Cement raw material grinding aid as well as preparation method and application thereof

Abstract

The invention provides a cement raw material grinding aid as well as a preparation method and application thereof, and relates to the technical field of cement production, the cement raw material grinding aid comprises the following components: sodium polyacrylate, copper N, N-dibutyldithiocarbamate, metal salt and water; the weight-average molecular weight of the sodium polyacrylate is 200 to 5000; the sodium polyacrylate comprises at least one of sodium polyacrylate with the weight-average molecular weight of 200 to 800 and sodium polyacrylate with the weight-average molecular weight of 3000 to 4000; the metal salt comprises at least one of zinc nitrate, barium nitrate, lanthanum nitrate and cerium nitrate. The cement raw material grinding aid solves the technical problems of unstable grinding-aiding and yield-increasing effects and poor coal-saving effect of the cement raw material grinding aid in the prior art, and achieves the technical effects of remarkably improving the grinding-aiding and yield-increasing effects of the cement raw material, effectively reducing coal consumption and realizing stable application.

Description

Technical Field

[0001] The invention relates to the technical field of cement production, in particular to a cement raw material grinding aid and a preparation method and application thereof. Background Art

[0002] In recent years, energy conservation and emission reduction have become an important topic and urgent challenge for cement enterprises on their road to transformation and upgrading. In the cement production process, energy consumption in two key links is particularly significant: one is the raw material grinding stage, which involves grinding, mixing and grinding a large amount of limestone, clay raw materials and corrective raw materials to prepare raw materials, which consumes a huge amount of electricity; the other is the decomposition and calcination process of raw materials. After being pre-treated by the preheater and decomposition furnace, the raw materials need to be calcined in a kiln at up to 1450°C, which consumes a large amount of coal powder. How to effectively reduce the energy consumption of these links and achieve energy conservation and emission reduction is a problem that cement enterprises must face and solve during the transformation and upgrading process.

[0003] In order to improve the efficiency of raw material grinding, reduce power consumption and improve its burnability, the existing technology will add an appropriate amount of raw material grinding aids during the raw material grinding process. The surface active components such as lignin sulfonate, polyolamine and polyhydroxy alcohol in the raw material grinding aids can improve the grindability and dispersibility of the raw material, thereby reducing the current of the grinding roller motor and improving its stability, reducing the raw material fineness and increasing its specific surface area, increasing the raw material output, and reducing the power consumption of raw material grinding; at the same time, the organic acid salt in the raw material grinding aid will be adsorbed on the surface of the raw material fine particles, which can reduce the activation energy required for the decomposition of calcium carbonate, improve the decomposition rate and burnability of the raw material, and then reduce coal consumption, which has the effect of aiding grinding and saving coal.

[0004] However, the current cement raw meal grinding aid products are not mature. Although there are many types of grinding aids on the market, the effects of improving the grinding and production of cement raw meal and saving coal are still not ideal.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] One of the purposes of the present invention is to provide a cement raw meal grinding aid, which can significantly improve the grinding and production-enhancing effect of cement raw meal and effectively reduce coal consumption.

[0007] The second object of the present invention is to provide a method for preparing a cement raw material grinding aid, which has a simple process, high efficiency, high success rate and is suitable for industrial production.

[0008] The third object of the present invention is to provide an application of a cement raw material grinding aid, which is beneficial to reducing energy consumption in the cement production process and has a stable application effect.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0010] In the first aspect, a cement raw meal grinding aid comprises the following components:

[0011] Sodium polyacrylate, copper N,N-dibutyldithiocarbamate, metal salts, and water;

[0012] The weight average molecular weight of the sodium polyacrylate is 200-5000;

[0013] The sodium polyacrylate comprises at least one of sodium polyacrylate having a weight average molecular weight of 200-800 and sodium polyacrylate having a weight average molecular weight of 3000-4000;

[0014] The metal salt includes at least one of zinc nitrate, barium nitrate, lanthanum nitrate and cerium nitrate.

