Grinding aid for producing cement clinker powder and use method of grinding aid

Abstract

The invention discloses a grinding aid for producing cement clinker powder and a use method of the grinding aid. The grinding aid comprises the following components in parts by weight: 20-27 parts of a mixture of hydrogen peroxide and polyol, 3-6 parts of tetraethoxysilane, 1.5-2.4 parts of a solid calcium source, 0.5-0.75 part of lignosulfonate and 1-2 parts of modified calcium stearate. The grinding aid is obtained by mixing the raw materials and then quickly stirring and uniformly dispersing the raw materials. Wherein the modified calcium stearate is obtained by mixing calcium stearate with an ethanol solution of a polycarboxylate superplasticizer and then grinding. The use method comprises the following steps: uniformly spraying the grinding aid on cement clinker, standing, and grinding after completion. The grinding aid disclosed by the invention not only can reduce the energy consumption at the early stage of grinding and improve the grinding efficiency, but also is beneficial to improving the early strength of the prepared cement clinker.

Description

Technical Field

[0001] The invention relates to the technical field of grinding aid preparation, and in particular to a grinding aid for producing cement clinker powder and a use method thereof. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] After the cement clinker is fired, it needs to be ground to a suitable particle size to form a certain particle gradation, increase the specific surface area, and thus increase the contact area between cement and water, making the cement hydration reaction more rapid and sufficient. The grinding of cement clinker is not only related to the performance and quality of cement, but also directly affects the mechanical properties and durability of the formed cement-based materials. However, the grinding of cement clinker requires a lot of energy consumption. Adding grinding aids to cement clinker can help improve grinding efficiency, reduce energy consumption, and thus reduce the production cost of enterprises.

[0004] Commonly used grinding aids include polyols, polyol amines, etc., which can improve grinding efficiency. This is because during the grinding process, as the cement clinker particles are gradually refined, the specific surface area increases, and the cement particle surface is charged due to bond breaking, which will cause the particles to adsorb and agglomerate with each other, which will reduce the grinding efficiency and increase energy consumption. However, since the cement clinker is obtained by solid phase reaction of each raw material under high temperature calcination before grinding, the obtained cement clinker becomes a relatively hard block. The above-mentioned grinding aids generally play the above-mentioned role after the block cement clinker has been ground to finer particles, which makes it difficult to reduce the energy consumption and grinding efficiency in the early stage of grinding. Summary of the invention

[0005] In view of the above problems, the present invention provides a grinding aid for producing cement clinker powder and a method for using the same, which can not only reduce the energy consumption in the early stage of grinding and improve the grinding efficiency, but also help to improve the early strength of the prepared cement clinker. Specifically, the technical solution of the present invention is as follows.

[0006] First, the present invention discloses a grinding aid for producing cement clinker powder, which comprises: 20-27 parts by weight of a mixture of hydrogen peroxide and polyol, 3-6 parts by weight of ethyl orthosilicate, 1.5-2.4 parts by weight of a solid calcium source, 0.5-0.75 parts by weight of lignin sulfonate, and 1-2 parts by weight of modified calcium stearate. The above raw materials are mixed and quickly stirred and dispersed uniformly to obtain the grinding aid.

[0007] Furthermore, the mass fraction of the hydrogen peroxide solution in the mixture is 20-30%.

[0008] Furthermore, the polyol includes at least one of ethylene glycol, propylene glycol, glycerol, etc. The polyol helps to reduce the surface energy of cement clinker particles, eliminate the electrostatic effect, and accelerate the fluidity of cement clinker particles, thereby improving the grinding efficiency.

[0009] Further, the solid calcium source includes at least one of calcium oxide, calcium hydroxide, carbide slag, etc. Optionally, the particle size of the solid calcium source is not less than 400 meshes.

[0010] Furthermore, the lignin sulfonate includes at least one of sodium lignin sulfonate, calcium lignin sulfonate, etc. The lignin sulfonate helps to improve the dispersion state of cement clinker particles and reduce the friction between cement clinker particles, thereby helping to improve grinding efficiency and reduce energy consumption.

[0011] Furthermore, the modified calcium stearate is obtained by mixing calcium stearate with an ethanol solution of a polycarboxylate water-reducing agent and then grinding the mixture.

[0012] Furthermore, the ratio of the calcium stearate to the ethanol solution of the polycarboxylate water-reducing agent is 1g:0.4-0.7ml.

