Grinding aid for efficiently preparing limestone powder and preparation method of grinding aid

Abstract

The invention discloses a grinding aid for efficiently preparing limestone powder and a preparation method of the grinding aid, and belongs to the technical field of limestone powder preparation. The grinding aid is prepared from the following raw materials: 10-30 parts of phosphate amine salt, 1-5 parts of sodium n-alkyl benzene sulfonate, 1-3 parts of ionic liquid, 1-5 parts of La < 3 + > doped CeO2 nanoparticles, 1-3 parts of a permeation component, 5-15 parts of a dispersion component and 40-80 parts of water. Wherein the phosphate amine salt is dodecyl phosphate diethanolamine salt, the linear alkyl sodium benzene sulfonate is sodium tetradecyl benzene sulfonate, the ionic liquid is 1-butyl-3-methylimidazole bis (trifluoromethanesulfonyl) imide salt, the permeation component is sec-octyl alcohol polyoxyethylene ether, and the dispersion component comprises dipropylene glycol and dimethylethanolamine. The invention relates to 2-amino-2-methyl-1-propanol and a preparation method thereof. According to the grinding aid disclosed by the invention, through the synergistic effect of various components, the grinding aid is fully mixed with limestone and permeates into surface gaps of the limestone, so that the surface tension is effectively reduced, the crack propagation is promoted, the limestone powder fineness is improved, the grinding efficiency is improved, and the grinding energy consumption is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of limestone powder preparation, and particularly relates to a grinding aid for efficiently preparing limestone powder and a preparation method thereof. Background Art

[0002] Limestone, primarily composed of calcium carbonate, is abundant and widely distributed. Finely ground limestone powder has diverse applications, including as a flue gas desulfurizer, effectively reducing the sulfur content in industrial waste gas; as a concrete admixture, improving concrete properties; and as a key slag-forming agent in steel mills, facilitating the smooth operation of the steelmaking process. Furthermore, limestone powder is often used as a filler in industries such as plastics, rubber, and papermaking, reducing costs and improving product properties. In recent years, demand for cement has gradually shrunk, with cement grinding systems in some regions experiencing annual equipment utilization rates of less than 40%, leaving significant capacity idle. The equipment and facilities used to produce limestone powder and cement are highly compatible, and many cement plants are leveraging their existing resources to develop limestone powder grinding operations. Compared to cement, limestone powder exhibits unique physical properties: high viscosity, making it prone to sticking; strong electrostatic attraction, making it prone to adsorbing to equipment surfaces during production; and poor flowability, complicating material transportation and processing. These characteristics necessitate the addition of grinding aids when grinding limestone powder for stable production. At present, there are few reports on the application of special grinding aids for limestone grinding. Summary of the Invention

[0003] In view of the above problems, the present invention provides a grinding aid suitable for limestone, which can increase the fineness of limestone powder, improve the grinding efficiency and reduce the grinding energy consumption.

[0004] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0005] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 10-30 parts of phosphate amine salt, 1-5 parts of linear alkylbenzene sodium sulfonate, 1-3 parts of ionic liquid, La 3+ 1-5 parts of doped CeO2 nanoparticles, 1-3 parts of infiltration components, 5-10 parts of dispersion components, and 40-80 parts of water.

[0006] Furthermore, the phosphate amine salt is an alkyl phosphate amine salt.

[0007] Furthermore, the phosphate amine salt is dodecyl phosphate diethanolamine salt.

[0008] Furthermore, the linear alkylbenzene sulfonate is sodium tetradecylbenzene sulfonate.

[0009] Furthermore, the ionic liquid is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt.

[0010] Furthermore, the penetrating component is polyoxyethylene octanol ether.

[0011] Furthermore, the dispersing component includes dipropylene glycol, dimethylethanolamine, and 2-amino-2-methyl-1-propanol, and the weight ratio of the three is (10-20): (2-5): 1.

