Integrated carbon sequestration method and device for scraper drying crystallizer

Abstract

The invention discloses an integrated carbon sequestration method and device for a scraper drying crystallizer, and relates to the technical field of environment-friendly processes and equipment.The integrated carbon sequestration method comprises the steps that nanoscale alkaline mineral powder is added into waste water to form a mixed solution, and then the mixed solution is guided into an evaporative crystallization chamber of the scraper drying crystallizer. Alkaline mineral powder is introduced into a scraper drying crystallizer integrated carbon sequestration device, and is coordinated with vacuum and low-temperature environments and matched with a gas-liquid-solid three-phase turbulent flow environment formed by a centrifugal force field, so that dissolved-state CO escapes at low temperature and is subjected to mineralization reaction with the nanoscale alkaline mineral powder, stable carbonate precipitates are generated, and carbon sequestration is formed; and carbon sequestration and wastewater treatment are completed synchronously. According to the invention, COs as waste gas are converted into resources for utilization, and additional carbon capture and storage technologies are not needed.

Description

Technical Field

[0001] This invention relates to the field of environmental protection technology and equipment, and in particular to an integrated carbon sequestration method and apparatus for a scraper dryer crystallizer. Background Technology

[0002] Wastewater containing N6 (caprolactam) and N66 (adipic acid, hexamethylenediamine) with COD > 12000 mg / L generated by the spray system in the production workshop is pretreated and then treated by a special integrated low-temperature evaporation-scraped crystallization equipment (such as CN221217261U).

[0003] The wastewater containing N6 and N66 is guided to the evaporation and crystallization chamber of a special equipment. The evaporation and crystallization chamber maintains a vacuum negative pressure environment of -90 kPa through a negative pressure system to lower the boiling point of the mixture. Then, the mixed wastewater stirred by the scraper is heated to 40°C by steam or other heating media in the jacket cavity outside the evaporation and crystallization chamber for evaporation and crystallization. The evaporated gas is drawn out by the negative pressure system.

[0004] Since the COD values ​​in the wastewater all exceed 10,000, it indicates that the wastewater contains a large amount of organic pollutants. The carbon dioxide (CO2) generated by the neutralization reaction in the pretreatment exists in the N6 / N66 wastewater in a dissolved state (molecular and combined state). It escapes during negative pressure evaporation due to Henry's Law. CO2 is captured and stored by professional carbon capture. Summary of the Invention

[0005] One of the objectives of this invention is to solve the problem that CO2 escape during negative pressure evaporation in existing processes requires external carbon capture equipment for containment.

[0006] The second objective of this invention is to provide an integrated carbon sealing device for a scraper dryer crystallizer.

[0007] To achieve one of the above objectives, the present invention adopts the following technical solution: a method for integrated carbon sequestration in a scraper dryer crystallizer, comprising the following steps: S1 adds nano-sized alkaline mineral powder to wastewater with COD≥3000mg / L to form a mixed solution.

[0008] S2 introduces the mixture into the evaporation and crystallization chamber of the scraper dryer crystallizer, and applies a centrifugal shear force field to the mixture under a negative pressure environment of -95kPa to -80kPa to form a gas-liquid-solid three-phase turbulent environment.

[0009] Within a temperature range of 40-50℃, S3 induces dissolved CO2 in the mixture to escape and react with alkaline mineral powder to form carbonate precipitates, thereby achieving carbon sequestration.

[0010] COD ≥ 3000 mg / L covers potential alternatives (such as chemical and pharmaceutical wastewater).

[0011] The system consists of three phases: gas, liquid, and solid. The gas is CO2, the liquid is a mixture, and the solid is unreacted nano-sized alkaline mineral powder or carbonate precipitates generated by mineralization reactions.

[0012] The beneficial effects of this invention are: Transform the vacuum and cryogenic environment into conditions favorable for CO2 encapsulation processes.

