Waste polishing liquid acid-activated geopolymer regenerated concrete and preparation method thereof

Abstract

The present invention discloses a waste polishing liquid acid-activated geopolymer regeneration concrete and a preparation method thereof. The contents of each substance in the geopolymer regeneration concrete are 12-20wt% of geopolymer, 72-80wt% of aggregate, and 8-10wt% of water. The contents of each substance in the geopolymer are 60-68wt% of waste red brick micropowder, 25-32wt% of waste polishing liquid, and 7-12wt% of deionized water. The preparation method comprises the following steps: first preparing a geopolymer, then dispersing the geopolymer in water to form a fluid geopolymer; drying coarse aggregate, fine aggregate, and high-brick-concrete construction waste regeneration aggregate of various particle sizes; and mixing the fluid geopolymer and all the aggregates together to obtain the waste polishing liquid acid-activated geopolymer regeneration concrete. The geopolymer prepared by the present invention has excellent performance and can completely replace cement to prepare geopolymer concrete.

Description

Technical Field

[0001] The invention belongs to the technical field of road engineering materials and environmental protection, and particularly relates to a waste polishing liquid acid-activated geopolymer regenerated concrete and a preparation method thereof. Background Art

[0002] With the continuous acceleration of the implementation of projects such as urbanization, old city renovation, and urban village renovation, the contradiction between construction, resources and the environment has become increasingly acute. Urbanization has greatly increased the amount of construction waste generated.

[0003] Construction waste is generally divided into low-brick-concrete concrete waste and high-brick-concrete brick-concrete waste. Processing these two types of waste yields recycled concrete aggregate and brick-concrete aggregate, respectively. Recycled concrete aggregate comes from waste concrete, while recycled brick-concrete aggregate comes from waste bricks and tiles. Concrete and bricks and tiles (i.e., red bricks, red brick fragments, tiles, etc.) are two different types of solid waste. Concrete waste with low brick-concrete content has a higher content of concrete and a lower content of bricks and tiles. Its chemical composition is primarily CaO and CaCO₃, which are alkaline substances, with a relatively small number of internal pores. High-brick-concrete brick-concrete waste has a higher content of bricks and tiles and a relatively low content of concrete. Its chemical composition is primarily SiO₂ and Al₂O₃, which are acidic substances, with a relatively large number of internal pores.

[0004] With the increasing efforts in urban and rural town transformation, many village and town buildings have been demolished, especially those with brick-concrete structures. The resulting brick-concrete construction waste is very large, and appropriate methods should be adopted to treat it as solid waste and transform it into a recyclable resource. Currently, the disposal method for brick-concrete construction waste is to use it as recycled aggregate, roadbed filling material, and mineral admixture after treatment. However, brick-concrete construction waste has poor reactivity, high water absorption, and low strength, which leads to a low utilization rate of brick-concrete construction waste. However, brick-concrete construction waste is rich in alumina and silica, has a certain degree of volcanic ash activity, and has great potential in the preparation of cementitious materials as a precursor material.

[0005] As we all know, cement is the most widely used cementitious material in the construction industry. However, cement production causes severe environmental impact and consumes enormous amounts of energy. Replacing cement with green, resource-based cementitious materials has become an urgent issue. Geopolymer concrete and cement concrete are two different types of concrete. Geopolymer concrete is a mixture of geopolymer mortar and aggregate, while cement concrete is a mixture of cement and aggregate. Currently, research on how to completely replace cement concrete with geopolymer concrete has attracted widespread attention from academia and industry. Geopolymer mortar is the core of geopolymer concrete, used to bond aggregate particles. The performance of geopolymer mortar directly affects the overall quality and comprehensive performance of geopolymer concrete.

[0006] At present, there are many studies on alkali-activated cementitious materials, and their applications are becoming increasingly mature. However, while alkali-activated cementitious materials are developing rapidly, they have also encountered some problems, such as rapid setting, alkali-aggregate reaction, unstable strength, large shrinkage, and cracking of specimens. Moreover, alkali-activated cementitious materials require the use of some professional equipment during the preparation process, which consumes a lot of energy and causes waste of resources. Therefore, it is necessary to explore new activation methods.

[0007] Phosphate-based geopolymers are inorganic aluminosilicate polymers with a three-dimensional network structure composed of [AlO4], [SiO4], and [PO4] tetrahedra. Compared to alkali-activated geopolymers, phosphate-based geopolymers offer advantages such as high strength, excellent high-temperature thermal stability, and low dielectric constant and dielectric loss. Discarded phosphate-based polishing fluid is an industrial waste liquid generated during aluminum processing. Its main component is phosphoric acid, and it also contains large amounts of metal ions such as aluminum and iron. Direct discharge without treatment will cause serious environmental pollution and waste resources. Therefore, the development of a recycled concrete using acid-activated geopolymers from waste polishing fluid and a method for preparing the same are extremely urgent needs in the field of road engineering materials.

[0008] The invention patent with application publication number CN116768537A discloses an acid-activated multi-waste ecological gabion stone and a preparation method thereof, which is prepared from a waste silicon-aluminum source, an acid activator, waste aggregate and water; the content of each substance in the waste silicon-aluminum source is 25-40% blast furnace slag powder, 25-40% fly ash, 5-10% manganese slag powder, 10-20% waste red brick powder, 5-10% waste concrete powder, 5-10% bagasse ash, and 5-10% rice husk ash; the acid activator is a spent phosphoric acid-based polishing liquid; the content of each substance in the waste aggregate is 12-20% waste tailings sand, 12-20% waste red brick sand, and 60-76% recycled concrete coarse aggregate. This technical solution utilizes various types of solid waste materials, and the performance of the gabion stone also meets the requirements, but there are still some problems: (1) Due to the use of various types of waste, the uncertainty of the final stone performance is high; (2) The mortar is not cured, and the performance of the mortar needs to be improved, which affects the performance of the final stone. Summary of the Invention

[0009] In order to solve the problems existing in the prior art, the present invention provides a waste polishing liquid acid-activated geopolymer regeneration concrete. The mass percentages of various substances in the geopolymer regeneration concrete are as follows: 12-20wt% of geopolymer, 72-80wt% of aggregate, and 8-10wt% of water, and the sum of the contents of various substances is 100wt%. The mass percentages of various substances in the geopolymer are as follows: 60-68wt% of waste red brick fine powder, 25-32wt% of waste polishing liquid, and 7-12wt% of deionized water, and the sum of the contents of various substances is 100wt%.

[0010] Preferably, the waste red brick powder is recycled powder obtained after processing of construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 100%; the particle size distribution of the waste red brick powder is between 1-15 μm, wherein the mass percentage of each particle size of the waste red brick powder is 20-40wt% for particle size 8-15 μm and 60-80wt% for particle size 1-8 μm.

