding aid dosage was 0.05% of the total weight of the materials to be ground. A blank comparative example (without adding any grinding aid) and a commercially available grinding aid (commercially available triethanolamine) were set as controls. The material composition was 84% ​​clinker, 5% limestone, 6% phosphorus slag, and 5% dihydrate gypsum.

[0036] Test method: The particle size distribution of cement was measured using a BT-9300 laser particle size analyzer; the results are shown in Table 1.

[0037] The specific surface area was tested by the Blaine method; the cement 45μm sieve residue was tested according to GB / T 1345-2005 "Cement fineness test method sieve analysis method"; The cement obtained by grinding with cement grinding aids was mixed with water, with a water-cement ratio of 0.4. The cement mixture was poured into a mold and cured for 3 days and 28 days, and its compressive strength was tested according to the method specified in GB / T17671-1999 "Test Method for Strength of Cement Mortar". The surface morphology of cement mortar was observed with a scanning electron microscope. The results are shown in Table 2 and Figure 2 .

[0038] Table 1 Test results of cement particle size distribution in different treatment groups It can be seen from the results in Table 1 that, compared with the blank control, the particle size distribution of the cement grinding aid prepared in the embodiment of the present invention <30 μm is significantly larger than that of Comparative Examples 1 and 2, the blank control and the commercially available control. This is mainly because the macromolecular synergist used in the present invention contains multiple functional groups such as carboxyl, hydroxyl, and phosphate groups at the same time, and has a good adsorption effect on the surface of cement particles. The functional groups are adsorbed on the surface of cement particles to form a lubricating layer, which reduces the friction and cohesion between the particles, so that the cement particles have good dispersibility in the mill. The dispersed cement particles are more susceptible to the impact and grinding of the grinding media in the mill, so that the grinding is finer. The cement particles with smaller particle size have higher activity and can fully react with water to generate more hydration products, thereby improving the strength and durability of the concrete.

[0039] Table 2 Test results From the results in Table 2 above, it can be seen that the grinding efficiency of the mill is significantly improved after the cement grinding aid prepared in Examples 1-3 of the present invention is used. Compared with the blank control group, the hourly output is increased by 24.5%; compared with the blank control group, the specific surface area of ​​cement particles can be significantly increased and the 45μm sieve residue can be reduced after adding the grinding aid prepared in the present invention to the cement clinker, which shows that the components of the present invention work synergistically and have a good grinding aid effect. At the same time, compared with the blank control, the 3-day strength of cement is increased by more than 5.9MPa, and the 28-day strength is increased by more than 10.7MPa. At the same time, from Figure 2 It can also be seen that the macromolecular synergist of the present invention and the Ca 2+ The reaction forms calcium phosphate particles, which fill the tiny pores in the cement. The macromolecular particles in the tiny pores will continue to deposit and wrap the hydration products and the surface of the unhydrated cement particles. The macromolecular particles and the cement hydration products form an interlaced spatial network structure, thereby further improving the density and strength of the cement.

[0040] The present invention also studies the effect of different amounts of grinding aid on the 3-day and 28-day compressive strength of cement. Taking the grinding aid of Example 2 as an example, the effect of the amount between 0-0.1% on the strength of cement is studied. The specific results are as follows: Figure 1 As shown. Figure 1 It can be seen that the 3-day compressive strength and the 28-day compressive strength increase with the increase of the dosage, but when the dosage exceeds 0.06%, both the 3-day compressive strength and the 28-day compressive strength begin to decline, which shows that the most suitable addition amount of the grinding aid of the present invention is 0.03-0.06wt%. The continued increase in the dosage will not continuously improve the distribution of cement particles. When the dosage is too large, its grinding aid effect will be weakened. Too many grinding aid molecules are dispersed in the cement paste, which will also hinder the hydration of cement and reduce the strength of cement.

[0041] It should be noted that the above embodiments are only partial embodiments of the preferred methods of implementing the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

Claims

1. An enhanced cement grinding aid, characterized in that: The invention is prepared from the following raw materials in parts by weight: 20-30 parts of alcoholamine complex, 10-20 parts of ethylene glycol, 1-3 parts of surfactant, 0.3-0.5 parts of defoamer, 3-5 parts of macromolecular synergist, 1-3 parts of polycarboxylic acid water reducer, 0.5-1.5 parts of molasses and 20-30 parts of water; the alcoholamine complex comprises triethanolamine and modified alcoholamine; the macromolecular synergist is a sodium alginate-β-cyclodextrin macromolecular complex.

2. The enhanced cement grinding aid according to claim 1, characterized in that: The mass ratio of triethanolamine to modified alcoholamine in the alcoholamine complex is 1:

3.

3. The enhanced cement grinding aid according to claim 1, characterized in that: The modified alcohol amine is prepared by the following method: adding diethanol monoisopropanolamine into a reaction container, adding a proper amount of 0.1M KOH solution under magnetic stirring, and then adding sunflower oil thereto, heating to 130° C., maintaining the reaction for 4-6 hours, and cooling to 45° C. after the reaction is completed to obtain the modified alcohol amine.

4. The enhanced cement grinding aid according to claim 3, characterized in that: The molar ratio of diethanol monoisopropanolamine to sunflower oil is 3:

1.

5. The enhanced cement grinding aid according to claim 3, characterized in that: The amount of KOH solution used is 1% of the mass of sunflower oil.

6. The enhanced cement grinding aid according to claim 1, characterized in that: The macromolecular enhancer is prepared by the following method: sodium alginate, phytic acid and β-cyclodextrin are added to deionized water respectively, stirred evenly, and then an appropriate amount of KH2PO4 is added, heated to 100°C and stirred for reaction for 1 hour, and then the mixed solution is placed in a constant temperature box at 150°C for reaction for 10 hours. After the reaction, the obtained product is placed in 200 mL 0.1 mol / L NaOH solution, stirred at room temperature for 2 hours, filtered and then repeated once, and finally the product is washed with deionized water until the pH value of the filtrate is neutral, and the product is placed in a vacuum drying oven at 55°C for 12 hours to obtain a sodium alginate-β-cyclodextrin macromolecular complex.

7. The enhanced cement grinding aid according to claim 6, characterized in that: The dosage ratio of the sodium alginate, phytic acid, beta-cyclodextrin, deionized water and KH2PO4 is 1g:4g:8g:100ml:0.6g.

8. The enhanced cement grinding aid according to claim 1, characterized in that: The surfactant is carboxymethyl cellulose or sodium lignin sulfonate.

9. The enhanced cement grinding aid according to claim 1, characterized in that: The defoaming agent is fatty alcohol polyoxyethylene ether sulfate or sodium stearate.

10. A method for preparing the enhanced cement grinding aid according to any one of claims 1 to 7, characterized in that: It includes the following steps: A: Prepare modified alcohol amine, and then compound it with triethanolamine in proportion to obtain an alcohol amine complex; B: Preparation of macromolecular synergists; C: First, place water in a stirring device, add the alcohol amine complex, stir and heat to 45°C, then add the macromolecular enhancer, and continue stirring for 20-30 minutes; D: Raise the system temperature to 50-55°C, then add ethylene glycol, surfactant, defoamer, polycarboxylic acid water reducer and molasses in sequence, continue stirring evenly, and then return to room temperature to obtain the final product, enhanced cement grinding aid.

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