[0013] The core advantage of this invention lies in the introduction of alkaline mineral powder into the carbon sequestration device integrated into the scraper dryer crystallizer. Combined with the synergistic effect of vacuum and low-temperature environment, and the gas-liquid-solid three-phase turbulent environment created by centrifugal force, dissolved CO2 is forced to escape at low temperature (40-50℃) and undergo a mineralization reaction with the nano-sized alkaline mineral powder, generating stable carbonate precipitates and forming carbon sequestration. Carbon sequestration and wastewater treatment are completed simultaneously. This invention converts CO2, which is considered waste gas, into a resource for utilization, eliminating the need for additional carbon capture and sequestration technologies.

[0014] Furthermore, in this embodiment of the invention, in step S1, the particle size of the nano-sized alkaline mineral powder is controlled at 20-100 nm, its specific surface area is >50 m² / g, and it has been modified by a silane coupling agent.

[0015] Furthermore, in this embodiment of the invention, in step S3, the heat released by the mineralization reaction is absorbed by the phase change material layer, and the absorbed and stored heat is directionally released to the mixture for heating.

[0016] Furthermore, in this embodiment of the invention, the phase change material layer is composed of a fatty acid eutectic and a thermal conductivity enhancer, with a phase change temperature and a mineralization reaction temperature difference of ≤5℃ and a latent heat density of ≥180kJ / kg. The thermal conductivity enhancer is graphene nanosheets or silicon carbide whiskers, with a mass ratio of 5-15%.

[0017] Furthermore, in this embodiment of the invention, in step S2, the relationship between the boiling point of the mixture and the vacuum negative pressure generally follows the Clausius-Clapeyron equation, thereby controlling and achieving a dynamic balance between the CO2 escape rate and the mineralization rate.

[0018] Furthermore, in this embodiment of the invention, in step S2, the centrifugal shear force field is achieved by the stirring action of the rotating scraper, and the intensity of the centrifugal shear force field is 80-180G.

[0019] To achieve the second objective mentioned above, the present invention adopts the following technical solution: a scraper dryer crystallizer integrated carbon sealing device for implementing the method described in one of the objectives of the invention, comprising a buffer container, a scraper dryer crystallizer and a vacuum maintaining device, wherein a rotating scraper is provided in the evaporation crystallization chamber of the scraper dryer crystallizer, and an alkaline substance addition module connected to the buffer container is configured to inject nano-sized alkaline mineral powder into the mixture.

[0020] The evaporation and crystallization chamber is maintained at a negative pressure environment of -95 kPa to -80 kPa by a vacuum maintenance device.

[0021] The rotating scraper applies a centrifugal shear force field to the mixture of the liquid and the nano-sized alkaline mineral powder through a stirring action.

[0022] The evaporation crystallization chamber is maintained at a temperature range of 40-50°C by a heating medium located in the jacket cavity outside the chamber.

[0023] Furthermore, in this embodiment of the invention, the inner wall of the jacket cavity is coated with a phase change material layer using plasma spraying technology, with a coating thickness of 12 mm and a latent heat of phase change ≥180 kJ / kg.

[0024] Furthermore, in this embodiment of the invention, the alkaline substance addition module includes a screening unit and a powder diffusion unit.

[0025] Furthermore, in this embodiment of the invention, the upper end of the screening unit is a cylindrical body with screening holes, which is housed in the powder storage cylinder of the alkaline substance addition module. The upper end of the screening unit is a cylindrical body with a toothed belt, which is rotatably connected to the powder storage cylinder.

[0026] The powder diffusion unit consists of a conical guide column and a conical diffusion seat. The conical guide column passes through the screening unit from bottom to top. The conical guide column is provided with a guide groove that matches the screening hole to guide the alkaline mineral powder passing through the screening hole into the conical diffusion seat.

[0027] The conical diffuser seat is provided with material drop ring grooves at different heights along its conical surface, thereby forming a stepped material drop position structure. Each of the material drop ring grooves is provided with a discharge hole that extends to the bottom of the conical diffuser seat.

[0028] An oscillator is installed at the bottom of the conical diffuser. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of an integrated carbon sealing device for a scraper dryer crystallizer according to an embodiment of the present invention.

