A full-solid-waste self-exciting concrete and a preparation method and application thereof

Abstract

This invention relates to the field of building materials technology, specifically to a self-excited concrete made entirely from solid waste, its preparation method, and its application. The raw material components of the self-excited concrete include recycled coarse aggregate, iron tailings sand, activated coal gangue powder, mineral powder, desulfurization ash, alkali activator, water-reducing agent, sludge suppressant, and water; wherein the sludge suppressant comprises fatty alcohol, polyoxyethylene ether, and hexadecylamine. The sludge suppressant can stably adsorb the fine clay particles in the iron tailings sand, occupying adsorption sites on the surface of the fine clay particles, thereby preventing the adsorption of the water-reducing agent by the fine clay particles and improving the fluidity of the concrete slurry. The raw materials used in this invention are simple, readily available, and inexpensive, and the synergistic effect of each component effectively improves the fluidity and mechanical properties of the concrete. This invention effectively solves the problems of high energy consumption, high cost, low efficiency, and complex processing procedures caused by the lack of water solubility of the treatment materials used in existing tailings desludge removal technologies.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a self-excited concrete made entirely from solid waste, its preparation method, and its application. Background Technology

[0002] All-solid-waste concrete refers to concrete made entirely from solid waste materials, which mainly include granulated blast furnace slag, steel slag, red mud, waste gypsum, and tailings sand. Tailings sand is solid waste discharged from mines after grinding ores to extract valuable elements. Currently, there are reports that using tailings sand as aggregate in all-solid-waste concrete can effectively improve its strength. However, using tailings sand as aggregate requires pretreatment. While crushing, screening, and washing can remove most of the mud and harmful ions adhering to the tailings sand, some fine mud particles cannot be completely removed. These fine mud particles adhere to the aggregate surface, preferentially adsorbing water-reducing agents and requiring high water content. During the preparation of all-solid-waste concrete, they absorb water, reducing the fluidity of the concrete slurry, increasing its viscosity, and affecting the workability and mechanical properties of the concrete. Therefore, how to remove fine mud particles from tailings sand has become a major challenge for its reuse.

[0003] Traditional tailings sand desliming technologies mainly involve grading or thickening, but these technologies are energy-intensive, costly, and inefficient. In recent years, with the development of flocculation theory, flocculants suitable for tailings sand have been developed, such as polyacrylamide, sodium hexametaphosphate, or fatty acid salts. Adding flocculants to tailings sand can promote the aggregation of mud adhering to the tailings sand into flocs. However, these flocculants are usually not water-soluble and require subsequent rinsing with large amounts of water for removal, making the treatment process complex. Therefore, developing a simple, all-solid-waste concrete that can suppress the impact of fine mud particles in aggregates on concrete has significant practical implications for the building materials field. Summary of the Invention

[0004] To address the problems of high energy consumption, high cost, low efficiency, and complex processing procedures caused by the lack of water solubility in existing tailings desliming technologies, this invention provides a self-excited concrete made entirely from solid waste, its preparation method, and its application. This invention uses fatty alcohol, polyoxyethylene ether, and hexadecylamine as raw materials to prepare a mud inhibitor. This mud inhibitor can stably adsorb fine clay particles from iron tailings sand through positive and negative charge attraction, occupying adsorption sites on the surface of the fine clay particles. This prevents the fine clay particles from adsorbing water-reducing agents, improves the fluidity of the concrete slurry, and reduces its viscosity. Furthermore, the fine clay particles adsorbed by the mud inhibitor can also act as micro-fillers in the concrete slurry, improving the mechanical properties of the self-excited concrete made entirely from solid waste.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] The first aspect of this invention provides a self-activated concrete made entirely from solid waste, comprising the following raw material components in parts by weight: 900-1000 parts recycled coarse aggregate, 750-800 parts iron tailings sand, 80-120 parts activated coal gangue powder, 160-240 parts mineral powder, 190-230 parts desulfurization ash, 85-105 parts alkali activator, 14-16 parts water-reducing agent, 17-20 parts mud-suppressing agent, and 190-210 parts water;

[0007] The raw material components of the mud suppressant include C 12 -C 18 Fatty alcohols, polyoxyethylene ethers, and hexadecylamine.