[0012] Furthermore, the La 3+ The preparation method of doped CeO2 nanoparticles is:

[0013] (1) Cerium nitrate hexahydrate and lanthanum nitrate hexahydrate were mixed and dissolved in deionized water, and 0.1% wt of PVP was added to obtain a mixed solution A;

[0014] (2) Add NH4HCO3 dissolved in deionized water to obtain mixed solution B, and slowly add mixed solution B to mixed solution A at 2 mL / min. Stir in a 50°C water bath during the addition process. Stop adding when the pH value stabilizes at 8.5. Aged for 2 h, collect the precipitate by centrifugation, and wash with deionized water and ethanol three times each.

[0015] (3) The precipitate was vacuum dried at 60 °C for 12 h, placed in a muffle furnace, and heated to 300 °C at 2 °C / min in a nitrogen atmosphere, kept warm for 2 h, and then heated to 550 °C at 5 °C / min, kept warm for 2 h to obtain La 3+ Doped CeO2 nanoparticles.

[0016] Furthermore, in step (1), Ce 4+ :La 3+ Mixed in a molar ratio of (95-99): (1-5), Ce 4+ and La 3+ The volume ratio of the total mole of metal ions to deionized water is 0.1 mol: 200 mL; the amount of NH4HCO3 used in step (2) is Ce 4+ and La 3+ The molar volume ratio of NH4HCO3 to deionized water is 0.9 mol: 100 ml, and the amount of PVP added is 0.1% of the total mass of cerium nitrate hexahydrate and lanthanum nitrate hexahydrate.

[0017] Furthermore, the Ce 4+ :La 3+ Mix according to the molar ratio of 19:1.

[0018] A method for preparing a grinding aid for efficiently preparing limestone powder comprises the following steps:

[0019] S1: Add water to a reactor, heat to 40-50°C and stir, slowly add sodium linear alkylbenzene sulfonate and stir until completely dissolved, add phosphate amine salt and stir evenly, add ionic liquid and permeation component again, and stir until completely dispersed;

[0020] S2: La 3+ Doped CeO2 nanoparticles were pre-mixed with the dispersed components, ultrasonicated for 10 min, and then slowly added to the reactor after mixing evenly and stirred for 30 min until no visible particles were found;

[0021] S3: The reactor was heated to 60°C, stirred at 5000 rpm for 10 min, then cooled to room temperature and passed through a 200-mesh sieve to obtain a grinding aid.

[0022] The invention also provides an application of preparing limestone powder by ball milling.

[0023] The mixing amount of the grinding aid of the present invention is 0.01-0.05% of the mass of the limestone.

[0024] Phosphate amine salt can improve the wettability of stone powder particles and promote the adsorption of grinding aids on the particle surface. Octanol polyoxyethylene ether can make the grinding aid better penetrate into the gaps on the stone powder surface and easily penetrate into the gaps between fine particles, which is conducive to the molecules of the grinding aid component spreading to more high-energy particle surfaces. It has a synergistic effect with the dispersed component (complex alcohol amine), which is conducive to the molecules of the complex alcohol amine spreading to more high-energy particle surfaces. It has a synergistic effect with the linear alkylbenzene sodium sulfonate and the dispersed component. The linear alkylbenzene sodium sulfonate can be adsorbed on the surface of limestone particles, reducing surface energy and reducing agglomeration between particles. The dispersed component has a relatively small molecular weight, and the hydroxyl groups therein are adsorbed on the surface of the stone powder particles, which has a significant dispersing effect on the stone powder fine grinding stage.

[0025] Ionic liquids are adsorbed on the surface of limestone particles to form a lubricating layer, reducing the agglomeration between particles. Under high grinding temperatures, the ionic liquids remain in liquid form and continue to exert a lubricating effect. When compounded with linear sodium alkylbenzene sulfonate, the ionic liquids can optimize the arrangement density of surfactants through electrostatic effects and improve dispersion efficiency.

