CO2 mineralization maintenance method and maintenance system for aerated building blocks coupled with power plant

Abstract

The invention discloses a CO2 mineralization maintenance method and maintenance system for aerated building blocks coupled with a power plant, and the CO2 mineralization maintenance method for aerated building blocks coupled with the power plant comprises the following steps: S1, introducing 180-200 DEG C waste heat steam of the power plant, and carrying out steam maintenance on the demolded building blocks; s2, CO2 gradient mineralization maintenance is conducted on the building blocks subjected to steam maintenance, and CO2 mineralization is divided into N-stage mineralization maintenance areas with the building block temperature decreasing in a gradient mode; the high-temperature building blocks subjected to steam curing sequentially enter the Nth-stage mineralization curing area from the first-stage mineralization curing area; the high-pressure CO2 is subjected to pressure reduction, then enters the waste heat recovery system to exchange heat with steam tail gas, sequentially enters each stage of mineralization maintenance area according to the sequence that the temperatures of the building blocks in the mineralization maintenance areas are from low to high to perform reverse mineralization reaction, and finally enters the waste heat recovery system after passing through the first stage of mineralization maintenance area. Compared with the prior art, the multi-stage mineralization maintenance area is matched with the reverse mineralization process, the CO2 utilization rate is effectively increased, compared with a traditional maintenance mode, the carbon maintenance cost is remarkably reduced, and energy conservation, emission reduction and production cost optimization are achieved.

Description

Technical Field

[0001] This invention belongs to the field of carbon mineralization utilization technology, specifically relating to a large-scale cascade mineralization maintenance system and method for aerated concrete blocks. Background Technology

[0003] Existing mineralization curing processes for porous building materials such as aerated concrete blocks and aerated concrete generally adopt a segmented system scheme of "high-temperature steam curing - carbon capture CO2 mineralization". This involves first using high-temperature steam curing to hydrate the cementitious material and form an initial structure, then transferring the product to a mineralization reaction space for CO2 permeation carbonization. However, in actual operation, this segmented system architecture has several systemic shortcomings: From a process connection perspective, the product after high-temperature steam curing needs to cool down slowly to reach the suitable temperature for carbonization, resulting in a prolonged curing cycle and significant heat loss during the transition, leading to low energy efficiency; from a reaction condition compatibility perspective, the high humidity and high temperature environment created by steam curing naturally conflicts with the low humidity and normal temperature conditions required for CO2 mineralization, causing a reduced CO2 diffusion rate within the product pores and limiting the depth of the carbonation reaction; from a system energy efficiency design perspective, the existing process has low energy utilization, making it difficult to meet the economic requirements of industrial production.

[0004] The root cause of the above problems lies in the lack of an integrated design for the "building material preparation-mineralization reaction-energy cycle" in existing system solutions, failing to construct a system that coordinates the curing process and heat recovery and utilization. With the urgent need for low-carbon and large-scale production in the building materials industry, there is an urgent need to reconstruct a new mineralization curing technology solution that integrates mineralization curing and energy recovery and utilization from a systems engineering perspective, so as to achieve synergistic optimization of CO2 fixation efficiency, building material performance improvement and system economy. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a CO2 mineralization curing method and system for aerated concrete blocks coupled with power plants, so as to solve the problem that the energy utilization rate of aerated concrete blocks and concrete blocks is low and the cost of secondary carbon curing cannot be reduced during the current CO2 mineralization curing process.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: This invention first provides a method for CO2 mineralization curing of aerated concrete blocks coupled with a power plant, comprising: S1. Connect to the power plant's 180-200℃ waste heat steam for steam curing of the demolded blocks; S2. CO2 graded mineralization curing of steam-cured blocks, including: S21. Divide CO2 mineralization into N-level mineralization curing zones with progressively decreasing block temperatures, where N≥2. The block temperature is highest in the first-level mineralization curing zone and lowest in the N-level mineralization curing zone. S22. After steam curing, the high-temperature blocks enter the Nth level mineralization curing zone sequentially from the first level mineralization curing zone. After depressurization, the high-pressure CO2 enters the waste heat recovery system and exchanges heat with the steam tail gas. Then, according to the block temperature in the mineralization curing zone from low to high, it enters each level mineralization curing zone sequentially for reverse mineralization reaction. Finally, after passing through the first level mineralization curing zone, it enters the waste heat recovery system. Reverse mineralization means that the flow direction of CO2 is opposite to the transport direction of the blocks.