[0011] In any of the above schemes, it is preferred that in the waste red brick fine powder with a particle size of 8-15 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 45-50wt%, Al2O3 accounts for 25-30wt%, Fe2O3 accounts for 8-15wt%, CaO accounts for 2-5wt%, MgO accounts for 1-3wt%, Na2O accounts for 1-3wt%, K2O accounts for 1-3wt%, TiO2 accounts for 1-2wt%, P2O5 accounts for 1-2wt%, and MnO accounts for 0.5-1wt%, and the sum of the contents of each chemical substance is 100wt%.

[0012] In any of the above schemes, it is preferred that in the waste red brick fine powder with a particle size of 1-8 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 60-65wt%, Al2O3 accounts for 15-20wt%, Fe2O3 accounts for 5-8wt%, CaO accounts for 2-5wt%, MgO accounts for 1-3wt%, Na2O accounts for 1-3wt%, K2O accounts for 1-3wt%, TiO2 accounts for 1-2wt%, P2O5 accounts for 1-2wt%, and MnO accounts for 0.5-1wt%, and the sum of the contents of each chemical substance is 100wt%.

[0013] In any of the above schemes, it is preferred that the mass percentage of each chemical substance in the waste polishing liquid is 76-80wt% of phosphoric acid, 3-5wt% of sulfuric acid, 1-2wt% of nitric acid, 3-8wt% of Al ions, 2-5wt% of Fe ions, 1-2wt% of Ca ions, 1-2wt% of Mg ions, and 8-11wt% of water, and the sum of the contents of each chemical substance is 100wt%.

[0014] In any of the above schemes, it is preferred that the mass percentage of each substance in the aggregate is 24-30wt% of coarse aggregate, 32-38wt% of fine aggregate, and 35-40wt% of high-quality brick-concrete construction waste recycled aggregate, and the sum of the contents of each substance is 100wt%.

[0015] In any of the above schemes, it is preferred that the coarse aggregate includes three particle sizes, and the mass percentage of each particle size in the coarse aggregate is: particle size 16-19 mm accounts for 25-35wt%, particle size 9.5-16 mm accounts for 32-42wt%, and particle size 4.75-9.5 mm accounts for 30-40wt%, and the sum of the content of coarse aggregate in each particle size is 100wt%; the coarse aggregate includes any one or more of limestone, basalt, and granite.

[0016] In any of the above schemes, it is preferred that the fine aggregate includes seven particle sizes, and the mass percentage of each particle size in the fine aggregate is as follows: particle size 2.36-4.75 mm accounts for 22-28 wt%, particle size 1.18-2.36 mm accounts for 22-28 wt%, particle size 0.6-1.18 mm accounts for 20-25 wt%, particle size 0.3-0.6 mm accounts for 7-10 wt%, particle size 0.15-0.3 mm accounts for 5-8 wt%, particle size 0.075-0.15 mm accounts for 5-8 wt%, and particle size 0-0.075 mm accounts for 5-8 wt%, and the sum of the content of fine aggregate in each particle size is 100 wt%; the fine aggregate includes any one or more of limestone, basalt, and granite.

[0017] In any of the above schemes, it is preferred that the high-brick-concrete construction waste recycled aggregate is a recycled aggregate obtained after processing of construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 60-70%; the high-brick-concrete construction waste recycled aggregate includes three particle sizes, and the mass percentage of each particle size in the high-brick-concrete construction waste recycled aggregate is, particle size 16-19mm accounts for 25-30wt%, particle size 9.5-16mm accounts for 38-45wt%, particle size 4.75-9.5mm accounts for 30-35wt%, and the sum of the content of high-brick-concrete construction waste recycled aggregate of each particle size is 100wt%.

[0018] The present invention also provides a method for preparing waste polishing liquid acid-activated geopolymer regenerated concrete, which is used to prepare any of the waste polishing liquid acid-activated geopolymer regenerated concrete described above, and comprises the following steps in order:

[0019] Step 1: Weigh all raw materials according to the designed material ratio;

[0020] Step 2: Prepare geopolymer according to the designed material ratio and process parameters;

[0021] Step 3: Place the geopolymer and water into a mixing pot and mix them to fully disperse the geopolymer and form a fluid geopolymer.

[0022] Step 4: Place the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high-density brick-concrete construction waste recycled aggregate of each particle size into an oven for drying;

[0023] Step 5: After the drying process is completed, the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high brick-concrete construction waste recycled aggregate of each particle size are placed in a mixing pot and mixed with the fluid geopolymer to obtain the waste polishing liquid acid-activated geopolymer recycled concrete.

[0024] Preferably, in step 2, the method for preparing the geopolymer comprises the following steps in order:

[0025] Step (1): crushing, grinding, and screening construction waste generated by demolishing brick-concrete buildings with a brick-concrete content of 100% to obtain waste red brick powder;

[0026] Step (2): weighing waste red brick micropowder with a particle size of 8-15 μm and a particle size of 1-8 μm according to the designed material ratio, and placing them in an oven for drying at a temperature of 80-100° C. for 2-3 hours; after the drying process is completed, taking out the waste red brick micropowder with a particle size of 8-15 μm and a particle size of 1-8 μm from the oven, and naturally cooling them to room temperature;

[0027] Step (3): According to the designed chemical content ratio, the chemical substances in the waste red brick micropowder with a particle size of 8-15 μm and the particle size of 1-8 μm are tested respectively to ensure that the content of each chemical substance in the waste red brick micropowder of each particle size meets the design requirements;

[0028] Step (4): adding the waste polishing liquid into deionized water according to the designed material ratio to dilute it to a phosphoric acid concentration of 8-12 mol / L, sealing it and naturally cooling it to room temperature to obtain an acid activator;

[0029] Step (5): placing waste red brick powder with a particle size of 8-15 μm and a portion of an acid activator into a mixing pot and mixing them to form a first group of mortar, wherein the mass of the portion of the acid activator is 30-50% of the total amount of the acid activator, the mixing temperature is room temperature, the mixing speed is 80-120 r / min, and the mixing time is 100-150 s;

[0030] Step (6): placing the waste red brick powder with a particle size of 1-8 μm and the remaining acid activator into another mixing pot and mixing them to form a second group of mortar, wherein the mass of the remaining acid activator is 50-70% of the total amount of the acid activator, the mixing temperature is room temperature, the mixing speed is 80-120 r / min, and the mixing time is 100-150 s;

[0031] Step (7): putting the first group of mortar and the second group of mortar into the same mixing pot for mixing at room temperature, a mixing speed of 150-200 r / min, and a mixing time of 200-250 s to obtain geopolymer mortar, which is in a fluid state;

[0032] Step (8): Filling the geopolymer mortar into the forming mold and using a scraper to flatten the upper surface of the geopolymer mortar in the forming mold; placing the forming mold filled with the geopolymer mortar on an electric vibration table, starting the electric vibration table, and starting vibration molding. During the vibration molding process, if a depression occurs, the geopolymer mortar is added to the depressed part;

[0033] Step (9): After the vibration molding is completed, the molding mold and the molded part inside are placed in a curing box for high-temperature curing at a temperature of 60-80°C for 24-36 hours; after the high-temperature curing is completed, the mold is demoulded, and then the molded part is subjected to standard curing under sealed conditions at a curing temperature of room temperature for 28 days to obtain a geopolymer, which is in a solid state.