[0026] CeO2 itself has high hardness, while La 3+ Doping can introduce lattice defects and enhance its surface activity. During the grinding process, nanoparticles act as grinding media, promoting the fracture of limestone particles through the local stress concentration effect. 3+ The doping of La accelerates the formation of surface oxygen vacancies, thereby enhancing the interface reaction with CaCO3, promoting its fracture and improving the grinding efficiency. 3+ Doping also increases the oxygen ion mobility of CeO2, inhibits the agglomeration of limestone particles through electrostatics, and makes the new surface more easily exposed to other components of the grinding aid.3+ Doping increases the phase transition temperature of CeO2, ensuring that the nanoparticles maintain structural stability and continue to function under conditions of mechanical friction heat generation.

[0027] Beneficial effects

[0028] The grinding aid of the present invention can be fully mixed with limestone through the synergistic effect of various components, and can penetrate into the cracks on the surface of limestone, effectively reducing the surface tension of particles, promoting crack expansion, increasing the fineness of limestone powder, improving grinding efficiency, and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the XRD pattern of the experimental limestone;

[0030] Figure 2 This is a diagram of a powder flowability tester;

[0031] Figure 3 This is the particle size distribution diagram of stone powder in the blank control group;

[0032] Figure 4 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Example 1;

[0033] Figure 5 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Example 2;

[0034] Figure 6 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Example 3;

[0035] Figure 7 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Example 4;

[0036] Figure 8 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Comparative Example 1;

[0037] Figure 9 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Comparative Example 2;

[0038] Figure 10 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Comparative Example 3;

[0039] Figure 11 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Comparative Example 4;

[0040] Figure 12 This is the particle size distribution diagram of the stone powder after grinding with the grinding aid in Comparative Example 5;

[0041] Figure 13 This is the particle size distribution diagram of stone powder after grinding with the grinding aid HLA-GO03. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be further described below with reference to specific embodiments, but is not limited thereto.

[0043] Example 1

[0044] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 10 parts of phosphate amine salt, 5 parts of linear alkylbenzene sodium sulfonate, 1 part of ionic liquid, and La 3+ 1 part of doped CeO2 nanoparticles, 1 part of infiltration component, 5 parts of dispersion component, and 40 parts of water.

[0045] The phosphate amine salt is dodecyl phosphate diethanolamine salt.

[0046] The linear alkylbenzene sulfonate is sodium tetradecylbenzene sulfonate.

[0047] The ionic liquid is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt.

[0048] The penetrating component is polyoxyethylene octanol ether.

[0049] The dispersing components include dipropylene glycol, dimethylethanolamine and 2-amino-2-methyl-1-propanol, and the weight ratio of the three is 20:2:1.

[0050] The La 3+ The preparation method of doped CeO2 nanoparticles is:

[0051] (1) Cerium nitrate hexahydrate and lanthanum nitrate hexahydrate were mixed and dissolved in deionized water, and 0.1% wt of PVP was added to obtain a mixed solution A;

[0052] (2) Add NH4HCO3 dissolved in deionized water to obtain mixed solution B, and slowly add mixed solution B to mixed solution A at 2 mL / min. Stir in a 50°C water bath during the addition process. Stop adding when the pH value stabilizes at 8.5. Aged for 2 h, collect the precipitate by centrifugation, and wash with deionized water and ethanol three times each.

[0053] (3) The precipitate was vacuum dried at 60 °C for 12 h, placed in a muffle furnace, and heated to 300 °C at 2 °C / min in a nitrogen atmosphere, kept warm for 2 h, and then heated to 550 °C at 5 °C / min, kept warm for 2 h to obtain La 3+ Doped CeO2 nanoparticles.

[0054] In the step (1), Ce 4+ :La 3+ Mixed in a molar ratio of 99:1, Ce 4+ and La 3+The volume ratio of the total mole of metal ions to deionized water is 0.1 mol: 200 mL; the amount of NH4HCO3 used in step (2) is Ce 4+ and La 3+ 3 times the total mole of metal ions, the molar volume ratio of NH4HCO3 to deionized water is 0.9mol:100ml.