[0007] The CO2 concentration varies in a tiered manner within each level of the N-level mineralization conservation zone, with the highest CO2 concentration in the N-level zone and the lowest in the 1-level zone; the CO2 pressure within each level of the mineralization conservation zone is below 0.1 MPa. During the CO2 cascade mineralization curing process, the CO2 concentration, pressure, and temperature in each mineralization curing zone are monitored in real time. Fans are used to accelerate gas flow and enhance heat exchange and reaction. When the CO2 pressure in each mineralization curing zone is lower than the preset value, CO2 is supplemented by a booster pump. When the gas pressure is higher than the set value, exhaust is performed through an exhaust device.

[0008] The CO2 concentration in the Nth-level mineralization conservation area is 80%, and the CO2 concentration in the first-level mineralization conservation area is 60%.

[0009] The CO2 pressure in each mineralization maintenance zone is 0.09 MPa.

[0010] The blocks remain in each mineralization curing zone for 8 hours, with a total curing time of 16 hours.

[0011] The present invention also provides a CO2 mineralization curing system for aerated concrete blocks coupled to a power plant, comprising: The steam curing device is connected to the waste heat steam at 180-200℃ from the power plant and is used for steam curing of the demolded blocks. CO2 gas cylinders are used to provide a CO2 gas source; A pressure reducing device is used to reduce the pressure of CO2 gas output from a CO2 cylinder; The waste heat recovery system includes a first heat exchange channel and a second heat exchange channel; The CO2 stepped mineralization curing device includes N-stage mineralization curing zones where the block temperature decreases in stages, N≥2. The block temperature is highest in the first-stage mineralization curing zone and lowest in the N-stage mineralization curing zone. After steam curing, the blocks undergo CO2 mineralization curing sequentially starting from the first-stage mineralization curing zone and finally entering the N-stage mineralization curing zone to complete the CO2 mineralization curing and form the finished product. Transport vehicle for transporting blocks, including feeding and sending blocks into and out of steam curing units, feeding and sending blocks into and out of CO2 cascade mineralization curing units, and moving blocks within steam curing units and CO2 cascade mineralization curing units. After depressurization, the CO2 gas enters the first flow channel of the waste heat recovery system; the low-temperature steam output from the steam curing device enters the second flow channel of the waste heat recovery system and exchanges heat with the CO2 gas before being discharged as tail gas; the depressurized CO2 gas exchanges heat with the low-temperature steam and then flows out at a higher temperature; the CO2 gas that flows out at a higher temperature enters the Nth stage mineralization curing zone of the CO2 cascade mineralization curing device in the opposite direction and finally exits from the 1st stage mineralization curing zone. The discharged CO2 tail gas then enters the first flow channel of the waste heat recovery system to participate in heat exchange.

[0012] The CO2 cascade mineralization curing device adopts a non-open-air pressurized curing room; the non-open-air pressurized curing room is divided into a curing area and a waiting area, the waiting area includes an inbound waiting area and an outbound waiting area, and the inbound and outbound of the non-open-air pressurized curing room are equipped with two isolation doors.

[0013] The non-open-air pressurized curing room adopts a steel structure frame, with rock wool insulation layers on the roof and four walls, and anti-slip concrete poured on the ground to form a sealed space. A fan system is installed in the sealed space to maintain stable internal air pressure. The sealed space is divided into a central curing area and two waiting areas for entering / exiting the curing room on each side. The fan system includes an air supply pump and an exhaust device. The air supply pump is linked to an emergency button. When the emergency button is activated, the air supply pump starts and all inlet and outlet doors open. The exhaust device is linked to the air pressure detection system in the curing room. When the air pressure in the curing room is higher than the set value, the exhaust device starts and shuts off when the air pressure reaches the preset value.

