Special grinding aid for slag and its preparation method

Abstract

The application discloses a special grinding aid for slag and a preparation method thereof, and the grinding aid comprises a modified crystal nucleus early strength agent, a polymeric polyol, a styrene-maleic anhydride copolymer and water; the modified crystal nucleus early strength agent comprises a calcium-silicon reaction stock solution and a reaction bottom solution, the reaction bottom solution is compounded by propylene glycol polyether polyol and a polycarboxylic acid water reducing agent, and the propylene glycol polyether polyol comprises propylene glycol, an epoxide compound, a solvent and sodium methoxide; during preparation, the modified crystal nucleus early strength agent, the polymeric polyol, the styrene-maleic anhydride copolymer and water are mixed and then are mixed by high-speed stirring to obtain the grinding aid. The grinding aid has good dispersion stability, can effectively prevent the agglomeration and adhesion of slag powder, and improves the grinding efficiency of slag particles; and the grinding aid can react with the components in the slag during the grinding process, excites the potential activity of the slag, and improves the strength of each age period.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of grinding aids, and particularly relates to a grinding aid special for slag and a preparation method thereof. BACKGROUND

[0002] Slag is an industrial waste residue produced in pig iron smelting, and has high potential activity, so that ground slag powder is widely used in preparation of high-performance concrete. However, the slag has the defects of poor grindability and low early activity in the use process. Although the performance of the slag can be improved by prolonging the grinding time, the energy consumption is increased, and the grinding efficiency is reduced. Meanwhile, with the prolonging of the grinding time of the slag, the electric valence bond in the slag is broken, and a series of staggered active points are formed on both sides of the fracture surface, which attract each other, so that the fracture surface tends to be healed and the material is aggregated, thereby greatly reducing the grinding yield and quality.

[0003] Therefore, in order to reduce the energy consumption in the grinding process and prevent the aggregation of the slag, it is a simple and easy method to use a grinding aid. However, the existing grinding aid lacks the activity excitation ability for the slag powder, and there is an urgent need for a grinding aid special for grinding the slag and effectively developing the potential activity of the slag. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a grinding aid capable of effectively exciting the potential activity of slag powder and a preparation method thereof. The grinding aid is based on the addition of a modified crystal nucleus early strength agent prepared from propylene glycol polyether polyol, can be effectively adsorbed on the surface of C-S-H crystal nucleus through coordination bond, control the size of the particle diameter, so that the prepared crystal nucleus has smaller size; and the addition of styrene-maleic anhydride copolymer as a hyperdispersant makes the dispersion of the crystal nucleus and the solvent stable, and further has excellent dispersion stability, which is helpful to the performance stability of the grinding aid.

[0005] The technical scheme of the present application is that the grinding aid special for slag includes the following raw materials in parts by weight: modified crystal nucleus early strength agent 4-9 parts, polyether polyol 5-10 parts, styrene-maleic anhydride copolymer 1-2 parts and water 4-5 parts.

[0006] The modified crystal nucleus early strength agent includes calcium-silicon reaction stock solution and reaction bottom liquid in a mass ratio of 1-4:1, wherein the reaction bottom liquid is compounded from propylene glycol polyether polyol and polycarboxylic acid water reducing agent in a mass ratio of 1.6-2:1.

[0007] The raw materials used in the propylene glycol polyether polyol include propylene glycol 2-8 parts, epoxy compound 4-20 parts, solvent 10-15 parts and sodium methoxide 0.3-0.8 parts in parts by weight.

[0008] The special grinding aid for slag in the application is prepared by introducing the modified crystal nucleus early strength agent prepared from the propylene glycol polyether polyol formed by the reaction of propylene glycol and an epoxy compound. The hydroxyl groups on the chain of the propylene glycol polyether polyol can form a coordination bond adsorption with metal ions in the C-S-H crystal nucleus, and then the propylene glycol polyether polyol can be adsorbed on the C-S-H crystal nucleus to tightly wrap the crystal nucleus surface, limit the size growth of the crystal nucleus, effectively control the size to form smaller size particle diameter, and then improve the dispersion stability of the prepared modified crystal nucleus early strength agent and the effective activity of the modified crystal nucleus early strength agent. At the same time, the addition of the modified crystal nucleus early strength agent can adsorb and soften the surface of the slag powder, make the slag more easily broken, prevent the agglomeration and adhesion of the slag powder, and improve the grinding efficiency of the slag particles. The modified crystal nucleus early strength agent can generate a relatively stable complex with calcium ions and aluminum ions in the slag powder in an alkaline condition, accelerate the migration of the ions, and the hydroxyl ions in the hydration environment can also promote the disintegration of calcium in the slag powder to generate calcium hydroxide, so that the activity of each age period is significantly improved, which is helpful to stimulate the potential activity of the slag powder.