[0055] A method for preparing a grinding aid for efficiently preparing limestone powder comprises the following steps:

[0056] S1: Add water to a reactor, heat to 40-50°C and stir, slowly add sodium linear alkylbenzene sulfonate and stir until completely dissolved, add phosphate amine salt and stir evenly, add ionic liquid and permeation component again, and stir until completely dispersed;

[0057] S2: La 3+ Doped CeO2 nanoparticles were pre-mixed with the dispersed components, ultrasonicated for 10 min, and then slowly added to the reactor after mixing evenly and stirred for 30 min until no visible particles were found;

[0058] S3: The reactor was heated to 60°C, stirred at 5000 rpm for 10 min, then cooled to room temperature and passed through a 200-mesh sieve to obtain a grinding aid.

[0059] Example 2

[0060] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 30 parts of phosphate amine salt, 1 part of linear alkylbenzene sodium sulfonate, 3 parts of ionic liquid, La 3+ 5 parts of doped CeO2 nanoparticles, 3 parts of infiltration components, 5 parts of dispersion components, and 80 parts of water.

[0061] The phosphate amine salt is dodecyl phosphate diethanolamine salt.

[0062] The linear alkylbenzene sulfonate is sodium tetradecylbenzene sulfonate.

[0063] The ionic liquid is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt.

[0064] The penetrating component is polyoxyethylene octanol ether.

[0065] The dispersing components include dipropylene glycol, dimethylethanolamine and 2-amino-2-methyl-1-propanol, and the weight ratio of the three is 10:5:1.

[0066] The La 3+ The preparation method of doped CeO2 nanoparticles is:

[0067] (1) Cerium nitrate hexahydrate and lanthanum nitrate hexahydrate were mixed and dissolved in deionized water, and 0.1% wt of PVP was added to obtain a mixed solution A;

[0068] (2) Add NH4HCO3 dissolved in deionized water to obtain mixed solution B, and slowly add mixed solution B to mixed solution A at 2 mL / min. Stir in a 50°C water bath during the addition process. Stop adding when the pH value stabilizes at 8.5. Aged for 2 h, collect the precipitate by centrifugation, and wash with deionized water and ethanol three times each.

[0069] (3) The precipitate was vacuum dried at 60 °C for 12 h, placed in a muffle furnace, and heated to 300 °C at 2 °C / min in a nitrogen atmosphere, kept warm for 2 h, and then heated to 550 °C at 5 °C / min, kept warm for 2 h to obtain La 3+ Doped CeO2 nanoparticles.

[0070] In the step (1), Ce 4+ :La 3+ Mixed in a molar ratio of 95:5, Ce 4+ and La 3+ The volume ratio of the total mole of metal ions to deionized water is 0.1 mol: 200 mL; the amount of NH4HCO3 used in step (2) is Ce 4+ and La 3+ 3 times the total mole of metal ions, the molar volume ratio of NH4HCO3 to deionized water is 0.9mol:100ml.

[0071] A method for preparing a grinding aid for efficiently preparing limestone powder comprises the following steps:

[0072] S1: Add water to a reactor, heat to 40-50°C and stir, slowly add sodium linear alkylbenzene sulfonate and stir until completely dissolved, add phosphate amine salt and stir evenly, add ionic liquid and permeation component again, and stir until completely dispersed;

[0073] S2: La 3+ Doped CeO2 nanoparticles were pre-mixed with the dispersed components, ultrasonicated for 10 min, and then slowly added to the reactor after mixing evenly and stirred for 30 min until no visible particles were found;

[0074] S3: The reactor was heated to 60°C, stirred at 5000 rpm for 10 min, then cooled to room temperature and passed through a 200-mesh sieve to obtain a grinding aid.

