A high-efficiency grinding aid for cement and its preparation method

Abstract

The invention discloses a high-efficiency grinding-aid mineralized material for cement and a preparation method thereof. The grinding-aid mineralized material is compounded from a polyol amine component, an organic grinding-aid component, a sugar component, an inorganic salt component and water, and is applied to cement production to promote cement clinker hydration, stimulate the activity of cement admixtures, increase the hourly output of cement mills, and improve cement quality. On the basis of existing grinding aids, the amount of cement clinker can be further reduced, the amount of cement admixtures can be increased, the cost of cement production can be reduced, the energy consumption of cement production can be reduced, and the carbon emission of cement production can be reduced.

Description

Technical Field

[0001] The invention relates to a high-efficiency grinding-aiding mineralized material for cement and a preparation method thereof, belonging to the technical field of cement production. Background Art

[0002] Cement is the basic raw material for general civil engineering projects, and the cement industry is inseparable from economic construction. According to incomplete statistics, my country's annual cement production has exceeded 2 billion tons in recent years, ranking first in the world for many consecutive years. The cement industry is a high-energy-consuming industry. In the production process, it not only consumes a lot of energy, but also emits a large amount of CO2, NO and other gases. As a major industrial carbon emitter, how to reduce carbon emissions in the production process has become an important task for every cement production company. The cement used in general civil engineering projects is silicate cement, which is made of limestone and clay as the main raw materials. It is crushed, batched, and ground into raw materials, and then fed into cement kilns to calcine into clinker, and then the clinker is ground with an appropriate amount of gypsum (mixed materials and admixtures may also be added). By reducing the amount of clinker in the cement production process, it can effectively reduce cement production costs, energy consumption, and cement carbon emissions. At present, cement production companies mostly adopt the method of adding cement grinding aids during the production process to reduce the amount of cement clinker and increase the amount of admixtures, which has achieved the goal of reducing cement production costs, reducing production energy consumption, and reducing carbon emissions.

[0003] At present, cement grinding aids are cement admixtures mainly composed of organic substances such as alcoholamines and alcohols, and supplemented by sugars and inorganic salts. The effective components can promote cement hydration and improve cement strength. In the cement production process, adding 0.03%-0.1% of cement grinding aids to the cement mass can reduce the amount of cement clinker by about 5%, and replace it with an equal mass of admixtures. CN102432221A discloses a molasses-based cement grinding aid and a preparation method thereof, which is composed of 50-70 parts of molasses, 10-15 parts of caustic soda solution, 5-10 parts of triethanolamine, 5-20 parts of propylene glycol and 5-12 parts of sodium formate solution in weight. The above-mentioned molasses-based cement grinding aid significantly improves cement strength, reduces the cement clinker ratio by 5-7%, and correspondingly increases the amount of cement admixture by 5-7%. CN103771752A discloses a composite cement grinding aid, which is prepared by the following ingredients in parts by weight: 5%-15% triethanolamine, 20%-30% diisopropanolamine, 15%-20% polyolamine, 5%-10% sodium polyphosphate, 10%-20% lignin sulfonate, 5%-10% molasses, and the balance is water. The composite cement grinding aid has the grinding aid effect of traditional grinding aids, can significantly improve the fluidity and dispersibility of materials in the mill, reduce the viscosity of materials, change the particle gradation in the mill, stimulate the activity of materials, and reduce the amount of cement clinker by 4-10%.

[0004] It can be seen that although cement production enterprises can reduce the amount of clinker by about 5% by using cement grinding aids, it is still a long way from the ideal goal of cement enterprises. Due to the limited performance of cement grinding aids, it is difficult to further improve the quality of cement and further reduce the amount of cement clinker. Currently, most of the components of cement grinding aids are used to promote the hydration heat of cement clinker, and their stimulating effect on admixtures is limited, which leads to the inability to further reduce the amount of cement clinker in cement production, and thus the inability to further reduce carbon emissions. Summary of the invention

[0005] In view of the above problems, the present invention provides a high-efficiency grinding-aid mineralized material for cement and a preparation method thereof. The grinding-aid mineralized material is compounded from a polyol amine component, an organic grinding-aid component, a sugar component, an inorganic salt component and water, and is applied to cement production (the grinding-aid mineralized material of the present invention is further added to cement to which a grinding aid has been added). The grinding-aid mineralized material can promote the hydration of cement clinker, stimulate the activity of cement admixtures, increase the output of cement mill per hour, improve the quality of cement, and can further reduce the amount of cement clinker and increase the amount of cement admixtures on the basis of existing grinding aids, thereby reducing the cost of cement production, reducing the energy consumption of cement production and reducing the carbon emissions of cement production.