[0014] The non-open-air pressurized curing chamber adopts an air-supported membrane structure, which is a sealed space composed of high-strength flexible membrane material. A fan system is installed within the air-supported membrane structure to maintain stable internal air pressure. The interior is divided into a central curing area and two waiting areas for entry / exit on either side. The fan system includes an air supply pump and an exhaust device. The air supply pump is linked to an emergency stop button; when the emergency stop button is activated, the air supply pump starts and all inlet and outlet doors open. The exhaust device is linked to an air pressure detection system within the curing chamber; when the air pressure inside the curing chamber exceeds a set value, the exhaust device starts and closes when the pressure reaches the preset value.

[0015] The control method of the two isolation doors is as follows: when the product to be cured enters the curing room, the outer door is opened and the inner door is closed. After the product enters the warehousing waiting area, the outer door is closed first and then the inner door is opened to allow the product to enter the curing area. When the cured product leaves the curing room, the outer door is closed and the inner door is opened. After the product enters the outbound waiting area, the inner door is closed first and then the outer door is opened to allow the product to leave the curing room before the outer door is closed.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In the method described in this invention, the high-temperature blocks after steam curing exchange heat with the low-temperature CO2 generated in the first-stage curing process through a waste heat recovery system, achieving rapid cooling and pre-curing of the block surface. In the Nth-stage curing zone, the high-temperature CO2 generated by the waste heat recovery system is used to carbonize and cure the blocks, ensuring that the blocks are within the optimal curing temperature range. The multi-stage mineralization curing zones, combined with the reverse mineralization process, effectively improve CO2 utilization and significantly reduce carbon curing costs compared to traditional curing methods, achieving energy conservation, emission reduction, and production cost optimization.

[0017] 2. The method described in this invention reverse-couples the CO2 flow direction with the aerated concrete block running direction, achieving reverse matching between the CO2 temperature and the block temperature. After steam curing, the low-temperature CO2 comes into contact with the high-temperature block, completing rapid cooling and pre-carbonization, avoiding sudden temperature changes that could affect the block performance. In the later stages of curing, the high-temperature CO2 combines with the cooled block, achieving deep curing at the optimal temperature. This reverse coupling design enables cascaded energy utilization, improving energy efficiency, while significantly increasing the carbonization rate and depth, effectively enhancing the block strength and durability, and improving product quality.

[0018] 2. By setting up multi-level mineralization curing zones, the mineralization space of the blocks is increased, thereby expanding the scale of CO2 mineralization curing of aerated concrete blocks and concrete blocks. Through large-scale pressurized curing rooms and automated handling systems, large batches of blocks can be mineralized and cured simultaneously, increasing the residence time of blocks in the CO2 atmosphere and significantly enhancing the carbon fixation depth and strength.

[0019] 3. Improved adaptability of mineralization reaction conditions. By coupling steam curing with secondary carbon gradient curing, the inhibition of carbonate formation by the high temperature of traditional reactors is avoided, providing more suitable temperature conditions for mineralization reactions, and improving carbon fixation amount, carbon fixation depth, strength and curing efficiency.

[0020] 4. The pressure of the secondary carbon mineralization curing process has been increased, which solves the problems of low CO2 concentration and insufficient pressure in open or outdoor environments. The set pressure meets the requirements of pressure vessel regulations, which facilitates industrial implementation and further enhances the carbon sequestration effect.

[0021] 5. Improved safety in mineralization maintenance: The entire process adopts an intelligent control system and trackless flatbed transport vehicles. No personnel need to enter the maintenance room during operation, saving labor while ensuring the safety of operators. Attached Figure Description

[0022] Figure 1 This is a flowchart illustrating the CO2 mineralization curing method for aerated concrete blocks coupled with a power plant, as shown in the example. Figure 2Schematic diagram of CO2 curing area. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0024] The present invention will be further described in detail below with reference to the accompanying drawings. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0025] This embodiment provides a CO2 mineralization curing method for aerated concrete blocks coupled with a power plant, such as... Figure 1 As shown, the steps include: (1) Steam curing of the blocks after demolding: Steam curing can be performed using a steam curing kettle.

