System and method for extracting aluminum from high-alumina fly ash through alkaline process and preparing carbon dioxide adsorbent from waste residues

Abstract

The invention discloses a system and a method for extracting aluminum from high-alumina fly ash by an alkaline process and preparing a carbon dioxide adsorbent from waste residues, belonging to the field of comprehensive treatment of fly ash. The system comprises an alkaline pre-desiliconization reactor, a hydrothermal alkaline aluminum extraction reactor, a carbonization aluminum extraction reactor, an aluminum product calcining furnace, a silicon-rich alkaline liquid regeneration reactor, an aluminum extraction waste liquid regeneration reactor, a solid waste-based carbon dioxide adsorbent calcining furnace and a solid-liquid separation device. According to the method, the aluminum element can be efficiently extracted from the fly ash through the double steps of aluminum extraction through alkali leaching and aluminum extraction through carbonization, and the resource utilization rate is greatly increased. While the aluminum element is extracted and an aluminum hydroxide product is produced, waste residues rich in calcium and silicon generated in the reaction process are fully utilized. Through calcination treatment, the waste residues are converted into calcium oxide, tricalcium silicate and dicalcium silicate with excellent carbon dioxide adsorption capacity, and then the efficient carbon dioxide adsorbent is prepared, so that real waste resource utilization is realized.

Description

Technical Field

[0001] The invention relates to the field of comprehensive fly ash treatment. Aiming at the current situation of unreasonable utilization of waste liquid and waste residue in the process of extracting aluminum from fly ash, an innovative solution is proposed, specifically relating to a system and method for extracting aluminum from high-aluminum fly ash using an alkaline method and preparing a carbon dioxide adsorbent from waste residue. Background Art

[0002] Fly ash is the fine ash collected from the flue gas after coal combustion. It is the main solid waste discharged from coal-fired power plants and urban centralized heating boilers. It is currently the largest single solid waste in my country, with a cumulative stockpile of over 3 billion tons and an annual output of up to 900 million tons. The main components of fly ash include oxides such as SiO2 (20%-60%) and Al2O3 (10%-50%), of which the total amount of alumina is 813 million tons, which is similar to the total amount of bauxite that has been proven in my country. The resource utilization of fly ash is of great significance to achieving sustainable development of the environment and economy.

[0003] In terms of the comprehensive utilization of fly ash, currently more than 80% of fly ash is used to make building materials such as roadbed materials, concrete admixtures, soil conditioners, etc., but these utilization methods often have low added value and fail to fully tap the potential value of fly ash, resulting in a large amount of aluminum resources being wasted.

[0004] In the current research on fly ash aluminum extraction, waste liquid and waste residue are often not properly treated. The waste liquid may contain a variety of harmful substances. If discharged directly, it will cause secondary pollution to the environment. The stacking of waste residue may also occupy land resources and there is a risk of dust and leachate pollution. Few studies have really focused on the treatment of waste liquid and waste residue, resulting in a high environmental risk in the fly ash aluminum extraction process.

[0005] The present invention combines fly ash alkali method aluminum extraction, aluminum extraction slag preparation of carbon dioxide adsorbent, and aluminum extraction waste liquid recycling. First, a part of the silicon and aluminum in the fly ash is separated by hydrothermal pre-desiliconization to improve the subsequent aluminum extraction efficiency. The fly ash after pre-desiliconization is subjected to an alkali method to extract aluminum, and the aluminum extraction alkali liquid extracts aluminum by carbonization. Finally, all the waste residues in the reaction process are used as CO2 adsorbents, and all the alkali liquids are treated and reused. Therefore, this process can convert fly ash into valuable components to the maximum extent, thereby improving the efficiency of the aluminum extraction system. Summary of the invention

[0006] The present invention is to provide a system and method for extracting aluminum from high-aluminum fly ash by alkaline method and preparing carbon dioxide adsorbent from waste slag. It can not only realize the utilization of aluminum in fly ash, but also prepare the waste slag in the reaction process into carbon dioxide adsorbent, and all waste liquid is processed and reused, thus realizing the systematic utilization of fly ash.

