Device and method for preparing fly ash vitrified composite material through thermocompression coupling based on CaO-Al2O3-SiO2 three-phase proportion adjustment

Abstract

The invention discloses a device and a method for preparing a fly ash vitrified composite material through thermocompression coupling based on CaO-Al2O3-SiO2 three-phase proportion adjustment, and belongs to the field of resource utilization of bulk industrial solid wastes. The preparation method comprises the following steps: screening a proportion range of CaO-Al2O3-SiO2 three-phase substances based on Factsage, uniformly mixing high-silicon materials from three different sources and fly ash according to a certain proportion within the proportion range, then carrying out high-pressure clustering treatment to improve the contact area and the densification degree among particles, uniformly paving a block mass in a refractory mold, and carrying out non-crystallization high-temperature heat treatment, so as to obtain the high-silicon composite material. And cutting, grinding and polishing the crude product subjected to heat treatment to obtain the vitrified composite material. The amorphous glass composite material is prepared from fly ash and industrial wastes or cheap industrial raw materials, the production process is simple, the requirement on the treatment atmosphere is avoided, the industrial energy consumption and the product cost are greatly reduced, and the product has excellent heavy metal leaching prevention performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of resource utilization of bulk industrial solid waste, and specifically relates to a device and method for preparing composite materials by vitrification of fly ash based on hot-pressing coupling with adjustment of the three-phase ratio of CaO-Al2O3-SiO2. Background Art

[0002] Fly ash is the fine particles in the flue gas produced during the incineration of hazardous waste or garbage. Because it contains high levels of dioxins, heavy metals and chlorides, it is defined as hazardous waste by various countries.

[0003] There are three hot treatment methods at present: solidification / stabilization, hydrometallurgical extraction and separation, and thermal treatment. Solidification / stabilization uses cement and chemical stabilizers to fix harmful substances. However, the hydration reaction activity of fly ash is low, which will delay the cement hydration process to a certain extent and significantly reduce the strength of cement mortar. In addition, solidification and stabilization have poor fixation effects on certain heavy metal elements and toxic persistent organic pollutants (POPs) in fly ash. Extraction and separation use chemical solvents or biological leaching of low-grade heavy metals in fly ash to achieve the purpose of resource recovery, but the use of strong acids and alkalis will cause environmental risks. At the same time, the leached ash will still release a large amount of heavy metals during the toxicity characteristic leaching procedure (TCLP), which still poses environmental risks. Thermal treatment includes sintering and melt vitrification. The former is treated at a lower heat treatment temperature to form a sintered body that meets the performance requirements, and the latter forms a glassy substance at high temperature, which encapsulates heavy metals and degrades toxic organic matter. Sintering may lead to dioxin resynthesis, which poses a certain risk. Vitrification is considered to be a promising treatment method because of its good fixation of heavy metals, high removal rate of dioxins and high added value of products.

[0004] At present, the method for preparing glass from fly ash is mainly to melt the fly ash without or with the addition of industrial raw materials, such as boric oxide. There are problems such as high melting temperature, high energy consumption, and expensive industrial raw materials such as boric oxide. The prepared glass product has many voids and a high heavy metal leaching rate. Summary of the invention

[0005] The purpose of the present invention is to provide a device and method for preparing fly ash vitrified composite materials based on hot-pressing coupling adjustment of the three-phase ratio of CaO-Al2O3-SiO2, aiming to overcome the problems of the existing method of using fly ash to prepare amorphous glass composite materials, such as the need to add expensive additives and other chemical raw materials, and reduce the required fusion temperature to about 1190°C, which can increase the content of glassy substances, reduce the product volume, and improve product performance.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] A method for preparing fly ash vitrified composite material based on hot-pressing coupling by adjusting the ratio of three phases of CaO-Al2O3-SiO2 comprises the following steps:

[0009] Step 1: Composition analysis of raw materials: Analyze the composition of fly ash, waste glass powder, silica sand and plant ash respectively;

[0010] Step 2: Based on the FToxid database of Factsage, the liquidus projection diagram of the CaO, Al2O3, SiO2 ternary system is calculated in the Equilib module to obtain the melting temperatures of mixed substances of CaO, Al2O3, SiO2 with different proportions; according to the melting temperatures of different proportions, the three-phase material ratio range with a melting temperature below 1200°C is further divided into CaO:Al2O3:SiO2=20~30:1~12:30~45. The ratio within the three-phase material ratio range is selected to deduce the mixing ratio of fly ash and other raw materials.

