Artificial lightweight aggregate taking industrial waste alkali as alkali activator and preparation method of artificial lightweight aggregate

Abstract

The invention relates to the field of building materials, and discloses an artificial lightweight aggregate with industrial waste alkali as an alkali activator and a preparation method thereof.The artificial lightweight aggregate is prepared from, by weight, 30-40 parts of F-class fly ash, 30-40 parts of S95-grade mineral powder, 10-20 parts of zeolite powder, 5-15 parts of sodium silicate or potassium silicate, 5-10 parts of industrial waste alkali and 0-20 parts of water; the preparation method comprises the following steps: weighing the raw materials in proportion, mechanically stirring the raw materials for several stages, granulating the mixture in a rotary table or a cylindrical rotary drum, spraying water in an atomization manner until the particle diameter reaches 18-22 mm, and finally curing in a natural environment to prepare the lightweight aggregate. According to the invention, the resource utilization of the industrial waste alkali is realized, the dependence of natural aggregate is reduced, the preparation process is simple, the product performance is excellent, and the economic and environment-friendly benefits are remarkable.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, in particular to an artificial lightweight aggregate using industrial waste alkali as an alkali activator and a preparation method thereof. Background Art

[0002] With the rapid development of the construction industry, the demand for concrete, as a widely used building material, continues to increase. One of the main components of concrete is aggregate, and the mining of natural aggregates such as sand and gravel has reached the limit of resource carrying capacity. The large-scale mining of natural aggregates not only causes serious damage to the ecological environment, but also leads to more prominent resource shortage problems. In addition, the high-density characteristics of aggregates in concrete put forward higher requirements for the lightweight and energy-saving of modern buildings. Therefore, finding a new type of artificial aggregate that can replace natural aggregates and has lightweight characteristics has become an important research direction in the field of building materials.

[0003] On the other hand, a large amount of solid waste generated during industrial production, such as fly ash, blast furnace slag and industrial waste alkali, has not been effectively utilized for a long time, and is often treated by simple accumulation or landfill. These treatment methods not only consume a lot of land resources, but may also cause serious environmental pollution, such as soil salinization, water pollution and leakage of harmful substances. At the same time, the high cost of waste treatment has also brought economic burdens to enterprises and society.

[0004] In the prior art, attempts have been made to use industrial solid waste (such as fly ash and slag) to prepare building materials. However, these technical solutions are mostly based on chemical reagents or high-energy consumption processes, such as high-temperature firing or complex physical treatment processes. These methods often have problems such as complex processes, high energy consumption, and high costs. In addition, some technical solutions have limited utilization of industrial waste alkali, and have not yet fully utilized the potential of waste alkali liquid or waste alkali residue in stimulating the activity of other solid wastes.

[0005] Therefore, existing technologies are still unable to achieve efficient resource utilization of industrial waste alkali and other industrial solid wastes under low energy consumption conditions, while meeting the requirements of building materials for lightness and mechanical properties. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides an artificial lightweight aggregate using industrial waste alkali as an alkali activator and a preparation method thereof, which solves the problems in the prior art of low utilization rate of industrial waste alkali and other industrial solid wastes, shortage of natural aggregate resources, and complex preparation process and high cost of artificial lightweight aggregate.

[0007] To achieve the above object, the present invention is implemented by the following technical scheme: an artificial lightweight aggregate using industrial waste alkali as an alkali activator, comprising the following components by weight: 30-40 parts of Class F fly ash; 30-40 parts of S95 grade mineral powder; 10-20 parts of zeolite powder; 5-15 parts of sodium silicate or potassium silicate; 5-10 parts of industrial waste alkali; 0-20 parts of water.

[0008] Preferably, the industrial waste alkali is waste alkali liquid or waste alkali residue generated in the industrial production process, and the main components of the waste alkali include CaO and NaOH.