[0026] After the blocks are formed and demolded, they are transported by a transport vehicle to a steam curing autoclave for steam curing. The steam curing autoclave is connected to waste heat steam at 180-200 ℃ from the power plant. Steam curing is maintained for 4 hours, and the steam exhaust gas is connected to the waste heat recovery system through a pipeline.

[0027] (2) CO2 graded mineralization curing of steam-cured blocks: The CO2 cascade mineralization curing process divides the CO2 mineralization into N-level mineralization curing zones with progressively decreasing block temperatures, where N≥2. The block temperature is highest in the first-level mineralization curing zone and lowest in the N-level mineralization curing zone.

[0028] CO2 mineralization curing can be carried out using a pressurized curing chamber.

[0029] After steam curing, the high-temperature blocks are transported to a pressurized curing chamber, sequentially entering the Nth level of the mineralization curing zone from the first level. High-pressure CO2, after depressurization, enters the waste heat recovery system to exchange heat with the steam tail gas. Then, following the increasing block temperature within the mineralization curing zone, it enters each level of the mineralization curing zone for a reverse mineralization reaction, finally passing through the first level and entering the waste heat recovery system. Reverse mineralization means that the flow direction of CO2 is opposite to the transport direction of the blocks.

[0030] The waste heat recovery system uses a shell-and-tube heat exchanger with a heat exchange area of ​​50 m². 2 .

[0031] For CO2-based graded mineralization treatment, taking N=2 (secondary mineralization treatment) as an example, the specific process is as follows: 1. The high-pressure CO2 is reduced to 0.15 MPa by the pressure reducing device and enters the shell-and-tube heat exchanger, where it exchanges heat with the steam tail gas and the tail gas of the first stage curing area in a countercurrent manner to raise the temperature to 60 ℃. 2. The heated CO2 is sequentially introduced into the second-level curing zone (CO2 concentration 80%, block surface temperature 50-80 ℃) and the first-level curing zone (CO2 concentration 60%, block surface temperature 130-150 ℃), with each level lasting 4 hours, for a total curing time of 8 hours. The circulating fans in each maintenance area automatically adjust their frequency according to the CO2 concentration difference at each point (high frequency operation when the concentration difference is >10%, and low frequency operation when the concentration difference is <5%) to ensure uniform CO2 concentration distribution in the mineralized area.

[0032] This embodiment provides a CO2 mineralization curing system for aerated concrete blocks coupled to a power plant, comprising: A steam curing device is used for steam curing demolded blocks. A steam curing autoclave is an option for this device.

[0033] CO2 cylinders are used to provide a source of CO2 gas.

[0034] A pressure reducing device is used to reduce the pressure of CO2 gas output from a CO2 cylinder.

[0035] The waste heat recovery system includes a first heat exchange channel and a second heat exchange channel.

[0036] The CO2 stepped mineralization curing device includes N-stage mineralization curing zones where the block temperature decreases in stages, where N≥2. The block temperature is highest in the first-stage mineralization curing zone and lowest in the Nth-stage mineralization curing zone. After steam curing, the blocks undergo CO2 mineralization curing sequentially, starting from the first-stage zone and ending in the Nth-stage zone to complete the CO2 mineralization curing process and form the finished product.

[0037] Transport vehicles are used for transporting blocks, including feeding and discharging them into and out of steam curing units and CO2 cascade mineralization curing units.

[0038] The steam curing device, waste heat recovery system, and CO2 cascade mineralization curing device are coupled together. Specifically, the CO2 gas after depressurization enters the first flow channel of the waste heat recovery system; the low-temperature steam output from the steam curing device enters the second flow channel of the waste heat recovery system and exchanges heat with the CO2 gas before being discharged as tail gas; the depressurized CO2 gas exchanges heat with the low-temperature steam and then flows out at a higher temperature; the CO2 gas flowing out at a higher temperature enters the Nth stage mineralization curing zone of the CO2 cascade mineralization curing device in the reverse direction and finally exits from the 1st stage mineralization curing zone. The discharged CO2 tail gas then enters the first flow channel of the waste heat recovery system to participate in heat exchange.