[0009] In addition, the styrene-maleic anhydride copolymer is added in the grinding aid, which can anchor the groups on the propylene glycol polyether polyol to the surface of the solid particles, and the solvated chain fully expands in the medium to form a steric layer to prevent the flocculation and agglomeration of the solid particles, so as to achieve the effect of steric hindrance.

[0010] Further, the propylene glycol polyether polyol used in the grinding aid is prepared by the following steps: mixing and stirring propylene glycol and a solvent at 30-40℃, adding an epoxy compound and heating to 90-180℃, adding a catalyst sodium methoxide, and stirring at 0.1-2.0MPa for 4-8h to prepare the propylene glycol polyether polyol.

[0011] Further, the epoxy compound used in the grinding aid can be ethylene oxide, propylene oxide, epichlorohydrin or glycidyl ether.

[0012] Further, the calcium-silicon reaction stock solution used in the grinding aid includes calcium salt and silicate in a mass ratio of 5-8:6; wherein the calcium salt is calcium formate, calcium acetate, calcium bicarbonate, calcium nitrate or calcium hydroxide, and the silicate is sodium silicate, potassium silicate or sodium fluorosilicate.

[0013] Further, the modified crystal nucleus early strength agent used in the grinding aid is prepared by the following steps: uniformly adding the calcium-silicon reaction stock solution to the reaction bottom liquid, adjusting the pH value to 10.5-12.5, and hydrothermally reacting at 15-60℃ for 8-14h to prepare the modified crystal nucleus early strength agent.

[0014] The method for preparing the above-mentioned special grinding aid for slag comprises the following steps: mixing and stirring a modified crystal nucleus early strength agent, a polyol, a styrene-maleic anhydride copolymer and water for 0.5-1 h, wherein the rotating speed is 3000-5000 rpm

[0015] The special grinding aid for mineral powder prepared by the present application has a mixing amount of 0.1-0.5% of the mass of the mineral powder.

[0016] Advantages: compared with the prior art, the significant advantages of the present application are: first, the prepared modified crystal nucleus early strength agent has excellent dispersion stability, thereby improving the effective activity in the later application; second, the grinding aid prepared based on the modified crystal nucleus early strength agent can react with the components in the slag in the grinding process, thereby stimulating the potential activity of the slag, and as the grinding aid, the slag can be effectively prevented from agglomeration and adhesion, thereby improving the grinding efficiency of the slag particles. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Example 1 of the present application;

[0018] Figure 2 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Example 1 of the present application after standing for 14 days;

[0019] Figure 3 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Comparative Example 1 of the present application;

[0020] Figure 4 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Comparative Example 1 of the present application after standing for 14 days;

[0021] Figure 5 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Example 2 of the present application;

[0022] Figure 6 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Example 2 of the present application after standing for 14 days;

[0023] Figure 7 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Comparative Example 2 of the present application;

[0024] Figure 8 Product diagram of the modified crystal nucleus early strength agent suspension prepared in Comparative Example 2 of the present application after standing for 14 days. DETAILED DESCRIPTION

[0025] The technical solutions of the present application will be further described in detail below in combination with the drawings and examples.

[0026] It should be noted that the polymeric polyol used in the present application is produced by Nanjing Changjiang Jiangyu Energy Technology Co., Ltd. and can be directly obtained from the market; the styrene-maleic anhydride copolymer is from Wuhan Kemik Biological Medicine Technology Co., Ltd. and can also be directly obtained from the market; the polycarboxylic acid water reducing agent is produced by Jiangsu Subote New Material Co., Ltd. and can also be directly obtained from the market. The raw materials used in the present application are all known technologies and have no improvements.

[0027] Example 1

[0028] The raw material components of the grinding aid for slag in this example 1 are shown in Table 1, the component content of the modified crystal nucleus early strength agent used is shown in Table 2, and the component content of the propylene glycol polyether polyol is shown in Table 3.