[0009] Preferably, the sodium silicate is liquid sodium silicate with a modulus of 2.20 to 2.50, and the potassium silicate is liquid sodium silicate with a density of 1.394 to 1.450 g / cm 3 Liquid potassium silicate.

[0010] Preferably, the particle size of the zeolite powder is 150-200 mesh, and the purity is greater than 95%.

[0011] Preferably, the particle size distribution of the artificial lightweight aggregate is: 0mm~5mm accounts for 3%~8%, 5mm~10mm accounts for 27%~35%, 10mm~16mm accounts for 40%~42%, 16mm~20mm accounts for 5%~19%, 20mm~25mm accounts for 9%~12%.

[0012] The present invention also provides a method for preparing artificial lightweight aggregate using industrial waste alkali as an alkali activator, comprising the following steps: S1. Weigh the raw materials according to the specified weight portions respectively; S2, mixing the raw materials and mechanically stirring; S3, placing the stirred mixture in a disc or cylindrical drum with the disc tilted at an angle of 45° and a rotation speed of 40 r / min, and spraying water evenly in the material in the form of atomization during the stirring process; S4. During the stirring process, observe the agglomeration of the particles. Stop stirring when more than 80% of the particles are agglomerated to 18mm to 22mm. S5. Take out the particles and cure them in a natural environment.

[0013] Preferably, the mechanical stirring is carried out in the following steps: Stir at a speed of 140±2r / min for 30±1s; Stir at a speed of 285±3r / min for 30±1 seconds; Stop stirring for 90 seconds, put down the mixing pot, and use a spatula to scrape the materials on the mixer into the pot; Stir at a speed of 285±3r / min for 60±1 seconds.

[0014] Preferably, the amount of water sprayed by atomization in the disc or cylindrical drum is 20%-26% of the weight of the mixed material.

[0015] Preferably, the temperature of the natural environment curing is 20°C-25°C, the humidity is 50%-70%, and the curing time is 7 days.

[0016] The present invention also provides an application of the artificial lightweight aggregate using industrial waste alkali as an alkali activator in preparing lightweight concrete or non-load-bearing structure building materials.

[0017] The present invention provides an artificial lightweight aggregate using industrial waste alkali as an alkali activator and a preparation method thereof. It has the following beneficial effects: 1. The present invention uses industrial waste alkali (including waste alkali liquid and waste alkali residue) as an alkali activator to directly activate the volcanic ash effect of F-class fly ash and S95-grade mineral powder, thereby converting waste into high-value-added building materials. This resource utilization method effectively reduces the accumulation and treatment costs of industrial waste alkali and the risk of environmental pollution, and provides a green solution for the harmless treatment and reuse of industrial waste.

[0018] 2. The artificial lightweight aggregate provided by the present invention is made of industrial solid waste (such as fly ash and mineral powder) and auxiliary materials, which completely replaces natural aggregate and solves the problem of shortage of natural sand and stone resources in the construction industry. By reducing the exploitation of natural resources, ecological damage and environmental pressure are reduced, which is in line with the concept of sustainable development.

[0019] 3. The present invention adopts the preparation process of mechanical stirring, rotary granulation and natural curing, which does not require high-temperature calcination or complex chemical reaction processes, greatly reducing the energy consumption in the production process. The natural curing process further reduces energy use and realizes low-energy consumption and high-efficiency production of artificial lightweight aggregate.

[0020] 4. The prepared artificial lightweight aggregate has excellent physical properties, reasonable particle size distribution, low bulk density, high cylinder pressure strength, moderate porosity, and fully meets the technical index requirements of concrete aggregate. The product has both lightness and strength, and is suitable for the preparation of lightweight concrete and can also be used as a building material for non-load-bearing structures, meeting the diverse engineering application needs.

[0021] 5. The present invention adds zeolite powder to give artificial lightweight aggregate good adsorption, which can fix heavy metal ions and other harmful components in industrial waste alkali, effectively reducing the environmental harm of waste alkali. The preparation process generates less solid waste and does not emit toxic by-products, which significantly improves the environmental friendliness of the production.

