Preparation method and application of low-carbon cement mineralizer

Abstract

The invention discloses a preparation method and application of a low-carbon cement mineralizer, and relates to the field of cement mineralizer production.The preparation method comprises the steps that 40-60 parts by weight of industrial solid waste residues, 10-20 parts by weight of waste glass, 5-15 parts by weight of biomass charcoal, 10-30 parts by weight of a calcium-containing compound and 5-15 parts by weight of a magnesium-containing compound are selected as raw materials; after mixing, adding a dispersing agent accounting for 3-8% of the total weight of the raw materials, and grinding for 30-60 minutes by a ball mill (the ball-to-material ratio is (8-12): 1) to obtain a mixed material; calcining the mixed material in a rotary kiln at 800-1000 DEG C for 1-2 hours, quickly cooling (50-100 DEG C / min), ultrasonically dispersing in deionized water for 15-30 minutes under the ultrasonic frequency of 20-40 kHz and the power of 200-500 W, and filtering and drying to obtain the mineralizer. According to the method, industrial solid waste and waste materials are utilized, resource recycling is achieved, and the method is suitable for various engineering scenes such as industrial and civil buildings and roads and bridges and has environmental protection benefits and practical value.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cement mineralizer preparation, in particular to a preparation method and application of a low-carbon cement mineralizer. BACKGROUND

[0002] Cement is an important building material and plays a key role in global infrastructure construction. However, the traditional cement production process has high energy consumption and large carbon emissions, causing serious environmental burden. The high-temperature calcination link in the cement production process consumes a large amount of fossil energy, and the decomposition of limestone produces a large amount of carbon dioxide emissions. In order to reduce the carbon emissions of cement production and reduce the impact on the environment, the development of low-carbon cement production technology has become an important development direction of the industry.

[0003] Cement mineralizers can reduce the sintering temperature of cement clinker, promote the formation of minerals, and improve the quality and production efficiency of cement. However, the commonly used cement mineralizers have problems such as not being environmentally friendly and not being able to fully utilize industrial waste, which cannot meet the requirements of low-carbon and environmental protection. Therefore, it is urgent to develop a new type of low-carbon cement mineralizer and its preparation method to solve the problems in the prior art. SUMMARY

[0004] The present application aims to at least solve one of the above technical problems. The present application provides a preparation method and application of a low-carbon cement mineralizer, which comprises:

[0005] According to the weight ratio, 40-60 parts of industrial solid waste slag, 10-20 parts of waste glass, 5-15 parts of biomass charcoal, 10-30 parts of calcium-containing compounds, and 5-15 parts of magnesium-containing compounds are selected as raw materials; wherein the industrial solid waste slag is steel slag and / or phosphorus slag, the calcium-containing compound is at least one of calcium carbonate and calcium hydroxide, and the magnesium-containing compound is at least one of magnesium carbonate and magnesium oxide.

[0006] The use of industrial solid waste slag and waste glass realizes the resource utilization of waste, reducing the environmental pollution of solid waste; the addition of biomass charcoal not only helps to reduce carbon emissions in the cement production process, but also improves the performance of the mineralizer.

[0007] After mixing the above raw materials, 3-8% of a dispersing agent based on the total weight of the raw materials is added, the dispersing agent is sodium hexametaphosphate, and the grinding is carried out in a ball mill, the ball-to-material ratio is controlled to be (8-12) : 1, and the grinding time is 30-60 minutes to obtain a mixture. By adding a dispersing agent and controlling the grinding parameters, the raw materials can be fully mixed, the particles can be refined, and the reactivity of the raw materials can be improved, which is beneficial to the subsequent calcination and the formation of the performance of the mineralizer.

[0008] The mixture is placed in a rotary kiln with a temperature of 800-1000℃ for calcination for 1-2 hours, and then quickly cooled to room temperature at a cooling rate of 50-100℃ / min to obtain the calcined product. The lower calcination temperature significantly reduces energy consumption compared to traditional cement production, and the rapid cooling enables the calcined product to form a special microstructure, improving the activity of the mineralizer.

[0009] The calcined product is ultrasonically dispersed in deionized water at an ultrasonic frequency of 20-40kHz and a power of 200-500W for 15-30 minutes, filtered and dried to obtain the low-carbon cement mineralizer. Ultrasonic dispersion can further refine the particles, making the performance of the mineralizer more uniform and stable.

[0010] Further, the biomass char is prepared by pyrolysis of agricultural waste at 500-700℃ for 2-3 hours in an air-tight condition, and the agricultural waste is at least one of corn stalks and rice husks. The use of agricultural waste to prepare biomass char realizes the reuse of agricultural waste, and the biomass char has good adsorption and reactivity, which can improve the performance of the mineralizer.

[0011] Further, the proportion of particles with a particle size of less than 0.08mm in the ground mixture is more than 90%, ensuring sufficient mixing and reactivity of the raw materials.