[0015] Furthermore, the components of the cement raw meal grinding aid also include lignin sulfonate.

[0016] Furthermore, the lignin sulfonate includes at least one of sodium lignin sulfonate and calcium lignin sulfonate.

[0017] Furthermore, the cement raw meal grinding aid comprises the following components in parts by weight:

[0018] 5-30 parts of sodium polyacrylate, 0.1-5 parts of copper N,N-dibutyldithiocarbamate, 5-15 parts of metal salt, 5-30 parts of lignin sulfonate, and 40-60 parts of water.

[0019] Furthermore, the cement raw meal grinding aid comprises the following components in parts by weight:

[0020] 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of water;

[0021] The weight ratio of the sodium polyacrylate with a weight average molecular weight of 200-800 to the sodium polyacrylate with a weight average molecular weight of 3000-4000 in the sodium polyacrylate is 4:1;

[0022] The weight ratio of zinc nitrate to cerium nitrate in the metal salt is 1:1.

[0023] Furthermore, the cement raw meal grinding aid comprises the following components in parts by weight:

[0024] 20 parts of sodium polyacrylate, 1 part of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 20 parts of sodium lignin sulfonate, and 54 parts of water;

[0025] The sodium polyacrylate is a sodium polyacrylate with a weight average molecular weight of 200-800;

[0026] The weight ratio of zinc nitrate to cerium nitrate in the metal salt is 1:1.

[0027] Furthermore, the cement raw meal grinding aid comprises the following components in parts by weight:

[0028] 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of water;

[0029] The sodium polyacrylate is a sodium polyacrylate with a weight average molecular weight of 3000-4000;

[0030] The weight ratio of barium nitrate to lanthanum nitrate in the metal salt is 1:1.

[0031] In a second aspect, a method for preparing the cement raw meal grinding aid according to any one of the above items comprises the following steps:

[0032] The components are mixed according to proportion to obtain the cement raw meal grinding aid.

[0033] Furthermore, the preparation method comprises the following steps:

[0034] Firstly, sodium polyacrylate, copper N,N-dibutyldithiocarbamate and water are mixed, and then metal salt and lignin sulfonate are added and mixed to obtain the cement raw material grinding aid.

[0035] A third aspect is the use of the cement raw meal grinding aid described in any one of the above items in cement grinding.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] The cement raw material grinding aid provided by the present invention can significantly improve the grinding aid and production improvement effect of cement raw material under the synergistic cooperation of sodium polyacrylate with a specific weight average molecular weight, N, N-dibutyl dithiocarbamate copper and a specific metal salt, and can also play an excellent coal-saving effect, and can achieve stable application; specifically, when sodium polyacrylates with different weight average molecular weights are matched, since sodium polyacrylate substances have high activity and are prone to continuous polymerization reaction to form flocculation and precipitation in the presence of certain metal ions, N, N-dibutyl dithiocarbamate copper is introduced as a polymerization inhibitor, which can improve the chemical stability of sodium polyacrylate substances with different weight average molecular weights, and thus is more conducive to making sodium polyacrylates with different weight average molecular weights play different roles. The two have the same effect; on the one hand, sodium polyacrylate with a weight average molecular weight of 200-2000 can play an excellent coating and dispersing role on raw material fine particles, which is beneficial to improving the uniformity of raw material powder particles. Compared with the use of lignin sulfonate alone, it can play a more stable and significant grinding aid, dispersion and production improvement effect; on the other hand, sodium polyacrylate with a weight average molecular weight of 3000-5000 can play an excellent dispersing role on metal salt ions. During the grinding process, the metal salt can be evenly dispersed on the surface of raw material fine particles so that it can be brought into the rotary kiln for co-calcination. The doping of specific metal salts can increase the vacancy defects in the structure, reduce the activation energy of the reaction, promote the formation of C3S minerals, and reduce the content of f-CaO in the clinker.