[0034] In any of the above solutions, preferably, in step 3, the mixing temperature of the geopolymer and water is room temperature, the mixing speed is 50-80 r / min, and the mixing time is 90-120 s.

[0035] In any of the above schemes, preferably, in step 4, the drying temperature of coarse aggregate of each particle size, fine aggregate of each particle size, and high brick-concrete construction waste recycled aggregate of each particle size is 80-100° C. and the drying time is 2-3 hours.

[0036] In any of the above schemes, it is preferred that in step five, the mixing temperature of coarse aggregate of various particle sizes, fine aggregate of various particle sizes, high brick-concrete construction waste recycled aggregate of various particle sizes, and fluid geopolymer is room temperature, the mixing speed is 150-200r / min, and the mixing time is 120-150s.

[0037] In the present invention, the coarse aggregate includes three particle sizes, namely, particle size 16-19 mm, particle size 9.5-16 mm, and particle size 4.75-9.5 mm, that is, 16 mm ≤ particle size < 19 mm, 9.5 mm ≤ particle size < 16 mm, and 4.75 mm ≤ particle size < 9.5 mm. The fine aggregate includes seven particle sizes, namely 2.36-4.75mm, 1.18-2.36mm, 0.6-1.18mm, 0.3-0.6mm, 0.15-0.3mm, 0.075-0.15mm and 0-0.075mm, that is, 2.36mm≤particle size<4.75mm, 1.18mm≤particle size<2.36mm, 0.6mm≤particle size<1.18mm, 0.3mm≤particle size<0.6mm, 0.15mm≤particle size<0.3mm, 0.075mm≤particle size<0.15mm and 0mm≤particle size<0.075mm. Recycled aggregate from high-density brick-concrete construction waste has three particle sizes: 16-19mm, 9.5-16mm, and 4.75-9.5mm, meaning 16mm ≤ < 19mm, 9.5mm ≤ < 16mm, and 4.75mm ≤ < 9.5mm. The particle size distribution of discarded red brick fine powder ranges from 1-15μm, including two size ranges: 8-15μm and 1-8μm, meaning 8μm ≤ ≤ 15μm and 1μm ≤ < 8μm. For each particle size, the material passes through the upper and lower sieve holes in sequence to obtain a particle size between the upper and lower sieve holes, for example: the particle size is 1.18-2.36mm (1.18mm≤particle size<2.36mm), that is, the material passes through the 2.36mm sieve hole and the 1.18mm sieve hole in sequence to obtain a particle size between 1.18-2.36mm.

[0038] The technical principle of the present invention: H in the acid activator + Reacts with Al2O3 in the precursor, breaks the Al-O bond, and reacts with SiO4 4- 、AlO4 2- and PO4 3-The waste polishing liquid of the present invention has the advantage of being an acid activator in that it can react with waste red brick powder to form phosphorus-oxygen tetrahedrons, which can be connected with the layered structure of the waste polishing liquid to form a more stable three-dimensional network structure, and can also balance the Al 3+ The positive charge makes the entire structure electrically neutral, and the Al contained in the waste polishing liquid 3+ and other metal ions and PO4 in waste polishing liquid 3- 、H + and [H9Si2O8] + Plasma condensation forms more gel phases, so the mechanical properties of the gel material stimulated by the waste polishing liquid of the present invention are more excellent.

[0039] The present invention has been proven through a large number of tests that the optimal concentration range is 8-12 mol / L when the waste polishing liquid is diluted with deionized water. When the acid concentration is too high, the heat released in the initial stage of the reaction is large, causing the slurry to set prematurely, hindering the depolymerization of aluminosilicate and resulting in incomplete reaction, thereby leaving a large amount of unreacted precursors in the microstructure. When the acid concentration is too low, there is too much free water in the solution, and the excess water does not participate in the polymerization reaction and gradually dissipates during the curing process, resulting in more pores in the geopolymer structure. At the same time, too low an acid concentration will also cause Al 3+ Priority and PO3 4- An amorphous structure mainly composed of P-O-Al is formed, which also makes its structure loose and porous, reducing the strength of the geopolymer.

[0040] The present invention has been proved through a large number of tests that after the geopolymer mortar is vibrated and formed, it is placed in a curing box for high-temperature curing. The curing temperature is 60-80°C and the curing time is 24-36 hours. The curing temperature and curing time are in the optimal range.

[0041] During geopolymerization, depolymerization and polymerization occur simultaneously. Low reaction temperatures facilitate a more complete depolymerization reaction, dissolving more silicon and aluminum and promoting the formation of a larger gel phase. However, this hinders the removal of water and hydroxyl groups from the geopolymer during the polycondensation phase, thus affecting its compressive strength. Conversely, high reaction temperatures, while beneficial for the removal of water and hydroxyl groups from the geopolymer, shorten the depolymerization process and affect the dissolution of silicon and aluminum from the precursor. Furthermore, excessively high reaction temperatures can cause water in the molded part to evaporate too quickly, resulting in inconsistent shrinkage rates between the surface and interior of the molded part, causing microcracks and compressive strength.

[0042] When the curing time is short, the reaction between the precursor and the acid activator is incomplete, and some hydroxyl groups in the molded parts are difficult to remove; appropriately extending the curing time can effectively optimize the product structure and improve the performance of the geopolymer. If the curing time is too long, the strength of the geopolymer will not be significantly improved, or even not improved at all, wasting time and cost.

[0043] The waste polishing liquid acid-activated geopolymer recycled concrete and its preparation method of the present invention involve numerous parameters, including formulation parameters and process parameters, which require synergy to achieve the intended technical effects of the present invention. In particular, the content of each chemical substance in the two particle size waste red brick micropowders, as well as the fact that when preparing the geopolymer, the two particle size waste red brick micropowders need to react separately with an acid activator to form mortars, and then the two sets of mortars are mixed to prepare the geopolymer mortar. Throughout the entire process of preparing the geopolymer recycled concrete, the selection and addition amount of each substance, the order of addition of each substance, and the process parameters of each step are also very important, and the formulation parameters and process parameters need to work synergistically.