[0075] Example 3

[0076] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 20 parts of phosphate amine salt, 4 parts of linear alkylbenzene sodium sulfonate, 2 parts of ionic liquid, La 3+2 parts of doped CeO2 nanoparticles, 2 parts of infiltration components, 10 parts of dispersion components, and 60 parts of water.

[0077] The phosphate amine salt is dodecyl phosphate diethanolamine salt.

[0078] The linear alkylbenzene sulfonate is sodium tetradecylbenzene sulfonate.

[0079] The ionic liquid is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt.

[0080] The penetrating component is polyoxyethylene octanol ether.

[0081] The dispersing components include dipropylene glycol, dimethylethanolamine and 2-amino-2-methyl-1-propanol, and the weight ratio of the three is 15:4:1.

[0082] The La 3+ The preparation method of doped CeO2 nanoparticles is:

[0083] (1) Cerium nitrate hexahydrate and lanthanum nitrate hexahydrate were mixed and dissolved in deionized water, and 0.1% wt of PVP was added to obtain a mixed solution A;

[0084] (2) Add NH4HCO3 dissolved in deionized water to obtain mixed solution B, and slowly add mixed solution B to mixed solution A at 2 mL / min. Stir in a 50°C water bath during the addition process. Stop adding when the pH value stabilizes at 8.5. Aged for 2 h, collect the precipitate by centrifugation, and wash with deionized water and ethanol three times each.

[0085] (3) The precipitate was vacuum dried at 60 °C for 12 h, placed in a muffle furnace, and heated to 300 °C at 2 °C / min in a nitrogen atmosphere, kept warm for 2 h, and then heated to 550 °C at 5 °C / min, kept warm for 2 h to obtain La 3+ Doped CeO2 nanoparticles.

[0086] In the step (1), Ce 4+ :La 3+ Mixed in a molar ratio of 95:5, Ce 4+ and La 3+ The volume ratio of the total mole of metal ions to deionized water is 0.1 mol: 200 mL; the amount of NH4HCO3 used in step (2) is Ce 4+ and La 3+ 3 times the total molar amount of metal ions, the molar volume ratio of NH4HCO3 to deionized water is 0.9 mol:100 ml.

[0087] A method for preparing a grinding aid for efficiently preparing limestone powder comprises the following steps:

[0088] S1: Add water to a reactor, heat to 40-50°C and stir, slowly add sodium linear alkylbenzene sulfonate and stir until completely dissolved, add phosphate amine salt and stir evenly, add ionic liquid and permeation component again, and stir until completely dispersed;

[0089] S2: La 3+ Doped CeO2 nanoparticles were pre-mixed with the dispersed components, ultrasonicated for 10 min, and then slowly added to the reactor after mixing evenly and stirred for 30 min until no visible particles were found;

[0090] S3: The reactor was heated to 60°C, stirred at 5000 rpm for 10 min, then cooled to room temperature and passed through a 200-mesh sieve to obtain a grinding aid.

[0091] Example 4

[0092] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 12 parts of phosphate amine salt, 4 parts of linear alkylbenzene sodium sulfonate, 1 part of ionic liquid, and La 3+ 1 part of doped CeO2 nanoparticles, 2.3 parts of infiltration components, 8.5 parts of dispersion components, and 70 parts of water.

[0093] The phosphate amine salt is dodecyl phosphate diethanolamine salt.

[0094] The linear alkylbenzene sulfonate is sodium tetradecylbenzene sulfonate.

[0095] The ionic liquid is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt.

[0096] The penetrating component is polyoxyethylene octanol ether.

[0097] The dispersing components include dipropylene glycol, dimethylethanolamine and 2-amino-2-methyl-1-propanol, and the weight ratio of the three is 15:4:1.