[0008] Compared to existing technologies, this invention uses C 12 -C 18 A mud-suppressing agent was prepared using fatty alcohols, polyoxyethylene ethers, and hexadecylamine as main raw materials. This agent can inhibit the adsorption of water-reducing agents by fine clay particles in aggregates. Among them, C 12 -C 18 The fatty alcohols are not only rich in hydroxyl groups but also possess hydrophobic carbon chains, enabling them to form thin films at the water / oil interface. Polyoxyethylene ethers, containing long chains and ether bonds, exhibit excellent emulsifying and dispersing properties. The hydrophobic ends of their long chains interact with the hydrophobic carbon chains of the fatty alcohols, while the hydrophilic ends bind with water molecules, contributing to a stable dispersion system. Hexadecylamine molecules form hydrogen bonds with the hydroxyl groups of the fatty alcohols and activate with the polyoxyethylene ethers, forming a stable adsorption layer structure. More importantly, the positively charged portion of the hexadecylamine molecule attracts the negatively charged surface of the clay powder, occupying adsorption sites on the clay powder surface. Combined with the effects of the fatty alcohols and polyoxyethylene ethers, this achieves strong and stable adsorption of the clay powder, thus reducing the adsorption of water-reducing agents by the clay powder, improving the fluidity of the concrete slurry, and reducing its viscosity. Simultaneously, the clay powder adsorbed by the clay inhibitor acts as a micro-filler in the concrete slurry, thereby improving the mechanical properties of the self-excited all-solid-waste concrete.

[0009] Furthermore, this invention uses activated coal gangue powder, mineral powder, and desulfurization ash as active components, which can reduce the sensitivity of water-reducing agents to fine clay powder and improve the workability of concrete. Recycled coarse aggregate and iron tailings sand are used as aggregates, achieving complete solid waste replacement of aggregates and saving on concrete preparation costs. This invention utilizes the synergistic effect of its components to not only successfully inhibit the adsorption of water-reducing agents by fine clay powder but also effectively improve the mechanical properties of the self-excited concrete made entirely from solid waste. The raw materials used in this invention are simple, readily available, and inexpensive, providing a new approach to the preparation of all-solid-waste concrete and the reuse of solid waste materials.

[0010] Preferably, the C 12 -C 18 The fatty alcohol is any one of dodecyl alcohol, hexadecyl alcohol, or octadecyl alcohol.

[0011] Preferably, the method for preparing the mud suppressant includes the following steps:

[0012] Step a: Dissolve fatty alcohol, polyoxyethylene ether and strong alkali in deionized water and carry out hydrothermal reaction at 90℃-95℃ to obtain the first mixture;

[0013] Step b: Mix the first mixture with the metal catalyst evenly and carry out the activation reaction at 200℃-220℃ to obtain the second mixture;

[0014] Step c: Add a hexadecylamine alcohol solution to the second mixture and carry out a hydrothermal reaction at 96℃-98℃ under an inert atmosphere to obtain a mud suppressant.

[0015] More preferably, in step a, the mass ratio of the fatty alcohol, polyoxyethylene ether, and strong alkali is 1:3:0.2-1.2:4:0.4.

[0016] More preferably, the strong base is sodium hydroxide or potassium hydroxide.

[0017] More preferably, in step a, the mass-to-volume ratio of the fatty alcohol and deionized water is 1g:3mL-1g:4mL.

[0018] More preferably, in step a, the hydrothermal reaction time is 40 min to 60 min.

[0019] More preferably, in step b, the metal catalyst is an iron-based catalyst or a cobalt-based catalyst.

[0020] More preferably, in step b, the mass ratio of the first mixture to the metal catalyst is 1:0.01-1:0.03.

[0021] More preferably, in step b, the holding time for the activation reaction is 2.5h-3.5h.

[0022] More preferably, in step c, the hexadecylamine alcohol solution contains 25%-35% hexadecylamine by mass; and the solvent for the hexadecylamine alcohol solution is anhydrous ethanol.

[0023] More preferably, in step c, the mass ratio of the second mixture to the alcohol solution of hexadecylamine is 2:1 to 2.2:1.

[0024] More preferably, in step c, the hydrothermal reaction time is 1.5h-2.5h.