[0022] 6. The present invention uses low-cost industrial byproducts such as fly ash, mineral powder and industrial waste alkali as the main raw materials, avoiding the use of expensive chemical reagents and significantly reducing production costs. Compared with traditional natural aggregates or high-energy-consuming production methods, the artificial lightweight aggregate production of the present invention has higher economy and market competitiveness.

[0023] 7. The artificial lightweight aggregate of the present invention is not only suitable for lightweight concrete for ordinary construction, but also can be used for non-load-bearing structures such as roof insulation layer and partition wall filling materials, and has a wide market demand. Its high cost performance and environmental protection characteristics further enhance the competitiveness of the product, and it has good promotion value and industrialization prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the production process of artificial lightweight aggregate of the present invention; Figure 2 It is a schematic diagram of the artificial lightweight aggregate product of the present invention; Figure 3 is a SEM schematic diagram of Example 1 of the present invention; Figure 4 This is a SEM schematic diagram of Example 2 of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not 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.

[0026] Please see attached Figure 1 -Attached Figure 2 The present invention provides an artificial light aggregate using industrial waste alkali as an alkali activator. The artificial light aggregate formula specifically includes the following components: 30-40 parts of Class F fly ash, 30-40 parts of S95 grade mineral powder, 10-20 parts of zeolite powder, 5-15 parts of sodium silicate or potassium silicate, 5-10 parts of industrial waste alkali, and 0-20 parts of water. As an option, the main components of the industrial waste alkali include CaO and NaOH, which provide the necessary alkaline environment for the alkali-activated reaction in the material system, and can effectively activate the volcanic ash effect of fly ash and mineral powder.

[0027] Specifically, the F-type fly ash is selected from fly ash captured from coal-fired power plants, and its chemical composition mainly includes SiO 2 、Al 2 O 3 , Fe 2 O 3 In a possible implementation, the fly ash is preferably Class II fly ash, whose fineness and activity meet the requirements of the mixing reaction and can provide sufficient silicon and aluminum sources for the material system to react with the alkaline components to form a gel structure.

[0028] It should be noted that the S95 grade ore powder is slag powder produced in the blast furnace ironmaking process, and its main components include silicate and aluminosilicate. In some embodiments of the present invention, the S95 grade ore powder can significantly improve the strength and stability of the material through the action of an alkali activator. It is understandable that the fineness and activity of the ore powder are important factors in ensuring the strength and density of artificial lightweight aggregate.

[0029] Exemplarily, zeolite powder is added as a porous structure material in the present invention, mainly composed of aluminum silicate, with a particle size range of 150 mesh to 200 mesh and a purity greater than 95%. Specifically, the addition of zeolite powder can improve the porosity of lightweight aggregate and provide adsorption performance for the material system. It should be noted that zeolite powder can adsorb some heavy metal ions in industrial waste alkali during the reaction process, thereby improving the safety and environmental friendliness of lightweight aggregate.

[0030] In a possible implementation, sodium silicate or potassium silicate is added as an inorganic binder, wherein sodium silicate is in liquid form with a modulus of 2.20 to 2.50, and potassium silicate has a density of 1.394 to 1.450 g / cm³. These inorganic binders can improve the adhesion of the mixed system in an alkali-activated reaction and help the molding and densification of the material surface.

[0031] As an option, industrial waste alkali is the main source of the alkali activator, and waste alkali liquid or waste alkali residue can be selected. In the present invention, the main components of industrial waste alkali include CaO and NaOH, and their contents are in the range of 5 to 10 parts. By providing a sufficient amount of OH - Ions react with the active silicon and aluminum components in fly ash and mineral powder to form a gel phase. It should be noted that industrial waste alkali not only reduces production costs, but also realizes the resource utilization of industrial waste.

