A CO2-cured carbon-fixed lightweight wall panel system and its preparation method

Abstract

The application relates to the technical field of carbon dioxide mineralization building material manufacturing, and discloses a CO2 pressurized curing carbon fixation light wallboard system and a preparation method.The system comprises a pulp preparation and pre-curing module, a gas injection and mineralization module, a dehumidification and gas circulation loop and a waste heat recovery pipe network.During preparation, the pulp preparation and pre-curing module mixes calcium-magnesium-containing solid waste and other raw materials and forms a base material with early strength in a closed pre-curing chamber; the gas injection and mineralization module injects carbon dioxide into the base material in a pressure-bearing space for mineralization curing; meanwhile, the dehumidification and gas circulation loop extracts high-humidity gas to separate water vapor and injects dry carbon dioxide, and the waste heat recovery pipe network collects carbonation reaction heat and conducts the heat to the pre-curing chamber.Through dynamic gas injection control and dehumidification circulation, the application ensures the uniformity of carbon dioxide penetration into the base material pores, prevents local reaction overheating from damaging the internal structure, meets the early hydration heat demand through heat energy closed loop, shortens the curing period and improves the mechanical strength of the product.

Description

Technical Field

[0001] This invention relates to the field of carbon dioxide mineralization building materials manufacturing technology, specifically to a CO2-pressurized carbon-fixed lightweight wall panel system and its preparation method. Background Technology

[0002] With the trend of low-carbon transformation in the construction industry, the demand for lightweight wall panels used in prefabricated buildings continues to increase. Traditional lightweight wall panel production often relies on high-temperature, high-pressure steam curing processes, which are energy-intensive and accompanied by significant indirect carbon emissions. To reduce carbon emissions, a technology that utilizes the mineralization reaction of carbon dioxide with building material raw materials to generate stable carbonates is gradually being introduced into wall panel manufacturing. However, existing carbon dioxide curing technologies are mostly concentrated in ordinary cement systems, and the co-utilization of large quantities of calcium- and magnesium-containing industrial solid wastes such as steel slag and blast furnace slag is insufficient, making it difficult to fully leverage the high calcium content advantage of these solid waste resources.

[0003] Current carbon dioxide curing processes typically treat building materials under normal or low pressure. Due to the high porosity of lightweight wall panels, low pressure makes it difficult for carbon dioxide to penetrate deeply into the material, resulting in a low overall carbon fixation rate and a lack of significant improvement in the mechanical strength of the finished product. Furthermore, existing curing systems lack environmental control measures tailored to the characteristics of porous materials. During the carbonization reaction, the substrate releases a large amount of heat, causing significant evaporation of internal free water. This accumulated water vapor easily condenses on the surface of the substrate's micropores, forming a liquid water film that physically blocks the continuous diffusion of carbon dioxide gas, further exacerbating the conflict between carbon fixation efficiency and strength development.

[0004] Furthermore, due to a lack of comprehensive system planning, existing equipment cannot effectively handle the heat of chemical reactions released during the carbonization stage. Excessive accumulation of this heat in localized areas can easily cause rapid vaporization of moisture within the substrate, damaging its structural strength. Directly discharging it as waste heat results in energy waste and fails to provide the necessary pre-curing thermal environment for the upstream powder slurry hydration. Therefore, existing technologies cannot effectively integrate the treatment of calcium- and magnesium-containing solid waste, internal energy loops, and forced diffusion of high-purity carbon dioxide, making it difficult to meet the industrial-scale production demands of high-performance, low-carbon, lightweight wall panels. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a CO2-pressurized carbon-fixed lightweight wall panel system and its preparation method. The aim is to solve the problem that the heat released by the carbonization reaction in existing technologies is not effectively recovered and utilized, resulting in energy waste in the system and failing to meet the thermal energy requirements for early hydration and pre-curing of the slurry.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: a CO2-pressurized carbon-fixed lightweight wall panel system and its preparation method, comprising:

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a carbon-fixing lightweight wall panel system and its preparation method, which improves the carbon fixation efficiency and mechanical properties of calcium- and magnesium-containing solid waste through heat transfer and gas circulation between modules.