[0038] The preparation method of the cement raw material grinding aid provided by the invention has simple process, high efficiency and high success rate and is suitable for industrial production.

[0039] The application of the cement raw meal grinding aid provided by the present invention is beneficial to reducing energy consumption in the cement production process, and the application effect is stable. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] According to a first aspect of the present invention, there is provided a cement raw meal grinding aid, comprising the following components:

[0042] Sodium polyacrylate, copper N,N-dibutyldithiocarbamate, metal salts, and water;

[0043] Wherein, the weight average molecular weight of sodium polyacrylate is 200-5000;

[0044] The sodium polyacrylate comprises at least one of sodium polyacrylate having a weight average molecular weight of 200-800 and sodium polyacrylate having a weight average molecular weight of 3000-4000;

[0045] The metal salt includes but is not limited to at least one of zinc nitrate, barium nitrate, lanthanum nitrate and cerium nitrate.

[0046] The cement raw material grinding aid provided by the present invention can significantly improve the grinding aid and production improvement effect of cement raw material under the synergistic cooperation of sodium polyacrylate with a specific weight average molecular weight, N, N-dibutyl dithiocarbamate copper and a specific metal salt, and can also play an excellent coal-saving effect, and can achieve stable application; specifically, when sodium polyacrylates with different weight average molecular weights are matched, since sodium polyacrylate substances have high activity and are prone to continuous polymerization reaction to form flocculation and precipitation in the presence of certain metal ions, N, N-dibutyl dithiocarbamate copper is introduced as a polymerization inhibitor, which can improve the chemical stability of sodium polyacrylate substances with different weight average molecular weights, and thus is more conducive to making sodium polyacrylates with different weight average molecular weights play different roles. The two have the same effect; on the one hand, sodium polyacrylate with a weight average molecular weight of 200-2000 can play an excellent coating and dispersing role on raw material fine particles, which is beneficial to improving the uniformity of raw material powder particles. Compared with the use of lignin sulfonate alone, it can play a more stable and significant grinding aid, dispersion and production improvement effect; on the other hand, sodium polyacrylate with a weight average molecular weight of 3000-5000 can play an excellent dispersing role on metal salt ions. During the grinding process, the metal salt can be evenly dispersed on the surface of raw material fine particles so that it can be brought into the rotary kiln for co-calcination. The doping of specific metal salts can increase the vacancy defects in the structure, reduce the activation energy of the reaction, promote the formation of C3S minerals, and reduce the content of f-CaO in the clinker.

[0047] In a preferred embodiment, the components of the cement raw meal grinding aid further include but are not limited to lignin sulfonate.

[0048] In the present invention, lignin sulfonate includes but is not limited to at least one of sodium lignin sulfonate and calcium lignin sulfonate. Sodium polyacrylate and lignin sulfonate are used together to achieve stable and significant grinding aid, dispersion and production improvement effects.

[0049] In a preferred embodiment, the cement raw meal grinding aid comprises the following components in parts by weight:

[0050] 5-30 parts of sodium polyacrylate, 0.1-5 parts of copper N,N-dibutyldithiocarbamate, 5-15 parts of metal salt, 5-30 parts of lignin sulfonate, and 40-60 parts of water.

[0051] In the present invention, typical but non-limiting weight portions of sodium polyacrylate are, for example, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, and 30 parts; typical but non-limiting weight portions of copper N,N-dibutyldithiocarbamate are, for example, 0.1 parts, 0.5 parts, 1 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, and 5 parts; typical but non-limiting weight portions of metal salts are, for example, Typical but non-limiting weight portions of lignin sulfonate are, for example, 5, 10, 15, 20, 25, 30 parts; typical but non-limiting weight portions of water are, for example, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60 parts.

