Method for preparing high-purity vaterite from desulfurization ash and application thereof

Abstract

The application discloses a method for preparing high-purity ball calcite by taking desulfurization ash as raw material, and application thereof, and belongs to the technical field of industrial solid waste resource utilization and carbon emission reduction. The method takes dry / half-dry desulfurization ash as a special calcium source, converts non-active calcium into high-activity calcium hydroxide through alkaline activation, adopts alpha-amino acid to complex and leach calcium ions at pH=9-12, and then passes in CO2 to mineralize and crystallize at pH=6-7, so that a ball calcite product with high purity is finally prepared, and the mineralized filtrate can be recycled. The application does not need an ammonia source, is energy-saving at room temperature, couples desulfurization ash solid waste consumption with CO2 mineralization emission reduction, has excellent product stability, is suitable for industrial production, and can be widely applied to the fields of solid waste treatment, carbon capture, biological medical materials and high-end fillers.

Description

Technical Field

[0001] This invention belongs to the field of solid waste resource utilization and calcium carbonate synthesis technology, and specifically relates to a method and application for preparing high-purity aragonite using desulfurization ash as raw material. Background Technology

[0002] The iron and steel metallurgy and thermal power generation industries commonly use CFB and LIFAC dry / semi-dry flue gas desulfurization technologies. These processes generate large amounts of desulfurization ash solid waste, which has a high calcium content but low activity. Direct storage of this waste easily causes secondary pollution, and its resource utilization rate is less than 30%. Desulfurization ash, as a natural alkaline calcium source, can be used for CO2 mineralization to produce calcium carbonate. However, existing desulfurization ash mineralization processes can only produce low-value calcite-type calcium carbonate, failing to achieve high-value utilization of solid waste.

[0003] Aragonite is a metastable crystal form of calcium carbonate, possessing advantages such as large specific surface area, high porosity, and good biocompatibility, making it highly valuable for applications in drug sustained release, composite material reinforcement, and high-end fillers. However, aragonite is thermodynamically unstable and readily transforms into calcite in aqueous solutions, making the preparation of high-purity, stable aragonite a significant challenge in the industry.

[0004] In the prior art, patent CN121247863A discloses a method for preparing aragonite, which uses calcium chloride, carbide slag, etc. as calcium sources and employs a composite system composed of an ammonia source and a surfactant to prepare aragonite by controlling the reaction pH to 8-12 throughout the process. While this technology can obtain aragonite of a certain purity, it has three major drawbacks: Poor calcium source compatibility: The pretreatment process was not designed for the low calcium activity characteristics of desulfurization ash, making it impossible to directly use desulfurization ash as a dedicated calcium source, and making it difficult to achieve large-scale resource utilization of desulfurization ash. Inappropriate pH control: A single pH range of 8-12 was used throughout the process, without distinguishing the pH requirements for calcium leaching and mineralization reactions, which limited the nucleation and stabilization effects of aragonite. The system is redundant and costly: it relies on ammonia sources to build a buffer system, fails to achieve filtrate recycling, and does not couple CO2 mineralization and emission reduction, resulting in insufficient environmental and economic benefits.

[0005] In addition, existing aragonite preparation technologies generally suffer from problems such as low activation rate of desulfurized ash calcium, aragonite purity <95%, easy phase transformation, and inability to adapt the process to industrial solid waste, making it impossible to simultaneously achieve the triple goals of desulfurized ash solid waste disposal, CO2 mineralization emission reduction, and high-purity aragonite preparation.

[0006] Therefore, developing a method for preparing aragonite using desulfurization ash as the sole calcium source, alkaline activation of the calcium source, precise segmented pH control, and directional stabilization of α-amino acids has become a pressing technical problem to be solved in this field. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a method for preparing high-purity aragonite from desulfurization ash. By activating the inactive calcium in the desulfurization ash through alkaline activation pretreatment, regulating the amphoteric properties of α-amino acids, and precisely controlling the pH in stages, the method achieves efficient resource utilization of desulfurization ash, CO2 mineralization and emission reduction, and simultaneously prepares aragonite products with a purity >99% and excellent stability. Furthermore, the filtrate can be recycled, significantly reducing production costs.

