Method for preparing geopolymer through cooperation of household garbage incineration fly ash and industrial solid waste

Abstract

The invention relates to the technical field of solid waste treatment and resource utilization, in particular to a method for preparing a geopolymer from household garbage incineration fly ash cooperating with industrial solid waste, which comprises the following steps: S1, pretreating the raw ash of the household garbage incineration fly ash, and then compounding and mixing the pretreated household garbage incineration fly ash with a compatible material to obtain a mixed material; melting at high temperature to obtain a slag glass body; s2, compounding and mixing the slag glass body and industrial solid waste, and then performing high-temperature calcination to obtain a high-temperature sintered body; s3, grinding and screening the high-temperature sintered body to obtain a sintered body mixture; s4, mixing the sintered body mixture with an alkali activator and water to obtain mixed slurry; and S5, pouring the mixed slurry into a mold, and carrying out molding, maintenance and demolding to obtain the geopolymer. The geopolymer prepared by the method disclosed by the invention has relatively high strength and good anti-permeability and corrosion resistance, can be widely applied to the fields of buildings, road engineering and the like, and realizes harmless treatment and resource utilization of fly ash and high-added-value resource utilization of industrial solid wastes at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste treatment and resource utilization, and in particular to a method for preparing geopolymers by combining fly ash from domestic waste incineration with industrial solid waste. Background Art

[0002] Fly ash from the incineration of municipal solid waste is a by-product of the incineration process. It contains harmful substances such as heavy metals and dioxins. If not handled properly, it will pose a serious threat to the environment and human health. At present, the harmless disposal of fly ash mostly adopts the method of solidification first and then landfill. Among them, cement solidification is a more commonly used solidification / stabilization method, which has a better solidification effect compared with traditional methods such as lime solidification. However, fly ash from the incineration of municipal solid waste contains a large amount of soluble substances. Direct cement solidification not only increases the volume significantly, but may also affect the performance of the solidified body as a building material due to the high CaO content and low SiO2 and Al2O3 content in the fly ash. In addition, the solidification / stabilization method has disadvantages such as low solidified body strength and poor stabilization effect on heavy metals. It is difficult to fundamentally solve the environmental pollution risks of fly ash, and it also occupies a large amount of land resources.

[0003] Industrial solid waste refers to solid waste generated during industrial production activities, such as steel slag, slag, fly ash, etc. Large-scale storage not only occupies land resources, but also poses a risk of environmental pollution. Traditional disposal methods are mostly simple landfill or low-value-added building materials production, with low resource utilization. Summary of the Invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method for preparing geopolymers by combining fly ash from the incineration of domestic waste with industrial solid waste. This method can not only achieve the harmless treatment and high-value-added resource utilization of fly ash from the incineration of domestic waste and industrial solid waste, but also the prepared geopolymer has high strength, good impermeability and corrosion resistance, and can be widely used in construction, road engineering and other fields.

[0005] To achieve the above objectives, the technical solution of the present invention is a method for preparing geopolymers by using fly ash from the incineration of domestic waste and industrial solid waste, comprising the following steps:

[0006] S1. Pre-treating the raw fly ash from the incineration of domestic waste, then compounding and mixing the pre-treated fly ash with a matching material, and then melting the mixture at a high temperature to obtain a slag glass body;

[0007] S2, mixing the slag glass body with industrial solid waste, and then calcining it at high temperature to obtain a high-temperature sintered body;

[0008] S3, grinding and screening the high-temperature sintered body to obtain a sintered body mixture;

[0009] S4, mixing the sintered body mixture with an alkali activator and water to obtain a mixed slurry;

[0010] S5. Pour the mixed slurry into a mold, and obtain the geopolymer after molding, curing, and demoulding.

[0011] As one of the embodiments, in step S2, when the slag glass body and industrial solid waste are compounded and mixed, the total amount of the slag glass body and the industrial solid waste is 100 wt.%, of which the slag glass body accounts for 20-80 wt.%, and the industrial solid waste accounts for 20-80 wt.%.

[0012] As one embodiment, in step S2, the slag glass body is compounded and mixed with industrial solid waste, and then crushed and ground to a particle size of 300 to 500 m² / kg, and then calcined at high temperature.

[0013] As one embodiment, in step S2, the high-temperature calcination temperature is 900-1200°C, and the holding time is 30-90 minutes.

[0014] As one of the implementation modes, in step S3, the particle size of the sintered body mixture is ≤5 mm.