[0052] In the present invention, through the sodium polyacrylate composite metal salt dispersion technology, the metal salt is uniformly attached to the surface of the raw material fine particles, which can increase the vacancy defects in the structure, reduce the activation energy of the reaction, and further promote the formation of C3S minerals, and reduce the content of f-CaO in the clinker; in short, the cement raw material grinding aid of the present invention significantly improves the grinding effect of the raw material through the synergistic combination of each component and its specific weight ratio, effectively improves the dispersibility and fluidity of the particles, is conducive to increasing the specific surface area of ​​the raw material grinding and reducing the particle grinding fineness, significantly improves the grinding aid and production improvement effect of the cement raw material and effectively reduces the grinding power consumption.

[0053] In a preferred embodiment, the cement raw meal grinding aid comprises the following components in parts by weight:

[0054] 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of water;

[0055] Among them, the weight ratio of sodium polyacrylate with a weight average molecular weight of 200-800 to sodium polyacrylate with a weight average molecular weight of 3000-4000 in sodium polyacrylate can be 4:1, but is not limited thereto, which is more conducive to increasing the specific surface area of ​​raw material grinding, reducing the particle grinding fineness, and reducing the grinding power consumption;

[0056] The weight ratio of zinc nitrate to cerium nitrate in the metal salt can be 1:1, but is not limited thereto, and can further promote the formation of C3S minerals and reduce the content of f-CaO in the clinker.

[0057] In the present invention, the cement raw meal grinding aid comprises the following components in parts by weight:

[0058] 20 parts of sodium polyacrylate, 1 part of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 20 parts of sodium lignin sulfonate, and 54 parts of water;

[0059] Wherein, the sodium polyacrylate may be a sodium polyacrylate having a weight average molecular weight of 200-800;

[0060] The weight ratio of zinc nitrate to cerium nitrate in the metal salt may be 1:1.

[0061] In the present invention, the cement raw meal grinding aid comprises the following components in parts by weight:

[0062] 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of water;

[0063] Wherein, the sodium polyacrylate may be a sodium polyacrylate having a weight average molecular weight of 3000-4000;

[0064] The weight ratio of barium nitrate to lanthanum nitrate in the metal salt may be 1:1.

[0065] According to a second aspect of the present invention, there is provided a method for preparing the cement raw meal grinding aid described in any one of the above items, comprising the following steps:

[0066] The components are mixed in proportion to obtain a cement raw meal grinding aid.

[0067] The preparation method of the cement raw material grinding aid provided by the invention has simple process, high efficiency and high success rate and is suitable for industrial production.

[0068] In a preferred embodiment, the preparation method of cement raw meal grinding aid comprises the following steps:

[0069] Firstly, sodium polyacrylate, copper N,N-dibutyldithiocarbamate and water are mixed, and then metal salt and lignin sulfonate are added and mixed to obtain a cement raw material grinding aid.

[0070] In the present invention, the preparation method of cement raw meal grinding aid comprises the following steps: firstly, sodium polyacrylate, N,N-dibutyl copper dithiocarbamate and deionized water are mixed in proportion and stirred evenly, the stirring speed can be 800 rpm, the stirring time can be 30 minutes, and then metal salt and lignin sulfonate are added in proportion in sequence and mixed, and stirred evenly, so as to obtain cement raw meal grinding aid.

[0071] The specific mixing order of the components is more conducive to further improving the mixing effect of the materials and ensuring the preparation effect of the cement raw meal grinding aid.

[0072] According to a third aspect of the present invention, there is provided a use of any of the above-mentioned cement raw meal grinding aids in cement grinding.

[0073] The application of the cement raw meal grinding aid provided by the present invention is beneficial to reducing energy consumption in the cement production process, and the application effect is stable.

[0074] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.