[0039] To ensure the safety of the entire mineralization maintenance system, a safety assurance system is also included.

[0040] The security system includes: (1) Emergency ventilation device: air supply pump (air volume 20000 m³ / h) 3 The / h) is hardwired to an emergency button with a spacing of ≤30m. It will start within 0.5s after being triggered, and the entrance and exit gates will be fully opened within 10s. (2) Pressure balancing device: The pneumatic butterfly valve is linked with the pressure transmitter. When the pressure exceeds 0.11 MPa, it releases pressure at a rate of 0.005 MPa / s and closes when it reaches 0.09 MPa.

[0041] This invention, by coupling a steam curing device, a waste heat recovery system, and a CO2 cascade mineralization curing device, can significantly improve the efficiency, safety, and economy of CO2 mineralization curing. The relevant parameters of the steam curing device, waste heat recovery system, and CO2 cascade mineralization curing device can be adjusted according to actual production needs.

[0042] The CO2 cascade mineralization curing system employs a non-open-air pressurized curing chamber. The pressurized curing chamber can be configured in two structural forms: Structure Form 1: A steel frame structure is adopted, with a 100 mm rock wool insulation layer on the roof and four walls, and anti-slip concrete is poured on the ground to form a closed space of 70m long × 20m wide × 3m high. The interior is divided into a central curing area of ​​50m × 20m × 3m and two waiting areas of 10m × 20m × 3m on each side for entering / exiting the warehouse. Structure Form 2: It adopts an air-supported membrane space structure, which is made of high-strength flexible membrane material and equipped with a dedicated fan system to maintain stable internal air pressure. The space division is the same as that of Example 1.

[0043] The pressurized curing room has two steel isolation doors (4 m wide × 3 m high) at the entrance and exit. The doors are equipped with pneumatic door closers and sealing strips, and are interlocked and sealed through a PLC control system. (1) When the product is put into storage, the outer door opens after receiving the identification signal of the transport vehicle. After the product enters the storage waiting area, the outer door closes. The system detects the sealing performance through the pressure fluctuation threshold ≤0.001 MPa. After confirmation, the inner door is opened. (2) When products are shipped out, the inner door is opened when the maintenance is completed and there are no products left in the waiting area. After the products enter the outbound waiting area, the inner door is closed and the seal is checked. Then the outer door is opened to release the products.

[0044] The CO2 pressure (gauge pressure) in the curing room is controlled by a booster pump linked to a pressure detection system. (1) The inlet of the booster pump is connected to a 10 MPa high-pressure CO2 gas tank, and the outlet is connected to the gas supply pipeline on the top of the curing room through a pipeline; (2) Install pressure transmitters at the four corners and center of the curing room to collect pressure data in real time. When the pressure at any measuring point is lower than 0.085 MPa, the control cabinet triggers the booster pump to start until the pressure rises back to 0.09 MPa.

[0045] Product handling utilizes trackless flatbed trucks equipped with laser navigation and positioning capabilities. Through system-planned routes, fully automated transportation is achieved from the molding workshop → warehousing waiting area → designated storage location in the curing area → outbound waiting area → finished product warehouse.

[0046] The energy efficiency of this embodiment is calculated from an energy perspective, mainly comparing the difference in energy utilization between the normal maintenance scheme and this scheme. The calculation has been simplified to some extent.

[0047] Let the specific heat capacity of the block be c. qk =1.05kJ / (kg·K), mass m=100 kg, the initial temperature of the block after steam curing is T. ini =150 ℃, while the final temperature after mineralization curing is T fin =70 ℃.