[0030] Figure 2 This is a three-dimensional structural diagram of the alkaline substance addition module in an embodiment of the present invention.

[0031] Figure 3 This is a three-dimensional structural diagram of the conical diffuser seat according to an embodiment of the present invention.

[0032] 1. Buffer container; 2. Scraped dry crystallizer; 2.1. Jacketed cavity; 3. Vacuum maintenance device; 4. Alkaline substance addition module. 5. Screening unit; 6. Toothed belt; 10. Powder diffusion unit; 11. Conical guide column; 12. Conical diffuser seat; 13. Material drop ring groove. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clear and complete, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some, not all, embodiments of the present invention, and are merely illustrative of the embodiments of the present invention. They are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] In the description of this invention, it should be noted that the terms "center," "middle," "upper," "lower," "left," "right," "inner," "outer," "top," "bottom," "side," "vertical," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "a," "first," "second," "third," "fourth," "fifth," and "sixth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] For purposes of simplicity and illustration, the principles of the embodiments are described primarily by way of example. In the following description, numerous specific details are set forth to provide a thorough understanding of the embodiments. However, it will be apparent to those skilled in the art that these embodiments may not be limited to these specific details in practice. In some instances, well-known scraper dryer crystallizer integrated carbon sequestration methods and structures have not been described in detail to avoid unnecessarily obscuring these embodiments. Furthermore, all embodiments can be used in combination with each other. Example 1

[0037] It should be noted that the accompanying drawings are part of the content of the instruction manual. The structural shapes, connections, fits, and positional relationships that can be clearly seen in the accompanying drawings should all be understood as part of the content of the instruction manual.

[0038] A method for integrating carbon storage in a scraper dryer crystallizer 2 includes the following steps: S1 adds nano-sized alkaline mineral powder to wastewater with COD≥3000mg / L to form a mixed solution.

[0039] S2 introduces the mixture into the evaporation and crystallization chamber of the scraper dryer crystallizer 2, and applies a centrifugal shear force field to the mixture under a negative pressure environment of -95kPa to -80kPa to form a gas-liquid-solid three-phase turbulent environment.

[0040] Within a temperature range of 40-50℃, S3 induces dissolved CO2 in the mixture to escape and react with alkaline mineral powder to form carbonate precipitates, thereby achieving carbon sequestration.

[0041] COD ≥ 3000 mg / L covers potential alternatives (such as chemical and pharmaceutical wastewater).

[0042] The system consists of three phases: gas, liquid, and solid. The gas is CO2, the liquid is a mixture, and the solid is unreacted nano-sized alkaline mineral powder or carbonate precipitates generated by mineralization reactions.

[0043] The core advantage of this invention lies in the introduction of alkaline mineral powder into the carbon sequestration device integrated into the scraper dryer crystallizer. Combined with the synergistic effect of vacuum and low-temperature environment, and the gas-liquid-solid three-phase turbulent environment created by centrifugal force, dissolved CO2 is forced to escape at low temperature (40-50℃) and undergo a mineralization reaction with the nano-sized alkaline mineral powder, generating stable carbonate precipitates and forming carbon sequestration. Carbon sequestration and wastewater treatment are completed simultaneously. This invention converts CO2, which is considered waste gas, into a resource for utilization, eliminating the need for additional carbon capture and sequestration technologies.

[0044] The specific advantages of this invention are that the vacuum negative pressure environment not only lowers the boiling point of the mixture to avoid secondary decomposition of organic matter and generation of CO2 caused by high temperature (>80°C), but also significantly improves the CO2 mass transfer rate through Henry's Law, thereby effectively improving carbon sequestration efficiency.

[0045] Henry's Law applies: Under negative pressures ranging from -95 kPa to -80 kPa, the solubility of CO2 in the liquid phase decreases to 0.02 g / L (1.45 g / L at normal pressure), forcing dissolved CO2 to migrate rapidly into the gas phase, thus increasing its escape efficiency.

