System and method for extracting aluminum from high-alumina fly ash by alkali method and producing carbon dioxide adsorbent from waste residue

Abstract

The system and method for extracting aluminum from high-aluminum fly ash by alkali method and preparing carbon dioxide adsorbent from waste residue belong to the field of comprehensive treatment of fly ash. The system comprises an alkali method pre-desilication reactor, a hydrothermal alkali method aluminum extraction reactor, a carbonization aluminum extraction reactor, an aluminum product calcining furnace, a silicon-rich alkali liquor regeneration reactor, an aluminum extraction waste liquid regeneration reactor, a solid waste-based carbon dioxide adsorbent calcining furnace and a solid-liquid separation device. Through the double steps of alkali leaching and carbonization aluminum extraction, the present application can efficiently extract aluminum elements from fly ash, greatly improving the resource utilization rate. While extracting aluminum elements and producing aluminum hydroxide products, the present application also fully utilizes the calcium and silicon-rich waste residue produced during the reaction process. Through calcination treatment, these waste residues are converted into calcium oxide, tricalcium silicate and dicalcium silicate with excellent carbon dioxide adsorption capacity, and then efficient carbon dioxide adsorbent is prepared, realizing real waste resource utilization.

Description

Technical Field

[0001] This invention relates to the field of comprehensive fly ash treatment. In view of the current situation of unreasonable utilization of waste liquid and waste residue in the process of aluminum extraction from fly ash, an innovative solution is proposed, specifically involving a system and method for alkaline aluminum extraction from high-alumina fly ash and the production of carbon dioxide adsorbent from waste residue. Background Technology

[0002] Fly ash is the fine ash collected from the flue gas after coal combustion. It is a major solid waste discharged from coal-fired power plants and urban district heating boilers, and is currently the largest single solid waste in my country, with a cumulative stockpile exceeding 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%), with a total alumina content of 813 million tons, similar to the total amount of bauxite discovered in my country. The resource utilization of fly ash is of great significance for achieving sustainable environmental and economic development.

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

[0004] Current research on fly ash aluminum extraction often fails to adequately address the waste liquid and residue. The waste liquid may contain various hazardous substances, and direct discharge could cause secondary pollution. Furthermore, the stockpiling of waste residue can occupy land resources and pose risks of dust and leachate pollution. Few studies truly focus on the treatment of waste liquid and residue, resulting in a still relatively high environmental risk during fly ash aluminum extraction.

[0005] This invention combines alkaline aluminum extraction from fly ash, preparation of carbon dioxide adsorbent from aluminum extraction slag, and reuse of aluminum extraction waste liquid. First, hydrothermal pre-desiliconization separates some silicon and aluminum from the fly ash, improving subsequent aluminum extraction efficiency. The pre-desiliconized fly ash is then used for aluminum extraction via an alkaline process, and the alkaline solution is further purified by carbonization. Finally, all waste residue from the reaction process is used as a CO2 adsorbent, and all alkaline solution is treated and reused. Therefore, this process maximizes the conversion of fly ash into valuable components, significantly improving the efficiency of the aluminum extraction system. Summary of the Invention

[0006] This invention provides a system and method for aluminum extraction from high-alumina fly ash using an alkaline process and for producing carbon dioxide adsorbents from the waste residue. It not only enables the utilization of aluminum in fly ash but also prepares carbon dioxide adsorbents from the waste residue generated during the reaction process, and treats and reuses all waste liquid, thus achieving systematic utilization of fly ash.

[0007] The technical solution of this invention:

[0008] A system for aluminum extraction from high-alumina fly ash using an alkaline method and for producing carbon dioxide adsorbent from waste residue, the system comprising an alkaline pre-desiliconization reactor, a hydrothermal alkaline aluminum extraction reactor, a carbonization aluminum extraction reactor, an aluminum product calcination furnace, a silicon-rich alkaline solution regeneration reactor, an aluminum extraction waste liquid regeneration reactor, a solid waste-based carbon dioxide adsorbent calcination furnace, and a solid-liquid separation device.

[0009] The outlets of the alkaline pre-desiliconization reactor, the hydrothermal alkaline aluminization reactor, the carbide aluminization reactor, the silica-rich alkaline solution regeneration reactor, and the aluminization waste liquid regeneration reactor are connected to the inlets of solid-liquid separation devices A, B, C, D, and E, respectively. The liquid phase outlet of solid-liquid separation device A is connected to the inlet of the silica-rich alkaline solution regeneration reactor, and the solid phase outlet of solid-liquid separation device A is connected to the inlet of the hydrothermal alkaline aluminization reactor. The liquid phase outlet of solid-liquid separation device B is connected to the inlet of the carbide aluminization reactor, and the solid phase outlet of solid-liquid separation device B is connected to the inlet of the hydrothermal alkaline aluminization reactor. The solid phase outlet of solid-liquid separation device C is connected to the inlet of the aluminum extraction waste liquid regeneration reactor, and the solid phase outlet of solid-liquid separation device C is connected to the inlet of the aluminum product calcination furnace; the liquid phase outlet of solid-liquid separation device D is connected to the inlet of the alkaline pre-desiliconization reactor, and the solid phase outlet of solid-liquid separation device D is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcination furnace; the liquid phase outlet of solid-liquid separation device E is connected to the inlet of the hydrothermal alkaline aluminum extraction reactor, and the solid phase outlet of solid-liquid separation device E is connected to the inlet of the solid waste-based carbon dioxide adsorbent calcination furnace.