[0029] Table 1 Raw material components of the grinding aid of example 1

[0030]

[0031]

[0032] Table 2 Raw material components of the modified crystal nucleus early strength agent of example 1

[0033]

[0034] Table 3 Raw material components of the propylene glycol polyether polyol of example 1

[0035] No. Raw material Content / portion 1 Propylene alcohol 5 2 Epoxymethane 12 3 Sodium methoxide 0.6 4 Water 12

[0036] The preparation method of the grinding aid of this example 1 includes the following steps:

[0037] (1) Preparation of propylene glycol polyether polyol: propylene glycol and water are mixed and stirred at 35℃, and then the temperature is raised to 130℃ by adding ethylene oxide, a catalyst sodium methoxide is added, and the reaction is stirred at 0.1-2.0 MPa for 5h, and then the monomer is removed and the temperature is lowered to obtain the propylene glycol polyether polyol.

[0038] (2) Preparation of modified crystal nucleus early strength agent: the calcium-silicon reaction stock solution and the reaction bottom liquid are mixed, the pH value is adjusted to 10.5-12.5, and then the hydrothermal reaction is carried out at 40℃ for 10h to obtain the modified crystal nucleus early strength agent.

[0039] (3) Preparation of grinding aid: the modified crystal nucleus early strength agent, polymeric polyol, styrene-maleic anhydride copolymer and water are mixed, and then the stirring reaction is carried out at 3000 rpm for 1h to obtain the grinding aid.

[0040] Comparative Example 1

[0041] The basic steps are the same as those in Example 1, except that no propylene glycol polyether polyol is added in the preparation of the modified crystal nucleus early strength agent, and the raw material components of the modified crystal nucleus early strength agent used are shown in Table 4.

[0042] Table 4 Raw material components of the modified crystal nucleus early strength agent of Comparative Example 1

[0043]

[0044]

[0045] Performance test 1: stability test of the modified crystal nucleus early strength agent

[0046] The modified crystal nucleus early strength agents prepared in Example 1 and Comparative Example 1 of the present application are subjected to dispersion stability test, and the results obtained are shown in Table 8, respectively. Figure 1 to Figure 4 It can be seen from Table 8 that the modified crystal nucleus early strength agent prepared by using the raw materials and the preparation method of Example 1 of the present application can be dispersed stably, and no stratification phenomenon occurs after 14 days; while the modified crystal nucleus early strength agent prepared by using the raw materials and the preparation method of Comparative Example 1 has obviously stratified after 14 days of storage. Figure 2 Figure 4

[0047] Example 2

[0048] The raw material components of the grinding aid for slag in this Example 2 are shown in Table 5, the component contents of the modified crystal nucleus early strength agent used are shown in Table 6, and the component contents of the propylene glycol polyether polyol are shown in Table 7.

[0049] Table 5 Raw material components of the grinding aid of Example 2

[0050] No. Raw material Content / portion 1 Modified crystal nucleus early strength agent 8 2 Polymerized polyol 6 3 Styrene-maleic anhydride copolymer 1 4 Water 5

[0051] Table 6 Raw material components of the modified crystal nucleus early strength agent of Example 2

[0052]

[0053] Table 7 Raw material components of the propylene glycol polyether polyol of Example 2

[0054]

[0055]

[0056] The preparation method of the grinding aid of this Example 2 includes the following steps:

[0057] ​​(1) Preparation of propenyl alcohol polyether polyol: propenyl alcohol and water are mixed and stirred at 38°C, and ethylene oxide is added to increase the temperature to 160°C, sodium methoxide is added as catalyst, and the reaction is stirred at 0.1-2.0 MPa for 6 h, and the monomer is removed to decrease the temperature to prepare the propenyl alcohol polyether polyol.

[0058] (2) Preparation of modified crystal nucleus early strength agent: the calcium-silicon reaction stock solution and reaction bottom solution are mixed, the pH value is adjusted to 10.5-12.5, and the hydrothermal reaction is carried out at 25°C for 13 h to prepare the modified crystal nucleus early strength agent.

[0059] (3) Preparation of grinding aid: the modified crystal nucleus early strength agent, polymeric polyol, styrene-maleic anhydride copolymer and water are mixed, and the stirring reaction is carried out at 4000 rpm for 50 min to prepare the grinding aid.

[0060] Comparative Example 2

[0061] The basic steps are the same as those in Example 2, except that no propenyl alcohol polyether polyol is added when preparing the modified crystal nucleus early strength agent, and the raw material components of the modified crystal nucleus early strength agent used are shown in Table 8.