[0008] To achieve the above objectives, the present invention provides a method for preparing high-purity aragonite using desulfurization ash as raw material, comprising the following steps: S1: The desulfurization ash is mixed with an alkaline activation solution, and after the reaction, solid-liquid separation is performed to obtain a solid product rich in calcium hydroxide. S2: Add a surfactant solution to the solid product obtained in step S1, react for a period of time, and then perform solid-liquid separation to obtain calcium ion leachate. S3: A carbon dioxide-containing gas is introduced into the calcium ion leachate obtained in step S2 to carry out a mineralization reaction. After the reaction is completed, solid-liquid separation, washing, and drying are performed to obtain aragonite-type calcium carbonate. In step S2, the pH of the system after mixing the surfactant solution and the solid product is 9-12. Taking α-amino acid surfactant as an example, it is an amphoteric compound, mainly existing in anionic form (H2N-CH2-COO) in an alkaline environment. - It exists. This anionic form can react with Ca in solution. 2+ Formation of stable soluble complexes, thereby reducing free Ca2+. 2+ This increases the activity of calcium ions and simultaneously enhances the system's total calcium ion carrying capacity, i.e., increases calcium supersaturation. Supersaturation is a key driving force for aragonite nucleation. The solid obtained after desulfurization ash is activated by alkali is mainly Ca(OH)2. Under alkaline conditions of pH 9-12, Ca(OH)2 has moderate solubility and can stably release calcium. 2+ Simultaneously, surfactant anions continuously capture Ca... 2+ The formation of complexes disrupts the dissolution equilibrium and drives the Ca... 2+ Continuous leaching improves calcium extraction efficiency; however, if the pH > 12, the system is too alkaline, which may cause some surfactants (especially amino acids) to undergo irreversible degradation, lose their complexing ability, or interfere with the complexation balance, forming other calcium-hydroxyl precipitates; simultaneously, excessively high OH- ions... - Concentration will compete with amino acids for the binding of Ca. 2+ This reduces complexation efficiency and calcium leaching rate. If pH < 9, the degree of amino acid protonation increases (–NH3). + The complexing ability decreases, and if the glycine concentration is too high, its protonated form may still bind some Ca²⁺. +However, it is very inefficient and consumes more Ca² + Reduce free Ca 2+ Supersaturation inhibits calcium carbonate nucleation and reduces aragonite production.

[0009] In step S3, the pH of the system at the end of the carbon dioxide mineralization reaction is 6-7; the initial pH of the leachate is 9-12, and a reaction occurs after CO2 is introduced: Ca 2+ + 2R-COO - (Amino acid radical) + CO2 + H2O → CaCO3↓ + 2R-COOH As CO2 is continuously absorbed and converted into CO3 2- / HCO3 - The pH of the system gradually decreases. When the pH drops to 6-7, it indicates that most of the Ca in the solution has been released. 2+ The product has been converted into CaCO3 precipitate, and CO2 absorption is close to equilibrium. Continued aeration no longer significantly produces products, therefore it can be used as a control parameter for the reaction endpoint. Under near-neutral conditions of pH 6-7, regenerated surfactants, such as amino acid molecules, exist in the form of R-COOH or zwitterions, and can selectively adsorb onto the high-energy crystal faces of aragonite crystals, reducing their surface energy and thus inhibiting the dissolution-recrystallization of aragonite into the thermodynamically more stable calcite. If the pH is too low (<6), the surfactant protonation is enhanced, the adsorption capacity decreases, and the acidic environment will promote the rapid dissolution of aragonite and its transformation into calcite; if the pH is too high (>7), most of the CaCO3 precipitate will be converted into calcite. 2+ It still exists in the form of an amino acid calcium complex and has not been completely converted into CaCO3; moreover, at high pH, ​​glycine is mainly anionic, which reacts with adsorbed OH groups. - Negatively charged surfaces experience electrostatic repulsion and cannot effectively adsorb onto the aragonite surface. Therefore, the solid obtained after solid-liquid separation is mainly amino acid calcium, rather than calcium carbonate.