[0075] Example 1

[0076] This embodiment provides a cement raw meal grinding aid, which is prepared from the following components in parts by weight:

[0077] 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of deionized water;

[0078] The sodium polyacrylate is sodium polyacrylate with a weight average molecular weight of 200-800 and sodium polyacrylate with a weight average molecular weight of 3000-4000;

[0079] Wherein, the weight ratio of sodium polyacrylate with a weight average molecular weight of 200-800 to sodium polyacrylate with a weight average molecular weight of 3000-4000 is 4:1;

[0080] The metal salts are zinc nitrate and cerium nitrate;

[0081] Wherein, the weight ratio of zinc nitrate to cerium nitrate is 1:1.

[0082] Example 2

[0083] This embodiment provides a cement raw meal grinding aid, which is prepared from the following components in parts by weight:

[0084] 20 parts of sodium polyacrylate, 1 part of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 20 parts of sodium lignin sulfonate, and 54 parts of deionized water;

[0085] Sodium polyacrylate is sodium polyacrylate with a weight average molecular weight of 200-800;

[0086] The metal salts are zinc nitrate and cerium nitrate;

[0087] Wherein, the weight ratio of zinc nitrate to cerium nitrate is 1:1.

[0088] Example 3

[0089] This embodiment provides a cement raw meal grinding aid, which is prepared from the following components in parts by weight:

[0090] 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of deionized water;

[0091] Sodium polyacrylate is sodium polyacrylate with a weight average molecular weight of 3000-4000;

[0092] The metal salts are barium nitrate and lanthanum nitrate;

[0093] Wherein, the weight ratio of barium nitrate to lanthanum nitrate is 1:1.

[0094] Example 4

[0095] This embodiment provides a cement raw material grinding aid, which is different from the embodiment 1 only in that this embodiment does not contain sodium lignin sulfonate;

[0096] The remaining compositions are the same as those in Example 1.

[0097] Example 5

[0098] This embodiment provides a cement raw material grinding aid, which is different from Embodiment 1 only in that in this embodiment, an equal amount of sodium lignin sulfonate is replaced by calcium lignin sulfonate;

[0099] The remaining compositions are the same as those in Example 1.

[0100] Example 6

[0101] This embodiment provides a cement raw material grinding aid, which is different from Embodiment 1 only in that the weight portion of sodium polyacrylate in this embodiment is 5 parts;

[0102] The remaining compositions are the same as those in Example 1.

[0103] Example 7

[0104] This embodiment provides a cement raw material grinding aid, which is different from Embodiment 1 only in that the weight portion of sodium polyacrylate in this embodiment is 18 parts;

[0105] The remaining compositions are the same as those in Example 1.

[0106] Example 8

[0107] This embodiment provides a cement raw meal grinding aid, which is different from the embodiment 1 only in that the weight parts of the metal salt in this embodiment are 10 parts;

[0108] The remaining compositions are the same as those in Example 1.

[0109] Example 9

[0110] This embodiment provides a cement raw meal grinding aid, which is different from the embodiment 1 only in that the weight parts of the metal salt in this embodiment are 15 parts;

[0111] The remaining compositions are the same as those in Example 1.

[0112] Example 10

[0113] This embodiment is a method for preparing the cement raw material grinding aid of Embodiments 1-9, comprising the following steps:

[0114] First, sodium polyacrylate, N,N-dibutyl copper dithiocarbamate and deionized water are mixed in proportion and stirred evenly at a stirring speed of 800 rpm for 30 min. Then, metal salt and lignin sulfonate are added in proportion and mixed evenly to obtain a cement raw material grinding aid.

[0115] Comparative Example 1

[0116] This comparative example provides a cement raw material grinding aid, which is different from Example 1 only in that an equal amount of sodium polyacrylate is replaced by a polymeric alcohol amine in this comparative example;

[0117] The remaining components are the same as those in Example 1, and the preparation method is similar to that in Example 10.

[0118] Comparative Example 2

[0119] This comparative example provides a cement raw meal grinding aid, which is different from Example 1 only in that in this comparative example, the metal salts (zinc nitrate and cerium nitrate) are replaced by sodium carbonate in equal amounts;

[0120] The remaining components are the same as those in Example 1, and the preparation method is similar to that in Example 10.