[0048] The normal maintenance procedure involves an initial CO2 temperature of 25 ℃ and a specific heat capacity of c. CO2 =0.84 kJ / (kg·K), final temperature is 50 ℃; the initial temperature of CO2 in this scheme is 70 ℃, specific heat capacity c CO2 =0.84 kJ / (kg·K), final temperature is 100℃ Then calculate the heat release and heat absorption: Q = m·c·ΔT The required mass of CO2 is: m CO2 =Q / (c CO2 ·ΔT CO2 ) Logarithmic mean temperature difference: LMTD=(ΔT2-ΔT1) / ln(ΔT1 / ΔT2)

[0049] The data in the table show that the countercurrent curing scheme of this invention has a significantly lower CO2 requirement than the conventional curing scheme. Furthermore, since the calculation is based on the assumption of a pure CO2 environment, the dynamic adjustment of the concentration of the cascade curing in actual engineering will further reduce the CO2 requirement and significantly reduce equipment costs. Although the logarithmic mean temperature difference of the cocurrent scheme is larger, this scheme achieves deep matching of the temperature gradient through countercurrent design, avoids heat exchange dead zones, and has a higher outlet CO2 temperature and significantly improved energy quality, which can be directly used for secondary heating or waste heat recovery. It has outstanding advantages in consumable optimization, efficiency improvement and quality upgrade.

[0050] The above embodiments are merely illustrative examples of the present invention and do not limit its scope of protection. Those skilled in the art can make partial changes to them, as long as they do not exceed the spirit and essence of the present invention, they are all within the scope of protection of the present invention.

Claims

1. A method for CO2 mineralization curing of aerated concrete blocks coupled with a power plant, characterized in that, include: S1. Connect to the power plant's 180-200℃ waste heat steam for steam curing of the demolded blocks; S2. CO2 graded mineralization curing of steam-cured blocks, including: S21. Divide CO2 mineralization into N-level mineralization curing zones with progressively decreasing block temperatures, where N≥2. The block temperature is highest in the first-level mineralization curing zone and lowest in the N-level mineralization curing zone. S22. After steam curing, the high-temperature blocks enter the Nth level mineralization curing zone sequentially from the first level mineralization curing zone. After depressurization, the high-pressure CO2 enters the waste heat recovery system and exchanges heat with the steam tail gas. Then, according to the block temperature in the mineralization curing zone from low to high, it enters each level mineralization curing zone sequentially for reverse mineralization reaction. Finally, after passing through the first level mineralization curing zone, it enters the waste heat recovery system. Reverse mineralization means that the flow direction of CO2 is opposite to the transport direction of the blocks.

2. The CO2 mineralization curing method for aerated concrete blocks according to claim 1, characterized in that, The CO2 concentration varies in a tiered manner within each level of the N-level mineralization conservation zone, with the highest CO2 concentration in the N-level zone and the lowest in the 1-level zone; the CO2 pressure within each level of the mineralization conservation zone is below 0.1 MPa. During the CO2 cascade mineralization curing process, the CO2 concentration, pressure, and temperature in each mineralization curing zone are monitored in real time. Fans are used to accelerate gas flow and enhance heat exchange and reaction. When the CO2 pressure in each mineralization curing zone is lower than the preset value, CO2 is supplemented by a booster pump. When the gas pressure is higher than the set value, exhaust is performed through an exhaust device.

3. The CO2 mineralization curing method for aerated concrete blocks according to claim 2, characterized in that, The CO2 concentration in the Nth-level mineralization conservation area is 80-100%, while the CO2 concentration in the first-level mineralization conservation area is 40-60%.

4. The CO2 mineralization curing method for aerated concrete blocks according to claim 2, characterized in that, The CO2 pressure in each mineralization maintenance zone is 0.09 MPa.

5. The CO2 mineralization curing method for aerated concrete blocks according to claim 1, characterized in that, The blocks remain in each mineralization curing zone for 4-6 hours, with a total curing time of 8-12 hours.