[0006] The technical scheme of the present invention is: a high-efficiency grinding aid mineralized material for cement, comprising the following components, by weight: 15-50 parts of polyol amine components, 10-20 parts of organic grinding aid components, 5-12 parts of sugar components, 5-10 parts of inorganic salt components and 10-60 parts of water.

[0007] The preferred ratio is: 18-30 parts of polyol amine components, 10-15 parts of organic grinding aid components, 5-12 parts of sugar components, 5-7 parts of inorganic salt components and 40-60 parts of water.

[0008] Furthermore, the organic grinding aid component is one of ethylene glycol (preferably by-product ethylene glycol), glycerol (preferably by-product glycerol), and papermaking waste liquid.

[0009] Furthermore, the above-mentioned carbohydrate component is one of sucrose, glucose and molasses.

[0010] Furthermore, the inorganic salt components are one or two of sodium chloride, calcium chloride, sodium thiosulfate and sodium thiocyanate.

[0011] Furthermore, the preparation method of the polyol amine component is as follows: add triethanolamine and alkali into a reaction container, stir and heat to 60°C-70°C, react for 1.5-2.5 hours, then dropwise add 1,2-dihaloethane, keep warm and stir for 3-8 hours, then heat to 80-100°C and continue to react for 2-6 hours to obtain the polyol amine component. The molar ratio of the ethanolamine, alkali and 1,2-dihaloethane is 2:1-2:0.9-1.0.

[0012] The reaction equation is shown below.

[0013]

[0014] Preferably, the base used in the preparation of the above-mentioned polyol amine is one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and triethylamine.

[0015] Preferably, the halogen in the 1,2-dihaloethane used in the preparation of the polyol amine is one of chlorine and bromine.

[0016] Furthermore, the preparation method of the above-mentioned high-efficiency grinding aid mineralized material for cement is specifically as follows: under stirring conditions, inorganic salt components are first added to water and mixed evenly, then sugar components are added and mixed evenly, and finally polyol amine components and organic grinding aid components are added and mixed evenly.

[0017] The polyol amine in the present invention can promote the hydration of cement clinker minerals, accelerate the generation of calcium hydroxide, increase the alkalinity of cement paste, and make the silicon oxygen bond and aluminum oxygen bond contained in the admixture more easily break, so that the active components such as active silicon dioxide and active aluminum oxide in the cement admixture react with calcium hydroxide to generate hydrated calcium silicate, hydrated calcium aluminate or hydrated calcium sulfoaluminate, etc. to improve the quality of cement; by-product ethylene glycol, by-product glycerol, and papermaking waste liquid are used as grinding aid components as surfactants, which mainly play the role of reducing the surface energy of materials, accelerating the physical crushing speed, eliminating static electricity generated during physical grinding, and preventing physical After crushing, small cracks close and over-grinding of materials is reduced, thereby increasing the output of cement mill and reducing grinding power consumption; sucrose, glucose and molasses are used to adsorb calcium ions on the surface of the silicon-rich layer of cement particles in the early stage of complex cement hydration, thereby increasing the degree of cement hydration, reducing the porosity of hydration products and improving the later strength of cement; inorganic salts such as sodium chloride, calcium chloride, sodium thiosulfate and sodium thiocyanate can be adsorbed on the surface of the admixture during cement hydration to increase the pH of the pore solution, and cooperate with polyol amines to accelerate the dissolution of silicon oxide and aluminum oxide in the admixture, thereby stimulating activity.

[0018] Usage: Add the grinding aid mineral material of the present invention to the cement to which the grinding aid has been added. The adding method is: in the cement grinding process, add the high-efficiency grinding aid mineral material for cement in an amount of 0.03%-0.1%.