[0062] Table 8 Raw material components of modified crystal nucleus early strength agent in Comparative Example 2

[0063]

[0064] Performance test 2: stability test of modified crystal nucleus early strength agent

[0065] The dispersion stability of the modified crystal nucleus early strength agents prepared in Example 2 and Comparative Example 2 is tested, and the results obtained are shown in Table 12. Figure 5 to Figure 8 It can be seen from Table 12 that the modified crystal nucleus early strength agent prepared by using the raw materials and preparation method in Example 2 is stable in dispersion, and no stratification phenomenon occurs after 14 days; while the modified crystal nucleus early strength agent prepared by using the raw materials and preparation method in Comparative Example 2 has obviously stratified after 14 days of storage. Figure 6 Figure 8

[0066] Example 3

[0067] The raw material components of the grinding aid for slag in this Example 3 are shown in Table 9, the component contents of the modified crystal nucleus early strength agent used are shown in Table 10, and the component contents of the propenyl alcohol polyether polyol are shown in Table 11.

[0068] Table 9 Raw material components of grinding aid in Example 3

[0069] No. Raw material Content / portion 1 Modified crystal nucleus early strength agent 6 2 Polymerized polyol 8 3 Styrene-maleic anhydride copolymer 2 4 Water 4

[0070] Table 10 Raw material components of modified crystal nucleus early strength agent in Example 3​​

[0071]

[0072] Table 11 Raw material components of propenyl alcohol polyether polyol of Example 3

[0073] No. Raw material Content / portion 1 Propylene alcohol 2 2 Epoxymethane 4 3 Sodium methoxide 0.3 4 Water 10

[0074] The preparation method of the grinding aid of this Example 4 comprises the following steps:

[0075] (1) Preparation of propenyl alcohol polyether polyol: propenyl alcohol and water are mixed and stirred at 30°C, and then ethylene oxide is added to increase the temperature to 90°C, and a catalyst, sodium methoxide, is added, and the reaction is stirred at 0.1-2.0 MPa for 8 h, and then the temperature is decreased for monomer removal to prepare the propenyl alcohol polyether polyol.

[0076] (2) Preparation of modified crystal nucleus early strength agent: the calcium-silicon reaction stock solution and the reaction bottom solution are mixed, the pH value is adjusted to 10.5-12.5, and then the hydrothermal reaction is carried out at 15°C for 14 h to prepare the modified crystal nucleus early strength agent.

[0077] (3) Preparation of grinding aid: the modified crystal nucleus early strength agent, the polymeric polyol, the styrene-maleic anhydride copolymer, and water are mixed, and then the stirring reaction is carried out at a rotation speed of 5000 rpm for 30 min to prepare the grinding aid.

[0078] Example 4

[0079] The raw material components of the grinding aid of this Example 4 are shown in Table 12 below, the component content of the modified crystal nucleus early strength agent used is shown in Table 13 below, and the component content of the propenyl alcohol polyether polyol is shown in Table 14 below.

[0080] Table 12 Raw material components of grinding aid of Example 4

[0081] No. Raw material Content / portion 1 Modified crystal nucleus early strength agent 4 2 Polymerized polyol 10 3 Styrene-maleic anhydride copolymer 2 4 Water 4

[0082] Table 13 Raw material components of modified crystal nucleus early strength agent of Example 4

[0083]

[0084] Table 14 Raw material components of propenyl alcohol polyether polyol of Example 4

[0085] No. Raw material Content / portion 1 Propylene alcohol 8 2 Glycidyl ether 20 3 Sodium methoxide 0.8 4 Water 15

[0086] The preparation method of the grinding aid of this Example 4 comprises the following steps:

[0087] (1) Preparation of allyl alcohol polyether polyol: allyl alcohol and water are mixed and stirred at 40°C, and then ethylene oxide is added to increase the temperature to 180°C, sodium methoxide is added as a catalyst, and the reaction is stirred at 0.1-2.0 MPa for 4 h, and then the monomer is removed and cooled to obtain the allyl alcohol polyether polyol.

[0088] (2) Preparation of modified crystal nucleus early strength agent: the calcium-silicon reaction stock solution and the reaction bottom solution are mixed, the pH value is adjusted to 10.5-12.5, and then the mixture is hydrothermally reacted at 60°C for 8 h to obtain the modified crystal nucleus early strength agent.

[0089] (3) Preparation of grinding aid: the modified crystal nucleus early strength agent, polymeric polyol, styrene-maleic anhydride copolymer, and water are mixed, and then the mixture is stirred at a speed of 5000 rpm for 1 h to obtain the grinding aid.