[0010] The method for aluminum extraction from high-alumina fly ash using the alkaline process and the production of carbon dioxide adsorbent from waste residue is as follows:

[0011] High-alumina fly ash and desilication alkaline solution are added to an alkaline pre-desilication reactor. After mixing in the alkaline pre-desilication reactor, an alkaline pre-desilication reaction is carried out. The mixture is then fed into solid-liquid separation unit A. The resulting solid product, desilication fly ash, enters a hydrothermal alkaline aluminization reactor, while the liquid product, silica-rich alkaline solution, is fed into a silica-rich alkaline solution regeneration reactor. Calcium oxide and aluminization alkaline solution are added to the hydrothermal alkaline aluminization reactor along with the desilication fly ash. After mixing in the hydrothermal alkaline aluminization reactor, a hydrothermal alkaline aluminization reaction is carried out. The mixture is then fed into solid-liquid separation unit B. The liquid product, aluminum-containing alkaline solution, is fed into a carbonization aluminization reactor, while the solid product, desilication fly ash, enters a solid waste-based carbon dioxide adsorbent calciner. Carbon dioxide is introduced into the carbonization aluminization reactor, where the aluminum-containing alkaline solution and carbon dioxide undergo a carbonization aluminization reaction. The mixture then enters solid-liquid separation unit C. The liquid product is fed into an aluminization waste liquid regeneration reactor, while the resulting solid product, aluminum hydroxide precipitate, is fed into an aluminum product calciner and calcined to produce alumina.

[0012] Calcium oxide is added to the silica-rich alkaline solution regeneration reactor along with the silica-rich alkaline solution. The silica-rich alkaline solution regeneration reaction takes place in the reactor, followed by a solid-liquid separation unit D. The liquid phase of the recycled alkaline solution is sent to the alkaline pre-desiliconization reactor for reuse, while the solid calcium-silicon waste residue enters the solid waste-based carbon dioxide adsorbent calcination furnace. Lime slurry is added to the aluminum extraction wastewater regeneration reactor along with the aluminum extraction wastewater. The aluminum extraction wastewater regeneration reaction takes place in the reactor, followed by a solid-liquid separation unit E. The liquid phase of the recycled alkaline solution is sent to the hydrothermal alkaline aluminum extraction reactor for reuse, while the solid calcium carbonate precipitate enters the solid waste-based carbon dioxide adsorbent calcination furnace and is calcined together with the dealuminized fly ash and calcium-silicon waste residue 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, with an alkali concentration of 160-240 g / L, a liquid-to-solid ratio of 3-7:1, a reaction temperature of 90-150℃, and a pre-desiliconization time of 2-4 h.

[0014] In the hydrothermal alkaline 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 concentration of the alkali solution is 340-440 g / L, the liquid-to-solid ratio is 8-13, the calcium-to-silicon ratio is 0.7-1.7, the reaction temperature is 250-310℃, and the reaction time is 2-4 h.

[0015] In the aforementioned carbide aluminization reaction, the CO2 introduction rate is 0.5-2 m. 3 / h;

[0016] In the regeneration reaction of the silicon-rich alkaline solution, the calcium-to-silicon ratio is 0.7-1.7, the reaction temperature is 60-110℃, and the reaction time is 0.5-2h.

[0017] In the aluminum product calcination furnace, the calcination temperature is 800-1400℃ and the calcination time is 1-4h.

[0018] In the aluminum extraction waste liquid regeneration reaction, the calcium-to-carbon ratio of the added lime slurry is 0.8-1.8, the reaction temperature is 20-60℃, and the reaction time is 1-4h.

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

[0020] The beneficial effects of this invention are:

[0021] (1) Given that fly ash contains abundant aluminum resources, the present invention can efficiently extract aluminum from fly ash through a dual process of alkaline leaching and carbonization, which greatly improves the resource utilization rate.

[0022] (2) While extracting aluminum and producing aluminum hydroxide, this invention also makes full use of the calcium- and silicon-rich waste residue generated during the reaction. Through calcination, this waste residue is converted into calcium oxide, tricalcium silicate, and dicalcium silicate, which have excellent carbon dioxide adsorption capacity, thereby preparing a highly efficient carbon dioxide adsorbent and realizing true waste resource utilization.