[0025] Preferably, the method for preparing the activated coal gangue powder includes the following steps: calcining the coal gangue powder at 700℃-750℃ and grinding it to obtain the activated coal gangue powder.

[0026] Further preferably, the temperature is increased to 700℃-750℃ at a heating rate of 10℃ / min-15℃ / min.

[0027] More preferably, the calcination time is 3-5 hours.

[0028] More preferably, the particle size of the activated coal gangue powder is 10μm-50μm.

[0029] Preferably, the alkaline activator is sodium silicate or slaked lime.

[0030] Preferably, the water-reducing agent is a polycarboxylate water-reducing agent.

[0031] Preferably, the mineral powder is of grade S95 or S105.

[0032] Preferably, the iron tailings sand has a particle size of 0.1mm-4.25mm.

[0033] Preferably, the particle size of the recycled coarse aggregate is 5mm-16mm.

[0034] Preferably, the particle size of the desulfurization ash is 10μm-75μm.

[0035] A second aspect of this invention provides a method for preparing self-excited concrete made entirely from solid waste, comprising the following steps:

[0036] Step 1: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix;

[0037] Step 2: Add water-reducing agent, water, alkali activator and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold, and cure to obtain all-solid waste self-excited concrete.

[0038] Preferably, the curing temperature is 28℃-32℃ and the curing humidity is 80%-90%.

[0039] The third aspect of this invention provides the application of the self-excited concrete made from all solid waste, or the self-excited concrete made from all solid waste prepared by the method described above, in the field of building materials.

[0040] In summary, this invention adopts C12 -C 18 A mud-suppressing agent was prepared using fatty alcohols, polyoxyethylene ethers, and hexadecylamine as raw materials. This agent can stably adsorb the fine clay particles from aggregates, occupying adsorption sites on the surface of the clay particles, thereby preventing the adsorption of water-reducing agents by the clay particles, improving the fluidity of the concrete slurry, and reducing its viscosity. Furthermore, this invention utilizes the synergistic effect of its components to effectively improve the mechanical properties of the self-excited concrete made entirely from solid waste. The raw materials used in this invention are simple, readily available, and inexpensive, providing a new approach for the preparation of all-solid-waste concrete and the reuse of solid waste materials. This invention effectively solves the problems of high energy consumption, high cost, low efficiency, and complex processing procedures caused by the lack of water solubility in existing tailings desliming technologies. Detailed Implementation

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] Example 1

[0043] This embodiment provides a self-excited concrete made entirely from solid waste, specifically including the following:

[0044] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g desulfurization ash, 100g sodium silicate, 15g polycarboxylate superplasticizer, 19g sludge suppressant, and 200g water.

[0045] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0046] Step 1: Dissolve 10g cetyl alcohol, 40g polyoxyethylene ether and 3g sodium hydroxide in 35mL of deionized water and carry out a hydrothermal reaction at 94℃ for 40min to obtain the first mixture;

[0047] Step 2: Mix the first mixture with 1g of iron-based catalyst evenly, and carry out the activation reaction at 210℃ to obtain the second mixture;

[0048] Step 3: Add 35g of 30wt% hexadecylamine ethanol solution to the second mixture, and carry out a hydrothermal reaction at 97°C for 2 hours under an inert atmosphere to obtain a mud suppressant;

[0049] Step 4: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix;

[0050] Step 5: Add polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0051] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0052] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0053] Example 2

[0054] This embodiment provides a self-excited concrete made entirely from solid waste, specifically including the following:

[0055] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 1000g recycled coarse aggregate, 780g iron tailings sand, 110g activated coal gangue powder, 180g S105 grade mineral powder, 220g desulfurization ash, 90g quicklime, 15g polycarboxylate superplasticizer, 18g mud suppressant, and 200g water.