[0046] The specific advantages of this invention are that the shear force field not only increases the contact area between CO2 and alkaline mineral powder, but also breaks up the agglomeration of alkaline mineral powder as a mechanical action, continuously exposing active sites, thereby increasing the mineralization reaction rate and effectively improving carbon sequestration efficiency.

[0047] The specific advantage of this invention is that the generated carbonate can be used as a filler in building materials, forming a closed-loop carbon cycle.

[0048] Specifically, in step S1, the particle size of the nano-sized alkaline mineral powder is controlled at 20-100 nm, its specific surface area is >50 m² / g, and it has been modified by a silane coupling agent.

[0049] The silane coupling agent (KH-550) forms -Si-O-Mg / Ca bonds on the powder surface, reducing the surface energy and improving the uniformity of powder dispersion in the liquid phase.

[0050] Nanoscale alkaline mineral powder contains either calcium oxide (CaO) or magnesium oxide (MgO).

[0051] Calcium oxide (CaO) reacts with CO2: CaO + CO2 = CaCO3, rapidly generating calcium carbonate (CaCO3) precipitate, thus achieving the mineralization and sequestration of CO2.

[0052] Magnesium oxide (MgO) reacts with CO2: MgO + CO2 = MgCO3, and the resulting magnesium carbonate (MgCO3) precipitate can seal CO2 for a long time at room temperature. Both calcium carbonate and magnesium carbonate are carbonates.

[0053] The mass ratio of nano-sized alkaline mineral powder to the mixed liquid is 0.35%-0.45%.

[0054] Specifically, in step S3, the phase change material layer absorbs the heat released by the mineralization reaction and releases the absorbed and stored heat directionally to the mixture to raise its temperature.

[0055] The advantage of this invention is that the mineralization reaction is an exothermic process, and the released heat is absorbed by the phase change material and reused to maintain the evaporation temperature (40-50℃), reducing the external steam demand. The phase change material layer achieves thermal energy self-balance during the evaporation and crystallization process by absorbing the exothermic reaction and releasing the stored heat energy, thus improving the temperature fluctuation problem caused by intermittent feeding.

[0056] More specifically, the phase change material layer is composed of fatty acid eutectic and thermal conductivity enhancer. The difference between its phase change temperature and mineralization reaction temperature is ≤5℃, and its latent heat density is ≥180kJ / kg. The thermal conductivity enhancer is graphene nanosheets or silicon carbide whiskers, accounting for 5-15% by mass.

[0057] Specifically, in step S2, the relationship between the boiling point of the mixture and the vacuum negative pressure usually follows the Clausius-Clapeyron equation, thereby controlling and achieving a dynamic balance between the CO2 escape rate and the mineralization rate.

[0058] By adjusting the vacuum level (e.g., controlling the power of the vacuum maintaining device 3), the boiling point of the mixture can be changed in real time (e.g., from 40°C to 50°C), thereby controlling the CO2 escape rate. Simultaneously, combined with the enhancing effect of the shear force field on the mineralization reaction (shortening the mixing time), a dynamic balance between the escape rate and the mineralization rate can be achieved.

[0059] CO2 and vacuum level can be detected using existing sensors.

[0060] By controlling the boiling point of the mixture through real-time adjustment of vacuum negative pressure and regulating the CO2 escape rate using the Clausius-Clapeyron equation, while simultaneously enhancing the contact probability between alkaline mineral powder and CO2 using a centrifugal force field, the mineralization reaction rate is matched with the escape rate. This avoids the need for additional steam to maintain the temperature and increase energy consumption when the CO2 escape rate is too high (due to increased vacuum); and also avoids material waste and increased solid waste treatment costs when the mineralization reaction rate is insufficient (due to excessive alkaline powder).