6. A CO2 mineralization curing system for aerated concrete blocks coupled with a power plant, characterized in that, include: The steam curing device is connected to the waste heat steam at 180-200℃ from the power plant and is used for steam curing of the demolded blocks. CO2 gas cylinders are used to provide a CO2 gas source; A pressure reducing device is used to reduce the pressure of CO2 gas output from a CO2 cylinder; The waste heat recovery system includes a first heat exchange channel and a second heat exchange channel; The CO2 stepped mineralization curing device includes N-stage mineralization curing zones where the block temperature decreases in stages, N≥2. The block temperature is highest in the first-stage mineralization curing zone and lowest in the N-stage mineralization curing zone. After steam curing, the blocks undergo CO2 mineralization curing sequentially starting from the first-stage mineralization curing zone and finally entering the N-stage mineralization curing zone to complete the CO2 mineralization curing and form the finished product. Transport vehicle for transporting blocks, including feeding and sending blocks into and out of steam curing units, feeding and sending blocks into and out of CO2 cascade mineralization curing units, and moving blocks within steam curing units and CO2 cascade mineralization curing units. After depressurization, the CO2 gas enters the first flow channel of the waste heat recovery system; the low-temperature steam output from the steam curing device enters the second flow channel of the waste heat recovery system and exchanges heat with the CO2 gas before being discharged as tail gas; the depressurized CO2 gas exchanges heat with the low-temperature steam and then flows out at a higher temperature; the CO2 gas that flows out at a higher temperature enters the Nth stage mineralization curing zone of the CO2 cascade mineralization curing device in the opposite direction and finally exits from the 1st stage mineralization curing zone. The discharged CO2 tail gas then enters the first flow channel of the waste heat recovery system to participate in heat exchange.

7. A CO2 mineralization curing system for aerated concrete blocks coupled with a power plant, as described in claim 6, is characterized in that... The CO2 cascade mineralization curing device adopts a non-open-air pressurized curing room; the non-open-air pressurized curing room is divided into a curing area and a waiting area, the waiting area includes an inbound waiting area and an outbound waiting area, and the inbound and outbound of the non-open-air pressurized curing room are equipped with two isolation doors.

8. A CO2 mineralization curing system for aerated concrete blocks coupled with a power plant, as described in claim 7, is characterized in that... The non-open-air pressurized curing room adopts a steel structure frame, with rock wool insulation layers on the roof and four walls, and anti-slip concrete poured on the ground to form a sealed space. A fan system is installed in the sealed space to maintain stable internal air pressure. The sealed space is divided into a central curing area and two waiting areas for entering / exiting the curing room on each side. The fan system includes an air supply pump and an exhaust device. The air supply pump is linked to an emergency button. When the emergency button is activated, the air supply pump starts and all inlet and outlet doors open. The exhaust device is linked to the air pressure detection system in the curing room. When the air pressure in the curing room is higher than the set value, the exhaust device starts and shuts off when the air pressure reaches the preset value.

9. A CO2 mineralization curing system for aerated concrete blocks coupled with a power plant, as described in claim 7, is characterized in that... The non-open-air pressurized curing chamber adopts an air-supported membrane structure, which is a sealed space composed of high-strength flexible membrane material. A fan system is installed within the air-supported membrane structure to maintain stable internal air pressure. The interior is divided into a central curing area and two waiting areas for entry / exit on either side. The fan system includes an air supply pump and an exhaust device. The air supply pump is linked to an emergency stop button; when the emergency stop button is activated, the air supply pump starts and all inlet and outlet doors open. The exhaust device is linked to an air pressure detection system within the curing chamber; when the air pressure inside the curing chamber exceeds a set value, the exhaust device starts and closes when the pressure reaches the preset value.

10. A CO2 mineralization curing system for aerated concrete blocks coupled with a power plant, as described in claim 6, is characterized in that... The control method of the two isolation doors is as follows: when the product to be cured enters the curing room, the outer door is opened and the inner door is closed. After the product enters the warehousing waiting area, the outer door is closed first and then the inner door is opened to allow the product to enter the curing area. When the cured product leaves the curing room, the outer door is closed and the inner door is opened. After the product enters the outbound waiting area, the inner door is closed first and then the outer door is opened to allow the product to leave the curing room before the outer door is closed.

Images