[0007] The technical solution of the present invention:

[0008] A system for extracting aluminum from high-aluminum fly ash using an alkali method and preparing a carbon dioxide adsorbent from waste slag, the system comprising an alkali pre-desiliconization reactor, a hydrothermal alkali aluminum extraction reactor, a carbonization aluminum extraction reactor, an aluminum product calcining furnace, a silicon-rich alkali liquid regeneration reactor, an aluminum extraction waste liquid regeneration reactor, a solid waste-based carbon dioxide adsorbent calcining furnace and a solid-liquid separation device.

[0009] The outlets of the alkali pre-desiliconization reactor, the hydrothermal alkali aluminum extraction reactor, the carbonization aluminum extraction reactor, the silicon-rich alkali liquid regeneration reactor, and the aluminum extraction waste liquid regeneration reactor are respectively connected to the inlets of the solid-liquid separation device A, the solid-liquid separation device B, the solid-liquid separation device C, the solid-liquid separation device D, and the solid-liquid separation device E; the liquid phase outlet of the solid-liquid separation device A is connected to the inlet of the silicon-rich alkali liquid regeneration reactor, and the solid phase outlet of the solid-liquid separation device A is connected to the inlet of the hydrothermal alkali aluminum extraction reactor; the liquid phase outlet of the solid-liquid separation device B is connected to the inlet of the carbonization aluminum extraction reactor, and the solid phase outlet of the solid-liquid separation device B is connected to the inlet of the solid-liquid separation device B. It is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcining furnace; the liquid phase outlet of the solid-liquid separation device C is connected to the inlet of the aluminum extraction waste liquid regeneration reactor, and the solid phase outlet of the solid-liquid separation device C is connected to the inlet of the aluminum product calcining furnace; the liquid phase outlet of the solid-liquid separation device D is connected to the inlet of the alkali pre-desiliconization reactor, and the solid phase outlet of the solid-liquid separation device D is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcining furnace; the liquid phase outlet of the solid-liquid separation device E is connected to the inlet of the hydrothermal alkali aluminum extraction reactor, and the solid phase outlet of the solid-liquid separation device E is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcining furnace.

[0010] The method of extracting aluminum from high-aluminum fly ash by alkaline method and preparing carbon dioxide adsorbent from waste slag, the process is as follows:

[0011] High-aluminum fly ash and desiliconized alkali solution are added to the alkaline pre-desiliconization reactor, mixed in the alkaline pre-desiliconization reactor, and then sent to the solid-liquid separation device A. The obtained solid phase product desiliconized fly ash enters the hydrothermal alkaline aluminum extraction reactor, and the liquid phase product silicon-rich alkali solution is passed into the silicon-rich alkali solution regeneration reactor. Calcium oxide and aluminum extraction alkali solution are added to the hydrothermal alkaline aluminum extraction reactor together with the desiliconized fly ash, mixed in the hydrothermal alkaline aluminum extraction reactor, and then sent to the solid-liquid separation device B. The liquid phase product aluminum-containing alkali solution is sent to the carbonization aluminum extraction reactor, and the solid phase product dealuminized fly ash enters the solid waste-based carbon dioxide adsorbent calcining furnace. Carbon dioxide is passed into the carbonization aluminum extraction reactor, and the aluminum-containing alkali solution and carbon dioxide undergo carbonization aluminum extraction reaction in the carbonization aluminum extraction reactor, and then enter the solid-liquid separation device C. The liquid phase product is sent to the aluminum extraction waste liquid regeneration reactor, and the obtained solid phase product aluminum hydroxide precipitate enters the aluminum product calcining furnace and calcined into an aluminum oxide product.

[0012] Calcium oxide is added to the silicon-rich alkali liquid regeneration reactor along with the silicon-rich alkali liquid, and the silicon-rich alkali liquid regeneration reaction is carried out in the silicon-rich alkali liquid regeneration reactor, and then it is sent to the solid-liquid separation device D. The liquid phase of the recycled alkali liquid is sent to the alkali pre-desiliconization reactor for recycling, and the solid phase calcium silicon waste slag enters the solid waste-based carbon dioxide adsorbent calcining furnace. Lime milk is added to the aluminum extraction waste liquid regeneration reactor along with the aluminum extraction waste liquid, and the aluminum extraction waste liquid regeneration reaction is carried out in the aluminum extraction waste liquid regeneration reactor, and then it is sent to the solid-liquid separation device E. The recycled alkali liquid at the liquid phase outlet is sent to the hydrothermal alkali aluminum extraction reactor for recycling, and the solid phase calcium carbonate precipitate enters the solid waste-based carbon dioxide adsorbent calcining furnace, and is calcined together with the dealuminated fly ash and calcium silicon waste slag to obtain the solid waste-based carbon dioxide adsorbent.