[0023] (3) In the entire reaction process of the present invention, all waste liquid and waste residue are fully utilized, ensuring that there is no waste or 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. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the method.

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

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

[0027] Figure 4 This is the XRD pattern of adsorbent A obtained in Comparative Example 1 of this method.

[0028] Figure 5 This is a graph showing the adsorption performance of adsorbent A obtained in Comparative Example 1 of this method.

[0029] Figure 6 This is the XRD pattern of adsorbent B obtained in Comparative Example 2 of this method.

[0030] Figure 7 This is a graph showing the adsorption performance of adsorbent B obtained in Comparative Example 2 of this method.

[0031] Figure 8 This is the XRD pattern of adsorbent propylene obtained in Comparative Example 3 of this method.

[0032] Figure 9 This is a graph showing the adsorption performance of adsorbent C obtained in Comparative Example 3 using this method. Detailed Implementation

[0033] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Example:

[0035] High-alumina fly ash and 5 mol / L sodium hydroxide desilication alkali solution are added to the alkaline pre-desilication reactor at a solid-liquid ratio of 1:5. After mixing in the alkaline pre-desilication reactor, the mixture undergoes an alkaline pre-desilication reaction at 130°C for 210 minutes. The mixture is then fed into solid-liquid separation device A. The resulting solid product, desilicationized fly ash, enters the hydrothermal alkaline aluminization reactor, while the liquid product, silica-rich alkali solution, is fed into the silica-rich alkali solution regeneration reactor. Along with the desilicationized fly ash, calcium oxide is added to the hydrothermal alkaline aluminization reactor at a calcium-silicon ratio of 1.1:1, and 10 mol / L sodium hydroxide aluminization alkali solution is added at a solid-liquid ratio of 1:10. After mixing in the hydrothermal alkaline aluminization reactor, the mixture undergoes a hydrothermal alkaline aluminization reaction at 275°C for 240 minutes. The mixture is then fed into solid-liquid separation device B. The liquid product, aluminum-containing alkali solution, is fed into the carbonization aluminization reactor, while the solid product, dealuminized fly ash, enters the solid waste-based carbon dioxide adsorbent calciner. Carbon dioxide was introduced into the alumina extraction reactor at 25°C at a rate of 1 m³ / min. 3 / h, aluminum-containing alkaline solution and carbon dioxide are reacted in a carbonization aluminum extraction reactor to carry out a carbonization aluminum extraction reaction, 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 resulting solid phase product aluminum hydroxide precipitate is sent to the aluminum product calcination furnace. The calcination temperature is 900℃ and the calcination time is 210 minutes, and the calcination is to produce alumina product.

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

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

[0038] Five repeated carbon dioxide adsorption performance tests were conducted at 750℃ and a carbon dioxide flow rate of 20 ml / min. After each adsorption cycle, the adsorbent was calcined at 850℃ for 10 minutes to restore its original state. The test results are as follows: Figure 3 The results showed 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 dealuminized fly ash obtained in the example were taken out and calcined at 1100°C for 180 minutes, wherein the mass ratio of calcium carbonate precipitate to dealuminized fly ash was 1:2, to obtain adsorbent A. Its XRD pattern is shown below. Figure 4 The results showed that, compared to the solid waste-based carbon dioxide adsorbent obtained in the examples, it lacked the calcium silicate crystalline phase, resulting in adsorbent A lacking a framework structure and having a weaker adsorption capacity. Its carbon dioxide adsorption performance test results are as follows: Figure 5 As shown in the figure, its adsorption capacity is low.

[0041] Comparative Example 2:

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

[0043] Comparative Example 3:

[0044] The calcium silicate 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 calcium silicate waste residue to calcium carbonate precipitate was 1:1, and the product obtained was adsorbent C. Its XRD pattern is shown below. Figure 8 The results showed that the solid waste-based carbon dioxide adsorbent obtained in the examples lacked calcium aluminate, resulting in lower anti-sintering ability of the adsorbent. Its carbon dioxide adsorption performance test results are as follows: Figure 9 As shown in the figure, its anti-sintering performance during carbon dioxide adsorption is poor.

Claims

1. A system for extracting aluminum from high-alumina fly ash by an alkali process and producing a carbon dioxide adsorbent from waste residue, characterized by comprising: The system comprises an alkali pre-desilication reactor, a hydrothermal alkali aluminum extraction reactor, a carbonization aluminum extraction reactor, an aluminum product calcining furnace, a silicon-rich alkali solution 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-desilication 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 solution 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 alkali pre-desilication 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.

