Composite activator and application thereof

Abstract

The invention provides a composite exciting agent and application thereof, and relates to the technical field of exciting agents, and the composite exciting agent comprises an alkaline exciting agent, a calcium source exciting agent and an auxiliary exciting component. Industrial solid waste materials such as the slag, the fly ash and the steel slag can work cooperatively in the same system, the gelling performance, the mechanical strength and the durability of the material are remarkably improved, and the purposes of solid waste resource utilization and low-carbon environmental protection are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of stimulants, in particular to a composite stimulant and application thereof. Background Art

[0002] With the acceleration of industrialization, the output of industrial wastes such as slag, fly ash, steel slag, tailings powder, stone powder, phosphogypsum and papermaking mud continues to increase. These wastes not only occupy a large amount of land resources, but also may pollute the environment. The traditional cement production process is energy-intensive and has high carbon emissions. Therefore, the use of these industrial solid wastes to prepare low-carbon cementitious materials has become a research hotspot in the field of building materials.

[0003] At present, a single alkali activation system (such as NaOH, Na2SiO3, etc.) has been widely used in the process of industrial solid waste activation, but a single activator is difficult to fully exert the potential activity of different solid waste materials, resulting in limited material performance. Therefore, designing a composite activation system that allows different types of industrial solid waste to work together in the same system to maximize their gelation potential has become the key to solving this problem. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention proposes a composite activator and application thereof.

[0005] The invention provides a composite stimulant, which comprises an alkaline stimulant, a calcium source stimulant and an auxiliary stimulant component.

[0006] Preferably, the alkaline activator is at least one of sodium silicate, sodium hydroxide and potassium hydroxide to provide a high pH environment and accelerate the dissolution reaction of active components in the solid waste material.

[0007] Preferably, the calcium source activator is at least one of calcium hydroxide and calcium oxide to supplement calcium ions in the system, promote the formation of CSH gel, and enhance the early strength of the material.

[0008] Preferably, the auxiliary excitation component is at least one of activated alumina, silica fume and ceramic powder to further enhance the reaction activity of the system and promote the formation of CSH and NASH gel.

[0009] The present invention also provides application of the composite stimulant in stimulating active components in industrial solid waste.

[0010] Preferably, the industrial solid waste includes slag, fly ash, steel slag, tailings powder and stone powder. Among them, the main components of slag are SiO2, CaO and Al2O3, which have high potential activity, but need to be fully released through alkali excitation. Fly ash contains a large amount of SiO2 and Al2O3, which can form NASH gel through alkali excitation, thereby enhancing the long-term strength and durability of the material. 3 Steel slag is rich in CaO and Fe2O3, which can provide a calcium source and promote the formation of CSH gel. At the same time, some of its components can also participate in the excitation reaction. There are many inert components in solid waste materials such as tailings powder and stone powder, but under the synergistic effect of the composite activator, they can be partially activated to improve the comprehensive performance of the material.

[0011] Preferably, the weight of the composite activator accounts for 5-10% of the total weight of the material.

[0012] The composite activator of the present invention optimizes the reaction conditions of different solid waste materials, enhances the dissolution of active components such as silicon, aluminum, and calcium in the solid waste materials, and promotes the generation of more CSH (calcium silicate hydrate) and NASH (sodium aluminum silicate hydrate) gels, thereby stimulating the active components in industrial solid wastes such as slag, fly ash, steel slag, and tailings powder, maximizing the potential gelling properties of various solid wastes, and improving the mechanical properties, crack resistance, and durability of the materials, thereby preparing high-performance, low-carbon gelling materials.

[0013] The present invention achieves effective stimulation of industrial solid waste materials through the following physical and chemical mechanisms: (1) Synergistic excitation effect: A single alkaline excitation agent (such as Na2SiO3 or NaOH) can only excite some active components in slag, fly ash or steel slag. The composite excitation system, by introducing a variety of alkaline excitation agents and auxiliary components, can work synergistically to accelerate the dissolution and reaction of mineral components such as silicates and aluminates, forming more CSH and NASH gels, and significantly improving the mechanical properties and durability of the material.

[0014] (2) Complementarity of heterogeneous components: The components of industrial solid waste materials such as slag, fly ash and steel slag are different and complementary. In an alkaline environment, SiO2 in slag reacts with Al2O3 in fly ash to form calcium aluminum silicate gel. These gelled products are further increased under the action of composite activators, improving the bonding strength and crack resistance of the material.