[0013] The alkali for the alkaline pre-desiliconization reaction is one or a mixture of two or more of NaOH, KOH, Ca(OH)2, Na2CO3 or NH4Cl, the alkali solution concentration is 160-240g / L, the liquid-solid ratio is 3-7:1, the reaction temperature is 90-150°C, and the pre-desiliconization time is 2-4h;

[0014] In the hydrothermal alkali aluminum extraction reaction, the alkali used in the reaction is one or a mixture of two or more of NaOH, KOH, Ca(OH)2, Na2CO3 or NH4Cl, the alkali solution concentration is 340-440g / L, the liquid-solid ratio is 8-13, the calcium-silicon ratio is 0.7-1.7, the reaction temperature is 250-310°C, and the reaction time is 2-4h;

[0015] During the carbonization aluminum extraction reaction, the CO2 introduction rate is 0.5-2m 3 / h;

[0016] In the silicon-rich alkali solution regeneration reaction, the calcium-silicon ratio is 0.7-1.7, the reaction temperature is 60-110°C, and the reaction time is 0.5-2h;

[0017] In the aluminum product calcining furnace, the calcining temperature is 800-1400° C. and the calcining time is 1-4 hours;

[0018] In the aluminum extraction waste liquid regeneration reaction, the calcium-carbon ratio of the added lime milk is 0.8-1.8, the reaction temperature is 20-60°C, and the reaction time is 1-4h;

[0019] During the calcination of the solid waste-based carbon dioxide adsorbent, the calcination temperature is 800-1200° C., the calcination time is 1-4 hours, and the mass ratio of calcium carbonate precipitate, dealuminated fly ash, and calcium-silicon waste slag is 1:(1.5-2.5):(0.8-1.4).

[0020] Beneficial effects of the present invention:

[0021] (1) In view of the fact that fly ash contains abundant aluminum resources, the present invention can efficiently extract aluminum from fly ash through the dual steps of alkali leaching and carbonization extraction, thereby greatly improving resource utilization.

[0022] (2) While extracting aluminum and producing aluminum hydroxide products, the present invention also makes full use of the calcium-silicon-rich waste residues generated during the reaction process. Through calcination, these waste residues are converted into calcium oxide, tricalcium silicate and dicalcium silicate with excellent carbon dioxide adsorption capacity, and then a highly efficient carbon dioxide adsorbent is prepared, realizing the true resource utilization of waste.

[0023] (3) In the entire reaction process of the present invention, all waste liquids and waste residues are fully utilized, ensuring that there is no waste and waste liquid discharge in the entire system, thereby significantly improving the overall efficiency of the system and achieving a dual improvement in environmental friendliness and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the method.

[0025] Figure 2 This is the XRD diagram of the solid waste-based carbon dioxide adsorbent obtained in this method embodiment.

[0026] Figure 3 This is a test chart of the adsorption performance of the solid waste-based carbon dioxide adsorbent obtained in this method embodiment.

[0027] Figure 4 This is the XRD diagram of adsorbent A obtained in comparative example 1 of the present method.

[0028] Figure 5 This is a test chart of the adsorption performance of adsorbent A obtained in comparative example 1 of the present method.

[0029] Figure 6 This is the XRD diagram of adsorbent B obtained in comparative example 2 of this method.

[0030] Figure 7 This is a test chart of the adsorption performance of adsorbent B obtained in comparative example 2 of the present method.

[0031] Figure 8 This is the XRD diagram of adsorbent C obtained in comparative example 3 of this method.

[0032] Fig. 9 This is a test chart of the adsorption performance of adsorbent C obtained in comparative example 3 of the present method. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below based on the accompanying drawings and embodiments.