[0032] In this embodiment, water is mainly added as a reaction medium, and its amount is 0 to 20 parts. In some embodiments, water can be gradually added to the mixture by atomization spraying to ensure that the raw materials can be evenly mixed and avoid the phenomenon of local over-wetting or over-drying. It can be understood that the control of the amount of water directly affects the molding quality of lightweight aggregate and the subsequent reaction efficiency.

[0033] It should be noted that, in this embodiment, after the raw materials are mixed according to the above formula, the lightweight aggregate is prepared by mechanical stirring, rotary granulation and natural curing process, and its particle size distribution includes 0mm-5mm accounting for 3%-8%, 5mm-10mm accounting for 27%-35%, 10mm-16mm accounting for 40%-42%, 16mm-20mm accounting for 5%-19%, and 20mm-25mm accounting for 9%-12%. Exemplarily, this particle size distribution can meet the technical requirements of lightweight aggregate for concrete and ensure that the aggregate has good uniformity and mechanical properties in concrete.

[0034] It should be noted that the formula of the artificial lightweight aggregate of the present invention uses industrial waste alkali as an alkali activator through reasonable component selection and proportion, which not only realizes the resource utilization of waste alkali, but also significantly reduces the production cost. Specifically, the alkaline components of industrial waste alkali can effectively stimulate the potential activity of fly ash and mineral powder, and work together with sodium silicate or potassium silicate to generate stable silicate and aluminate gels, thereby giving the lightweight aggregate higher strength and lower density.

[0035] It should be further explained that the addition of zeolite powder improves the lightness and adsorption capacity of the aggregate, and at the same time provides a mechanism for fixing harmful ions in the waste alkali system, ensuring the environmental friendliness of the product. In the formula design, by controlling the weight of each component, the final prepared lightweight aggregate not only meets the performance requirements of lightweight aggregate for construction, but also can significantly reduce the environmental burden during the production process.

[0036] It can be understood that the lightweight aggregate formula and preparation method of the present invention provide a practical technical solution for solving the problem of industrial waste alkali treatment and the shortage of natural aggregate resources.

[0037] Correspondingly, the present invention also provides a method for preparing the above-mentioned artificial lightweight aggregate using industrial waste alkali as an alkali activator, comprising the following steps: raw material weighing, mechanical stirring, granulation and curing. It should be noted that the preparation method fully combines the alkaline characteristics of industrial waste alkali, and by accurately controlling the process parameters in each process step, the prepared artificial lightweight aggregate has excellent physical properties and environmental friendliness.

[0038] As an option, first, according to the above formula, Class F fly ash, S95 grade mineral powder, zeolite powder, sodium silicate or potassium silicate, industrial waste alkali and water are weighed in proportion. Specifically, the weighing accuracy of each raw material should be controlled within ±0.1g to ensure the accuracy of the proportion of each component. In some embodiments, the industrial waste alkali can be waste alkali liquid or waste alkali residue, the main components of which are CaO and NaOH, which stimulate the volcanic ash effect of fly ash and mineral powder by providing sufficient OH⁻ ions. It should be noted that water is gradually added as a reaction medium, which can not only improve the mixing uniformity, but also provide suitable humidity for subsequent granulation.

[0039] In one possible implementation, the weighed raw materials are added to the stirring pot in sequence and mechanically stirred. Exemplarily, the stirring speed and time are controlled in stages during the stirring process to ensure uniform mixing. First, stir at a low speed of 140±2r / min for 30±1 seconds to preliminarily mix the components to prevent particles from flying and ensure uniform distribution. Then stir at a high speed of 285±3r / min for 30±1 seconds to further promote uniform dispersion of the materials. After stopping stirring for 90 seconds, scrape the material on the inner wall of the mixer back into the stirring pot with a scraper to prevent waste of raw materials. Then stir at a high speed of 285±3r / min for 60±1 seconds again to fully contact the surface of fly ash and mineral powder with industrial waste alkali, sodium silicate or potassium silicate. It can be understood that through this stirring process, the components can be fully dispersed and form a uniform mixture.