[0015] As one of the embodiments, in step S4, the amount of the alkali activator used is 10-20 wt.% of the total amount of the sintered body mixture.

[0016] As one of the implementation methods, in step S5, after the mixed slurry is poured into the mold, it is first vibrated on a vibration table for 1 to 3 minutes and then allowed to stand for molding; curing is to place the molded geopolymer blocks into a curing box and cure them at room temperature.

[0017] As one embodiment, in step S1, the method for pre-treating the fly ash from the incineration of domestic waste is as follows:

[0018] S11, drying the raw fly ash from the incineration of domestic waste, and then grinding and screening it to obtain the raw material of the fly ash from the incineration of domestic waste;

[0019] S12, performing three-stage countercurrent filter pressing and water washing on the fly ash raw material from the incineration of domestic waste to obtain filter cake fly ash;

[0020] S13, drying the filter cake fly ash to obtain pre-treated domestic waste incineration fly ash.

[0021] As one of the implementation methods, in step S1, when the pretreated domestic waste incineration fly ash is compounded and mixed with the matching materials, the total amount of the pretreated domestic waste incineration fly ash and the matching materials is 100 wt.%, of which the pretreated domestic waste incineration fly ash accounts for 30-60 wt.%, and the matching materials account for 40-70 wt.%.

[0022] As one embodiment, in step S1, the high-temperature melting temperature is 1200-1500° C., and the holding time is 30-180 min.

[0023] The principles of the present invention are as follows:

[0024] The present invention removes most of the salt and part of the heavy metals in the fly ash from the incineration of domestic waste through pretreatment, and then mixes the pretreated fly ash from the incineration of domestic waste with the matching materials and melts them at high temperature, so that the dioxins in the fly ash are completely decomposed after high-temperature melting, and the residual heavy metals and chloride salts are solidified in the slag glass, which significantly reduces the toxicity of the fly ash. The obtained slag glass has high SiO2 and Al2O3 contents. After being mixed with industrial solid waste and calcined at high temperature, the slag glass and the industrial solid waste undergo solid-phase sintering reaction, and the particles react through diffusion, grain boundary movement and other processes to form a dense high-temperature sintered body, thereby improving the mechanical properties and stability of the material. At the same time, the crystalline phase in the industrial solid waste releases active silicon and aluminum during high-temperature calcination, and reacts with the solid-phase sintered body. The components of the slag glass body complement each other, optimize the calcium-silicon ratio of the system, and form new salt minerals such as calcium silicate, which can promote the geopolymer reaction and improve the strength of the geopolymer; the high-temperature sintered body is then ground and sieved to obtain a sintered body mixture, and the sintered body mixture is activated using an alkali activator. During the high-temperature sintering process, SiO2 and Al2O3 in the slag glass body are partially crystallized again, and the crystalline silicate minerals in the industrial solid waste are decomposed, so that SiO2 and Al2O3 exist in a more active amorphous form, and the specific surface area is increased. Under the action of the alkali activator, the rate of silicon-aluminum polymerization reaction is accelerated, and the gel generated by the reaction uses silicon-oxygen tetrahedron (SiO4) and aluminum-oxygen tetrahedron (AlO4) as the basic structural units to form a three-dimensional polymerization network by sharing oxygen atoms, Ca 2+ It fills the network gaps to enhance structural stability, and the formed geopolymer has a dense flocculent or honeycomb structure with low porosity (<10%).

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention completely decomposes organic pollutants such as dioxins in fly ash by high-temperature melting, and vitrifies the fly ash under high-temperature conditions by adding a compatibility material. The degree of harmlessness is extremely high, the heavy metal solidification effect is good, and the obtained slag glass can be used as a raw material for building materials, thereby achieving safe disposal and resource utilization of fly ash;

[0027] (2) The present invention mixes slag glass with high SiO2 and Al2O3 contents with industrial solid waste, and then calcines it at high temperature to form a dense high-temperature sintered body. At the same time, new salt minerals such as calcium silicate are formed, which can improve the formation reaction rate and strength of the geopolymer. After grinding and screening, it is activated by an alkaline activator. The formed geopolymer has a dense flocculent or honeycomb structure and low porosity.

[0028] (3) The geopolymer prepared by the method of the present invention has high strength, with a 28-day compressive strength of 50-60 MPa, and good properties such as impermeability and corrosion resistance, and can be widely used in the fields of construction, road engineering, etc.