[0010] Furthermore, in step S1, the alkaline activation solution is sodium hydroxide solution and / or ammonia; and / or, in step S2, the surfactant is an α-amino acid. Utilizing the amphoteric dissociation properties of α-amino acids, the pH of the system is adjusted to form a stable complex, reducing the concentration of free calcium ions and increasing the supersaturation of calcium ions in the system. This achieves efficient calcium leaching while laying the foundation for the formation of aragonite. During carbon dioxide mineralization, the regenerated α-amino acids adsorb onto specific crystal faces, effectively stabilizing the metastable phase of aragonite and inhibiting its transformation to the more thermodynamically stable calcite phase, thus achieving directional mineralization and stable growth of aragonite. The α-amino acids include at least one of glycine, aspartic acid, glutamic acid, and serine.

[0011] Furthermore, in step S1, the reaction temperature is 15~60℃; the solid-liquid ratio of the desulfurization ash to the alkaline activation solution is 1:2.5~1:10; the alkaline activation solution is a sodium hydroxide solution with a concentration of 3.5~5.0 mol / L.

[0012] Furthermore, in step S2, the concentration of the surfactant solution is 1.0~3.0 mol / L; and / or, the reaction time is 10~60 minutes.

[0013] Furthermore, in step S3, the carbon dioxide-containing gas is industrial exhaust gas or a CO2 gas source; the CO2 gas source is liquid or gaseous carbon dioxide with a purity ≥99.5%.

[0014] Furthermore, in the industrial exhaust gas, the CO2 volume fraction is ≥9%, the SO2 concentration is ≤100ppm, the NOx concentration is ≤200ppm, the H2S concentration is ≤50ppm, and the particulate matter concentration is ≤25mg / m³. 3 .

[0015] Furthermore, in step S3, the aeration rate corresponding to each liter of calcium ion leaching solution is 0.01~0.67 L / min; the system pH at the end of the mineralization reaction is determined by the CO2 introduction rate and reaction kinetics. If the aeration time is too short, the total amount of CO2 introduced will be insufficient, and the system pH can only drop to above 8. At this point, most of the Ca... 2+ It still exists in the form of amino acid calcium complexes and has not been completely converted into CaCO3; moreover, at high pH, ​​the amino acids are mainly anionic, which react with adsorbed OH groups. - Negatively charged surfaces experience electrostatic repulsion and cannot effectively adsorb onto the surface of aragonite. Therefore, the solid obtained after solid-liquid separation is mainly calcium amino acids, not calcium carbonate. If the aeration time is too long, the pH can drop below 6 (too acidic), but prolonged exposure to an acidic environment will cause the already formed aragonite to dissolve; at the same time, excessively protonated amino acids lose their selective adsorption capacity on the crystal faces of aragonite, which may instead induce the aragonite to transform into calcite.

[0016] Furthermore, the mineralized filtrate obtained from solid-liquid separation in step S3 can be used as part or all of the solvent to prepare the surfactant solution in step S2 and can be recycled.

[0017] The present invention also claims protection for a spheroidal calcium carbonate prepared by the above method, wherein the purity of the spheroidal calcium carbonate is >99%.

[0018] This invention also provides an application of the above-described method for preparing aragonite-type calcium carbonate in industrial solid waste resource utilization, carbon dioxide mineralization and capture, biomaterial preparation, or functional filler preparation.

[0019] The beneficial effects of this invention are: This invention pretreats desulfurization ash with NaOH / ammonia water, converting inactive calcium such as calcium sulfite and calcium carbonate into highly active Ca(OH)2, thus solving the problem of low calcium leaching rate in desulfurization ash. Simultaneously, through segmented precise pH control, the pH is maintained at 9-12 during the calcium leaching stage to ensure the proper interaction between α-amino acids and Ca. 2+ Highly efficient complexation; controlling pH 6-7 during the mineralization stage enables amino acid regeneration and adsorption of aragonite crystal faces, inhibiting the phase transition to calcite; in this invention, the α-amino acid has a dual-function regulation, acting as both a complexing agent to improve calcium leaching efficiency and a crystal form stabilizer to adsorb high-energy aragonite crystal faces, achieving high-purity aragonite preparation without the need for additional ammonia source; this method also allows for filtrate recycling, as the mineralization filtrate can be directly returned to the calcium leaching stage, realizing the recycling of surfactants and solvents and reducing costs. Attached Figure Description