[0061] Specifically, in step S2, the centrifugal shear force field is achieved by the stirring action of the rotating scraper, and the intensity of the centrifugal shear force field is 80-180G. Example 2

[0062] An integrated carbon sealing device for a scraper dryer crystallizer 2 used to implement the method in Example 1, such as Figure 1 As shown, it includes a buffer container 1, a scraper dryer crystallizer 2, and a vacuum maintaining device 3. The evaporation crystallizer 2 is equipped with a rotating scraper in its evaporation crystallization chamber. The alkaline substance addition module 4, which is connected to the buffer container 1, is configured to inject nano-sized alkaline mineral powder into the mixture.

[0063] The evaporation crystallization chamber is maintained at a negative pressure environment of -95kPa to -80kPa by the vacuum maintenance device 3.

[0064] The rotating scraper applies a centrifugal shear force field to the mixture of the liquid and the nano-sized alkaline mineral powder through a stirring action.

[0065] The evaporation crystallization chamber is maintained at a temperature range of 40-70°C by the heating medium in the jacket cavity 2.1 located outside it.

[0066] Specifically, the inner wall of the jacket cavity 2.1 is coated with a phase change material layer using plasma spraying technology, with a coating thickness of 12mm and a latent heat of phase change ≥180kJ / kg.

[0067] During operation, COD wastewater exceeding 3000 mg / L first enters the buffer container 1. The alkaline substance addition module 4 injects nano-sized alkaline mineral powder (CaO / MgO, specific surface area 58 m² / g) into the mixed liquid at a mass ratio of 0.4%. The silane coupling agent-modified powder forms a stable suspension system in the liquid phase. The mixed liquid is pumped into the evaporation and crystallization chamber of the scraped dryer crystallizer 2. The vacuum maintenance device 3 controls the pressure inside the chamber at -85 kPa. This negative pressure environment lowers the boiling point of the mixed liquid to 48°C, and reduces the Henry's constant of dissolved CO2 to 0.015 mol / (m³·kPa). CO2 rapidly escapes from the liquid phase, forming micron-sized bubbles. Driven by a rotating scraper at 320 rpm, the blade surface generates a 120G centrifugal force field, compressing the liquid film thickness to below 0.2 mm. Unreacted nano-sized alkaline mineral powder and CO2 bubbles collide violently under the strong shearing action generated by the rotating scraper, causing them to break down and expanding the gas-solid contact area. CaO preferentially reacts with CO2 to form CaCO3, releasing heat (-178 kJ / mol). The released heat is absorbed and stored by the phase change material layer (12 mm thick, latent heat 192 kJ / kg) in the jacket cavity 2.1. When the low-temperature mixed liquid (25℃) enters, the phase change material begins to release heat at 45℃, stabilizing the temperature of the evaporation crystallization chamber at 45±2℃, reducing the need for external steam replenishment. Finally, the mineralized CaCO3 / MgCO3 particles (particle size 2-5 μm) are discharged with the dried crystals and can be directly used as concrete admixtures, achieving simultaneous carbon sequestration and wastewater treatment.

[0068] The system consists of three phases: gas, liquid, and solid. The gas is CO2, the liquid is a mixture, and the solid is unreacted nano-sized alkaline mineral powder or carbonate precipitates generated by mineralization reactions.

[0069] The core advantage of this invention lies in the introduction of alkaline mineral powder into the carbon sequestration device integrated into the scraper dryer crystallizer. Combined with the synergistic effect of vacuum and low-temperature environment, and the gas-liquid-solid three-phase turbulent environment created by centrifugal force, dissolved CO2 is forced to escape at low temperature (40-50℃) and undergo a mineralization reaction with the nano-sized alkaline mineral powder, generating stable carbonate precipitates and forming carbon sequestration. Carbon sequestration and wastewater treatment are completed simultaneously. This invention converts CO2, which is considered waste gas, into a resource for utilization, eliminating the need for additional carbon capture and sequestration technologies.

[0070] The specific advantages of this invention are that the vacuum negative pressure environment not only lowers the boiling point of the mixture to avoid secondary decomposition of organic matter and generation of CO2 caused by high temperature (>80°C), but also significantly improves the CO2 mass transfer rate through Henry's Law, thereby effectively improving carbon sequestration efficiency.