[0011] Step 3: Preparation of raw materials: crushing and screening fly ash, waste glass powder, silica sand and plant ash respectively;

[0012] Step 4: Mix the fly ash with any one or more of waste glass powder, silica sand and plant ash;

[0013] Step 5, pressing the mixture of step 4 into a shape;

[0014] Step 6, melting the pressed mixture at high temperature, annealing, and program cooling to obtain the amorphous glass crude product;

[0015] Step 7: Cut, beat and polish the rough amorphous glass product to obtain an amorphous glass composite material product.

[0016] Furthermore, the particle size of the fly ash is not greater than 150 μm, and the three-phase ratio of the fly ash CaO-Al2O3-SiO2 is CaO:Al2O3:SiO2=30~50:0~15:0~10; the particle size of the waste glass powder is not greater than 150 μm, and the three-phase ratio of the waste glass powder CaO-Al2O3-SiO2 is CaO:Al2O3:SiO2=0~10:0~20:5 0~80; the particle size of the silica sand is not more than 150μm, and the three-phase ratio of the silica sand CaO-Al2O3-SiO2 is CaO:Al2O3:SiO2=0~5:0~5:85~98; the particle size of the wood ash is not more than 150μm, and the three-phase ratio of the wood ash CaO-Al2O3-SiO2 is CaO:Al2O3:SiO2=0~10:10~30:40~70.

[0017] Furthermore, when fly ash is mixed with waste glass powder, the mixed mass ratio is 57:43 to 40:60; when fly ash is mixed with silica sand, the mixed mass ratio is 65:35 to 60:40; when fly ash is mixed with wood ash, the mixed mass ratio is 50:50 to 25:75.

[0018] Furthermore, the pressing pressure is 10-20 MPa, and the pressing time is 100-200 s.

[0019] Furthermore, experiments were carried out in a high-temperature tube furnace with a melting temperature of 1100°C to 1400°C, a heating rate of 10°C to 25°C / min below 1000°C, and 5°C to 10°C / min between 1000°C and 1400°C. After reaching the specified temperature, the temperature was kept for 30min to 120min, and the cooling rate was 10°C to 20°C / min. The formed mass was placed in a corundum crucible.

[0020] The present invention also provides an amorphous glass composite material product, which is prepared by the above-mentioned preparation method.

[0021] The present invention also provides a device for preparing fly ash vitrified composite material by hot-pressing coupling based on adjusting the three-phase ratio of CaO-Al2O3-SiO2, comprising a crushing and screening device, a premixing and drying device, a molding and processing device, a melting and vitrification device, and a grinding and molding device;

[0022] The crushing and screening device, premixing and drying device, molding and processing device, and molten vitrification device are connected in sequence. The secondary fly ash outlet of the molten vitrification device is connected to a recovery device for replenishing raw fly ash; the molten product outlet of the molten vitrification device is connected to a grinding and molding device.

[0023] Beneficial effects of the present invention:

[0024] The method for preparing an amorphous glass composite material product provided by the present invention uses solid waste materials and cheap industrial raw materials, and the method shows good adaptability to materials of different components in the process. On the premise that the glass product meets the industry standards, the amount of fly ash added reaches 50%. At the same time, after the ash melting point test, the lowest melting temperature of the mixed raw materials can be controlled at about 1190°C, which greatly reduces the energy consumption of the production process.