[0029] (4) The present invention uses fly ash from the incineration of domestic waste and industrial solid waste in a synergistic manner to prepare geopolymers, achieving harmless treatment and resource utilization of fly ash and high-value-added resource utilization of industrial solid waste, reducing dependence on natural resources and reducing the stockpile of industrial solid waste;

[0030] (5) The present invention utilizes fly ash from the incineration of domestic waste and industrial solid waste as the main raw materials, which reduces the production cost of geopolymers and improves economic benefits. Moreover, the entire preparation process does not generate secondary pollution, meets the requirements of sustainable development, and has good environmental and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 This is a flow chart of a method for preparing geopolymers by combining fly ash from incineration of domestic waste with industrial solid waste provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] The embodiment of the present invention provides a method for preparing geopolymers by using fly ash from domestic waste incineration and industrial solid waste, comprising the following steps:

[0035] S1. Pre-treating the raw fly ash from the incineration of domestic waste, then compounding and mixing the pre-treated fly ash with a matching material, and then melting the mixture at a high temperature to obtain a slag glass body;

[0036] S2, mixing the slag glass body with industrial solid waste, and then calcining it at high temperature to obtain a high-temperature sintered body;

[0037] S3, grinding and screening the high-temperature sintered body to obtain a sintered body mixture;

[0038] S4, mixing the sintered body mixture with an alkali activator and water to obtain a mixed slurry;

[0039] S5. Pour the mixed slurry into a mold, and obtain the geopolymer after molding, curing, and demoulding.

[0040] In this embodiment, the pre-treated domestic waste incineration fly ash is mixed with the matching materials and then melted at high temperature, so that the dioxins in the fly ash are completely decomposed after high-temperature melting, and the residual heavy metals and chloride salts are solidified in the slag glass, which significantly reduces the toxicity of the fly ash. The SiO2 and Al2O3 contents of the obtained slag glass are high, and the acidity coefficient is about 1.6~2.0, which meets the compliance level for the disposal of fly ash solid waste; after the slag glass with high SiO2 and Al2O3 contents is mixed with industrial solid waste, it is calcined at high temperature, and the slag glass and the industrial solid waste undergo solid-phase sintering reaction, and the particles are bonded together by The high-temperature sintered body reacts through processes such as diffusion and grain boundary movement to form a dense high-temperature sintered body, thereby improving the mechanical properties and thermal stability of the material. At the same time, new salt minerals such as calcium silicate are formed, which can promote the geopolymer reaction and improve the strength of the geopolymer. The high-temperature sintered body is then ground and sieved to obtain a sintered body mixture, which is activated by an alkali activator. The SiO2 and Al2O3 in the material react rapidly under the action of the alkali activator. The gel generated by the reaction uses silicon oxide tetrahedron (SiO4) and aluminum oxide tetrahedron (AlO4) as basic structural units to form a three-dimensional polymer network by sharing oxygen atoms. Ca 2+ It fills the gaps in the network to enhance structural stability, and the formed geopolymer is dense flocculent or honeycomb-like with low porosity (<10%), high strength, and good impermeability and corrosion resistance. It can be widely used in construction, road engineering and other fields. At the same time, it fundamentally solves the environmental pollution risks of fly ash, realizes the high added value utilization of industrial solid waste, and improves resource utilization efficiency.

[0041] Furthermore, in step S2, when the slag glass body and industrial solid waste are compounded and mixed, the total amount of the slag glass body and the industrial solid waste is 100 wt.%, of which the slag glass body accounts for 20 to 80 wt.%, and the industrial solid waste accounts for 20 to 80 wt.%.

[0042] The industrial solid waste is selected from the group consisting of bottom ash from municipal solid waste incinerators, slag, and fly ash. When fly ash is used as the industrial solid waste, the CaO content is relatively low. After high-temperature calcination with slag glass, grinding, screening, and alkali excitation, the resulting geopolymer is cured at room temperature to form a loose, flocculent structure with a compressive strength of 20-60 MPa, good toughness, and strong impact resistance, making it suitable for use as a buffer material. When the industrial solid waste is bottom ash or slag from municipal solid waste incinerators, the industrial solid waste is selected from the group consisting of bottom ash or slag from municipal solid waste incinerators, grinding, screening, and alkali excitation, and then cured at room temperature to form a honeycomb structure with a compressive strength of 10-30 MPa, good thermal conductivity, and suitable for use as a thermal insulation material.