[0098] The La 3+ The preparation method of doped CeO2 nanoparticles is:

[0099] (1) Cerium nitrate hexahydrate and lanthanum nitrate hexahydrate were mixed and dissolved in deionized water, and 0.1% wt of PVP was added to obtain a mixed solution A;

[0100] (2) Add NH4HCO3 dissolved in deionized water to obtain mixed solution B, and slowly add mixed solution B to mixed solution A at 2 mL / min. Stir in a 50°C water bath during the addition process. Stop adding when the pH value stabilizes at 8.5. Aged for 2 h, collect the precipitate by centrifugation, and wash with deionized water and ethanol three times each.

[0101] (3) The precipitate was vacuum dried at 60 °C for 12 h, placed in a muffle furnace, and heated to 300 °C at 2 °C / min in a nitrogen atmosphere, kept warm for 2 h, and then heated to 550 °C at 5 °C / min, kept warm for 2 h to obtain La 3+ Doped CeO2 nanoparticles.

[0102] In the step (1), Ce 4+ :La 3+ Mixed in a molar ratio of 99:1, Ce 4+ and La 3+ The volume ratio of the total mole of metal ions to deionized water is 0.1 mol: 200 mL; the amount of NH4HCO3 used in step (2) is Ce 4+ and La 3+ 3 times the total molar amount of metal ions, the molar volume ratio of NH4HCO3 to deionized water is 0.9 mol:100 ml.

[0103] A method for preparing a grinding aid for efficiently preparing limestone powder comprises the following steps:

[0104] S1: Add water to a reactor, heat to 40-50°C and stir, slowly add sodium linear alkylbenzene sulfonate and stir until completely dissolved, add phosphate amine salt and stir evenly, add ionic liquid and permeation component again, and stir until completely dispersed;

[0105] S2: La 3+ Doped CeO2 nanoparticles were pre-mixed with the dispersed components, ultrasonicated for 10 min, and then slowly added to the reactor after mixing evenly and stirred for 30 min until no visible particles were found;

[0106] S3: The reactor was heated to 60°C, stirred at 5000 rpm for 10 min, then cooled to room temperature and passed through a 200-mesh sieve to obtain a grinding aid.

[0107] Comparative Example 1

[0108] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 20 parts of phosphate amine salt, 4 parts of linear alkylbenzene sodium sulfonate, 2 parts of ionic liquid, La 3+ 2 parts of doped CeO2 nanoparticles, 10 parts of dispersed components, and 60 parts of water.

[0109] Compared with Example 3, this comparative example uses the same raw materials and steps as Example 3 except that the penetrating component, polyoxyethylene octanol ether, is not added.

[0110] Comparative Example 2

[0111] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 4 parts of linear alkylbenzene sulfonate, 2 parts of ionic liquid, La 3+2 parts of doped CeO2 nanoparticles, 2 parts of infiltration components, 10 parts of dispersion components, and 60 parts of water.

[0112] Compared with Example 3, this comparative example uses the same raw materials and steps as Example 3 except that ammonium phosphate dodecyl phosphate diethanolamine salt is not added.

[0113] Comparative Example 3

[0114] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 20 parts of phosphate amine salt, 4 parts of linear alkylbenzene sodium sulfonate, 2 parts of ionic liquid, La 3+ 2 parts of doped CeO2 nanoparticles, 2 parts of infiltration components, 10 parts of glycerol, and 60 parts of water.

[0115] Compared with Example 3, this comparative example is the same as Example 3 except that the dispersing component is replaced with glycerol. The other raw materials and steps are the same as Example 3.

[0116] Comparative Example 4

[0117] A grinding aid for efficiently preparing limestone powder, comprising the following raw materials in parts by weight: 20 parts of phosphate amine salt, 4 parts of linear alkylbenzene sodium sulfonate, La 3+ 2 parts of doped CeO2 nanoparticles, 2 parts of infiltration components, 10 parts of dispersion components, and 60 parts of water.

[0118] Compared with Example 3, this comparative example is the same as Example 3 except that no ionic liquid is added. The other raw materials and steps are the same as Example 3.