[0013] Further, the mass fraction of the polycarboxylate water-reducing agent in the ethanol solution is 2-3.5%. The mass fraction of the ethanol solution is not less than 80%. Optionally, the particle size of the calcium stearate is not less than 400 mesh.

[0014] Secondly, the method for using the grinding aid for producing cement clinker powder of the present invention comprises the following steps: spraying the grinding aid evenly on the cement clinker and then letting it stand, and then grinding it.

[0015] Furthermore, the grinding aid is added to the cement clinker in an amount of 0.2-0.4% of its mass. Optionally, the standing time is 1-2 min.

[0016] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects: The cement clinker grinding aid of the present invention uses a mixture of hydrogen peroxide and polyol as a mother liquor, and adds functional components such as tetraethyl orthosilicate, solid calcium source and modified calcium stearate therein, which can not only reduce the energy consumption in the early stage of grinding, improve the grinding efficiency, but also help to improve the early strength of the prepared cement clinker. This is because: first, in the process of grinding after the mother liquor and tetraethyl orthosilicate are infiltrated into the cement clinker, hydrogen peroxide decomposes to produce oxygen and water under the heat generated by grinding, and the tetraethyl orthosilicate is hydrolyzed in the alkaline environment of the cement clinker after meeting water to form nano silicon dioxide and ethanol liquid. On the one hand, the mixed gas formed by the ethanol liquid and oxygen in the cement clinker expands in volume under the grinding heat and plays a cracking effect, which helps to increase the number of cracks in the cement clinker and accelerate the cracking of the cement clinker under the grinding action. On the other hand, the local high temperature generated by grinding causes the mixed gas to produce a micro-explosion effect, thereby accelerating the cracking of the cement clinker and improving the grinding efficiency. The above process effectively improves the grinding efficiency of the cement clinker in the early stage of grinding and reduces energy consumption. Secondly, the nano silicon dioxide particles formed by the hydrolysis of the tetraethyl orthosilicate have high reactivity, and the nano silicon dioxide particles and the solid calcium source can effectively improve the early strength of the cement clinker prepared by the present invention, because when the cement clinker is used to prepare cement-based materials, the nano silicon dioxide particles and the solid calcium source can be quickly hydrated under the action of mixing water to form a hydrated calcium silicate gelling component in the early hydration stage of the cement clinker, which not only increases the gelling component content in the early hardening stage of the cement-based material, but also helps to induce the hydration reaction as a nucleation center, thereby improving the early strength. Thirdly, the modified calcium stearate can effectively improve the grinding efficiency of cement clinker, and the present invention first uses the complexation of the calcium stearate and the polycarboxylate water-reducing agent to load the polycarboxylate water-reducing agent on the calcium stearate. After entering the cement clinker, the modified calcium stearate can be complexed with the calcium ions on the cement clinker particles through the carboxyl group of the polycarboxylate water-reducing agent, so that the calcium stearate is connected to the surface of the cement clinker particles for synchronous grinding, reducing the attraction between the cement clinker particles, reducing agglomeration, improving dispersibility, and thus improving the grinding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0018] Figure 1 This is a sample diagram of a mixture of hydrogen peroxide and ethylene glycol prepared in Example 1 below.

[0019] Figure 2 This is a sample diagram of modified calcium stearate powder prepared in Example 1 below. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually carried out under conventional conditions or under conditions recommended by the manufacturer.

[0021] Unless otherwise defined, all professional and scientific terms used in the present invention have the same meanings as those familiar to those skilled in the art. The reagents or raw materials used in the present invention can be purchased through conventional channels. Unless otherwise specified, the reagents or raw materials used in the present invention are used in a conventional manner in the art or in accordance with the product instructions.

[0022] In addition, any method and material similar or equivalent to the described content can be applied to the method of the present invention. The preferred implementation methods and materials described in the present invention are only for demonstration purposes. The technical solution of the present invention is now further described in conjunction with specific implementation methods.

[0023] Example 1 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) Mix hydrogen peroxide and ethylene glycol and stir evenly to form a mixture with a mass fraction of 25% hydrogen peroxide solution (such as Figure 1 as shown), for standby use.

[0024] (2) Mix the polycarboxylate water reducer with 92% ethanol solution to form a modified solution with a water reducer mass fraction of 2.5%. Then mix the 500-mesh calcium stearate powder and the modified solution at a ratio of 1g:0.6ml and stir evenly. Then grind mechanically until the ethanol solution is completely evaporated to obtain modified calcium stearate powder (such as Figure 2 as shown).