[0020] Figure 1 This is the X-ray diffraction pattern of spheroidal calcium carbonate in Example 1 of the present invention; Figure 2 This is a scanning electron microscope image of spheroidal calcium carbonate from Example 1 of the present invention; Figure 3 This is the X-ray diffraction pattern of spheroidal calcium carbonate in Example 2 of the present invention; Figure 4 This is a scanning electron microscope image of spheroidal calcium carbonate from Example 2 of the present invention; Figure 5 This is the X-ray diffraction pattern of the solid product of Comparative Example 1 of the present invention; Figure 6 This is a scanning electron microscope image of the solid product of Comparative Example 1 of the present invention; Figure 7 This is the X-ray diffraction pattern of the solid product of Comparative Example 2 of the present invention; Figure 8 This is a scanning electron microscope image of the solid product of Comparative Example 2 of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this application. Obviously, the described embodiments are only some, not all, of the embodiments of this application. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0022] Unless otherwise specified, the raw materials, reagents or devices used in the following examples are available from conventional commercial sources or can be obtained by existing known methods.

[0023] It should be noted that the desulfurization ash used as raw material in the present invention is sourced from Handan Iron and Steel Group Co., Ltd.

[0024] Example 1: This embodiment provides a method for preparing high-purity spheroidal calcium carbonate using desulfurization ash as raw material, including the following steps: (1) Using sodium hydroxide as an alkaline activator, at room temperature of 25℃, the solid-liquid ratio of desulfurization ash and sodium hydroxide solution with a concentration of 5 mol / L was fixed at 1:5. Under alkaline activation, characteristic peaks such as calcium sulfite completely disappeared, and the desulfurization ash was almost completely converted into high-purity calcium hydroxide. The solid product of calcium hydroxide was obtained by filtration.

[0025] (2) Using glycine as a surfactant, a 2.0 mol / L glycine solution was added to the above solid product, and the mixture was leached at room temperature for 30 minutes. During this process, glycine exhibits its amphoteric dissociation properties, providing protons to buffer the pH of the system from extremely alkaline to approximately 10.5. At the same time, a large number of calcium ions were leached out and formed glycine-calcium complexes. The solid-liquid separation yielded a calcium leaching solution.

[0026] (3) Carbon dioxide gas was introduced into the calcium leaching solution at a flow rate of 0.08 L / min (based on a leaching volume of 1 L), and the mixture was stirred at a speed of 500 r / min during the reaction. The pH value of the system was monitored in real time. The reaction was stopped when the pH of the solution stabilized in the near-neutral range of about 6.8. The solution was filtered, washed, and dried to obtain aragonite-type calcium carbonate and filtrate.

[0027] X-ray diffraction tests were performed on the spherulite-type calcium carbonate obtained in Example 1. The X-ray diffraction results are as follows: Figure 1 As shown.

[0028] The spherulite-type calcium carbonate obtained in Example 1 was observed by scanning electron microscopy. The scanning electron micrograph is shown below. Figure 2 As shown.

[0029] according to Figure 1 By analyzing the data and performing quantitative phase calculations, the content of aragonite-type calcium carbonate was found to be 99.3%.

[0030] Depend on Figure 2 Scanning electron microscopy revealed that spheroidal calcium carbonate is mainly spherical, with a small number of near-spherical particles and aggregates of spherical particles.

[0031] Example 2: This embodiment provides a method for preparing aragonite-type calcium carbonate, including the following steps: (1) Using desulfurization ash as the calcium source and sodium hydroxide as the alkaline activator, the solid-liquid ratio of desulfurization ash to sodium hydroxide solution with a concentration of 4 mol / L was fixed at 1:10 at room temperature of 25℃. Under alkaline activation, the desulfurization ash was almost completely converted into high-purity calcium hydroxide, and the solid product of calcium hydroxide was obtained by filtration. (2) Using the filtrate obtained in Example 1 as the calcium leaching solution, the desulfurized ash after alkali activation treatment and the filtrate obtained in Example 1 were mixed and reacted at room temperature of 25 °C. When the pH reached 10, the reaction was stopped to obtain calcium ion leaching liquid. (3) Simulated flue gas was prepared on its own as a CO2 source, with a CO2 volume concentration of 15.0000%, an SO2 volume concentration of 0.0100%, and NO... x The volume concentration of H2S was 0.0200%, the volume concentration of O2 was 0.0050%, the volume concentration of N2 was 5.0000%, and the volume concentration of N2 was 79.9650%. The above-mentioned carbon dioxide-containing gas was introduced into the calcium ion leaching solution system obtained in step (2) at a flow rate of 0.08 L / min (based on a leaching solution volume of 1 L). The reaction was carried out at room temperature of 25℃. During the reaction, the stirring speed was maintained at 300 r / min. The pH value of the system was monitored in real time. When the pH of the solution system stabilized in the near-neutral range of about 6.8, the reaction was stopped, and the solution was filtered to obtain aragonite-type calcium carbonate and filtrate.