[0056] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0057] Step 1: Dissolve 10g octadecyl alcohol, 40g polyoxyethylene ether and 3g sodium hydroxide in 35mL deionized water and carry out hydrothermal reaction at 95℃ for 40min to obtain the first mixture;

[0058] Step 2: Mix the first mixture with 1g of cobalt-based catalyst evenly, and carry out the activation reaction at 210°C to obtain the second mixture;

[0059] Step 3: Add 35g of 30wt% hexadecylamine ethanol solution to the second mixture, and carry out a hydrothermal reaction at 97°C for 2 hours under an inert atmosphere to obtain a mud suppressant;

[0060] Step 4: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S105 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mixture;

[0061] Step 5: Add polycarboxylate superplasticizer, water, quicklime and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0062] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 730℃ at a heating rate of 10℃ / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0063] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0064] Example 3

[0065] This embodiment provides a self-excited concrete made entirely from solid waste, specifically including the following:

[0066] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g desulfurization ash, 100g quicklime, 15g polycarboxylate superplasticizer, 19g mud suppressant, and 200g water.

[0067] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0068] Step 1: Dissolve 10g dodecanol, 40g polyoxyethylene ether and 3g sodium hydroxide in 35mL of deionized water and carry out a hydrothermal reaction at 94℃ for 40min to obtain the first mixture;

[0069] Step 2: Mix the first mixture with 1g of iron-based catalyst evenly, and carry out the activation reaction at 210℃ to obtain the second mixture;

[0070] Step 3: Add 35g of 30wt% hexadecylamine ethanol solution to the second mixture, and carry out a hydrothermal reaction at 97°C for 2 hours under an inert atmosphere to obtain a mud suppressant;

[0071] Step 4: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix;

[0072] Step 5: Add polycarboxylate superplasticizer, water, quicklime and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0073] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 750°C at a heating rate of 15°C / min for 3 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 50μm.

[0074] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0075] Comparative Example 1

[0076] This comparative example provides a self-excited concrete made entirely from solid waste, which differs from Example 1 in that the sludge suppressant does not contain polyoxyethylene ether, specifically including the following:

[0077] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g desulfurization ash, 100g sodium silicate, 15g polycarboxylate superplasticizer, 19g sludge suppressant, and 200g water.

[0078] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0079] Step 1: Dissolve 10g cetyl alcohol and 3g sodium hydroxide in 35mL of deionized water and carry out a hydrothermal reaction at 94℃ for 40min to obtain the first mixture;

[0080] Step 2: Mix the first mixture with 1g of iron-based catalyst evenly, and carry out the activation reaction at 210℃ to obtain the second mixture;

[0081] Step 3: Add 35g of 30wt% hexadecylamine ethanol solution to the second mixture, and carry out a hydrothermal reaction at 97°C for 2 hours under an inert atmosphere to obtain a mud suppressant;

[0082] Step 4: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mixture;

[0083] Step 5: Add polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0084] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0085] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0086] Comparative Example 2

[0087] This comparative example provides a self-excited concrete made entirely from solid waste. The difference from Example 1 is that the sludge suppressant is replaced with an equal amount of polyacrylamide, specifically including the following:

[0088] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g desulfurization ash, 100g sodium silicate, 15g polycarboxylate superplasticizer, 19g polyacrylamide, and 200g water.

[0089] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0090] Step 1: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix;

[0091] Step 2: Add polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0092] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0093] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0094] Comparative Example 3

[0095] This comparative example provides a self-excited concrete made entirely from solid waste. The difference from Example 1 is that it omits the sludge suppressant. Specifically, it includes the following:

[0096] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g desulfurization ash, 100g sodium silicate, 15g polycarboxylate superplasticizer, 19g sludge suppressant, and 200g water.

[0097] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0098] Step 1: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix;

[0099] Step 2: Add polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0100] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0101] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0102] Comparative Example 4

[0103] This comparative example provides a self-excited concrete made entirely from solid waste. The difference between this example and Comparative Example 3 is that the water-reducing agent is replaced with ZY-KN polycarboxylate-based high-performance water-reducing agent (anti-mud type water-reducing agent), specifically including the following:

[0104] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g desulfurization ash, 100g sodium silicate, 15g ZY-KN polycarboxylate-based high-performance water-reducing agent, and 200g water.