[0119] Comparative Example 5

[0120] A grinding aid for efficiently preparing limestone powder comprises the following raw materials in parts by weight: 20 parts of phosphate amine salt, 4 parts of linear alkylbenzene sodium sulfonate, 2 parts of ionic liquid, 2 parts of penetrating component, 10 parts of dispersing component and 60 parts of water.

[0121] This comparative example is compared with Example 3, except that La is not added. 3+ Except for doping CeO2 nanoparticles, the rest of the raw materials and steps are the same as those in Example 3.

[0122] Performance Testing

[0123] To further verify the effectiveness of the grinding aid for limestone powder preparation of the present invention, the grinding aids of Examples 1-4 and Comparative Examples 1-5 and cement grinding aid HLA-GO03 were sprayed on the surface of limestone at a dosage of 0.03% of the mass of the limestone. A blank control was set up, i.e., no grinding aid was added. The various properties of the two controls were statistically analyzed and compared:

[0124] The limestone was first crushed into stones with a particle size of no more than 6 mm. The limestone used in the experiment was taken from Jining Hailuo. Its XRD spectrum is shown in Figure 15 kg of limestone was weighed for each test group, and the grinding aids of Examples 1-4 and Comparative Examples 1-5, as well as our company's cement grinding aid HLA-GO03, were added according to the respective proportions. A blank control was used for comparison. The limestone powder was ground for 20 minutes in a 500 mm standard test mill (model SM-500, manufactured by Wuxi Jianyi Instrument Machinery Co., Ltd.). The fineness, flowability, and particle size distribution of the limestone powder were tested using the following specific testing methods:

[0125] Fineness (45μm sieve residue): Determined in accordance with GB / T 1345-2005 “Cement fineness test method, sieve analysis method”;

[0126] Liquidity: Use Figure 2 The powder flowability tester shown above first uses a vibrator to vibrate and aggregate the stone powder in a conical flask. The conical flask is then rotated 180 degrees and placed in a detector. The conical flask is rotated to destroy its compacted state. The number of rotations (compaction index) is used to characterize the stone powder flowability. Each test is repeated 6 times and the average value is taken. The larger the compaction index, the worse the flowability, and the smaller the compaction index, the better the flowability.

[0127] Powder particle size distribution: measured in accordance with JC / T721-2006 “Determination of cement particle size distribution - Laser method”, using the HELOS&RODOS dry laser particle size analyzer from Sympatec, Germany.

[0128] The test results are shown in Table 1.

[0129] Table 1 Comparison of grinding aid effects

[0130]

[0131]

[0132] As shown in Table 1, the use of the grinding aids of Examples 1-4 of the present invention effectively reduced the 45 μm sieve residue and increased the specific surface area of ​​the stone powder, indicating that the grinding efficiency can be improved. In addition, compared with the blank, the stone powder compaction index was effectively reduced, indicating that the stone powder grinding aid can improve the fluidity of the limestone powder.

[0133] Industrial application test

[0134] The stone powder grinding aid of the present invention was tested in an open-circuit grinding system with roller press pre-crushing in Huainan, Jiangsu Province. The mill was a Φ3.2*13 two-bin mill. The performance of the stone powder grinding aid was verified by comparing it with the original cement grinding aid and the grinding aid without any additives. The test data are shown in Table 2.

[0135] Table 2 Industrial test data

[0136] project Taiwan production (t / h) Average fineness (%) Process power consumption (kwh / t) Mill outlet temperature (℃) blank 66 10.2 38.8 126 HLA-GO03 80 9.7 36.2 103 Stone powder grinding aid (Example 3) 95 9.4 32.3 77

[0137] When the stone powder grinding aid is added to grind the stone powder, the mill working condition is good, no paste grinding and saturation grinding phenomenon occurs, the operation is stable, and the product quality is under control. Compared with the blank and the control using the cement grinding aid HLA-GO03, the production capacity of the grinding aid of Example 3 is increased by 44% and 19%, and the power consumption per ton is reduced by 6.5 kwh / t and 3.9 kwh / t. The production indicators and costs are significantly better than those without using the grinding aid and using the cement grinding aid.