[0044] In the present invention, the waste red brick powder and high brick-concrete construction waste recycled aggregate used are recycled materials obtained after processing of construction waste generated by the demolition of brick-concrete buildings. These two materials are different from solid waste materials such as industrial waste slag (such as steel slag, slag, zinc slag, manganese slag, etc.), coal liquefaction residue (such as direct coal liquefaction residue, indirect coal liquefaction residue, etc.), and concrete construction waste (low brick-concrete content). The methods of obtaining these solid waste materials, the realization principles, the physical and chemical properties, etc. are all different.

[0045] In the present invention, the mixing pot, electric vibrating table, oven, curing box, crushing equipment, grinding equipment, screening equipment, etc. used are all traditional equipment in this field. There are no special requirements for the equipment model and they can be selected according to actual usage. It is only necessary to ensure that key parameters such as mixing speed, mixing time, drying temperature, drying time, curing temperature, and curing time meet the requirements of the present invention.

[0046] The waste polishing liquid acid-activated geopolymer regenerated concrete and the preparation method thereof of the present invention have the following beneficial effects:

[0047] (1) The present invention uses waste red brick powder as a precursor and waste polishing liquid as an acid activator to prepare geopolymer mortar, and then obtains geopolymer through high-temperature curing. The geopolymer has excellent mechanical properties and water absorption rate.

[0048] (2) The geopolymer of the present invention can completely replace cement to prepare geopolymer concrete, which has excellent mechanical properties and durability.

[0049] (3) The present invention also comprehensively utilizes waste materials such as discarded red brick powder, discarded polishing liquid, and recycled aggregates from high-brick-concrete construction waste, thereby reducing carbon emissions and promoting the utilization of renewable resources and the green development of the construction industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A flowchart of a preferred embodiment of the waste polishing liquid acid-activated geopolymer regenerated concrete and a preparation method thereof according to the present invention;

[0051] Figure 2 for Figure 1 Actual photos of waste red brick powder used in the examples shown;

[0052] Figure 3 for Figure 1 Actual photos of the waste polishing liquid used in the illustrated embodiment;

[0053] Figure 4 for Figure 1 Actual photos of the aggregates used in the illustrated embodiments, wherein: (a) is coarse aggregate, (b) is fine aggregate, and (c) is recycled aggregate from high-quality brick-concrete construction waste;

[0054] Figure 5 for Figure 1 Photos of the geopolymer prepared in the examples shown, where: (a) shows the state before high-temperature curing, and (b) shows the state after high-temperature curing;

[0055] Figure 6 for Figure 1 Microscopic morphology photos of geopolymers prepared in the examples shown;

[0056] Figure 7 for Figure 1 XRD test pattern of the geopolymer prepared in the embodiment shown;

[0057] Figure 8 for Figure 1 Actual photos of the geopolymer recycled concrete prepared in the examples shown. DETAILED DESCRIPTION

[0058] In order to further understand the content of the present invention, the present invention will be described in detail below with reference to specific embodiments.

[0059] Example 1:

[0060] According to a preferred embodiment of the waste polishing liquid acid-activated geopolymer regenerated concrete of the present invention, the mass percentages of the various substances in the geopolymer regenerated concrete are: 16wt% of geopolymer, 76wt% of aggregate, and 8wt% of water; the mass percentages of the various substances in the geopolymer are: 64wt% of waste red brick powder, 27wt% of waste polishing liquid, and 9wt% of deionized water.

[0061] The waste red brick micropowder is recycled micropowder obtained by processing construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 100%; the particle size distribution of the waste red brick micropowder is between 1-15 μm, wherein the mass percentage of each particle size of the waste red brick micropowder is: the particle size of 8-15 μm accounts for 30wt%, and the particle size of 1-8 μm accounts for 70wt%.

[0062] In the waste red brick fine powder with a particle size of 8-15 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 48wt%, Al2O3 accounts for 28wt%, Fe2O3 accounts for 11wt%, CaO accounts for 3wt%, MgO accounts for 2wt%, Na2O accounts for 2wt%, K2O accounts for 2wt%, TiO2 accounts for 1.5wt%, P2O5 accounts for 1.5wt%, and MnO accounts for 1wt%.

[0063] In the waste red brick fine powder with a particle size of 1-8 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 63wt%, Al2O3 accounts for 18wt%, Fe2O3 accounts for 6wt%, CaO accounts for 3wt%, MgO accounts for 2wt%, Na2O accounts for 2wt%, K2O accounts for 2wt%, TiO2 accounts for 1.5wt%, P2O5 accounts for 1.5wt%, and MnO accounts for 1wt%.

[0064] The mass percentages of the chemical substances in the waste polishing liquid are as follows: 77 wt% of phosphoric acid, 4 wt% of sulfuric acid, 1 wt% of nitric acid, 4 wt% of Al ions, 3 wt% of Fe ions, 1 wt% of Ca ions, 1 wt% of Mg ions, and 9 wt% of water.

[0065] The mass percentages of various substances in the aggregate are as follows: 27 wt% of coarse aggregate, 35 wt% of fine aggregate, and 38 wt% of recycled aggregate from high-density brick-concrete construction waste.

[0066] The coarse aggregate includes three particle sizes, and the mass percentage of each particle size in the coarse aggregate is: particle size 16-19 mm accounts for 30wt%, particle size 9.5-16 mm accounts for 35wt%, and particle size 4.75-9.5 mm accounts for 35wt%. The coarse aggregate is limestone.

[0067] The fine aggregate includes seven particle sizes, and the mass percentage of each particle size in the fine aggregate is: particle size 2.36-4.75 mm accounts for 25wt%, particle size 1.18-2.36 mm accounts for 25wt%, particle size 0.6-1.18 mm accounts for 22wt%, particle size 0.3-0.6 mm accounts for 8wt%, particle size 0.15-0.3 mm accounts for 6wt%, particle size 0.075-0.15 mm accounts for 7wt%, and particle size 0-0.075 mm accounts for 7wt%. The fine aggregate is limestone.

[0068] The high-quality brick-concrete construction waste recycled aggregate is a recycled aggregate obtained by processing the construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 65%; the high-quality brick-concrete construction waste recycled aggregate includes three particle sizes, and the mass percentage of each particle size in the high-quality brick-concrete construction waste recycled aggregate is: particle size 16-19mm accounts for 28wt%, particle size 9.5-16mm accounts for 40wt%, and particle size 4.75-9.5mm accounts for 32wt%.

[0069] like Figure 1 As shown, this embodiment also provides a method for preparing waste polishing liquid acid-activated geopolymer regenerated concrete, which is used to prepare the above waste polishing liquid acid-activated geopolymer regenerated concrete, and includes the following steps in order:

[0070] Step 1: Weigh all raw materials according to the designed material ratio;

[0071] Step 2: Prepare geopolymer according to the designed material ratio and process parameters;

[0072] Step 3: Place the geopolymer and water into a mixing pot and mix them to fully disperse the geopolymer and form a fluid geopolymer.