[0121] Comparative Example 3

[0122] This comparative example provides a cement raw material grinding aid, which is different from Example 1 only in that this comparative example does not contain N,N-dibutyl copper dithiocarbamate;

[0123] The remaining components are the same as those in Example 1, and the preparation method is similar to that in Example 10.

[0124] Comparative Example 4

[0125] This comparative example provides a cement raw material grinding aid, which is different from Example 1 only in that in this comparative example, an equal amount of N,N-dibutyldithiocarbamate copper is replaced by p-diphenol;

[0126] The remaining components are the same as those in Example 1, and the preparation method is similar to that in Example 10.

[0127] Test example

[0128] In order to verify the grinding effect and calcination effect of the grinding aid, the cement raw material grinding aid obtained in each embodiment and comparative example was tested respectively. The test results are shown in Table 1 and Table 2.

[0129] Test method (verification of grinding aid effect): Select the same batch of homogenized cement raw materials, add different raw material grinding aids to carry out small grinding test, grind for the same time, and measure the 80μm and 200μm sieve residue values ​​of the finished grinding products respectively;

[0130] Test method (to verify the calcination effect): Take the above-mentioned small-mill test sample powders mixed with different raw material grinding aids, add 1% of coal ash respectively, press the samples into tablets and put them into the experimental high-temperature furnace for calcination at 1450°C to obtain different clinker samples, and then determine the f-CaO (free calcium) content of the clinker.

[0131] Table 1 Grinding effect of cement raw meal grinding aid

[0132] project Grinding aid dosage (%) 80μm sieve residue (%) 200μm sieve residue (%) <![CDATA[Specific surface area (m 2 / kg)]]> Grinding time(s) Example 1 0.15 15.4 0.8 468 620 Example 2 0.15 16.0 1.0 461 620 Example 3 0.15 16.5 1.0 460 620 Example 4 0.15 15.9 1.0 455 620 Example 5 0.15 15.5 0.8 458 620 Example 6 0.15 17.0 0.9 452 620 Example 7 0.15 16.5 1.0 461 620 Example 8 0.15 15.6 0.8 465 620 Example 9 0.15 15.3 0.9 463 620 Comparative Example 1 0.15 17.1 0.8 444 620 Comparative Example 2 0.15 16.7 0.9 446 620 Comparative Example 3 0.15 17.1 0.9 452 620 Comparative Example 4 0.15 16.6 1.0 455 620

[0133] From the grinding result data in Table 1, it can be seen that the grinding aids of Examples 1-9 can achieve better grinding effect, optimize the fineness and specific surface area of ​​raw material grinding, and are better than the grinding aids of Comparative Examples 1-4. In particular, after adding the grinding aids of Examples 1-3, the fineness of raw material grinding is 15.4%, 16.0% and 16.5%, respectively, and the specific surface area is 468m 2 / kg, 461m 2 / kg and 460m 2 / kg, while after adding the grinding aids of Comparative Examples 1-2, the fineness of raw material grinding was 17.1% and 16.7% respectively, and the specific surface area was 444m 2 / kg and 446m 2 / kg, it can be seen that the grinding aids of Examples 1-3 can significantly optimize the fineness and specific surface area of ​​raw material grinding, and the effects achieved are significantly higher than those of the grinding aids of Comparative Examples 1-2.

[0134] Table 2 Calcination effect of cement raw meal grinding aid

[0135] project f-CaO (free calcium) / % Example 1 0.72 Example 2 0.88 Example 3 0.85 Example 4 0.84 Example 5 0.77 Example 6 0.89 Example 7 0.87 Example 8 0.84 Example 9 0.80 Comparative Example 1 2.62 Comparative Example 2 1.65 Comparative Example 3 1.89 Comparative Example 4 1.23

[0136] From the calcination result data in Table 2, it can be seen that the f-CaO content in the clinker fired by the raw materials into which the grinding aids of Examples 1-3 and Comparative Examples 1-2 were respectively added was 0.72%, 0.88%, 0.85%, 2.62% and 1.65%, respectively, which shows that the grinding aids of Examples 1-3 can significantly improve the burnability of the clinker. In short, the grinding aids of Examples 1-9 can significantly improve the burnability of the clinker, and the f-CaO content in the clinker is significantly reduced, which is significantly better than the grinding aids of Comparative Examples 1-4.