[0034] Example:

[0035] High-aluminum fly ash and sodium hydroxide desiliconization alkali solution with a concentration of 5 mol / L are added to the alkaline pre-desiliconization reactor at a solid-liquid ratio of 1:5. After mixing in the alkaline pre-desiliconization reactor, the alkaline pre-desiliconization reaction is carried out at 130°C for 210 minutes, and then sent to the solid-liquid separation device A. The obtained solid phase product desiliconized fly ash enters the hydrothermal alkaline aluminum extraction reactor, and the liquid phase product silicon-rich alkali solution is passed into the silicon-rich alkali solution regeneration reactor. Calcium oxide is added to the hydrothermal alkaline aluminum extraction reactor at a calcium-silicon ratio of 1.1:1, and sodium hydroxide aluminum extraction alkali solution with a concentration of 10 mol / L is added at a solid-liquid ratio of 1:10. After mixing in the hydrothermal alkaline aluminum extraction reactor, the hydrothermal alkaline aluminum extraction reaction is carried out at 275°C for 240 minutes, and then sent to the solid-liquid separation device B. The liquid phase product aluminum-containing alkali solution is sent to the carbonization aluminum extraction reactor, and the solid phase product dealuminized fly ash enters the solid waste-based carbon dioxide adsorbent calcining furnace. Carbon dioxide was introduced into the carbonization reactor at 25°C at a rate of 1 m 3 / h, the aluminum-containing alkali liquid and carbon dioxide undergo carbonization and aluminum extraction reaction in the carbonization and aluminum extraction reactor, and then enter the solid-liquid separation device C, the liquid phase product is sent to the aluminum extraction waste liquid regeneration reactor, and the obtained solid phase product aluminum hydroxide precipitate enters the aluminum product calcining furnace, the calcination temperature is 900°C, the calcination time is 210 minutes, and the calcination is performed to obtain an alumina product.

[0036] Calcium oxide is added into the silicon-rich alkali solution regeneration reactor at a calcium-silicon ratio of 1.1:1 along with the silicon-rich alkali solution. The silicon-rich alkali solution regeneration reaction is carried out at 100°C in the silicon-rich alkali solution regeneration reactor for 120 minutes, and then the silicon-rich alkali solution is sent to the solid-liquid separation device D. The liquid phase recycled alkali solution is sent to the alkaline pre-desiliconization reactor for recycling, and the solid phase calcium silicon waste slag enters the solid waste-based carbon dioxide adsorbent calcining furnace. Lime milk is added into the aluminum extraction waste liquid regeneration reactor at a calcium-carbon ratio of 1:1 along with the aluminum extraction waste liquid. The aluminum extraction waste liquid is regenerated at 25°C in the aluminum extraction waste liquid regeneration reactor for 1.5 hours, and then sent to the solid-liquid separation device E. The recycled alkali liquid at the liquid phase outlet is sent to the hydrothermal alkali aluminum extraction reactor for reuse. The solid phase calcium carbonate precipitate enters the solid waste-based carbon dioxide adsorbent calcining furnace and is calcined at 1100°C for 180 minutes together with dealuminized fly ash and calcium-silicon waste slag. The mass ratio of calcium carbonate precipitate, dealuminized fly ash and calcium-silicon waste slag is 1:2:1, and the final product, solid waste-based carbon dioxide adsorbent, is obtained.

[0037] The final product, solid waste-based carbon dioxide adsorbent, is characterized by XRD patterns as shown in Figure 2 The results showed that it contained: ① CaO with carbon dioxide adsorption performance; ② SiO2 and 2CaO·SiO2 dicalcium silicate that constitute the adsorbent skeleton structure; ③ 3CaO·Al2O3 calcium aluminate that provides anti-sintering performance for the adsorbent.

[0038] The carbon dioxide adsorption performance test was repeated 5 times at 750°C and a carbon dioxide flow rate of 20 ml / min. After each adsorption, the adsorbent was calcined at 850°C for 10 minutes to recover. The test results are shown in the figure. Figure 3 The results show that the carbon dioxide adsorbent prepared by this method has good adsorption performance and good anti-sintering ability.