[0040] It should be noted that after the mixture is stirred, it is placed on a disc or a cylindrical drum for granulation. The inclination angle of the drum is set to 45°, and the rotation speed is controlled at 40r / min to ensure that the mixture rolls evenly in the drum. In some embodiments, water is gradually added by atomization spraying, and the spraying amount is controlled to be 20%-26% of the weight of the mixture. Specifically, atomization spraying can ensure uniform distribution of water, prevent local over-wetting or over-drying, and help the formation and agglomeration of particles. As an option, during the granulation process, by adjusting the rotation speed and water volume, the agglomeration of the particles is gradually observed to ensure that the particle size of the particles meets the requirements.

[0041] In a possible implementation, during the mixing process, when the diameter of the particles reaches 18 mm to 22 mm, it indicates that most of the particles have formed a stable structure, and the mixing should be stopped and the particles should be taken out. It should be noted that by controlling the diameter range of the particles, it can be ensured that the particle size distribution of the lightweight aggregate meets the technical requirements of concrete aggregate.

[0042] After the granulation is completed, the formed particles are placed in a natural environment for curing. Specifically, the curing conditions are controlled at a temperature of 20°C to 25°C, a humidity of 50% to 70%, and a curing time of 7 days. During the curing process, CaO and NaOH in the industrial waste alkali react with the active silicon and aluminum components in the fly ash and mineral powder to form silicate and aluminate gelling substances, thereby significantly improving the strength and stability of the particles. It can be understood that natural environment curing can not only reduce energy consumption, but also make the chemical reaction inside the lightweight aggregate more sufficient, forming a uniform and dense internal structure.

[0043] As an option, the artificial lightweight aggregate finally prepared has excellent particle size distribution and physical properties. Exemplarily, the particle size distribution range of the lightweight aggregate includes: 0mm to 5mm accounts for 3%-8%, 5mm to 10mm accounts for 27%-35%, 10mm to 16mm accounts for 40%-42%, 16mm to 20mm accounts for 5%-19%, and 20mm to 25mm accounts for 9%-12%. Through the precise control of the above process parameters, it can be ensured that the particle size distribution of the lightweight aggregate meets the standard requirements of concrete aggregate for construction, and has both lightness and strength.

[0044] It should be noted that the preparation method of the present invention effectively realizes the resource utilization of fly ash and mineral powder by optimizing the parameters in each process step and combining the alkali excitation characteristics of industrial waste alkali. - Ions can stimulate the volcanic ash effect of fly ash and mineral powder, and work together with sodium silicate or potassium silicate to form dense silicate and aluminate structures. This process not only makes lightweight aggregates have excellent physical properties, but also significantly reduces the cost of stacking and processing industrial waste alkali, providing a practical technical approach for resource utilization.

[0045] It can be understood that the artificial lightweight aggregate prepared by the above preparation method not only meets the various performance index requirements of concrete aggregate, but also can significantly reduce carbon emissions and resource consumption in the production process, and has good economic and social benefits. Finally, the present invention provides an efficient, environmentally friendly and sustainable lightweight aggregate preparation method, which provides a new solution for the technical upgrading of the building materials field.

[0046] The artificial lightweight aggregate provided by the present invention can be widely used in the field of building materials, and is particularly suitable for preparing lightweight concrete and building materials for non-load-bearing structures. Specifically, the lightweight aggregate can play an important role in lightweight structures such as thermal insulation layers, roof fillings, and partition boards due to its low bulk density, excellent particle size distribution, and suitable cylinder compressive strength. As a green and environmentally friendly building material, the artificial lightweight aggregate of the present invention significantly reduces dependence on natural aggregate resources by resource-based utilization of industrial waste alkali and other industrial by-products, while meeting the needs of modern buildings for lightweight, energy-saving, and environmental protection, and has broad market prospects and application value.