[0025] The present invention mixes fly ash with additives and performs vitrification through heat-pressure coupling synergistic treatment. The application of high pressure gradually increases the filling degree of the system, strengthens the migration and diffusion rate of molecules and atoms in the fly ash mixture, strengthens the contact between molecules, reduces the porosity of the system, and heats on this basis, which ultimately manifests itself macroscopically as an increase in the density of the vitrified melt product.

[0026] Finally, after testing and research, it was found that the prepared glass also has a low heavy metal leaching rate and a low secondary fly ash generation rate, and the product performance is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a schematic diagram of the process of preparing fly ash vitrified composite materials by hot-pressing coupling based on adjusting the ratio of the three phases of CaO-Al2O3-SiO2.

[0028] Figure 2 It is the liquid surface projection diagram calculated by Factsage of the present invention.

[0029] Figure 3 It is a comparison chart of XRD and amorphous component content between the experimental example of the present invention and the comparative example. DETAILED DESCRIPTION

[0030] The following is a further description of the specific implementation of the present invention in combination with the technical solution:

[0031] The components of fly ash, waste glass powder, silica sand and wood ash were analyzed respectively. Then, based on the FToxid database of Factsage, the liquidus surface projection diagram of the CaO, Al2O3 and SiO2 ternary system was calculated in the Equilib module to obtain the melting temperatures of mixed substances of CaO, Al2O3 and SiO2 with different proportions. According to the melting temperatures of different proportions, the three-phase material ratio range with a melting temperature below 1200°C is further divided, which is CaO:Al2O3:SiO2=20~30:1~12:30~45. Three point values ​​within the range of melting temperature below 1200°C are selected, and according to the three-phase component ratio of the point values, the mixing ratio of fly ash and additives is calculated respectively using the components of fly ash and additives, which is the embodiment in the experiment. The specific embodiment is as follows:

[0032] Example 1

[0033] (1) The main chemical compositions of fly ash are CaO 45.1%, Cl 13.6%, Na2O 8.1%, CdO 8.9%, SO3 7.8%, ZnO 5.9%, K2O 1.6%, SiO2 1.5%, MgO 1.0%, Al2O3 0.5% and some trace substances; the main chemical compositions of waste glass powder are SiO2 68.8%, Na2O 16.5%, CaO 8.3%, MgO 4.0%, Al2O3 1.0% and some trace substances.

[0034] (2) The ratio of fly ash to waste glass powder is 43:57, with a total of 5g sample. Weigh 2.15g of fly ash sample, crush, dry, grind and screen, and the particle size is less than 150μm; weigh 2.85g of waste glass powder, crush, dry, grind and screen, and the particle size is less than 150μm, and then mix them. The chemical composition of the mixed sample is SiO2 39.89%, CaO24.47%, Na2O14.32%, Cl 5.98%, CdO 3.91%, SO3 3.55%, ZnO 2.57%, MgO 2.70%, K2O2.10%, Al2O3 1.95% and some trace substances.

[0035] 5 g of the mixed material was placed in a compression mold with a cavity inner diameter of 20 mm and subjected to briquetting treatment at a pressure of 15 MPa for 180 s on a universal testing machine;

[0036] The pretreated sample was placed in a corundum crucible and treated in a tubular resistance melting furnace at 1400°C for 2.0 hours. The resulting slag was naturally cooled in the air and analyzed after crushing and grinding. The heating rate of the tubular furnace was 10°C / min below 1000°C and 5°C / min between 1000°C and 1400°C. The atmosphere was air.

[0037] The obtained amorphous glass composite material rough product is cut, ground and polished to obtain an amorphous glass composite material product.

[0038] Test results: The product prepared according to the above parameters has an amorphous degree of 97.8%. The XRD spectrum shows that it is completely amorphous and the density reaches 2.0g / cm 3The heavy metal leaching level also reached the allowable range of the specification. The leaching level of Cr was reduced to 0.15±0.04mg / L, the leaching level of Cu was reduced to 3.15±0.04mg / L, the leaching level of Zn was reduced to 78.80±5.1mg / L, the leaching level of Cd was reduced to 0.15±0.04mg / L, and the leaching level of Pb was reduced to 0.2±0.02mg / L, which fully met the requirements of amorphous glass composite materials products.