[0025] (3) Take the following raw materials: 24 parts by weight of the mixture of this example, 5 parts by weight of tetraethyl orthosilicate, 2 parts by weight of 500-mesh calcium hydroxide powder, 0.65 parts by weight of calcium lignin sulfonate, and 1.7 parts by weight of the modified calcium stearate of this example. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0026] Spray 0.35% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 30 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Cement Mortar Strength (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0027] Example 2 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) Mix hydrogen peroxide and propylene glycol and stir evenly to form a mixture with a mass fraction of 20% of hydrogen peroxide solution, and set aside.

[0028] (2) The polycarboxylate water reducer was mixed with 80% ethanol solution to form a modified solution with a water reducer mass fraction of 3.5%. Then, 600-mesh calcium stearate powder and the modified solution were mixed at a ratio of 1g:0.4ml and stirred evenly, and then mechanically ground until the ethanol solution was completely volatilized to obtain modified calcium stearate powder.

[0029] (3) Take the following raw materials: 27 parts by weight of the mixture of this example, 6 parts by weight of tetraethyl orthosilicate, 2.4 parts by weight of 600-mesh calcium oxide powder, 0.75 parts by weight of sodium lignin sulfonate, and 2 parts by weight of the modified calcium stearate of this example. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0030] Spray 0.2% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 30 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Cement Mortar Strength (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0031] Example 3 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) Mix hydrogen peroxide and ethylene glycol and stir evenly to form a mixture with a mass fraction of 30% of hydrogen peroxide solution, and set aside.

[0032] (2) The polycarboxylate water reducer was mixed with 95% ethanol solution to form a modified solution with a water reducer mass fraction of 2%. Then, 400-mesh calcium stearate powder and the modified solution were mixed at a ratio of 1 g:0.7 ml and stirred evenly, and then mechanically ground until the ethanol solution was completely volatilized to obtain modified calcium stearate powder.

[0033] (3) Take the following raw materials: 20 parts by weight of the mixture of this embodiment, 3 parts by weight of tetraethyl orthosilicate, 1.5 parts by weight of 400-mesh carbide slag powder, 0.5 parts by weight of sodium lignin sulfonate, and 1 part by weight of the modified calcium stearate of this embodiment. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0034] Spray 0.4% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 25 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0035] Example 4 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) The polycarboxylate water reducer was mixed with 92% ethanol solution to form a modified solution with a water reducer mass fraction of 2.5%. Then, 500-mesh calcium stearate powder and the modified solution were mixed at a ratio of 1g:0.6ml and stirred evenly, and then mechanically ground until the ethanol solution was completely volatilized to obtain modified calcium stearate powder.

[0036] (2) Take the following raw materials: 24 parts by weight of ethylene glycol, 5 parts by weight of tetraethyl orthosilicate, 2 parts by weight of 500-mesh calcium hydroxide powder, 0.65 parts by weight of calcium lignin sulfonate, and 1.7 parts by weight of the modified calcium stearate of this embodiment. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0037] Spray 0.35% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 30 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Cement Mortar Strength (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0038] Example 5 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) Mix hydrogen peroxide and ethylene glycol and stir evenly to form a mixture with a mass fraction of 30% of hydrogen peroxide solution, and set aside.

[0039] (2) The polycarboxylate water reducer was mixed with 95% ethanol solution to form a modified solution with a water reducer mass fraction of 2%. Then, 400-mesh calcium stearate powder and the modified solution were mixed at a ratio of 1 g:0.7 ml and stirred evenly, and then mechanically ground until the ethanol solution was completely volatilized to obtain modified calcium stearate powder.

[0040] (3) Take the following raw materials: 20 parts by weight of the mixture of this embodiment, 1.5 parts by weight of 400-mesh carbide slag powder, 0.5 parts by weight of sodium lignin sulfonate, and 1 part by weight of the modified calcium stearate of this embodiment. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0041] Spray 0.4% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 25 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0042] Example 6 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) Mix hydrogen peroxide and ethylene glycol and stir evenly to form a mixture with a mass fraction of 25% of hydrogen peroxide solution for later use.

[0043] (2) The polycarboxylate water reducer was mixed with 92% ethanol solution to form a modified solution with a water reducer mass fraction of 2.5%. Then, 500-mesh calcium stearate powder and the modified solution were mixed at a ratio of 1 g:0.6 ml and stirred evenly, and then mechanically ground until the ethanol solution was completely volatilized to obtain modified calcium stearate powder.