[0039] Comparative Example 1:

[0040] The calcium carbonate precipitate and dealuminated fly ash obtained in the example were taken out and calcined at 1100°C for 180 minutes, wherein the mass ratio of the calcium carbonate precipitate to the dealuminated fly ash was 1:2, and the product obtained was adsorbent A. Its XRD pattern is shown as follows Figure 4 The results show that compared with the solid waste-based carbon dioxide adsorbent obtained in Example 1, the solid waste-based carbon dioxide adsorbent lacks the calcium silicate crystal phase, resulting in the adsorbent A not having a skeleton structure and having a weaker adsorption capacity. The test results of its carbon dioxide adsorption performance are as follows Figure 5 As shown, the figure shows that its adsorption capacity is low.

[0041] Comparative Example 2:

[0042] The dealuminized fly ash and calcium-silicon waste slag obtained in the example were taken out and calcined at 1100°C for 180 minutes, wherein the mass ratio of dealuminized fly ash to calcium-silicon waste slag was 2:1, and the obtained product was adsorbent B. Its XRD pattern is shown as follows Figure 6 The results show that compared with the solid waste-based carbon dioxide adsorbent obtained in the example, the solid waste-based carbon dioxide adsorbent lacks calcium oxide, resulting in weak adsorption performance of the adsorbent. The test results of its carbon dioxide adsorption performance are as follows Figure 7 As shown in the figure, it shows that its carbon dioxide adsorption capacity is weak.

[0043] Comparative Example 3:

[0044] The calcium silicon waste residue and calcium carbonate precipitate obtained in the example were taken out and calcined at 1100°C for 180 minutes, wherein the mass ratio of the calcium silicon waste residue to the calcium carbonate precipitate was 1:1, and the obtained product was adsorbent C. Its XRD pattern is shown as follows: Figure 8 The results show that compared with the solid waste-based carbon dioxide adsorbent obtained in the example, the solid waste-based carbon dioxide adsorbent lacks calcium aluminate, resulting in low anti-sintering ability of the adsorbent. The test results of its carbon dioxide adsorption performance are as follows Fig. 9 As shown in the figure, it shows that its anti-sintering performance is poor during carbon dioxide adsorption.

Claims

1. A system for extracting aluminum from high-aluminum fly ash using alkaline method and preparing carbon dioxide adsorbent from waste slag, characterized in that: The system includes an alkali pre-desiliconization reactor, a hydrothermal alkali aluminum extraction reactor, a carbonization aluminum extraction reactor, an aluminum product calcining furnace, a silicon-rich alkali liquid regeneration reactor, an aluminum extraction waste liquid regeneration reactor, a solid waste-based carbon dioxide adsorbent calcining furnace and a solid-liquid separation device; The outlets of the alkali pre-desiliconization reactor, the hydrothermal alkali aluminum extraction reactor, the carbonization aluminum extraction reactor, the silicon-rich alkali solution regeneration reactor, and the aluminum extraction waste liquid regeneration reactor are respectively connected to the inlets of the solid-liquid separation device A, the solid-liquid separation device B, the solid-liquid separation device C, the solid-liquid separation device D, and the solid-liquid separation device E; The liquid phase outlet of the solid-liquid separation device A is connected to the inlet of the silicon-rich alkali liquid regeneration reactor, and the solid phase outlet of the solid-liquid separation device A is connected to the inlet of the hydrothermal alkali aluminum extraction reactor; The liquid phase outlet of the solid-liquid separation device B is connected to the inlet of the carbonization aluminum extraction reactor, and the solid phase outlet of the solid-liquid separation device B is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcining furnace; the liquid phase outlet of the solid-liquid separation device C is connected to the inlet of the aluminum extraction waste liquid regeneration reactor, and the solid phase outlet of the solid-liquid separation device C is connected to the inlet of the aluminum product calcining furnace; the liquid phase outlet of the solid-liquid separation device D is connected to the inlet of the alkaline pre-desiliconization reactor, and the solid phase outlet of the solid-liquid separation device D is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcining furnace; the liquid phase outlet of the solid-liquid separation device E is connected to the inlet of the hydrothermal alkaline aluminum extraction reactor, and the solid phase outlet of the solid-liquid separation device E is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcining furnace.

2. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: The system for extracting aluminum from high-aluminum fly ash by alkaline method and preparing carbon dioxide adsorbent from waste slag as described in claim 1 is adopted, and the process is as follows: High-aluminum fly ash and desiliconized alkali solution are added to an alkali pre-desiliconization reactor, mixed in the alkali pre-desiliconization reactor, and then sent to a solid-liquid separation device A. The obtained solid phase product, desiliconized fly ash, enters a hydrothermal alkali aluminum extraction reactor, and the liquid phase product, silicon-rich alkali solution, is passed into a silicon-rich alkali solution regeneration reactor; calcium oxide and aluminum-extracting alkali solution are added to the hydrothermal alkali aluminum extraction reactor together with the desiliconized fly ash, mixed in the hydrothermal alkali aluminum extraction reactor, and then sent to a solid-liquid separation device B. The liquid phase product, aluminum-containing alkali solution, is sent to a carbonization aluminum extraction reactor, and the solid phase product, dealuminized fly ash, enters a solid waste-based carbon dioxide adsorbent calcining furnace; Carbon dioxide is introduced into the carbonization aluminum extraction reactor, and the aluminum-containing alkali liquid and carbon dioxide undergo a carbonization aluminum extraction reaction in the carbonization aluminum extraction reactor, and then enter the solid-liquid separation device C, and the liquid phase product is sent to the aluminum extraction waste liquid regeneration reactor, and the obtained solid phase product aluminum hydroxide precipitates and enters the aluminum product calcining furnace to be calcined into an aluminum oxide product; Calcium oxide is added to the silicon-rich alkali solution regeneration reactor together with the silicon-rich alkali solution, and the silicon-rich alkali solution regeneration reaction is carried out in the silicon-rich alkali solution regeneration reactor, and then sent to the solid-liquid separation device D, the liquid phase of the recycled alkali solution is sent to the alkaline pre-desiliconization reactor for recycling, and the solid phase calcium silicon waste slag enters the solid waste-based carbon dioxide adsorbent calcining furnace; Lime milk is added to the aluminum extraction waste liquid regeneration reactor together with the aluminum extraction waste liquid, and the aluminum extraction waste liquid regeneration reaction is carried out in the aluminum extraction waste liquid regeneration reactor, and then it is sent to the solid-liquid separation device E, and the reused alkali liquid at the liquid phase outlet is sent to the hydrothermal alkali aluminum extraction reactor for reuse, and the solid calcium carbonate precipitate enters the solid waste-based carbon dioxide adsorbent calcining furnace, and is calcined together with the dealuminized fly ash and calcium-silicon waste slag to obtain the solid waste-based carbon dioxide adsorbent.

3. The method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag according to claim 2, characterized in that: The alkali for the alkaline pre-desiliconization reaction is one or a mixture of two or more of NaOH, KOH, Ca(OH)2, Na2CO3 or NH4Cl, the alkali solution concentration is 160-240g / L, the liquid-to-solid ratio is 3-7:1, the reaction temperature is 90-150°C, and the pre-desiliconization time is 2-4h.

4. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: In the hydrothermal alkali aluminum extraction reaction, the alkali used in the reaction is one or a mixture of two or more of NaOH, KOH, Ca(OH)2, Na2CO3 or NH4Cl, the alkali solution concentration is 340-440g / L, the liquid-solid ratio is 8-13, the calcium-silicon ratio is 0.7-1.7, the reaction temperature is 250-310°C, and the reaction time is 2-4h.

5. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: During the carbonization aluminum extraction reaction, the CO2 introduction rate is 0.5-2m 3 / h.

6. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: In the silicon-rich alkali solution regeneration reaction, the calcium-silicon ratio is 0.7-1.7, the reaction temperature is 60-110° C., and the reaction time is 0.5-2 h.

7. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: In the aluminum product calcining furnace, the calcining temperature is 800-1400° C. and the calcining time is 1-4 hours.

8. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: In the aluminum extraction waste liquid regeneration reaction, the calcium-carbon ratio of the added lime milk is 0.8-1.8, the reaction temperature is 20-60°C, and the reaction time is 1-4h.

9. A method for extracting aluminum from high-aluminum fly ash using an alkali process and preparing a carbon dioxide adsorbent from waste slag, characterized in that: During the calcination process of the solid waste-based carbon dioxide adsorbent, the calcination temperature is 800-1200° C., the calcination time is 1-4 hours, and the mass ratio of calcium carbonate precipitate, dealuminized fly ash, and calcium-silicon waste slag is 1:(1.5-2.5):(0.8-1.4).

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