[0073] Step 4: Place the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high-density brick-concrete construction waste recycled aggregate of each particle size into an oven for drying;

[0074] Step 5: After the drying process is completed, the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high brick-concrete construction waste recycled aggregate of each particle size are placed in a mixing pot and mixed with the fluid geopolymer to obtain the waste polishing liquid acid-activated geopolymer recycled concrete.

[0075] In step 2, the method for preparing the geopolymer comprises the following steps in order:

[0076] Step (1): crushing, grinding, and screening construction waste generated by demolishing brick-concrete buildings with a brick-concrete content of 100% to obtain waste red brick powder;

[0077] Step (2): weighing waste red brick micropowder with a particle size of 8-15 μm and a particle size of 1-8 μm according to the designed material ratio, and placing them in an oven for drying at a temperature of 90° C. and a drying time of 2.5 h; after the drying process is completed, taking out the waste red brick micropowder with a particle size of 8-15 μm and a particle size of 1-8 μm from the oven respectively and cooling them naturally to room temperature;

[0078] Step (3): According to the designed chemical content ratio, the chemical substances in the waste red brick micropowder with a particle size of 8-15 μm and the particle size of 1-8 μm are tested respectively to ensure that the content of each chemical substance in the waste red brick micropowder of each particle size meets the design requirements;

[0079] Step (4): adding the waste polishing liquid into deionized water according to the designed material ratio to dilute it to a phosphoric acid concentration of 10 mol / L, sealing it and naturally cooling it to room temperature to obtain an acid activator;

[0080] Step (5): placing waste red brick powder with a particle size of 8-15 μm and a portion of an acid activator into a mixing pot and mixing them to form a first group of mortar, wherein the mass of the portion of the acid activator is 40% of the total amount of the acid activator, the mixing temperature is room temperature, the mixing speed is 100 r / min, and the mixing time is 125 s;

[0081] Step (6): placing the waste red brick powder with a particle size of 1-8 μm and the remaining acid activator into another mixing pot and mixing them to form a second group of mortar, wherein the mass of the remaining acid activator is 60% of the total amount of the acid activator, the mixing temperature is room temperature, the mixing speed is 100 r / min, and the mixing time is 125 s;

[0082] Step (7): putting the first group of mortar and the second group of mortar into the same mixing pot for mixing at room temperature, a mixing speed of 175 r / min, and a mixing time of 225 s to obtain a geopolymer mortar, which is in a fluid state;

[0083] Step (8): Filling the geopolymer mortar into the forming mold and using a scraper to flatten the upper surface of the geopolymer mortar in the forming mold; placing the forming mold filled with the geopolymer mortar on an electric vibration table, starting the electric vibration table, and starting vibration molding. During the vibration molding process, if a depression occurs, the geopolymer mortar is added to the depressed part;

[0084] Step (9): After the vibration molding is completed, the molding mold and the molded part inside are placed in a curing box for high-temperature curing at a temperature of 70° C. for 30 hours. After the high-temperature curing is completed, the mold is demoulded, and then the molded part is subjected to standard curing under sealed conditions at room temperature for 28 days to obtain a geopolymer, which is in a solid state.

[0085] In step 3, the mixing temperature of geopolymer and water is room temperature, the mixing speed is 65 r / min, and the mixing time is 105 s.

[0086] In step 4, the drying temperature of the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high-density brick-concrete construction waste recycled aggregate of each particle size is 90° C. and the drying time is 2.5 h.

[0087] In step five, the mixing temperature of coarse aggregate of various particle sizes, fine aggregate of various particle sizes, high brick-concrete construction waste recycled aggregate of various particle sizes, and fluid geopolymer is room temperature, the mixing speed is 175r / min, and the mixing time is 135s.

[0088] In this embodiment, the waste red brick powder used is as follows: Figure 2 As shown; the waste polishing liquid used is as follows Figure 3 As shown; the aggregate used is as Figure 4 As shown, (a) is coarse aggregate, (b) is fine aggregate, and (c) is recycled aggregate from high-density brick-concrete construction waste; the prepared geopolymer is as follows Figure 5 As shown, (a) is the state before high temperature curing, (b) is the state after high temperature curing; the microscopic morphology of the prepared geopolymer is as shown Figure 6 As shown, the XRD test pattern is as follows Figure 7 As shown; the prepared geopolymer recycled concrete (molded specimen) is as shown Figure 8 shown.

[0089] from Figure 6 and Figure 7 It can be seen that a large amount of gel phase is generated after the reaction of geopolymer. Silicate ions, aluminate ions and phosphate ions combine to form a three-dimensional network space structure, which corresponds to the diffraction peak in the XRD spectrum. The basic unit is -Si-O-Al-OPO-. The silicon-oxygen tetrahedron and aluminum-oxygen tetrahedron generated by the reaction are connected to each other to form a layered structure, which can effectively improve the mechanical properties of geopolymer.

[0090] The waste polishing liquid acid-activated geopolymer regenerated concrete and its preparation method of this embodiment have the following beneficial effects:

[0091] (1) Using waste red brick fine powder as a precursor and waste polishing fluid as an acid activator to prepare geopolymer mortar, and then curing it at high temperature to obtain geopolymer, the geopolymer has excellent mechanical properties. (2) The geopolymer can completely replace cement to prepare geopolymer concrete, which has excellent road performance. (3) At the same time, waste materials such as waste red brick fine powder, waste polishing fluid, and recycled aggregate from high-density brick-concrete construction waste are comprehensively utilized to reduce carbon emissions.

[0092] Example 2:

[0093] According to another preferred embodiment of the waste polishing liquid acid-activated geopolymer regenerated concrete and its preparation method of the present invention, its material ratio, process steps, technical principles, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0094] The mass percentages of the various substances in the geopolymer recycled concrete are: 12 wt% of geopolymer, 80 wt% of aggregate, and 8 wt% of water; the mass percentages of the various substances in the geopolymer are: 60 wt% of waste red brick powder, 32 wt% of waste polishing liquid, and 8 wt% of deionized water.

[0095] The waste red brick micropowder is recycled micropowder obtained by processing construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 100%; the particle size distribution of the waste red brick micropowder is between 1-15 μm, and the mass percentage of each particle size of the waste red brick micropowder is: particle size 8-15 μm accounts for 20wt%, and particle size 1-8 μm accounts for 80wt%.

[0096] In the waste red brick fine powder with a particle size of 8-15 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 45wt%, Al2O3 accounts for 30wt%, Fe2O3 accounts for 8wt%, CaO accounts for 5wt%, MgO accounts for 1wt%, Na2O accounts for 3wt%, K2O accounts for 3wt%, TiO2 accounts for 2wt%, P2O5 accounts for 2wt%, and MnO accounts for 1wt%.