[0044] (3) Take the following raw materials: 24 parts by weight of the mixture of this example, 5 parts by weight of tetraethyl orthosilicate, 0.65 parts by weight of calcium lignin sulfonate, and 1.7 parts by weight of the modified calcium stearate of this example. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0045] Spray 0.35% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 30 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Cement Mortar Strength (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0046] Example 7 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: (1) Mix hydrogen peroxide and propylene glycol and stir evenly to form a mixture with a mass fraction of 20% of hydrogen peroxide solution, and set aside.

[0047] (2) Take the following raw materials: 27 parts by weight of the mixture of this example, 6 parts by weight of tetraethyl orthosilicate, 2.4 parts by weight of 600-mesh calcium oxide powder, 0.75 parts by weight of sodium lignin sulfonate, and 2 parts by weight of 600-mesh calcium stearate powder. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0048] Spray 0.2% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 30 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Cement Mortar Strength (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0049] Example 8 A preparation method of a grinding aid for producing cement clinker powder comprises the following steps: Take the following raw materials: 10 parts by weight of ethylene glycol, 10 parts by weight of triethanolamine, 3 parts by weight of ethyl orthosilicate, 1.5 parts by weight of 400-mesh carbide slag powder, 0.5 parts by weight of sodium lignin sulfonate, and 1 part by weight of 400-mesh calcium stearate powder. Mix the above raw materials and quickly stir and disperse them evenly to obtain a grinding aid.

[0050] Spray 0.4% of the grinding aid prepared in this embodiment evenly on ordinary Portland cement clinker, and then let it stand for 1 minute. After completion, grind it in a ball mill for 25 minutes to obtain cement clinker powder. Then, according to GB / T26748-2011 "Cement Grinding Aids", the 45μm sieve residue and specific surface area of ​​the cement clinker powder are tested to measure the grinding aid effect. In addition, according to GBT 17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)", the 3d compressive strength of the above-mentioned cement clinker powder is tested to measure its early strength. The test results are shown in the following table: .

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A grinding aid for producing cement clinker powder, characterized in that: The grinding aid comprises: 20-27 parts by weight of a mixture of hydrogen peroxide and polyol, 3-6 parts by weight of ethyl orthosilicate, 1.5-2.4 parts by weight of a solid calcium source, 0.5-0.75 parts by weight of lignin sulfonate, and 1-2 parts by weight of modified calcium stearate.

2. The grinding aid for producing cement clinker powder according to claim 1, characterized in that: The polyol includes at least one of ethylene glycol, propylene glycol and glycerol.

3. The grinding aid for producing cement clinker powder according to claim 1, characterized in that: The solid calcium source includes at least one of calcium oxide, calcium hydroxide and carbide slag; optionally, the particle size of the solid calcium source is not less than 400 meshes.

4. The grinding aid for producing cement clinker powder according to claim 1, characterized in that: The lignin sulfonate includes at least one of sodium lignin sulfonate and calcium lignin sulfonate.

5. The grinding aid for producing cement clinker powder according to claim 1, characterized in that: The modified calcium stearate is obtained by mixing calcium stearate with an ethanol solution of a polycarboxylate water-reducing agent and then grinding the mixture.

6. The grinding aid for producing cement clinker powder according to claim 5, characterized in that: The ratio of the calcium stearate to the ethanol solution of the polycarboxylate water reducer is 1g:0.4-0.7ml.

7. The grinding aid for producing cement clinker powder according to claim 6, characterized in that: The mass fraction of the polycarboxylate water-reducing agent in the ethanol solution is 2-3.5%; the mass fraction of the ethanol solution is not less than 80%; optionally, the particle size of the calcium stearate is not less than 400 meshes.

8. The grinding aid for producing cement clinker powder according to any one of claims 1 to 7, characterized in that: The mass fraction of the hydrogen peroxide solution in the mixture is 20-30%.

9. The method for using the grinding aid for producing cement clinker powder according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: spraying the grinding aid evenly on the cement clinker and then letting it stand, and then grinding the cement clinker.

10. The method for using a grinding aid for producing cement clinker powder according to claim 9, characterized in that: The grinding aid is added to the cement clinker in an amount of 0.2-0.4% of its mass; optionally, the standing time is 1-2 minutes.

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