[0071] The specific advantages of this invention are that the shear force field not only increases the contact area between CO2 and alkaline mineral powder, but also breaks up the agglomeration of alkaline mineral powder as a mechanical action, continuously exposing active sites, thereby increasing the mineralization reaction rate and effectively improving carbon sequestration efficiency.

[0072] The specific advantage of this invention is that the generated carbonate can be used as a filler in building materials, forming a closed-loop carbon cycle. Example 3

[0073] This embodiment provides a device that differs from Embodiment 2, such as... Figure 2 As shown, the alkaline substance addition module 4 of the device includes a screening unit 5 and a powder diffusion unit 10.

[0074] More specifically, such as Figure 2 , Figure 3 As shown, the upper end of the screening unit 5 is a cylinder with screening holes, which is housed in the powder storage cylinder of the alkaline substance addition module 4. The upper end of the screening unit 5 is a cylinder with a toothed belt 6, which is rotatably connected to the powder storage cylinder.

[0075] The powder diffusion unit 10 consists of a conical guide column 11 and a conical diffuser seat 12. The conical guide column 11 passes through the screening unit 5 from bottom to top. The conical guide column is provided with a guide groove that matches the screening hole to guide the alkaline mineral powder passing through the screening hole into the conical diffuser seat 12.

[0076] The conical diffuser seat 12 is provided with material drop ring grooves 13 at different heights along its conical surface, thereby forming a stepped material drop position structure. Each material drop ring groove 13 is provided with a discharge hole that extends to the bottom of the conical diffuser seat 12.

[0077] An oscillator is installed at the bottom of the conical diffuser seat 12, and the rest is the same as in embodiment 2.

[0078] In use, the rack belt 6 driven by the motor drives the rotary screening unit 5 to rotate. The alkaline mineral powder (such as CaO / MgO) in the powder storage cylinder is classified by particle size through the screening holes of the rotary screening unit 5. Particles with a particle size >100nm are intercepted, and the qualified nano-sized alkaline mineral powder (20-100nm) passes through the screening holes to enter the next stage.

[0079] The combination of screening holes and rotation can physically break up agglomerates of powder formed by electrostatic or van der Waals forces, ensuring the dispersibility of alkaline mineral powder.

[0080] When the screening hole corresponds to the guide groove, the alkaline mineral powder falls along the guide groove onto the conical diffuser seat 12; otherwise, it forms a seal on the screening hole.

[0081] By controlling the rotation speed of the screening unit 5 (e.g., 10-60 rpm), the alignment frequency between the guide groove and the screening hole is adjusted, thereby regulating the rate of adding alkaline mineral powder.

[0082] The staggered sealing design prevents the mixture from back-seeping into the powder storage cylinder, thus avoiding the powder from absorbing moisture and clumping.

[0083] The screened alkaline mineral powder falls along the guide groove of the conical guide column 11 and enters the conical diffuser seat 12. The powder is dispersed step by step through the discharge ring grooves 13 at different heights of the conical diffuser seat 12. The discharge holes of each stage of the discharge ring groove 13 are evenly distributed along the circumference, realizing the multi-path and multi-angle addition of powder in the mixture.

[0084] The oscillator at the bottom of the diffuser prevents the discharge hole from being blocked by the powder due to moisture absorption or electrostatic adsorption, while also enhancing the uniformity of powder diffusion in the mixture.

[0085] When the powder falls into the mixture through the discharge hole, -Si-O-Mg / Ca bonds are formed on the surface of the powder modified by the silane coupling agent, which reduces the surface energy and further promotes the stable suspension of the powder in the liquid phase.

[0086] The advantages are: through the synergistic design of dynamic screening, acceleration rate control, step-by-step dispersion and oscillation anti-clogging, the efficient dispersion, precision and anti-clogging of nano-sized alkaline mineral powder are achieved, ensuring the dynamic balance between the mineralization reaction rate and the CO2 escape rate, so that the device can operate continuously.