[0043] Furthermore, in step S2, the slag glass and industrial solid waste are mixed and then crushed and ground to a particle size of 300 to 500 m² / kg, followed by high-temperature calcination. In this embodiment, the slag glass and industrial solid waste mixture is crushed and ground to a particle size of 300 to 500 m² / kg before being subjected to high-temperature calcination, which significantly increases the solid-phase reaction rate during calcination.

[0044] Furthermore, in step S2, the high-temperature calcination temperature is 900-1200°C, and the holding time is 30-90 minutes. Preferably, the high-temperature calcination temperature is 1000°C, and the holding time is 60 minutes. By controlling the temperature and time of the high-temperature calcination, it is ensured that the slag glass body and the industrial solid waste fully undergo solid-phase sintering reaction, forming a dense high-temperature sintered body and simultaneously forming new salt minerals such as calcium silicate;

[0045] Furthermore, in step S3, the particle size of the sintered body mixture is ≤5 mm. This embodiment grinds and screens the high-temperature sintered body obtained by high-temperature calcination of slag glass and industrial solid waste to ensure the uniformity of the geopolymer raw materials and controls the particle size of the sintered body mixture to ≤5 mm. This increases the specific surface area of ​​the sintered body mixture, ensures sufficient contact between the sintered body mixture and the alkaline activator, promotes the reaction between the alkaline activator and the active components, and improves the mechanical properties of the geopolymer.

[0046] Furthermore, in step S4, the amount of the alkaline activator used is 10-20 wt.% of the total amount of the sintered body mixture. Since the slag glass body is compounded with industrial solid waste and then calcined at high temperature, and then ground and screened to obtain the sintered body mixture, the content of SiO2 and Al2O3 is high and the number of active sites is large. Therefore, the amount of alkaline activator used during geopolymer activation can be significantly reduced, which is conducive to reducing production costs.

[0047] In this example, the alkaline activator is prepared by adjusting the modulus of water glass with sodium hydroxide. The concentration of sodium hydroxide is 8 to 12 mol / L, and the mass ratio of sodium hydroxide to water glass is 1:1 to 5:1. The addition of NaOH during the preparation of the alkaline activator solution will cause the solution to release heat. Therefore, the solution must be stirred thoroughly and sealed with plastic film to retain moisture. The solution should be cooled to room temperature before use.

[0048] Furthermore, in step S5, after the mixed slurry is poured into the mold, it is first vibrated on a vibration table for 1 to 3 minutes and then allowed to stand for molding; curing is to place the formed geopolymer blocks into a curing box and cure them at room temperature. In this embodiment, the mixed slurry is poured into the mold for an activation reaction, and at the initial stage of the activation reaction when the slurry has high fluidity, it is vibrated on a vibration table for 1 to 3 minutes to expel any bubbles that may be present in the mixture and prevent the formation of honeycomb pores after later solidification. Vibration can also make the geopolymer formed later more dense and improve its overall performance. In addition, since the high activity of the sintered body mixture can accelerate the polymerization reaction of the geopolymer, the geopolymer of this embodiment only needs to be cured at room temperature, without the need for complex methods such as high-temperature curing or water curing. This not only simplifies the curing process, but also reduces curing costs, while also helping to reduce energy consumption and environmental pollution.

[0049] Furthermore, in step S1, the method for pre-treating the fly ash from the incineration of domestic waste is as follows:

[0050] S11, drying the raw fly ash from the incineration of domestic waste, and then grinding and screening it to obtain the raw material of the fly ash from the incineration of domestic waste;

[0051] S12, performing three-stage countercurrent filter pressing and water washing on the fly ash raw material from the incineration of domestic waste to obtain filter cake fly ash;

[0052] S13, drying the filter cake fly ash to obtain pre-treated domestic waste incineration fly ash.

[0053] This embodiment performs three-stage countercurrent filter pressing and water washing on the fly ash from the incineration of domestic waste, thereby washing out most of the salt and some heavy metals and other soluble pollutants in the fly ash. This not only reduces the impact of waste salt and heavy metals on the subsequent high-temperature melting process, prevents coking and corrosion of the smelting furnace and flue gas treatment system during high-temperature melting treatment, but also reduces the moisture content of the fly ash filter cake and improves the washing effect. The process is simple, low-cost, and has a significant reduction effect. It can also be flexibly combined with other processes.