[0039] Comparative Example 1

[0040] (1) The main chemical compositions of fly ash are CaO 45.1%, Cl 13.6%, Na2O 8.1%, CdO 8.9%, SO3 7.8%, ZnO 5.9%, K2O 1.6%, SiO2 1.5%, MgO 1.0%, Al2O3 0.5% and some trace substances; the main chemical compositions of waste glass powder are SiO2 68.8%, Na2O 16.5%, CaO 8.3%, MgO 4.0%, Al2O3 1.0% and some trace substances.

[0041] (2) The ratio of fly ash to waste glass powder is 70:30, with a total of 5g sample. Weigh 3.50g of fly ash sample, crush, dry, grind, and screen to a particle size of less than 150μm; weigh 1.50g of waste glass powder, crush, dry, grind, and screen to a particle size of less than 150μm, and then mix them. The chemical composition of the mixed sample is CaO 34.06%, SiO2 21.70%, Na2O 12.79%, Cl 9.53%, CdO 6.25%, ZnO 4.10%, SO3 3.55%, MgO 1.89%, K2O 1.24%, Al2O3 0.89% and some trace substances.

[0042] 5 g of the mixed material was placed in a compression mold with a cavity inner diameter of 20 mm and subjected to briquetting treatment at a pressure of 15 MPa for 180 s on a universal testing machine;

[0043] The pretreated sample was placed in a corundum crucible and treated in a tubular resistance melting furnace at 1400°C for 2.0 hours. The resulting slag was naturally cooled in the air and analyzed after crushing and grinding. The heating rate of the tubular furnace was 10°C / min below 1000°C and 5°C / min between 1000°C and 1400°C. The atmosphere was air.

[0044] The obtained rough product is cut, ground and polished to obtain the obtained product.

[0045] Test results: The product prepared according to the above parameters has an amorphization degree of 31.4%. The XRD spectrum shows that there are still many crystal diffraction peaks, and amorphization has not been achieved. The density is 1.6g / cm3 The heavy metal leaching levels are as follows: Cr leaching level is 0.33±0.02mg / L, Cu leaching level is 5.60±0.01mg / L, Zn leaching level is 100.4±1.20mg / L, Cd leaching level is 0.35±0.01mg / L, and Pb leaching level is 0.46±0.01mg / L. It does not meet the requirements of amorphous glass composite products.

[0046] Example 2

[0047] (1) The main chemical composition of fly ash is CaO 45.1%, Cl 13.6%, Na2O 8.1%, CdO8.9%, SO37.8%, ZnO 5.9%, K2O 1.6%, SiO21.5%, MgO 1.0%, Al2O30.5% and some trace substances; the main chemical composition of silica sand is SiO294.5%, Al2O3 3.8%, K2O 0.9%, CaO 0.1%;

[0048] (2) The ratio of fly ash to silica sand is 59:41, with a total of 5g sample. Weigh 2.95g of fly ash sample, crush, dry, grind, and screen, and the particle size is less than 150μm; weigh 2.05g of silica sand, crush, dry, grind, and screen, and the particle size is less than 150μm, and then mix. The chemical composition of the mixed sample is SiO2 39.64%, CaO 26.63%, Cl8.05%, Na2O 6.65%, CdO 5.27%, SO34.60%, ZnO 3.46%, Al2O3 1.84%, MgO 0.61%, K2O1.32%, and some trace substances.

[0049] 5 g of the mixed material was placed in a compression mold with a cavity inner diameter of 20 mm and subjected to briquetting treatment at a pressure of 15 MPa for 180 s on a universal testing machine;

[0050] The pretreated sample was placed in a corundum crucible and treated in a tubular resistance melting furnace at 1400°C for 2.0 hours. The resulting slag was naturally cooled in the air and analyzed after crushing and grinding. The heating rate of the tubular furnace was 10°C / min below 1000°C and 5°C / min between 1000°C and 1400°C. The atmosphere was air.