[0138] It should be noted that the above embodiments are only some of the preferred embodiments of the present invention, and not all of them. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present invention.

Claims

1. A grinding aid for efficiently preparing limestone powder, characterized in that: The raw materials include the following parts by weight: 10-30 parts of phosphate amine salt, 1-5 parts of linear alkylbenzene sulfonate sodium, 1-3 parts of ionic liquid, La 3+ 1-5 parts of doped CeO2 nanoparticles, 1-3 parts of infiltration components, 5-15 parts of dispersion components, and 40-80 parts of water.

2. The grinding aid for efficiently preparing limestone powder according to claim 1, wherein The phosphate amine salt is an alkyl phosphate amine salt.

3. The grinding aid for efficiently preparing limestone powder according to claim 2, wherein The phosphate amine salt is dodecyl phosphate diethanolamine salt.

4. The grinding aid for efficiently preparing limestone powder according to claim 1, wherein The linear alkylbenzene sulfonate is sodium tetradecylbenzene sulfonate.

5. The grinding aid for efficiently preparing limestone powder according to claim 1, wherein The ionic liquid is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt.

6. The grinding aid for efficiently preparing limestone powder according to claim 1, wherein The penetrating component is polyoxyethylene octanol ether.

7. The grinding aid for efficiently preparing limestone powder according to claim 1, wherein The dispersing components include dipropylene glycol, dimethylethanolamine and 2-amino-2-methyl-1-propanol, and the weight ratio of the three is (10-20): (2-5):

1.

8. The grinding aid for efficiently preparing limestone powder according to claim 1, characterized in that: The La 3+ The preparation method of doped CeO2 nanoparticles is: (1) Cerium nitrate hexahydrate and lanthanum nitrate hexahydrate were mixed and dissolved in deionized water, and 0.1% wt of PVP was added to obtain a mixed solution A; (2) Add NH4HCO3 dissolved in deionized water to obtain mixed solution B, and slowly add mixed solution B to mixed solution A at 2 mL / min. Stir in a 50°C water bath during the addition process. Stop adding when the pH value stabilizes at 8.

5. Aged for 2 h, collect the precipitate by centrifugation, and wash with deionized water and ethanol three times each. (3) The precipitate was vacuum dried at 60 °C for 12 h, placed in a muffle furnace, and heated to 300 °C at 2 °C / min in a nitrogen atmosphere, kept warm for 2 h, and then heated to 550 °C at 5 °C / min, kept warm for 2 h to obtain La 3+ Doped CeO2 nanoparticles.

9. The grinding aid for efficiently preparing limestone powder according to claim 8, wherein In the step (1), Ce 4 + :La 3+ Mixed in a molar ratio of (95-99): (1-5), Ce 4+ and La 3+ The volume ratio of the total mole of metal ions to deionized water is 0.1 mol: 200 mL; the amount of NH4HCO3 used in step (2) is Ce 4+ and La 3+ 3 times the total mole of metal ions, the molar volume ratio of NH4HCO3 to deionized water is 0.9mol:100ml.

10. A method for preparing a grinding aid for efficiently preparing limestone powder according to claim 1-9, characterized in that: The method comprises the following steps: S1: Add water to a reactor, heat to 40-50°C and stir, slowly add sodium linear alkylbenzene sulfonate and stir until completely dissolved, add phosphate amine salt and stir evenly, add ionic liquid and permeation component again, and stir until completely dispersed; S2: La 3+ Doped CeO2 nanoparticles were pre-mixed with the dispersed components, ultrasonicated for 10 min, and then slowly added to the reactor after mixing evenly and stirred for 30 min until no visible particles were found; S3: The reactor was heated to 60°C, stirred at 5000 rpm for 10 min, then cooled to room temperature and passed through a 200-mesh sieve to obtain a grinding aid.

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