[0047] In order to better understand the present invention, the present invention is described in detail below in conjunction with specific embodiments.

[0048] Embodiment 1: In this embodiment, the following raw materials are used to prepare artificial lightweight aggregate: Class F II fly ash: 35kg; S95 grade mineral powder: 35kg; Zeolite powder: 15kg; Sodium silicate (modulus 2.7): 10kg; Industrial waste alkali (waste alkali liquid): 5kg; Water: 10kg.

[0049] According to the preparation method of the above specific embodiment, mixing, stirring, granulation and curing are completed to obtain lightweight aggregate. After testing, the properties of the prepared lightweight aggregate are as follows: Particle size distribution (by mass): 0mm-5mm accounts for 8%, 5mm-10mm accounts for 35%, 10mm-16mm accounts for 40%, 16mm-20mm accounts for 5%, 20mm-25mm accounts for 12%; Cylinder pressure strength: 5.7MPa; Bulk density: 980kg / m 3 ; Apparent density: 1740kg / m 3 ; Void ratio: 44%.

[0050] like Figure 3 As shown in the figure, the internal structure of the lightweight aggregate is dense, mainly composed of cubic mineral structure, observed by scanning electron microscopy (SEM).

[0051] Embodiment 2: In this embodiment, the following raw materials are used to prepare artificial lightweight aggregate: Class F, Grade II fly ash: 30kg; S95 grade mineral powder: 30kg; Zeolite powder: 10kg; Sodium silicate (modulus 2.7): 7.5kg; Industrial waste alkali (waste alkali residue): 7.5kg; Water: 25kg.

[0052] According to the preparation method of the above specific embodiment, mixing, stirring, granulation and curing are completed to obtain lightweight aggregate. After testing, the properties of the prepared lightweight aggregate are as follows: Particle size distribution (by mass): 0mm-5mm accounts for 3%, 5mm-10mm accounts for 27%, 10mm-16mm accounts for 42%, 16mm-20mm accounts for 19%, and 20mm-25mm accounts for 9%; Cylinder pressure strength: 3.9MPa; Bulk density: 890kg / m 3 ; Apparent density: 1540kg / m 3 ; Void ratio: 42%.

[0053] like Figure 4 As shown in the figure, through scanning electron microscopy (SEM) observation, the internal structure of the lightweight aggregate is mainly composed of flake minerals, showing a high lightweight characteristic.

[0054] Embodiment 3: In this embodiment, the following raw materials are used to prepare artificial lightweight aggregate: Class F II fly ash: 38kg; S95 grade mineral powder: 32kg; Zeolite powder: 18kg; Sodium silicate (modulus 2.7): 10kg; Industrial waste alkali (waste alkali liquid): 6kg; Water: 12kg.

[0055] The process operation is completed according to the preparation method described in the specific implementation method to obtain lightweight aggregate. After testing, the properties of the lightweight aggregate are as follows: Particle size distribution (by mass): 0mm-5mm accounts for 6%, 5mm-10mm accounts for 32%, 10mm-16mm accounts for 42%, 16mm-20mm accounts for 10%, and 20mm-25mm accounts for 10%; Cylinder pressure strength: 5.5MPa; Bulk density: 970kg / m 3 ; Apparent density: 1720kg / m 3 ; Void ratio: 43%.

[0056] It can be understood that, in this embodiment, by slightly increasing the ratio of fly ash to zeolite powder, the internal structure of the lightweight aggregate maintains a relatively high density, while achieving a good balance between strength and lightness.

[0057] Embodiment 4: In this embodiment, the following raw materials are used to prepare artificial lightweight aggregate: Class F, Grade II fly ash: 28kg; S95 grade mineral powder: 35kg; Zeolite powder: 12kg; Sodium silicate (modulus 2.7): 8kg; Industrial waste alkali (waste alkali residue): 9kg; Water: 22kg.