[0051] The obtained amorphous glass composite material rough product is cut, ground and polished to obtain an amorphous glass composite material product.

[0052] Test results: The product prepared according to the above parameters has an amorphous degree of 98.6%. The XRD spectrum shows that it is completely amorphous and the density reaches 2.5g / cm 3The heavy metal leaching level also reaches the allowable range of the specification, with the leaching level of Cr reduced to 0.19±0.01mg / L, the leaching level of Cu reduced to 1.37±0.04mg / L, the leaching level of Zn reduced to 17.44±1.2mg / L, the leaching level of Cd reduced to 0.02±0.01mg / L, and the leaching level of Pb reduced to 0.04±0.01mg / L. It fully meets the requirements of amorphous glass composite products.

[0053] Comparative Example 2

[0054] (1) The main chemical composition of fly ash is CaO 45.1%, Cl 13.6%, Na2O 8.1%, CdO8.9%, SO37.8%, ZnO 5.9%, K2O 1.6%, SiO21.5%, MgO 1.0%, Al2O30.5% and some trace substances; the main chemical composition of silica sand is SiO294.5%, Al2O3 3.8%, K2O 0.9%, CaO 0.1%;

[0055] (2) The ratio of fly ash to silica sand is 59:41, with a total of 5g sample. Weigh 2.95g of fly ash sample, crush, dry, grind, and screen, and the particle size is less than 150μm; weigh 2.05g of silica sand, crush, dry, grind, and screen, and the particle size is less than 150μm, and then mix. The chemical composition of the mixed sample is SiO2 39.64%, CaO 26.63%, Cl8.05%, Na2O 6.65%, CdO 5.27%, SO34.60%, ZnO 3.46%, Al2O3 1.84%, MgO 0.61%, K2O1.32%, and some trace substances.

[0056] 5g of the mixed material was placed in a corundum crucible and melted in a tubular resistance melting furnace at 1400℃ for 2.0h. The resulting slag was naturally cooled in the air and analyzed after crushing and grinding. The heating rate of the tubular furnace was 10℃ / min below 1000℃ and 5℃ / min between 1000℃ and 1400℃. The atmosphere was air.

[0057] The obtained rough product is cut, ground and polished to obtain the obtained product.

[0058] Test results: The product prepared according to the above parameters has an amorphization degree of 39.8%. The XRD spectrum shows that there are still many crystal diffraction peaks, and amorphization has not been achieved. The density is 1.8g / cm 3The heavy metal leaching levels are as follows: Cr leaching level is 0.35±0.02mg / L, Cu leaching level is 4.02±0.02mg / L, Zn leaching level is 95.32±1.2mg / L, Cd leaching level is 0.20±0.01mg / L, and Pb leaching level is 0.4±0.01mg / L. It does not meet the requirements of amorphous glass composite products.

[0059] Example 3

[0060] (1) The main chemical composition of fly ash is CaO 45.1%, Cl 13.6%, Na2O 8.1%, CdO8.9%, SO37.8%, ZnO 5.9%, K2O 1.6%, SiO21.5%, MgO 1.0%, Al2O30.5% and some trace substances; the main chemical composition of plant ash is SiO258.2%, Al2O316.8%, CaO 10.0%, Fe2O37.0%, SO32.0%, MgO1.9%;

[0061] (2) The ratio of fly ash to plant ash is 33:67, with a total of 5g sample. Weigh 1.65g of fly ash sample, crush, dry, grind, and screen to a particle size of less than 150μm, weigh 3.35g of plant ash, crush, dry, grind, and screen to a particle size of less than 150μm, and then mix. The chemical composition of the mixed sample is SiO2 39.49%, CaO 21.61%, Al2O3 11.41%, Cl 4.56%, Na2O4.36%, SO3 3.88%, CdO 2.94%, ZnO 1.94%, MgO1.60%, K2O 1.30%, and some trace substances.