[0087] Although the illustrative specific embodiments of the present invention have been described above to enable those skilled in the art to understand the invention, the invention is not limited to the scope of the specific embodiments. For those skilled in the art, all inventions utilizing the concept of the present invention are protected as long as various variations are within the spirit and scope of the invention as defined and determined by the appended claims.

Claims

1. A method of integrated carbon sequestration for a scraped surface drying crystallizer characterized by, The method comprises the following steps: S1: adding nano-sized alkaline mineral powder into wastewater with COD≥3000mg / L to form a mixed solution; S2: introducing the mixed solution into an evaporation crystallization chamber of a scraper drying crystallizer, and applying a centrifugal shear force field to the mixed solution under a negative pressure environment of-95kPa to-80kPa to form a gas-liquid-solid three-phase turbulent flow environment; S3: inducing dissolved carbon dioxide in the mixed solution to escape and react with the alkaline mineral powder to generate carbonate precipitate and realize carbon sequestration at a temperature of 40-50℃; In step S2, the relationship between the boiling point of the mixed solution and the vacuum negative pressure follows the Clausius-Clapeyron equation to control the dynamic balance between the carbon dioxide escape rate and the mineralization rate.

2. The method of claim 1, wherein, In step S1, the particle size of the nano-sized alkaline mineral powder is controlled to be 20-100nm, the specific surface area is >50m² / g, and the nano-sized alkaline mineral powder is modified by a silane coupling agent.

3. The method of claim 1, wherein, In step S3, a phase change material layer is used to absorb the heat released by the mineralization reaction and release the absorbed and stored heat to the heating process of the mixed solution.

4. The method of claim 3, wherein, The phase change material layer is composed of a fatty acid eutectic compound and a heat conduction enhancer, the phase change temperature difference with the mineralization reaction temperature is ≤5℃, and the latent heat density is ≥180kJ / kg, and the heat conduction enhancer is graphene nanosheet or silicon carbide whisker with a mass ratio of 5-15%.

5. The method of claim 1, wherein, In step S2, the centrifugal shear force field is realized by the stirring action of the rotating scraper, and the centrifugal shear force field strength is 80-180G.

6. A wiper-drier crystallizer integrated carbon sequestration apparatus for carrying out the method of any one of claims 1-5, comprising a buffer vessel, a wiper-drier crystallizer having a rotating wiper inside its evaporative crystallization chamber, and a vacuum maintenance apparatus, characterized in that, An alkaline substance adding module connected with the buffer container is configured to inject nano-sized alkaline mineral powder into the mixed solution; The evaporation crystallization chamber is maintained in a negative pressure environment of-95kPa to-80kPa by a vacuum maintaining device; The rotating scraper applies a centrifugal shear force field to the mixed solution and the nano-sized alkaline mineral powder mixed solution through stirring action; The evaporation crystallization chamber is maintained in a temperature range of 40-50℃ by a heating medium in a jacket cavity arranged outside the evaporation crystallization chamber; The alkaline substance adding module comprises a screening unit and a powder diffusion unit; The upper end of the screening unit is a cylinder body provided with screening holes and accommodated in a powder storage cylinder of the alkaline substance adding module, and the upper end of the screening unit is a cylinder body provided with a rack strip and rotationally connected with the powder storage cylinder; The powder diffusion unit comprises a conical flow guide column and a conical diffusion seat, the conical flow guide column penetrates the screening unit from bottom to top, the conical flow guide is provided with a guide groove matched with the screening hole to guide the alkaline mineral powder passing through the screening hole to fall into the conical diffusion seat; The conical diffusion seat is provided with a material falling ring groove at different heights along the conical surface to form a stepped material falling position structure, and each material falling ring groove is provided with a discharge hole penetrating to the bottom of the conical diffusion seat; The bottom of the conical diffusion seat is provided with an oscillator.

7. The wiper-drier crystallizer integrated carbon sequestration apparatus of claim 6, wherein, The inner wall of the jacket cavity is coated with a phase change material layer by plasma spraying technology, the coating thickness is 12mm, and the phase change latent heat is ≥180kJ / kg.

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