[0012] Further, the drying temperature is 80-100℃ and the drying time is 2-4 hours, which ensures that the mineralizer is fully dried without affecting its performance.

[0013] Advantages

[0014] Low carbon and environmental protection: The low-carbon cement mineralizer preparation method of the present application uses industrial solid waste residues, waste glass and biomass char prepared from agricultural waste as raw materials, realizes the resource utilization of waste, reduces the dependence on natural resources; at the same time, the lower calcination temperature in the preparation process and the lower sintering temperature after adding the mineralizer in the cement production process significantly reduce the energy consumption and carbon dioxide emissions, which meets the development requirements of low carbon and environmental protection.

[0015] Excellent performance: By optimizing the preparation process and raw material formula, the low-carbon cement mineralizer prepared has a large specific surface area and a high content of active components, which can effectively reduce the sintering temperature of cement clinker, promote the formation of cement minerals, and improve the strength, durability and other properties of cement, meeting the needs of various construction projects.

[0016] Widely used: The cement prepared by the low-carbon cement mineralizer of the present application is suitable for industrial and civil construction engineering, road and bridge engineering, water conservancy and hydropower engineering, and underground pipe gallery engineering, etc., and has a wide application prospect. DETAILED DESCRIPTION

[0017] Example 1

[0018] Select steel slag 40 parts, waste glass 10 parts, biomass char prepared by pyrolysis of corn straw under air isolation condition at 500℃ for 2 hours 5 parts, calcium carbonate 10 parts, magnesium carbonate 5 parts as raw materials by weight ratio.

[0019] After mixing the above raw materials, 3% of sodium hexametaphosphate by total weight of raw materials is added as a dispersant, and grinding is carried out in a ball mill, the ball to material ratio is controlled to be 8:1, and the grinding time is 30 minutes, to obtain a mixture, and the detection shows that the proportion of particles with particle size less than 0.08mm in the mixture is more than 90%.

[0020] The mixture is placed in a rotary kiln at a temperature of 800℃ for calcination for 1 hour, and after calcination, it is rapidly cooled to room temperature at a cooling rate of 50℃ / min to obtain a calcined product.

[0021] The calcined product is ultrasonically dispersed in deionized water under the condition of ultrasonic frequency of 20kHz and power of 200W for 15 minutes, filtered and dried at 80℃ for 2 hours to prepare a low-carbon cement mineralizer. The detection shows that the specific surface area of the mineralizer is 350m 2 / g, and the active component content is 75%.

[0022] The prepared low-carbon cement mineralizer is added to the cement raw material composed of limestone, clay and iron powder at a proportion of 1% of the total weight of the cement raw material, and the cement raw material is ground to a specific surface area of 300m 2 / g, and then calcined at 1300℃ for 30 minutes to prepare cement. The test shows that the cement has good strength and durability performance when used in industrial building engineering.

[0023] Example 2

[0024] Select phosphorus slag 60 parts, waste glass 20 parts, biomass char prepared by pyrolysis of rice husk under air isolation condition at 700℃ for 3 hours 15 parts, calcium hydroxide 30 parts, magnesium oxide 15 parts as raw materials by weight ratio.

[0025] After mixing the above raw materials, 8% of sodium hexametaphosphate by total weight of raw materials is added as a dispersant, and grinding is carried out in a ball mill, the ball to material ratio is controlled to be 12:1, and the grinding time is 60 minutes, to obtain a mixture, and the detection shows that the proportion of particles with particle size less than 0.08mm in the mixture is 92%.

[0026] The mixture is placed in a rotary kiln at a temperature of 1000℃ for calcination for 2 hours, and after calcination, it is rapidly cooled to room temperature at a cooling rate of 100℃ / min to obtain a calcined product.

[0027] The calcined product is dispersed in deionized water under ultrasonic frequency of 40 kHz and power of 500 W for 30 minutes, filtered, and dried at 100 ℃ for 4 hours to obtain a low-carbon cement mineralizer. Test results show that the specific surface area of the mineralizer is 500 m 2 / kg, and the active component content is 78%.

[0028] The prepared low-carbon cement mineralizer is added to cement raw materials composed of limestone, clay, and iron powder at a proportion of 5% of the total weight of the cement raw materials, and the cement raw materials are ground to a specific surface area of 350 m 2 / kg, and then calcined at 1450 ℃ for 60 minutes to obtain cement. Test results show that the cement has excellent properties such as flexural strength and wear resistance when used in road and bridge engineering.

[0029] Example 3

[0030] Steel slag and phosphorus slag are selected at a weight ratio of 30:30, waste glass is 15 parts, biomass charcoal prepared by mixing corn straw and rice husk at a ratio of 1:1 under air isolation conditions at 600 ℃ for 2.5 hours is 10 parts, calcium carbonate and calcium hydroxide are each 15 parts, and magnesium carbonate and magnesium oxide are each 10 parts as raw materials.