[0054] In step S11, the raw ash of the domestic waste incineration fly ash is dried in an oven at 105°C for 12 to 24 hours to remove moisture from the raw ash; the raw ash is sieving through a 50-100 mesh sieve to ensure that the particle size of the fly ash mostly reaches 50-100 mesh to ensure the uniformity of the fly ash, which is beneficial to the subsequent fly ash compatibility and high-temperature melting.

[0055] In step S12, the domestic waste incineration fly ash raw material is subjected to three-stage countercurrent filter pressing and water washing, which is to send the domestic waste incineration fly ash raw material into a three-stage countercurrent water washing equipment, and the solid-liquid ratio is set to 1:3, and filter cake fly ash is obtained after the filter pressing is completed.

[0056] In step S13, the filter cake fly ash is dried in an oven at 105° C. for 12 to 24 hours.

[0057] Furthermore, in step S1, when the pretreated municipal solid waste incineration fly ash is compounded and mixed with the accompanying materials, the total amount of the pretreated municipal solid waste incineration fly ash and the accompanying materials is 100 wt.%, of which the pretreated municipal solid waste incineration fly ash accounts for 30-60 wt.% and the accompanying materials account for 40-70 wt.%. In this embodiment, the accompanying materials are proportionally compounded based on the acidity coefficient calculation, and the pretreated municipal solid waste incineration fly ash and the accompanying materials are combined in a specific ratio to ensure that the composition of the high-temperature molten product slag glass is stable and non-toxic. In this embodiment, the accompanying material is at least one of silica, basalt, granite, and waste glass.

[0058] Furthermore, in step S1, the high-temperature melting temperature is 1200-1500°C, and the holding time is 30-180 minutes. The high-temperature environment during the high-temperature melting process can completely decompose organic pollutants such as dioxins. The addition of compatibility materials vitrifies the fly ash, stabilizing heavy metals in the slag glass. The resulting slag glass has a heavy metal content that meets relevant standards, and the process is highly adaptable and has controllable environmental risks.

[0059] The method of the present invention is described in detail below through specific examples.

[0060] Example 1: A method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste, comprising the following steps:

[0061] 1) Take a certain amount of domestic waste incineration fly ash, dry it at 105℃, grind it into powder, and pass it through a 100-mesh sieve to obtain domestic waste incineration fly ash raw material;

[0062] 2) The fly ash from the incineration of domestic waste is subjected to three-stage countercurrent filter pressing and water washing, with the solid-liquid ratio set at 1:3. After the filter pressing, filter cake fly ash is obtained;

[0063] 3) Drying the filter cake fly ash to obtain pre-treated domestic waste incineration fly ash;

[0064] 4) 60 wt.% pretreated municipal solid waste incineration fly ash, 30 wt.% basalt, and 10 wt.% silica were mixed and melted in a high-temperature furnace at 1400°C for 120 minutes to obtain a slag glass;

[0065] 5) 20 wt.% slag glass is mixed with 80 wt.% fly ash, crushed and ground to a particle size of 300-500 m² / kg, and then calcined at 1000°C for 60 minutes to obtain a high-temperature sintered body;

[0066] 6) Grinding and sieving the high-temperature sintered body to obtain a sintered body mixture with a particle size of ≤5 mm;

[0067] 7) adding 10 wt.% of an alkaline activator to the sintered body mixture, wherein the alkaline activator is a mixture of sodium hydroxide and water glass in a ratio of 1:3 to obtain a mixed slurry;

[0068] 8) Pour the mixed slurry into the mold for activation reaction for 30 minutes, then place it in a curing box and cure it at room temperature for 30 hours. De-mold it to obtain the geopolymer.

[0069] Comparative Example 1: A method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste, comprising the following steps:

[0070] 1) Take a certain amount of domestic waste incineration fly ash, dry it at 105℃, grind it into powder, and pass it through a 100-mesh sieve to obtain domestic waste incineration fly ash raw material;

[0071] 2) The fly ash from the incineration of domestic waste is subjected to three-stage countercurrent filter pressing and water washing, with the solid-liquid ratio set at 1:3. After the filter pressing, filter cake fly ash is obtained;

[0072] 3) Drying the filter cake fly ash to obtain pre-treated domestic waste incineration fly ash;

[0073] 4) 60 wt.% pretreated municipal solid waste incineration fly ash, 30 wt.% basalt, and 10 wt.% silica were mixed and melted in a high-temperature furnace at 1400°C for 120 minutes to obtain a slag glass;

[0074] 5) 20 wt.% slag glass and 80 wt.% fly ash are mixed, ground, and sieved to obtain a mixture with a particle size of ≤5 mm;

[0075] 6) adding 10 wt.% of an alkaline activator to the mixture, wherein the alkaline activator is a mixture of sodium hydroxide and water glass in a ratio of 1:3, to obtain a mixed slurry;

[0076] 7) Pour the mixed slurry into the mold for activation reaction for 30 minutes, place it in a curing box, and cure it at room temperature for 50 hours. Demold it to obtain the geopolymer.