[0019] The following points should be noted when using this product: 1. The amount of high-efficiency grinding aid mineralized material used in cement is calculated based on the total mass of cement; 2. The incorporation method is internal incorporation, that is, it is measured and added into the mill together with other raw materials during the cement grinding process; 3. This product should be stored in a cool and ventilated place to prevent rain and exposure.

[0020] The beneficial effects of the present invention are:

[0021] 1. The present invention uses polyol amine components, organic grinding aid components, sugar components, inorganic salt components and water to compound the mineralized material. Through the coordinated promotion effect between the components, the quality of cement can be improved, the amount of cement clinker can be reduced, the amount of admixture can be increased, the output of cement grinding can be increased, and the power consumption can be reduced, thereby achieving the purpose of reducing energy consumption in cement production and reducing carbon emissions in cement production. Adding 0.03%-0.1% in the cement production process can further reduce the amount of cement clinker by 3-6% and increase the output of cement mill by more than 8%.

[0022] 2. If Figure 2 As shown, the produced cement can be used in concrete to significantly improve the compactness of concrete, thereby improving the overall durability of concrete. In addition, the production process of the product is simple, and the product storage period is more than one year, which is convenient for promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the 28-day scanning electron microscope image of blank P·C42.5 cement used as raw material to further prepare C30 concrete;

[0024] Figure 2 28-day scanning electron microscope image of C30 concrete prepared by adding P·C42.5 cement with high-efficiency grinding aid mineralizer as raw material. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions in the present application, the present invention is further described below in conjunction with embodiments. The described embodiments are only a part of the embodiments of the present application, not all of them, and the present invention is not limited to the following embodiments.

[0026] Embodiment 1:

[0027] Preparation of polyol amines: Add 2 mol of triethanolamine and 1.5 mol of sodium hydroxide to a reaction flask, stir and heat to 60°C-70°C within 30 minutes, react for 2 hours and continuously add 0.95 mol of 1,2-dichloroethane, keep warm and stir for 5-6 hours, then heat to 80-100°C and continue to react for 4 hours to obtain polyol amines.

[0028] Production of high-efficiency grinding aid mineralized material for cement: first, pour 450 kg of water and 50 kg of sodium chloride into a blender, stir for 10 minutes to fully dissolve them, then add 100 kg of glucose into the blender, stir for 10 minutes to fully dissolve them; at the same time, pour 150 kg of by-product ethylene glycol and 250 kg of polyol amine into the blender and continue stirring for 10 minutes to obtain the high-efficiency grinding aid mineralized material for cement of the present application.

[0029] Test example: Comparative test using the high-efficiency grinding aid mineralized material for cement in this application

[0030] During the cement grinding process, the high-efficiency cement grinding aid mineralizing material obtained in Example 1 was added thereto at a dosage of 0.05%. Standard small mill, 5kg per mill.

[0031] The proportion of blank P·C42.5 cement is (by mass): 75% clinker, 5% desulfurized gypsum, 5% limestone, 7% slag, 8% fly ash, and 0.05% HY-A cement grinding aid. The activity of fly ash is about 75%, the activity of slag is about 80%, the 3-day compressive strength of clinker is about 28MPa, and the 28-day compressive strength is about 53MPa.

[0032] The proportion of P·C42.5 cement is (by mass): 70% clinker, 5% desulfurized gypsum, 7% limestone, 8% slag, 10% fly ash, plus 0.05% HY-A cement grinding aid and 0.05% high-efficiency grinding aid mineralized material.

[0033] Blank P·C42.5 cement without high-efficiency grinding aid mineralized material was used as the reference sample, and P·C42.5 cement with 0.05% high-efficiency grinding aid mineralized material was used as the comparison sample, with the same grinding time (30 minutes), cement mortar strength test standard GB / T17671-1999, fineness test standard: GB / T1345-2005. Specific small grinding test results are shown in Table 1.