[0105] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0106] Step 1: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, desulfurization ash and iron tailings sand evenly to obtain dry mix;

[0107] Step 2: Add ZY-KN polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0108] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0109] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0110] Comparative Example 5

[0111] This comparative example provides a self-activated concrete made entirely from solid waste. The difference from Example 1 is that the activated coal gangue powder is replaced with an equal amount of fly ash, specifically including the following:

[0112] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g fly ash, 220g S95 grade mineral powder, 200g desulfurization ash, 100g sodium silicate, 15g polycarboxylate superplasticizer, 19g mud suppressant, and 200g water.

[0113] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0114] Step 1: Dissolve 10g cetyl alcohol, 40g polyoxyethylene ether and 3g sodium hydroxide in 35mL of deionized water and carry out a hydrothermal reaction at 94℃ for 40min to obtain the first mixture;

[0115] Step 2: Mix the first mixture with 1g of iron-based catalyst evenly, and carry out the activation reaction at 210℃ to obtain the second mixture;

[0116] Step 3: Add 35g of 30wt% hexadecylamine ethanol solution to the second mixture, and carry out a hydrothermal reaction at 97°C for 2 hours under an inert atmosphere to obtain a mud suppressant;

[0117] Step 4: Weigh each component raw material according to the design ratio, and mix the fly ash, S95 grade mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix;

[0118] Step 5: Add polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0119] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0120] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0121] Comparative Example 6

[0122] This comparative example provides a self-excited concrete made entirely from solid waste. The difference from Example 1 is that the desulfurization ash is replaced with an equal amount of phosphogypsum, specifically including the following:

[0123] The self-excited concrete made entirely from solid waste comprises the following raw material components in parts by weight: 950g recycled coarse aggregate, 800g iron tailings sand, 90g activated coal gangue powder, 220g S95 grade mineral powder, 200g phosphogypsum, 100g sodium silicate, 15g polycarboxylate superplasticizer, 19g sludge suppressant, and 200g water.

[0124] The preparation method of the self-excited concrete made entirely from solid waste includes the following steps:

[0125] Step 1: Dissolve 10g cetyl alcohol, 40g polyoxyethylene ether and 3g sodium hydroxide in 35mL of deionized water and carry out a hydrothermal reaction at 94℃ for 40min to obtain the first mixture;

[0126] Step 2: Mix the first mixture with 1g of iron-based catalyst evenly, and carry out the activation reaction at 210℃ to obtain the second mixture;

[0127] Step 3: Add 35g of 30wt% hexadecylamine ethanol solution to the second mixture, and carry out a hydrothermal reaction at 97°C for 2 hours under an inert atmosphere to obtain a mud suppressant;

[0128] Step 4: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, S95 grade mineral powder, phosphogypsum, iron tailings sand and mud suppressant evenly to obtain dry mixture;

[0129] Step 5: Add polycarboxylate superplasticizer, water, sodium silicate and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold it, and cure it at 30°C and 85% humidity for 28 days to obtain all-solid waste self-excited concrete.

[0130] The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder to 720°C at a heating rate of 12°C / min for 4 hours, and grinding it to obtain the activated coal gangue powder with a particle size of 40μm.

[0131] The iron tailings sand has a particle size of 1.5 mm; the recycled coarse aggregate has a particle size of 8 mm; and the desulfurization ash has a particle size of 50 μm.

[0132] To further demonstrate the technical effects of the present invention, relevant performance tests were conducted on the all-solid waste self-excited concretes obtained in Examples 1-3 and Comparative Examples 1-6. Specifically, the following were carried out: the slurry fluidity test was conducted in accordance with the standard GB / T 50080-2016 "Standard for Test Methods of Performance of Ordinary Concrete Mixtures", and the compressive strength test was conducted in accordance with the standard GB / T 50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete". The test results are shown in Table 1.

[0133] Table 1. Flow performance test results of the self-excited concrete obtained from Examples 1-3 and Comparative Examples 1-6.

[0134]

[0135] Table 2. Flow performance test results of the self-excited concrete obtained from Examples 1-3 and Comparative Examples 1-6.

[0136]

[0137] As can be seen from Tables 1 and 2, the self-excited concrete made entirely from solid waste described in Examples 1-3 of this invention exhibits superior fluidity and 28-day compressive strength. In particular, the self-excited concrete made entirely from solid waste described in Example 1 maintains a fluidity of 490 mm after 24 hours, with a 3-day compressive strength as high as 28.5 MPa, a 7-day compressive strength as high as 39.3 MPa, and a 28-day compressive strength as high as 55.2 MPa.