[0097] In the waste red brick fine powder with a particle size of 1-8 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 60wt%, Al2O3 accounts for 20wt%, Fe2O3 accounts for 5wt%, CaO accounts for 5wt%, MgO accounts for 1wt%, Na2O accounts for 1wt%, K2O accounts for 3wt%, TiO2 accounts for 2wt%, P2O5 accounts for 2wt%, and MnO accounts for 1wt%.

[0098] The mass percentages of the chemical substances in the waste polishing liquid are as follows: 76 wt% of phosphoric acid, 3 wt% of sulfuric acid, 2 wt% of nitric acid, 3 wt% of Al ions, 5 wt% of Fe ions, 2 wt% of Ca ions, 1 wt% of Mg ions, and 8 wt% of water.

[0099] The mass percentages of various substances in the aggregate are as follows: 24 wt% of coarse aggregate, 36 wt% of fine aggregate, and 40 wt% of recycled aggregate from high-density brick-concrete construction waste.

[0100] The coarse aggregate includes three particle sizes, and the mass percentage of each particle size in the coarse aggregate is: particle size 16-19 mm accounts for 25wt%, particle size 9.5-16 mm accounts for 42wt%, and particle size 4.75-9.5 mm accounts for 33wt%. The coarse aggregate is limestone.

[0101] The fine aggregate includes seven particle sizes, and the mass percentage of each particle size in the fine aggregate is: particle size 2.36-4.75 mm accounts for 22wt%, particle size 1.18-2.36 mm accounts for 28wt%, particle size 0.6-1.18 mm accounts for 20wt%, particle size 0.3-0.6 mm accounts for 10wt%, particle size 0.15-0.3 mm accounts for 5wt%, particle size 0.075-0.15 mm accounts for 8wt%, and particle size 0-0.075 mm accounts for 7wt%. The fine aggregate is limestone.

[0102] The high-quality brick-concrete construction waste recycled aggregate is a recycled aggregate obtained by processing the construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 70%; the high-quality brick-concrete construction waste recycled aggregate includes three particle sizes, and the mass percentage of each particle size in the high-quality brick-concrete construction waste recycled aggregate is: particle size 16-19mm accounts for 25wt%, particle size 9.5-16mm accounts for 45wt%, and particle size 4.75-9.5mm accounts for 30wt%.

[0103] In step 2, the main preparation parameters of the geopolymer include: placing the waste red brick powder with a particle size of 8-15 μm and the particle size of 1-8 μm in an oven for drying, the drying temperature is 80 ° C, and the drying time is 3 hours; adding the waste polishing liquid into deionized water for dilution to a phosphoric acid concentration of 8 mol / L; placing the waste red brick powder with a particle size of 8-15 μm and 30% of the acid activator into a mixing pot for mixing to form the first group of mortar, the mixing temperature is room temperature, the mixing speed is 80 r / min, and the mixing time is 1 50s; put the waste red brick powder with a particle size of 1-8μm and 70% of the acid activator into another mixing pot for mixing to form a second group of mortar, the mixing temperature is room temperature, the mixing speed is 80r / min, and the mixing time is 150s; put the first group of mortar and the second group of mortar into the same mixing pot for mixing, the mixing temperature is room temperature, the mixing speed is 150r / min, and the mixing time is 250s; put the forming mold and the molded parts inside it into the curing box for high temperature curing, the curing temperature is 60℃, and the curing time is 36h.

[0104] In step 3, the mixing temperature of geopolymer and water is room temperature, the mixing speed is 50 r / min, and the mixing time is 120 s.

[0105] In step 4, the drying temperature of the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high-density brick-concrete construction waste recycled aggregate of each particle size is 80° C. and the drying time is 3 hours.

[0106] In step five, the mixing temperature of coarse aggregate of various particle sizes, fine aggregate of various particle sizes, high brick-concrete construction waste recycled aggregate of various particle sizes, and fluid geopolymer is room temperature, the mixing speed is 150r / min, and the mixing time is 150s.

[0107] Example 3:

[0108] According to another preferred embodiment of the waste polishing liquid acid-activated geopolymer regenerated concrete and its preparation method of the present invention, its material ratio, process steps, technical principles, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0109] The mass percentages of the various substances in the geopolymer recycled concrete are: 20 wt% of geopolymer, 72 wt% of aggregate, and 8 wt% of water; the mass percentages of the various substances in the geopolymer are: 68 wt% of waste red brick powder, 25 wt% of waste polishing liquid, and 7 wt% of deionized water.

[0110] The waste red brick micropowder is recycled micropowder obtained by processing construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 100%; the particle size distribution of the waste red brick micropowder is between 1-15 μm, and the mass percentage of each particle size of the waste red brick micropowder is as follows: the particle size of 8-15 μm accounts for 40wt%, and the particle size of 1-8 μm accounts for 60wt%.

[0111] In the waste red brick fine powder with a particle size of 8-15 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 50wt%, Al2O3 accounts for 25wt%, Fe2O3 accounts for 15wt%, CaO accounts for 2wt%, MgO accounts for 3wt%, Na2O accounts for 1wt%, K2O accounts for 1wt%, TiO2 accounts for 1wt%, P2O5 accounts for 1wt%, and MnO accounts for 1wt%.

[0112] In the waste red brick fine powder with a particle size of 1-8 μm, the mass percentage of each chemical substance in the waste red brick fine powder is: SiO2 accounts for 65wt%, Al2O3 accounts for 15wt%, Fe2O3 accounts for 8wt%, CaO accounts for 2wt%, MgO accounts for 3wt%, Na2O accounts for 3wt%, K2O accounts for 1wt%, TiO2 accounts for 1wt%, P2O5 accounts for 1wt%, and MnO accounts for 1wt%.

[0113] The mass percentages of the chemical substances in the waste polishing liquid are as follows: 80 wt% of phosphoric acid, 3 wt% of sulfuric acid, 1 wt% of nitric acid, 4 wt% of Al ions, 2 wt% of Fe ions, 1 wt% of Ca ions, 1 wt% of Mg ions, and 8 wt% of water.

[0114] The mass percentages of various substances in the aggregate are as follows: 30 wt% of coarse aggregate, 32 wt% of fine aggregate, and 38 wt% of recycled aggregate from high-density brick-concrete construction waste.

[0115] The coarse aggregate includes three particle sizes, and the mass percentage of each particle size in the coarse aggregate is: particle size 16-19 mm accounts for 35wt%, particle size 9.5-16 mm accounts for 32wt%, and particle size 4.75-9.5 mm accounts for 33wt%. The coarse aggregate is limestone.