[0015] (3) Advantages of composite alkali activation: Na2SiO3 provides active silicate components, which can combine with calcium ions provided by Ca(OH)2 to quickly form CSH gel, significantly enhancing the early strength of the material. The highly alkaline environment of NaOH or KOH can accelerate the dissolution process of solid waste materials and promote the generation of more CSH and NASH. In addition, auxiliary components such as active Al2O3 and silica fume further optimize the microstructure of the material through micro-filling and interfacial reaction, reduce porosity, and improve the density and durability of the material. Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes a composite activator, which can maximize the activation of active components in industrial solid wastes such as slag, fly ash, and steel slag by combining activators such as Na2SiO3, Ca(OH)2, and NaOH, and significantly improve the mechanical properties and gelling ability of the materials. The components in different solid waste materials undergo complementary reactions under the composite activation system to generate more gelling products, optimizing the mechanical properties and durability of the materials. By introducing auxiliary components such as active Al2O3 and silica fume, the activity of solid waste-based materials can be further enhanced, reducing dependence on traditional activators (such as cement), reducing carbon emissions, and achieving the goal of low-carbon and environmental protection. DETAILED DESCRIPTION

[0016] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0017] Embodiment 1: A composite activator comprises an alkaline activator, a calcium source activator and an auxiliary activating component. The alkaline activator is sodium silicate. The calcium source activator is calcium hydroxide. The auxiliary activating component is activated alumina.

[0018] Take 50% slag, 30% fly ash and 20% steel slag and mix them evenly, add the composite activator, and add appropriate amount of water and stir to form a gelled slurry. The slurry solidifies at room temperature. The compressive strength is 40MPa after 7 days and 65MPa after 28 days, and it shows excellent early strength and long-term durability.

[0019] Embodiment 2: A composite activator comprises an alkaline activator, a calcium source activator and an auxiliary activating component. The alkaline activator is sodium hydroxide. The calcium source activator is calcium oxide. The auxiliary activating component is silica fume.

[0020] Take 60% slag, 20% tailings powder and 20% stone powder and mix them evenly, add the composite activator, and add appropriate amount of water and stir to form a gelled slurry. The slurry solidifies at room temperature. The compressive strength is 38MPa after 7 days and 60MPa after 28 days. The crack resistance and durability of the material are also improved.

[0021] Embodiment 3: A composite activator comprises an alkaline activator, a calcium source activator and an auxiliary activating component. The alkaline activator is potassium hydroxide. The calcium source activator is calcium hydroxide. The auxiliary activating component is ceramic powder.

[0022] Take 60% slag, 30% steel slag and 10% stone powder and mix them evenly, add the composite activator, and add appropriate amount of water and stir to form a gelled slurry. The slurry solidifies at room temperature. The compressive strength is 42MPa after 7 days and 68MPa after 28 days. The crack resistance and durability of the material are also improved.

[0023] In summary, the composite activator of the present invention has excellent mechanical properties and durability, while reducing the dependence on traditional cement, and can be used for the preparation of building structural materials, meeting the requirements of green buildings. It also has good compression resistance, crack resistance and durability, and is suitable for road base materials. The early strength and long-term performance of the material are both excellent, and it can be used to produce prefabricated panels, bricks and other building components.

[0024] The above are only implementation modes of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent schemes made using the contents of the present invention specification, directly or indirectly applied in other related technical fields, are also within the patent protection scope of the present invention.

Claims

1. A composite activator, characterized in that: It includes an alkaline stimulator, a calcium source stimulator and an auxiliary stimulator component.

2. The composite activator according to claim 1, characterized in that The alkaline activator is at least one of sodium silicate, sodium hydroxide and potassium hydroxide.

3. The composite activator according to claim 1, characterized in that The calcium source activator is at least one of calcium hydroxide and calcium oxide.

4. The composite activator according to claim 1, characterized in that The auxiliary excitation component is at least one of activated alumina, silica fume and ceramic powder.

5. Use of the composite stimulant as described in any one of claims 1 to 4 in stimulating active components in industrial solid waste.

6. The use according to claim 5, characterized in that The industrial solid waste includes slag, fly ash, steel slag, tailings powder and stone powder.

7. The use according to claim 5, characterized in that The weight of the composite activator accounts for 5-10% of the total weight of the material.