[0062] 5 g of the mixed material was placed in a compression mold with a cavity inner diameter of 20 mm and subjected to briquetting treatment at a pressure of 15 MPa for 180 s on a universal testing machine;

[0063] The pretreated sample was placed in a corundum crucible and treated in a tubular resistance melting furnace at 1400°C for 2.0 hours. The resulting slag was naturally cooled in the air and analyzed after crushing and grinding. The heating rate of the tubular furnace was 10°C / min below 1000°C and 5°C / min between 1000°C and 1400°C. The atmosphere was air.

[0064] The obtained amorphous glass composite material rough product is cut, ground and polished to obtain an amorphous glass composite material product.

[0065] Test results: The product prepared according to the above parameters has an amorphous degree of 96.3%. The XRD spectrum shows that it is completely amorphous and the density reaches 2.2g / cm 3. The heavy metal leaching also reaches the allowable range of the specification, the leaching level of Cr is reduced to 0.27±0.02mg / L, the leaching level of Cu is reduced to 2.71±0.06mg / L, the leaching level of Zn is reduced to 62.38±6.9mg / L, the leaching level of Cd is reduced to 0.07±0.02mg / L, and the leaching level of Pb is reduced to 0.03±0.01mg / L. The requirements of fully amorphous glass composite products.

[0066] Comparative Example 3

[0067] (1) The main chemical composition of fly ash is CaO 45.1%, Cl 13.6%, Na2O 8.1%, CdO8.9%, SO37.8%, ZnO 5.9%, K2O 1.6%, SiO21.5%, MgO 1.0%, Al2O30.5% and some trace substances; the main chemical composition of plant ash is SiO258.2%, Al2O316.8%, CaO 10.0%, Fe2O37.0%, SO32.0%, MgO1.9%;

[0068] (2) The ratio of fly ash to plant ash is 33:67, with a total of 5g sample. Weigh 1.65g of fly ash sample, crush, dry, grind, and screen to a particle size of less than 150μm, weigh 3.35g of plant ash, crush, dry, grind, and screen to a particle size of less than 150μm, and then mix. The chemical composition of the mixed sample is SiO2 39.49%, CaO 21.61%, Al2O3 11.41%, Cl 4.56%, Na2O4.36%, SO3 3.88%, CdO 2.94%, ZnO 1.94%, MgO1.60%, K2O 1.30%, and some trace substances.

[0069] 5g of the mixed material was placed in a corundum crucible and treated in a tubular resistance melting furnace at 1400℃ for 2.0h. The resulting slag was naturally cooled in the air and analyzed after crushing and grinding. The heating rate of the tubular furnace was 10℃ / min below 1000℃ and 5℃ / min between 1000℃ and 1400℃. The atmosphere was air.

[0070] The obtained rough product is cut, ground and polished to obtain the obtained product.

[0071] Test results: The product prepared according to the above parameters has an amorphization degree of 25.6%. The XRD spectrum shows that there are still many crystal diffraction peaks, and amorphization has not been achieved. The density is 1.3g / cm 3The heavy metal leaching levels are as follows: Cr leaching level is 0.46±0.02mg / L, Cu leaching level is 5.88±0.01mg / L, Zn leaching level is 107.4±1.20mg / L, Cd leaching level is 0.44±0.01mg / L, and Pb leaching level is 0.64±0.01mg / L. It does not meet the requirements of amorphous glass composite products.