[0031] The above raw materials are mixed, and 5% of the total weight of the raw materials is added as a dispersant. The mixture is ground in a ball mill, the ball-to-material ratio is controlled to be 10:1, and the grinding time is 45 minutes to obtain a mixture. Test results show that the proportion of particles with a particle size of less than 0.08 mm in the mixture reaches 91%.

[0032] The mixture is placed in a rotary kiln at a temperature of 900 ℃ and calcined for 1.5 hours. After calcination, it is rapidly cooled to room temperature at a cooling rate of 75 ℃ / min to obtain a calcined product.

[0033] The calcined product is dispersed in deionized water under ultrasonic frequency of 30 kHz and power of 350 W for 20 minutes, filtered, and dried at 90 ℃ for 3 hours to obtain a low-carbon cement mineralizer. Test results show that the specific surface area of the mineralizer is 420 m 2 / kg, and the active component content is 76%.

[0034] The prepared low-carbon cement mineralizer is added to cement raw materials composed of limestone, clay, and iron powder at a proportion of 3% of the total weight of the cement raw materials, and the cement raw materials are ground to a specific surface area of 320 m 2 / kg, and then calcined at 1380 ℃ for 45 minutes to obtain cement. Test results show that the cement has good properties such as impermeability and corrosion resistance when used in water conservancy and hydropower engineering.

[0035] The experimental data are as follows

[0036] Table 1 Raw material ratio of low-carbon cement mineralizer

[0037]

[0038]

[0039] Table 2 Performance parameters of low-carbon cement mineralizer

[0040]

[0041] Table 3 Cement production process parameters

[0042]

[0043]

[0044] Table 4 Cement performance test results

[0045]

[0046] The above examples are only used to illustrate the technical solutions of the present application, rather than limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing a low-carbon cement mineralizer, characterized in that, Includes the following steps: Select 40-60 parts by weight of industrial solid waste residue, 10-20 parts of waste glass, 5-15 parts of biochar, 10-30 parts of calcium-containing compounds, and 5-15 parts of magnesium-containing compounds as raw materials. After mixing the above raw materials, add a dispersant accounting for 3-8% of the total weight of the raw materials, and grind them in a ball mill, controlling the ball-to-material ratio to be 8-12:1, and the grinding time to be 30-60 minutes to obtain a mixture. The mixture is placed in a rotary kiln at a temperature of 800-1000℃ and calcined for 1-2 hours. After calcination, it is rapidly cooled to room temperature at a cooling rate of 50-100℃ / min to obtain the calcined product. The calcined product is ultrasonically dispersed in deionized water for 15-30 minutes at an ultrasonic frequency of 20-40kHz and a power of 200-500W, then filtered and dried to obtain the low-carbon cement mineralizer.

2. The method for preparing the low-carbon cement mineralizer according to claim 1, characterized in that, The industrial solid waste residue is at least one of steel slag and phosphorus slag, the calcium-containing compound is at least one of calcium carbonate and calcium hydroxide, and the magnesium-containing compound is at least one of magnesium carbonate and magnesium oxide.

3. The method for preparing the low-carbon cement mineralizer according to claim 1, characterized in that, The dispersant is sodium hexametaphosphate.

4. The method for preparing the low-carbon cement mineralizer according to claim 1, characterized in that, The biochar is produced by pyrolyzing agricultural waste at 500-700℃ for 2-3 hours in the absence of air.

5. The method for preparing the low-carbon cement mineralizer according to claim 4, characterized in that, The agricultural waste is at least one of corn stalks and rice husks.

6. The method for preparing the low-carbon cement mineralizer according to claim 1, characterized in that, The particles with a diameter of less than 0.08 mm account for no less than 90% of the ground mixture.

7. The method for preparing the low-carbon cement mineralizer according to claim 1, characterized in that, The drying temperature is 80-100℃, and the drying time is 2-4 hours.

8. A low-carbon cement mineralizer prepared by the preparation method according to any one of claims 1-7, characterized in that, The specific surface area of ​​the low-carbon cement mineralizer is 350-500 m². 2 / kg, with an active ingredient content of not less than 75%.

9. The application of the low-carbon cement mineralizer according to claim 8 in cement production, characterized in that, The low-carbon cement mineralizer is added to the cement raw materials at a ratio of 1-5% of the total weight of the cement raw materials, and cement is obtained through grinding and calcination processes; the cement is used in industrial and civil building projects, road and bridge projects, water conservancy and hydropower projects, and underground pipe gallery projects.

10. The application of the low-carbon cement mineralizer according to claim 9 in cement production, characterized in that, The cement raw materials include limestone, clay, and iron powder, and the specific surface area of ​​the ground cement raw materials is 300-350 m². 2 / kg, wherein the calcination temperature is 1300-1450℃ and the calcination time is 30-60 minutes.

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