[0058] The process operation is completed according to the preparation method described in the specific implementation method to obtain lightweight aggregate. After testing, the properties of the lightweight aggregate are as follows: Particle size distribution (by mass): 0mm-5mm accounts for 4%, 5mm-10mm accounts for 28%, 10mm-16mm accounts for 40%, 16mm-20mm accounts for 18%, and 20mm-25mm accounts for 10%; Cylinder pressure strength: 4.1MPa; Bulk density: 900kg / m 3 ; Apparent density: 1550kg / m 3 ; Void ratio: 42%.

[0059] It should be noted that in this embodiment, by increasing the proportion of industrial waste alkali (waste alkali residue) and appropriately increasing the amount of water, a relatively lightweight aggregate is obtained, and its cylinder compressive strength is suitable for the application scenario of non-load-bearing building materials.

[0060] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An artificial lightweight aggregate using industrial waste alkali as an alkali activator, characterized in that: The following components are included by weight: 30-40 parts of Class F fly ash; 30-40 parts of S95 grade mineral powder; 10-20 parts of zeolite powder; 5-15 parts of sodium silicate or potassium silicate; 5-10 parts of industrial waste alkali; 0-20 parts of water.

2. The artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 1 is characterized in that: The industrial waste alkali is waste alkali liquid or waste alkali residue generated in the industrial production process, and the main components of the waste alkali include CaO and NaOH.

3. The artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 1 is characterized in that: The sodium silicate is liquid sodium silicate with a modulus of 2.20 to 2.50, and the potassium silicate is liquid sodium silicate with a density of 1.394 to 1.450 g / cm 3 Liquid potassium silicate.

4. The artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 1 is characterized in that: The particle size of the zeolite powder is 150-200 meshes, and the purity is greater than 95%.

5. The artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 1 is characterized in that: The particle size distribution of the artificial lightweight aggregate is: 0mm~5mm accounts for 3%~8%, 5mm~10mm accounts for 27%~35%, 10mm~16mm accounts for 40%~42%, 16mm~20mm accounts for 5%~19%, 20mm~25mm accounts for 9%~12%.

6. A method for preparing artificial lightweight aggregate using industrial waste alkali as an alkali activator, preparing the artificial lightweight aggregate using industrial waste alkali as an alkali activator as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Weigh the raw materials according to the specified weight portions respectively; S2, mixing the raw materials and mechanically stirring; S3, placing the stirred mixture in a disc or cylindrical drum with the disc tilted at an angle of 45° and a rotation speed of 40 r / min, and spraying water evenly in the material in the form of atomization during the stirring process; S4. During the stirring process, observe the agglomeration of the particles. Stop stirring when more than 80% of the particles are agglomerated to 18mm to 22mm. S5. Take out the particles and cure them in a natural environment.

7. The method for preparing artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 6, characterized in that: The mechanical stirring is carried out in the following steps: Stir at a speed of 140±2r / min for 30±1s; Stir at a speed of 285±3r / min for 30±1 seconds; Stop stirring for 90 seconds, put down the mixing pot, and use a spatula to scrape the materials on the mixer into the pot; Stir at a speed of 285±3r / min for 60±1 seconds.

8. The method for preparing artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 6, characterized in that: The amount of water sprayed by atomization in the disc or cylindrical drum is 20%-26% of the weight of the mixed material.

9. The method for preparing artificial lightweight aggregate using industrial waste alkali as alkali activator according to claim 6, characterized in that: The temperature of the natural environment curing is 20°C-25°C, the humidity is 50%-70%, and the curing time is 7 days.

10. Use of the artificial lightweight aggregate using industrial waste alkali as an alkali activator as claimed in any one of claims 1 to 5 in the preparation of lightweight concrete or non-load-bearing structure building materials.

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