[0116] The fine aggregate includes seven particle sizes, and the mass percentage of each particle size in the fine aggregate is: particle size 2.36-4.75 mm accounts for 28wt%, particle size 1.18-2.36 mm accounts for 22wt%, particle size 0.6-1.18 mm accounts for 25wt%, particle size 0.3-0.6 mm accounts for 7wt%, particle size 0.15-0.3 mm accounts for 8wt%, particle size 0.075-0.15 mm accounts for 5wt%, and particle size 0-0.075 mm accounts for 5wt%. The fine aggregate is limestone.

[0117] The high-brick-concrete construction waste recycled aggregate is a recycled aggregate obtained by processing the construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 60%; the high-brick-concrete construction waste recycled aggregate includes three particle sizes, and the mass percentage of each particle size in the high-brick-concrete construction waste recycled aggregate is: particle size 16-19mm accounts for 30wt%, particle size 9.5-16mm accounts for 38wt%, and particle size 4.75-9.5mm accounts for 32wt%.

[0118] In step 2, the main preparation parameters of the geopolymer include: placing the waste red brick powder with a particle size of 8-15 μm and the particle size of 1-8 μm in an oven for drying, the drying temperature is 100 ° C, and the drying time is 2 hours; the waste polishing liquid is added to deionized water for dilution to a phosphoric acid concentration of 12 mol / L; the waste red brick powder with a particle size of 8-15 μm and 50% of the acid activator are placed in a mixing pot for mixing to form the first group of mortar, the mixing temperature is room temperature, the mixing speed is 120 r / min, and the mixing time is 100s; put the waste red brick powder with a particle size of 1-8μm and 50% of the acid activator into another mixing pot for mixing to form a second group of mortar, the mixing temperature is room temperature, the mixing speed is 120r / min, and the mixing time is 100s; put the first group of mortar and the second group of mortar into the same mixing pot for mixing, the mixing temperature is room temperature, the mixing speed is 200r / min, and the mixing time is 200s; put the forming mold and the molded parts inside it into the curing box for high-temperature curing, the curing temperature is 80℃, and the curing time is 24h.

[0119] In step 3, the mixing temperature of geopolymer and water is room temperature, the mixing speed is 80 r / min, and the mixing time is 90 s.

[0120] In step 4, the drying temperature of coarse aggregate of each particle size, fine aggregate of each particle size, and high brick-concrete construction waste recycled aggregate of each particle size is 100° C. and the drying time is 2 h.

[0121] In step five, the mixing temperature of coarse aggregate of various particle sizes, fine aggregate of various particle sizes, high brick-concrete construction waste recycled aggregate of various particle sizes, and fluid geopolymer is room temperature, the mixing speed is 200r / min, and the mixing time is 120s.

[0122] Mechanical property tests and water absorption tests were performed on the geopolymers prepared in the three examples described above. Each test followed the corresponding test procedures, such as the "Testing Procedures for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011). The test results are shown in Table 1. Mechanical property tests and durability tests were also performed on the geopolymer-mixed recycled concrete prepared in the three examples described above. Each test followed the corresponding test procedures, such as the "Standard for Test Methods for Physical and Mechanical Properties of Concrete" (GB / T 50081-2019). The test results are shown in Table 2. The test equipment, test environment, test conditions, and specimen shape and size were identical for each test.

[0123] Table 1 Mechanical properties and water absorption test results of geopolymers

[0124]

[0125] Table 2 Mechanical properties and durability test results of geopolymer recycled concrete

[0126]

[0127] It can be seen from the test results in Table 1 and Table 2 that the geopolymers prepared in the above three embodiments have excellent mechanical properties and water absorption, and the prepared geopolymer recycled concrete has good mechanical properties and durability.

[0128] The coarse aggregate and fine aggregate used in the above embodiments were purchased from Beijing Municipal Road and Bridge Building Materials Group Co., Ltd.; the brick-concrete construction waste recycled aggregate used was purchased from Beijing Urban Green Source Environmental Protection Technology Co., Ltd., mainly from construction waste generated by the demolition of brick-concrete buildings within 30 kilometers of the disposal site; the waste polishing liquid used was purchased from Beijing Tianhai Nanjiao Electroplating Factory.

[0129] Special Note: The technical solution of this invention involves numerous parameters, and the synergistic effects between these parameters must be comprehensively considered to achieve the beneficial effects and significant improvements of this invention. Furthermore, the value ranges of each parameter in the technical solution were obtained through extensive testing. The inventors have recorded extensive experimental data for each parameter and their combinations. Due to space limitations, the specific experimental data will not be disclosed here.

[0130] Those skilled in the art will readily appreciate that the waste polishing fluid acid-activated geopolymer regenerated concrete and its preparation method of the present invention include any combination of the invention summary and detailed description of the present invention specification, as well as the various components shown in the accompanying drawings. Due to space limitations and to simplify the description, each solution formed by these combinations is not described one by one. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A waste polishing liquid acid-activated geopolymer regeneration concrete, characterized in that: The mass percentage of each substance in the geopolymer recycled concrete is 12-20wt% of geopolymer mortar, 72-80wt% of aggregate, and 8-10wt% of water, and the sum of the contents of each substance is 100wt%; the mass percentage of each substance in the geopolymer mortar is 60-68wt% of waste red brick powder, 25-32wt% of waste polishing liquid, and 7-12wt% of deionized water, and the sum of the contents of each substance is 100wt%; The waste red brick powder is recycled powder obtained by processing construction waste generated by the demolition of brick-concrete buildings, and the brick-concrete content is 100%. The particle size distribution of the waste red brick powder is between 1-15 μm, wherein the mass percentage of each particle size in the waste red brick powder is 20-40% by weight of the particle size of 8-15 μm and 60-80% by weight of the particle size of 1-8 μm. The weight percentage of each chemical substance in the waste polishing liquid is 76-80wt% of phosphoric acid, 3-5wt% of sulfuric acid, 1-2wt% of nitric acid, 3-8wt% of Al ions, 2-5wt% of Fe ions, 1-2wt% of Ca ions, 1-2wt% of Mg ions, and 8-11wt% of water, and the sum of the contents of each chemical substance is 100wt%; The mass percentage of each substance in the aggregate is 24-30wt% of coarse aggregate, 32-38wt% of fine aggregate, and 35-40wt% of recycled aggregate from high-quality brick-concrete construction waste, and the sum of the contents of each substance is 100wt%; The coarse aggregate includes three particle sizes, and the mass percentage of each particle size in the coarse aggregate is 25-35wt% for a particle size of 16-19mm, 32-42wt% for a particle size of 9.5-16mm, and 30-40wt% for a particle size of 4.75-9.5mm. The sum of the contents of the coarse aggregates of each particle size is 100wt%. The fine aggregate comprises seven particle sizes, and the mass percentage of each particle size in the fine aggregate is as follows: particle size 2.36-4.75 mm accounts for 22-28 wt%, particle size 1.18-2.36 mm accounts for 22-28 wt%, particle size 0.6-1.18 mm accounts for 20-25 wt%, particle size 0.3-0.6 mm accounts for 7-10 wt%, particle size 0.15-0.3 mm accounts for 5-8 wt%, particle size 0.075-0.15 mm accounts for 5-8 wt%, and particle size 0-0.075 mm accounts for 5-8 wt%, and the sum of the content of fine aggregate of each particle size is 100 wt%. The high-quality brick-concrete construction waste recycled aggregate is a recycled aggregate obtained after processing of construction waste generated by the demolition of brick-concrete buildings, and its brick-concrete content is 60-70%; the high-quality brick-concrete construction waste recycled aggregate includes three particle sizes, and the mass percentage of each particle size in the high-quality brick-concrete construction waste recycled aggregate is 25-30wt% for particle size 16-19mm, 38-45wt% for particle size 9.5-16mm, and 30-35wt% for particle size 4.75-9.5mm. The sum of the content of high-quality brick-concrete construction waste recycled aggregate in each particle size is 100wt%.