[0138] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A self-excited concrete made entirely from solid waste, characterized in that: The raw material components include the following parts by weight: 900-1000 parts recycled coarse aggregate, 750-800 parts iron tailings sand, 80-120 parts activated coal gangue powder, 160-240 parts mineral powder, 190-230 parts desulfurization ash, 85-105 parts alkali activator, 14-16 parts water-reducing agent, 17-20 parts mud suppressant, and 190-210 parts water; The raw material components of the mud suppressant include C 12 -C 18 Fatty alcohols, polyoxyethylene ethers, and hexadecylamine; The preparation method of the mud suppressant includes the following steps: Step a: Dissolve fatty alcohol, polyoxyethylene ether and strong alkali in deionized water and carry out hydrothermal reaction at 90℃-95℃ to obtain the first mixture; Step b: Mix the first mixture with the metal catalyst evenly and carry out the activation reaction at 200℃-220℃ to obtain the second mixture; Step c: Add a hexadecylamine alcohol solution to the second mixture and carry out a hydrothermal reaction at 96℃-98℃ under an inert atmosphere to obtain a mud suppressant.

2. The self-excited concrete made entirely from solid waste as described in claim 1, characterized in that: In step a, the mass ratio of the fatty alcohol, polyoxyethylene ether, and strong base is 1:4:0.3; and / or In step a, the mass-to-volume ratio of the fatty alcohol to deionized water is 1g:3mL-1g:4mL; and / or In step a, the hydrothermal reaction takes 40-60 minutes.

3. The self-excited concrete made entirely from solid waste as described in claim 1, characterized in that: In step b, the metal catalyst is an iron-based catalyst or a cobalt-based catalyst; and / or In step b, the mass ratio of the first mixture to the metal catalyst is 1:0.01-1:0.03; and / or In step b, the activation reaction takes 2.5 h to 3.5 h.

4. The self-excited concrete made entirely from solid waste as described in claim 1, characterized in that: In step c, the hexadecylamine alcohol solution contains 25%-35% hexadecylamine by mass; the solvent for the hexadecylamine alcohol solution is anhydrous ethanol; and / or In step c, the mass ratio of the second mixture to the alcoholic solution of hexadecylamine is 2:1 to 2.2:1; and / or In step c, the hydrothermal reaction takes 1.5h-2.5h.

5. The self-excited concrete made entirely from solid waste as described in claim 1, characterized in that: The preparation method of the activated coal gangue powder includes the following steps: calcining the coal gangue powder at 700℃-750℃ and grinding it to obtain the activated coal gangue powder.

6. The self-excited concrete made entirely from solid waste as described in claim 5, characterized in that: In the calcination process of coal gangue powder, the temperature is increased to 700℃-750℃ at a heating rate of 10℃ / min-15℃ / min; and / or The calcination time is 3-5 hours; and / or The activated coal gangue powder has a particle size of 10μm-50μm.

7. The self-excited concrete made entirely from solid waste as described in claim 1, characterized in that: The alkaline activator is sodium silicate or quicklime; and / or The water-reducing agent is a polycarboxylate water-reducing agent; and / or The mineral powder is S95 or S105 grade; and / or The iron tailings sand has a particle size of 0.1mm-4.25mm; and / or The recycled coarse aggregate has a particle size of 5mm-16mm; and / or The particle size of the desulfurization ash is 10μm-75μm.

8. A method for preparing self-excited concrete made entirely from solid waste as described in any one of claims 1-7, characterized in that: Includes the following steps: Step 1: Weigh each component raw material according to the design ratio, and mix the activated coal gangue powder, mineral powder, desulfurization ash, iron tailings sand and mud suppressant evenly to obtain dry mix; Step 2: Add water-reducing agent, water, alkali activator and recycled coarse aggregate to the dry mix in sequence, mix evenly to obtain slurry; mold the slurry, demold, and cure to obtain all-solid waste self-excited concrete.

9. The application of self-excited concrete made entirely from solid waste as described in any one of claims 1-7, or self-excited concrete made entirely from solid waste prepared by the method described in claim 8, in the field of building materials.

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