[0077] The raw materials used in Comparative Example 1 are the same as those in Example 1, and the curing conditions are the same.

[0078] Among them, the mass percentages of the main components of the fly ash from the incineration of domestic waste are: SiO2 4.18%, CaO42.96%, Al2O31.41%, MgO 1.36%, Na2O 10.49%, K2O 5.02%, Cl 20.04%;

[0079] The mass percentages of the main components of the slag glass are: SiO2 45.53%, Al2O3 12.38%, CaO21.31%, and MgO 1.17%.

[0080] The compressive strength of the geopolymers obtained in Example 1 and Comparative Example 1 was tested. The 5-day compressive strength of the geopolymer in Example 1 was 25.9 MPa, and the 28-day compressive strength reached 58.2 MPa. The 5-day compressive strength of the geopolymer in Comparative Example 1 was 16.3 MPa, and the 28-day compressive strength reached 41.1 MPa. This indicates that the method of the present invention significantly accelerates the reaction rate, shortens the geopolymer setting time, and significantly improves the strength of the geopolymer.

[0081] 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, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing geopolymers by using fly ash from domestic waste incineration and industrial solid waste, characterized in that: The steps include: S1. Pre-treating the raw fly ash from the incineration of domestic waste, then compounding and mixing the pre-treated fly ash with a matching material, and then melting the mixture at a high temperature to obtain a slag glass body; S2, mixing the slag glass body with industrial solid waste, and then calcining it at high temperature to obtain a high-temperature sintered body; S3, grinding and screening the high-temperature sintered body to obtain a sintered body mixture; S4, mixing the sintered body mixture with an alkali activator and water to obtain a mixed slurry; S5. Pour the mixed slurry into a mold, and obtain the geopolymer after molding, curing, and demoulding.

2. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S2, when the slag glass body and the industrial solid waste are compounded and mixed, the total amount of the slag glass body and the industrial solid waste is 100 wt.%, of which the slag glass body accounts for 20 to 80 wt.%, and the industrial solid waste accounts for 20 to 80 wt.%.

3. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S2, the slag glass body is compounded and mixed with industrial solid waste, and then crushed and ground to a particle size of 300 to 500 m² / kg, and then calcined at high temperature.

4. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S2, the high-temperature calcination temperature is 900-1200°C, and the holding time is 30-90 minutes.

5. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S3, the particle size of the sintered body mixture is ≤5 mm.

6. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S4, the amount of the alkali activator used is 10-20 wt.% of the total amount of the sintered body mixture.

7. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S5, after the mixed slurry is poured into the mold, it is first vibrated on a vibration table for 1 to 3 minutes and then allowed to stand for molding; curing is to place the molded geopolymer blocks into a curing box and cure them at room temperature.

8. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S1, the method for pre-treating the fly ash from the incineration of domestic waste is as follows: S11, drying the raw fly ash from the incineration of domestic waste, and then grinding and screening it to obtain the raw material of the fly ash from the incineration of domestic waste; S12, performing three-stage countercurrent filter pressing and water washing on the fly ash raw material from the incineration of domestic waste to obtain filter cake fly ash; S13, drying the filter cake fly ash to obtain pre-treated domestic waste incineration fly ash.

9. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S1, when the pretreated domestic waste incineration fly ash is compounded and mixed with the matching materials, the total amount of the pretreated domestic waste incineration fly ash and the matching materials is 100 wt.%, of which the pretreated domestic waste incineration fly ash accounts for 30-60 wt.%, and the matching materials account for 40-70 wt.%.

10. The method for preparing geopolymers from fly ash from domestic waste incineration and industrial solid waste as claimed in claim 1, characterized in that: In step S1, the high-temperature melting temperature is 1200-1500° C., and the holding time is 30-180 min.

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