[0032] X-ray diffraction tests were performed on the spherulite-type calcium carbonate obtained in Example 2. The X-ray diffraction results are as follows: Figure 3 As shown.

[0033] The spherulite-type calcium carbonate obtained in Example 2 was observed by scanning electron microscopy. The scanning electron micrograph is shown below. Figure 4 As shown.

[0034] according to Figure 3 By analyzing the data and performing quantitative phase calculations, the content of aragonite-type calcium carbonate was found to be 99.2%.

[0035] Depend on Figure 4 Scanning electron microscopy reveals that spheroidal calcium carbonate is spherical.

[0036] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that the CO2 introduction time was adjusted so that the pH of the system at the end of the mineralization reaction was 8.5. Otherwise, they are the same as in Example 1.

[0037] X-ray diffraction tests were performed on the solid product obtained in Comparative Example 1. The X-ray diffraction results are as follows: Figure 5 As shown.

[0038] The solid product obtained in Comparative Example 1 was observed using a scanning electron microscope (SEM), and the SEM image is shown below. Figure 6 As shown.

[0039] according to Figure 5 and Figure 6 By combining the data analysis of the two, it was found that the solid product was calcium glycinate. That is, in the product obtained after the reaction with a small amount of carbon dioxide, only a small number of fine aragonite nuclei were formed. The majority of the product was calcium glycinate precipitated out due to the disruption of the balance of calcium glycinate ligands after the pH of the system decreased.

[0040] Depend on Figure 6 Scanning electron microscopy revealed that the calcium glycinate intermediate exhibited a fragmented structure with a small number of spheroidal calcium carbonate crystals on these structures.

[0041] Comparative Example 2 The only difference between Comparative Example 2 and Example 1 is that the surfactant glycine is not added in the S2 process of Comparative Example 2; otherwise, they are the same as in Example 1.

[0042] Comparative Example 2 yielded only a small amount of calcium carbonate product. X-ray diffraction analysis was performed on the obtained calcium carbonate, and the X-ray diffraction results are as follows: Figure 7 As shown.

[0043] The calcium carbonate obtained in Comparative Example 2 was observed using scanning electron microscopy. The scanning electron micrograph is shown below. Figure 8 As shown.

[0044] according to Figure 7 By analyzing the data and performing quantitative phase calculations, the calcite content was found to be 99.14%, meaning that the calcium carbonate product obtained after the reaction did not contain any aragonite-type calcium carbonate, but was entirely calcite-type calcium carbonate.

[0045] Depend on Figure 8 Scanning electron microscopy revealed that the calcium carbonate crystals were spindle-shaped calcite, consistent with the quantitative phase calculations.

[0046] In summary, the addition of surfactants can reduce the surface energy of aragonite crystals, inhibit the conversion to calcite, improve the purity of aragonite-type calcium carbonate, and enhance its stability. Furthermore, the filtrate obtained in this invention can be recycled back to step S2 as a calcium leaching solution.

[0047] Comparative Example 3 The difference from Example 1 is as follows: the concentration of glycine solution added in process S2 is reduced, and the CO2 introduction time in process S3 is adjusted so that the pH of the system at the end of the mineralization reaction is 5.5. Otherwise, it is the same as Example 1.

[0048] Results: When the glycine solution concentration was too low, the pH buffering capacity of glycine decreased. Excessive CO2 aeration time led to an excessive drop in the system pH to the acidic range (pH < 6), resulting in low formation of aragonite, which was easily soluble. Simultaneously, the dissolved Ca... 2+ Recrystallization forms thermodynamically more stable calcite, and the acidic environment weakens the complexation and coordination protection of glycine on the aragonite crystal faces. Therefore, the mineralization pH exceeds the optimal process window, resulting in reduced product purity.