[0137] In summary, the cement raw meal grinding aid provided by the present invention can significantly improve the grinding effect of the raw meal under the coordinated cooperation of various components and their weight ratios, improve the dispersibility and fluidity of the particles, increase the specific surface area, reduce the particle fineness, and reduce the power consumption of grinding; the present invention utilizes the sodium polyacrylate composite metal salt dispersion technology to uniformly attach the metal salt to the surface of the raw meal fine particles, and the specific metal salt doping increases the vacancy defects in the structure, reduces the activation energy of the reaction, can promote the formation of C3S minerals, and reduce the content of f-CaO in the clinker.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cement raw meal grinding aid, characterized in that: Includes the following components: Sodium polyacrylate, copper N,N-dibutyldithiocarbamate, metal salts, and water; The weight average molecular weight of the sodium polyacrylate is 200-5000; The sodium polyacrylate comprises at least one of sodium polyacrylate having a weight average molecular weight of 200-800 and sodium polyacrylate having a weight average molecular weight of 3000-4000; The metal salt includes at least one of zinc nitrate, barium nitrate, lanthanum nitrate and cerium nitrate.

2. The cement raw meal grinding aid according to claim 1, characterized in that: The components of the cement raw material grinding aid also include lignin sulfonate.

3. The cement raw meal grinding aid according to claim 2, characterized in that: The lignin sulfonate includes at least one of sodium lignin sulfonate and calcium lignin sulfonate.

4. The cement raw meal grinding aid according to claim 3, characterized in that: The cement raw meal grinding aid comprises the following components by weight: 5-30 parts of sodium polyacrylate, 0.1-5 parts of copper N,N-dibutyldithiocarbamate, 5-15 parts of metal salt, 5-30 parts of lignin sulfonate, and 40-60 parts of water.

5. The cement raw meal grinding aid according to claim 4, characterized in that: The cement raw meal grinding aid comprises the following components by weight: 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of water; The weight ratio of the sodium polyacrylate with a weight average molecular weight of 200-800 to the sodium polyacrylate with a weight average molecular weight of 3000-4000 in the sodium polyacrylate is 4:

1.

6. The cement raw meal grinding aid according to claim 4, characterized in that: The cement raw meal grinding aid comprises the following components by weight: 20 parts of sodium polyacrylate, 1 part of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 20 parts of sodium lignin sulfonate, and 54 parts of water; The sodium polyacrylate has a weight average molecular weight of 200-800.

7. The cement raw meal grinding aid according to claim 4, characterized in that: The cement raw meal grinding aid comprises the following components by weight: 30 parts of sodium polyacrylate, 2 parts of N,N-dibutyl copper dithiocarbamate, 5 parts of metal salt, 10 parts of sodium lignin sulfonate, and 53 parts of water; The sodium polyacrylate has a weight average molecular weight of 3000-4000.

8. A method for preparing the cement raw meal grinding aid according to any one of claims 1 to 7, characterized in that: The following steps are involved: The components are mixed according to proportion to obtain the cement raw meal grinding aid.

9. The preparation method according to claim 8, characterized in that: The preparation method comprises the following steps: Firstly, sodium polyacrylate, copper N,N-dibutyldithiocarbamate and water are mixed, and then metal salt and lignin sulfonate are added and mixed to obtain the cement raw material grinding aid.

10. Use of the cement raw material grinding aid according to any one of claims 1 to 7 in cement grinding.