2. A method for extracting aluminum from high-alumina fly ash by alkali process and producing a carbon dioxide adsorbent from waste residue, characterized in that, The system for high-aluminum fly ash alkali aluminum extraction and waste residue preparation of carbon dioxide adsorbent according to claim 1 has the following process: The high-aluminum fly ash and desilication alkali solution are added into the alkali pre-desilication reactor, mixed and subjected to alkali pre-desilication reaction, and then sent into the solid-liquid separation device A; the obtained solid phase product desilication fly ash is sent into the hydrothermal alkali aluminum extraction reactor, and the liquid phase product silicon-rich alkali solution is sent into the silicon-rich alkali solution regeneration reactor; calcium oxide and aluminum extraction alkali solution are added into the hydrothermal alkali aluminum extraction reactor together with the desilication fly ash, mixed and subjected to hydrothermal alkali aluminum extraction reaction, and then sent into the solid-liquid separation device B; the liquid phase product aluminum-containing alkali solution is sent into the carbonization aluminum extraction reactor, and the solid phase product de-aluminum fly ash is sent into the solid waste-based carbon dioxide adsorbent calcining furnace; Carbon dioxide is introduced into the carbonization aluminum extraction reactor, and the aluminum-containing alkali solution and the carbon dioxide are subjected to carbonization aluminum extraction reaction in the carbonization aluminum extraction reactor, and then sent into the solid-liquid separation device C; the liquid phase product is sent into the aluminum extraction waste liquid regeneration reactor, and the obtained solid phase product aluminum hydroxide precipitate is sent into the aluminum product calcining furnace and calcined into aluminum oxide product; Calcium oxide is added into the silicon-rich alkali solution regeneration reactor together with the silicon-rich alkali solution, subjected to silicon-rich alkali solution regeneration reaction, and then sent into the solid-liquid separation device D; the liquid phase recycled alkali solution is sent into the alkali pre-desilication reactor for recycling, and the solid phase calcium-silicon waste residue is sent into the solid waste-based carbon dioxide adsorbent calcining furnace; The lime milk is added into the aluminum stripping waste liquid regeneration reactor along with the aluminum stripping waste liquid, and the aluminum stripping waste liquid regeneration reaction is carried out in the aluminum stripping waste liquid regeneration reactor, and then the solid-liquid separation device E is sent, the recycled alkali liquid at the liquid phase outlet is sent into the hydrothermal alkali method aluminum stripping reactor for recycling, and the solid phase calcium carbonate precipitate enters the solid waste based carbon dioxide adsorbent calcining furnace, and is calcined with the dealuminized fly ash and calcium-silicon waste residue to obtain the solid waste based carbon dioxide adsorbent.

3. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide adsorbent from waste residue according to claim 2, characterized in that, The alkali used in the alkali method pre-desiliconization reaction is one or more than two kinds of NaOH, KOH, Ca(OH)2, Na2CO3 or NH4Cl, the alkali concentration is 160-240 g / L, the liquid-solid ratio is 3-7:1, the reaction temperature is 90-150 DEG C, and the pre-desiliconization time is 2-4 h.

4. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide adsorbent from waste residue according to claim 2, characterized in that, The alkali used in the hydrothermal alkali method aluminum stripping reaction is one or more than two kinds of NaOH, KOH, Ca(OH)2, Na2CO3 or NH4Cl, the alkali concentration is 340-440 g / L, the liquid-solid ratio is 8-13, the calcium-silicon ratio is 0.7-1.7, the reaction temperature is 250-310 DEG C, and the reaction time is 2-4 h.

5. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide adsorbent from waste residue according to claim 2, characterized in that, The CO2 feeding rate in the carbonization process for extracting aluminum is 0.5-2 m 3 / h.

6. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide absorbent from waste residue according to claim 2, characterized in that, The calcium-silicon ratio in the rich silicon alkali liquid regeneration reaction is 0.7-1.7, the reaction temperature is 60-110 DEG C, and the reaction time is 0.5-2 h.

7. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide absorbent from waste residue according to claim 2, characterized in that, The calcining temperature in the aluminum product calcining furnace is 800-1400 DEG C, and the calcining time is 1-4 h.

8. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide absorbent from waste residue according to claim 2, characterized in that, The calcium-carbon ratio of the added lime milk in the aluminum stripping waste liquid regeneration reaction is 0.8-1.8, the reaction temperature is 20-60 DEG C, and the reaction time is 1-4 h.

9. The method for extracting aluminum by alkali method from high-aluminum fly ash and producing carbon dioxide absorbent from waste residue according to claim 2, characterized in that, The calcining temperature in the solid waste based carbon dioxide adsorbent calcining process is 800-1200 DEG C, the calcining time is 1-4 h, and the mass ratio of the calcium carbonate precipitate, the dealuminized fly ash and the calcium-silicon waste residue is 1:(1.5-2.5):(0.8-1.4).

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