[0049] Comparative Example 4 The difference from Example 1 is that the concentration of the glycine solution added during S2 is reduced, and the pH is controlled above 12 during the leaching process.

[0050] Results: Calcium leaching solution Ca 2+ The concentration was low. After CO2 was introduced into S3, the main product was calcite, with aragonite content <5%. This indicates that the glycine complexing ability decreases at high pH, ​​and Ca... 2+ Insufficient supersaturation.

[0051] Comparative Example 5 The difference from Example 1 is that the concentration of glycine solution added during S2 is increased, and the pH is controlled below 9 during leaching.

[0052] Result: Excess glycine will extensively chelate Ca. 2+ Reduce free Ca 2+ Supersaturation inhibits calcium carbonate nucleation and reduces aragonite yield. This indicates that calcium carbonate nucleation is difficult at low pH, leading to reduced aragonite yield and decreased glycine utilization.

[0053] Comparative Example 6 Compared with Example 1, the S1 alkaline activation step is omitted, and the desulfurized ash is directly mixed with glycine solution to leach calcium ions, while the other parameters remain unchanged.

[0054] Results: The calcium in the desulfurization ash has low activity and cannot be directly leached by glycine solution, resulting in a very low calcium leaching rate. No solid products were formed after carbon dioxide mineralization. The low activity of calcium in the desulfurization ash makes it impossible to leach; therefore, the pretreatment process of the desulfurization ash, through alkaline activation and treatment of calcium, is crucial.

[0055] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing high-purity aragonite using desulfurization ash as raw material, characterized in that, Includes the following steps: S1: The desulfurization ash is mixed with an alkaline activation solution, and after the reaction, solid-liquid separation is performed to obtain a solid product rich in calcium hydroxide. S2: Add a surfactant solution to the solid product obtained in step S1, react for a period of time, and then perform solid-liquid separation to obtain calcium ion leachate. S3: A carbon dioxide-containing gas is introduced into the calcium ion leachate obtained in step S2 to carry out a mineralization reaction. After the reaction is completed, solid-liquid separation, washing, and drying are performed to obtain aragonite-type calcium carbonate. In step S2, the pH of the system after the surfactant solution and solid product are mixed is 9-12; in step S3, the pH of the system at the end of the mineralization reaction is 6-7.

2. The method according to claim 1, characterized in that, In step S1, the alkaline activation solution is sodium hydroxide solution and / or ammonia; and / or, in step S2, the surfactant is an α-amino acid; the α-amino acid includes at least one of glycine, aspartic acid, glutamic acid, and serine.

3. The method according to claim 1, characterized in that, In step S1, the reaction temperature is 15~60℃; the solid-liquid ratio of the desulfurization ash to the alkaline activation solution is 1:2.5~1:10; the alkaline activation solution is a sodium hydroxide solution with a concentration of 3.5~5.0 mol / L.

4. The method according to claim 1, characterized in that, In step S2, the concentration of the surfactant solution is 1.0~3.0 mol / L; and / or, the reaction time is 10~60 minutes.

5. The method according to claim 1, characterized in that, In step S3, the carbon dioxide-containing gas is industrial exhaust gas or a CO2 gas source; the CO2 gas source is liquid or gaseous carbon dioxide with a purity of ≥99.5%.

6. The method according to claim 1, characterized in that, The industrial exhaust gas contains CO2 volume fraction ≥9%, SO2 concentration ≤100ppm, and NO... x Concentration ≤200ppm, H2S concentration ≤50ppm, particulate matter concentration ≤25mg / m³ 3 .

7. The method according to claim 1, characterized in that, In step S3, the aeration rate corresponding to each liter of calcium ion leachate is 0.01~0.67 L / min; the stirring speed is 200~500 rpm.

8. The method according to claim 1, characterized in that, The mineralized filtrate obtained from solid-liquid separation in step S3 can be used as part or all of the solvent to prepare the surfactant solution in step S2 and can be recycled.

9. A type of aragonite-type calcium carbonate, characterized in that, The calcium carbonate is prepared by the method according to any one of claims 1-8, and the purity of the aragonite-type calcium carbonate is >99%.

10. The method according to any one of claims 1-8 or the aragonite-type calcium carbonate according to claim 9 in the resource utilization of industrial solid waste, carbon dioxide mineralization and capture, preparation of biomaterials or preparation of functional fillers.

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