Claims

1. A method for preparing fly ash vitrified composite materials based on hot-pressing coupling with CaO-Al2O3-SiO2 three-phase ratio adjustment, characterized in that: The steps include: Step 1: Composition analysis of raw materials: Analyze the composition of fly ash, waste glass powder, silica sand and plant ash respectively; Step 2: Based on the FToxid database of Factsage, the liquidus surface projection diagram of the CaO, Al2O3, SiO2 ternary system is calculated in the Equilib module to obtain the melting temperatures of mixed substances of CaO, Al2O3, SiO2 with different proportions; according to the melting temperatures of different proportions, the three-phase material ratio range with a melting temperature below 1200°C is further divided into CaO:Al2O3:SiO2=20~30:1~12:30~45; the ratio within the three-phase material ratio range is selected to deduce the mixing ratio of fly ash and other raw materials; Step 3: Preparation of raw materials: crushing and screening fly ash, waste glass powder, silica sand and plant ash respectively; Step 4: mixing fly ash with any one or more of waste glass powder, silica sand and plant ash; Step 5, pressing the mixture of step 4 into a shape; Step 6, melting the pressed mixture at high temperature, annealing, and program cooling to obtain the amorphous glass crude product; Step 7: Cut, beat and polish the rough amorphous glass product to obtain an amorphous glass composite material product.

2. The method for preparing fly ash vitrified composite material by hot-pressing coupling based on adjusting the three-phase ratio of CaO-Al2O3-SiO2 according to claim 1 is characterized in that: The particle size of the fly ash is not more than 150 μm, and the three-phase ratio of CaO-Al2O3-SiO2 of the fly ash is CaO:Al2O3:SiO2=30~50:0~15:0~10; the particle size of the waste glass powder is not more than 150 μm, and the three-phase ratio of CaO-Al2O3-SiO2 of the waste glass powder is CaO:Al2O3:SiO2=0~10:0~20:50~80; the particle size of the silica sand is not more than 150 μm, and the three-phase ratio of CaO-Al2O3-SiO2 of the silica sand is CaO:Al2O3:SiO2=0~5:0~5:85~98; the particle size of the plant ash is not more than 150 μm, and the three-phase ratio of CaO-Al2O3-SiO2 of the plant ash is CaO:Al2O3:SiO2=0~10:10~30:40~70.

3. The method for preparing fly ash vitrified composite material by hot-pressing coupling based on adjusting the three-phase ratio of CaO-Al2O3-SiO2 according to claim 1 is characterized in that: When fly ash is mixed with waste glass powder, the mixed mass ratio is 57:43 to 40:60; when fly ash is mixed with silica sand, the mixed mass ratio is 65:35 to 60:40; when fly ash is mixed with wood ash, the mixed mass ratio is 50:50 to 25:

75.

4. The method of preparing fly ash vitrified composite material by hot-pressing coupling based on adjusting the three-phase ratio of CaO-Al2O3-SiO2 according to claim 1, characterized in that: The pressing pressure is 10-20 MPa, and the pressing time is 100-200 s.

5. The method for preparing fly ash vitrified composite material by hot-pressing coupling based on adjusting the three-phase ratio of CaO-Al2O3-SiO2 according to claim 1 is characterized in that: The experiment was carried out in a high-temperature tube furnace with a melting temperature of 1100°C to 1400°C, a heating rate of 10°C to 25°C / min below 1000°C, and 5°C to 10°C / min between 1000°C and 1400°C. After reaching the specified temperature, the temperature was kept for 30min to 120min, and the cooling rate was 10°C to 20°C / min. The formed mass was placed in a corundum crucible.

6. Amorphous glass obtained by a method for preparing fly ash vitrified composite materials by hot-pressing coupling based on adjusting the ratio of the three phases of CaO-Al2O3-SiO2 as described in any one of claims 1-5.

7. A device for preparing fly ash vitrified composite materials by hot-pressing coupling based on adjusting the three-phase ratio of CaO-Al2O3-SiO2, characterized in that: It includes a crushing and screening device, a premixing and drying device, a molding and processing device, a molten vitrification device, and a grinding and molding device; the crushing and screening device, the premixing and drying device, the molding and processing device, and the molten vitrification device are connected in sequence, and the secondary fly ash outlet of the molten vitrification device is connected to a recovery device for replenishing raw fly ash; the molten product outlet of the molten vitrification device is connected to the grinding and molding device.

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