[0034] Table 1: Effect of the high-efficiency grinding-aiding mineralized material of the present invention on P·C42.5 cement Small mill test results

[0035]

[0036]

[0037] As can be seen from Table 1, after using the high-efficiency grinding-aiding mineralized material for cement of the present invention, the cement fineness of 45μm sieve residue is significantly reduced, the decline reaches 24.3%, the cement specific surface area is slightly increased, the cement standard consistency is increased by 0.4% (much lower than 1%), and the initial setting and final setting of cement setting time are delayed by 10 minutes and 21 minutes respectively, which is related to the further reduction of cement clinker and the further increase of admixture dosage. Compared with the benchmark cement, the compressive strength of cement increases by 0.9MPa in 3 days and 2.2MPa in 28 days. It can be seen that, using the high-efficiency grinding-aiding mineralized material for cement of the present invention, the cement quality is slightly improved compared with the benchmark under the condition of reducing 5% clinker.

[0038] The blank P·C42.5 cement and the P·C42.5 cement with high-efficiency grinding aid mineralizer added were used as raw materials to further prepare C30 concrete. The 28-day scanning electron microscope images of the concrete were as follows: Figure 1 , Figure 2 As shown in the figure, it can be seen from the comparison that cement with high-efficiency grinding aid mineralized materials added to concrete can significantly improve the density of concrete, thereby improving its durability.

[0039] Example 2: High-efficiency grinding aid mineralized material for cement production

[0040] First, pour 460 kg of water and 60 kg of calcium chloride into a blender and stir for 10 minutes to fully dissolve them. Then add 120 kg of sucrose into the blender and stir for 10 minutes to fully dissolve them. At the same time, pour 100 kg of by-product propylene glycol and 260 kg of polyol amine into the blender and continue stirring for 10 minutes to obtain the high-efficiency grinding aid mineralized material for cement of the present application.

[0041] Example 3: High-efficiency grinding aid mineralized material for cement production

[0042] First, pour 500 kg of water and 50 kg of sodium chloride into a blender and stir for 10 minutes to fully dissolve them. Then add 50 kg of glucose into the blender and stir for 10 minutes to fully dissolve them. At the same time, pour 100 kg of by-product ethylene glycol and 300 kg of polyol amine into the blender and continue stirring for 10 minutes to obtain the high-efficiency grinding aid mineralized material for cement of the present application.

[0043] Example 4: High-efficiency grinding aid mineralized material for cement production

[0044] First, pour 600 kg of water and 70 kg of sodium chloride into a blender and stir for 10 minutes to fully dissolve them. Then add 50 kg of sucrose into the blender and stir for 10 minutes to fully dissolve them. At the same time, pour 100 kg of by-product ethylene glycol and 180 kg of polyol amine components into the blender and continue stirring for 10 minutes to obtain the high-efficiency grinding aid mineralized material for cement of the present application.

Claims

1. A high-efficiency grinding aid mineralized material for cement, characterized in that: The invention comprises the following components, calculated by weight: 18-30 parts of a polyol amine component, 10-15 parts of an organic grinding aid component, 5-12 parts of a sugar component, 5-7 parts of an inorganic salt component and 40-60 parts of water; The preparation method of the polyol amine component is as follows: add triethanolamine and alkali into a reaction container, stir and heat to 60°C-70°C, react for 1.5-2.5 hours, then drop 1,2-dihaloethane, keep warm and stir for 3-8 hours, then heat to 80-100°C and continue to react for 2-6 hours to obtain the polyol amine component; the halogen in the 1,2-dihaloethane is one of chlorine and bromine; The organic grinding aid component is one of ethylene glycol, glycerol, and papermaking waste liquid; The sugar component is one of sucrose, glucose and molasses; The inorganic salt component is one or two of sodium chloride, calcium chloride, sodium thiosulfate, and sodium thiocyanate; The molar ratio of the triethanolamine, the base and the 1,2-dihaloethane is 2:1-2:0.9-1.

0.

2. The high-efficiency grinding-aiding mineralized material for cement as claimed in claim 1, characterized in that: The base is one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and triethylamine.

3. The method for preparing the high-efficiency grinding-aiding mineralized material for cement according to claim 1 or 2, characterized in that: Under stirring conditions, first add the inorganic salt component into the water and mix evenly, then add the sugar component and mix evenly, and finally add the polyol amine component and the organic grinding aid component and mix evenly.

4. The method for using the high-efficiency grinding aid mineralized material for cement according to claim 1 or 2, characterized in that, High-efficiency grinding aid mineralized material for cement is further added to the cement to which grinding aid has been added. The adding method is: during the cement grinding process, add it at a dosage of 0.03%-0.1%.

Images