[0090] Performance test 2: grinding aid performance test

[0091] The grinding aids prepared in Examples 1-4 and Comparative Examples 1-2 are used for grinding of the mineral powder, the dosage of which is 0.3% of the mass of the mineral powder to be ground, and the modified crystal nucleus early strength agent suspension used is the one that has been standing for 14 days, and the physical properties of the obtained mineral powder, including the specific surface area, the water requirement ratio, and the activity index at 3d, 7d, and 28d, are detected. The specific surface area is determined according to GB / T 8074-2008 “Determination of Blaine Fineness of Cement”; the water requirement ratio is determined according to GB / T 18736-2017 “Mineral Admixtures for High-Performance Concrete”; and the activity index is determined according to GB / T 18046-2017 “Ground Granulated Blast-Furnace Slag for Use in Cement, Mortar, and Concrete”. The results are shown in Table 15 below.

[0092] Table 15 Properties of the mineral powder ground with the grinding aids prepared in Examples 1-4 and Comparative Examples 1-2

[0093] Test item Specific surface area (m 2 / kg) Water requirement ratio (%) 3d activity index (%) 7d activity index (%) 28d activity index (%) Comparative example 1 440 102 - 80 105 Comparative example 2 663 98 98 106 118 Example 1 659 98 96 106 116 Example 2 646 98 98 108 118 Example 3 654 99 100 112 120 Example 4 623 98 101 110 118 Comparative example 1 591 100 93 104 108 Comparative example 2 605 100 90 102 111

[0094] Among them, Comparative Example 1 is a slag powder in which the same amount of deionized water is used instead of the grinding aid, and the other grinding conditions are the same, and Comparative Example 2 is a slag powder in which the grinding aid prepared in Example 1 is used immediately for grinding (without standing), and the properties of the slag powder are detected.

[0095] In combination with examples 1-4, the application can effectively activate the activity of the mineral powder by using propenyl polyether polyol to prepare the modified crystal core early strength agent and applying it in the grinding aid after standing for 14 days. In combination with the control example 1 and example 1, after using the grinding aid, the specific surface area is significantly improved, the water requirement is reduced, and the activity index at each age is obviously improved, so it can be known that the grinding aid prepared by the application can effectively improve the performance of the mineral powder after grinding. In combination with the control example 2 and example 1, the modified crystal core early strength agent after standing for 14 days can still achieve a similar technical effect to the modified crystal core early strength agent prepared at present, so it can be known that the modified crystal core early strength agent prepared by the application has strong dispersion stability and can effectively maintain its activity.

Claims

1. A grinding aid specific to slag characterized in that, The raw materials include, by weight fraction, modified crystal core early strength agent 4-9 parts, polymeric polyol 5-10 parts, styrene-maleic anhydride copolymer 1-2 parts and water 4-5 parts; The modified crystal core early strength agent includes calcium-silicon reaction stock solution and reaction bottom liquid in a mass ratio of 1-4:1, wherein the reaction bottom liquid is compounded by propylene glycol polyether polyol and polycarboxylic acid water reducing agent in a mass ratio of 1.6-2:1; the modified crystal core early strength agent is prepared by the following steps: uniformly adding the calcium-silicon reaction stock solution into the reaction bottom liquid, adjusting the pH value to 10.5-12.5, and hydrothermally reacting at 15-60℃ for 8-14 h to obtain the modified crystal core early strength agent; The raw materials of the propylene glycol polyether polyol include, by weight fraction, propylene glycol 2-8 parts, epoxy compound 4-20 parts, solvent 10-15 parts and sodium methoxide 0.3-0.8 parts; the propylene glycol polyether polyol is prepared by the following steps: mixing and stirring the propylene glycol and the solvent at 30-40℃, adding the epoxy compound and heating to 90-180℃, adding the catalyst sodium methoxide, and stirring at 0.1-2.0 MPa for 4-8 h to obtain the propylene glycol polyether polyol.

2. The grinding aid special for slag according to claim 1, characterized in that, The epoxy compound is ethylene oxide, propylene oxide, epichlorohydrin or glycidyl ether.

3. The grinding aid special for slag according to claim 1, characterized in that, The calcium-silicon reaction stock solution includes calcium salt and silicate in a mass ratio of 5-8:6; wherein the calcium salt is calcium formate, calcium acetate, calcium bicarbonate, calcium nitrate or calcium hydroxide, and the silicate is sodium silicate, potassium silicate or sodium fluorosilicate.

4. A method of preparing the grinding aid specific to slag as claimed in claim 1, wherein, The steps include: mixing and stirring the modified crystal core early strength agent, polymeric polyol, styrene-maleic anhydride copolymer and water for 0.5-1 h; wherein the rotation speed is 3000-5000 rpm.

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