2. The waste polishing liquid acid-activated geopolymer regeneration concrete according to claim 1, characterized in that: In the waste red brick fine powder with a particle size of 8-15 μm, the mass percentage of each chemical substance in the waste red brick fine powder is SiO2 accounting for 45-50wt%, Al2O3 accounting for 25-30wt%, Fe2O3 accounting for 8-15wt%, CaO accounting for 2-5wt%, MgO accounting for 1-3wt%, Na2O accounting for 1-3wt%, K2O accounting for 1-3wt%, TiO2 accounting for 1-2wt%, P2O5 accounting for 1-2wt%, and MnO accounting for 0.5-1wt%, and the sum of the contents of each chemical substance is 100wt%.

3. The waste polishing liquid acid-activated geopolymer regeneration concrete according to claim 2, characterized in that: In the waste red brick fine powder with a particle size of 1-8 μm, the mass percentage of each chemical substance in the waste red brick fine powder is SiO2 accounting for 60-65wt%, Al2O3 accounting for 15-20wt%, Fe2O3 accounting for 5-8wt%, CaO accounting for 2-5wt%, MgO accounting for 1-3wt%, Na2O accounting for 1-3wt%, K2O accounting for 1-3wt%, TiO2 accounting for 1-2wt%, P2O5 accounting for 1-2wt%, and MnO accounting for 0.5-1wt%, and the sum of the contents of each chemical substance is 100wt%.

4. The waste polishing liquid acid-activated geopolymer regeneration concrete according to claim 3, characterized in that: The coarse aggregate and the fine aggregate both include any one or more of limestone, basalt, and granite.

5. A method for preparing acid-activated geopolymer regenerated concrete from waste polishing liquid, characterized in that: The method for preparing the waste polishing liquid acid-activated geopolymer regenerated concrete according to any one of claims 1 to 4 comprises the following steps in order: Step 1: Weigh all raw materials according to the designed material ratio; Step 2: Prepare geopolymer mortar according to the designed material ratio and process parameters; Step 3: Place the geopolymer mortar and water into a mixing pot and mix them to ensure that the geopolymer mortar is fully dispersed and remains fluid; Step 4: Place the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high-density brick-concrete construction waste recycled aggregate of each particle size into an oven for drying; Step 5: After the drying process is completed, the coarse aggregate of each particle size, the fine aggregate of each particle size, and the high brick-concrete construction waste recycled aggregate of each particle size are put into the mixing pot and mixed with the fluid geopolymer mortar to obtain the waste polishing liquid acid-activated geopolymer recycled concrete.

6. The method for preparing acid-activated geopolymer regenerated concrete from waste polishing liquid according to claim 5, characterized in that: In step 2, the method for preparing the geopolymer mortar comprises the following steps in order: Step (1): crushing, grinding and screening construction waste generated by demolishing brick-concrete buildings with a brick-concrete content of 100% to obtain waste red brick powder; Step (2): weighing waste red brick fine powder with a particle size of 8-15 μm and a particle size of 1-8 μm according to the designed material ratio, and placing them in an oven for drying at a temperature of 80-100°C and a drying time of 2-3 hours; after the drying process is completed, taking out the waste red brick fine powder with a particle size of 8-15 μm and a particle size of 1-8 μm from the oven respectively and cooling them naturally to room temperature; Step (3): According to the designed chemical content ratio, test the chemical substances in the waste red brick micropowder with a particle size of 8-15 μm and a particle size of 1-8 μm respectively to ensure that the content of each chemical substance in the waste red brick micropowder of each particle size meets the design requirements; Step (4): according to the designed material ratio, the waste polishing liquid is added into deionized water for dilution to a phosphoric acid concentration of 8-12 mol / L, sealed and naturally cooled to room temperature to obtain an acid activator; Step (5): Place waste red brick powder with a particle size of 8-15 μm and a portion of the acid activator into a mixing pot and mix to form a first group of mortar, wherein the mass of the portion of the acid activator is 30-50% of the total amount of the acid activator, the mixing temperature is room temperature, the mixing speed is 80-120 r / min, and the mixing time is 100-150 s; Step (6): Place the waste red brick powder with a particle size of 1-8 μm and the remaining acid activator into another mixing pot and mix them to form a second group of mortar, wherein the mass of the remaining acid activator is 50-70% of the total amount of the acid activator, the mixing temperature is room temperature, the mixing speed is 80-120 r / min, and the mixing time is 100-150 s; Step (7): Put the first group of mortar and the second group of mortar into the same mixing pot for mixing at room temperature, a mixing speed of 150-200 r / min, and a mixing time of 200-250 s to obtain geopolymer mortar.

7. The method for preparing acid-activated geopolymer regenerated concrete from waste polishing liquid according to claim 6, characterized in that: In step 3, the mixing temperature of the geopolymer mortar and water is room temperature, the mixing speed is 50-80 r / min, and the mixing time is 90-120 s.

8. The method for preparing acid-activated geopolymer regenerated concrete from waste polishing liquid according to claim 7, characterized in that: In step 4, the drying temperature of coarse aggregate of each particle size, fine aggregate of each particle size, and high brick-concrete construction waste recycled aggregate of each particle size is 80-100° C. and the drying time is 2-3 hours.

9. The method for preparing acid-activated geopolymer regenerated concrete from waste polishing liquid according to claim 8, characterized in that: In step five, the mixing temperature of coarse aggregate of various particle sizes, fine aggregate of various particle sizes, high brick-concrete construction waste recycled aggregate of various particle sizes, and fluid geopolymer mortar is room temperature, the mixing speed is 150-200r / min, and the mixing time is 120-150s.

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