[0008] The first aspect of this invention provides a CO2-pressurized carbon-fixed lightweight wall panel system, comprising:

[0009] The pulping and pre-curing module is used to receive calcium and magnesium-containing solid waste and cementing materials, perform grinding, screening, metering and mixing operations of materials, and provide a pre-curing environment with preset temperature and humidity conditions for the slurry after casting in a set closed pre-curing chamber. The gas injection and mineralization module is used to receive the substrate after the pre-curing process, receive the gasified carbon dioxide gas, provide a pressure-bearing space within the set pressure and temperature range, and control the carbon dioxide gas injection mode. The dehumidification and gas circulation loop is connected in series with the gas injection and mineralization module through a gas pipeline. It is used to extract the mixed gas in the pressurized space, separate free water and water vapor, and return the dehydrated dry gaseous carbon dioxide to the gas injection and mineralization module. The waste heat recovery pipeline network connects the gas injection and mineralization module and the pulping and pre-curing module through fluid medium pipelines. It is used to collect the heat generated during the reaction stage and conduct the heat to the closed pre-curing chamber of the pulping and pre-curing module.

[0010] A high-pressure carbon dioxide reaction environment is created by the gas injection and mineralization modules, which promotes the carbonization reaction and crystallization of calcium and magnesium minerals inside the substrate. Since the carbonization reaction is an exothermic process accompanied by the evaporation of internal free moisture, the system uses a waste heat recovery network to collect the reaction heat and transfer it to the pre-curing chamber, thereby meeting the heat energy required for the early slurry hydration and realizing the recycling of heat energy. At the same time, the system uses a dehumidification and gas circulation loop to continuously extract high-humidity gas from the reaction space, maintain the concentration of dry gaseous carbon dioxide, prevent the formation of a liquid water film on the substrate surface that hinders gas diffusion into the micropores, and ensure the uniformity of carbonization depth.

[0011] In one specific embodiment, the pulping and pre-curing module is equipped with a mechanical grinding device, a vibrating device, a metering device, and a mixer. The material enters the mechanical grinding device for crushing, and the ground material enters the vibrating device for screening. The fine powder raw material passing through the screen is independently transported to the metering device. The metering device weighs the calcium- and magnesium-containing solid waste and cementitious materials. After weighing, the dry mixed powder is transferred to the mixer, and mixing water is added to the mixer at the same time to form a powder slurry with uniform component distribution.

[0012] Preferably, the waste heat recovery pipeline network includes a circulating medium pump and a fluid proportioning valve. Driven by the circulating medium pump, the liquid heat transfer medium circulates along the pipeline, flowing through the heat exchange structure outside the gas injection and mineralization modules, absorbing the chemical reaction heat released by the carbonization reaction of other batches of substrates simultaneously. After absorbing heat and heating up, the liquid heat transfer medium flows into the sealed pre-curing chamber, flowing through the internal channels of the heat dissipation terminals deployed inside the chamber. The heat is conducted through the metal pipe walls and dissipated into the sealed pre-curing chamber. After releasing heat and cooling down, the liquid heat transfer medium is pumped back to the gas injection and mineralization modules via the return pipeline by the circulating medium pump.

[0013] Furthermore, the enclosed pre-curing room is equipped with a temperature sensor, a humidity sensor, a micro-water atomizer, and an exhaust fan. When the temperature sensor detects that the indoor temperature deviates from the set temperature range, it outputs an adjustment signal to the fluid proportional valve to change the flow rate of the liquid heat transfer medium flowing into the internal channel of the heat dissipation terminal. When the humidity sensor detects that the indoor relative humidity is lower than the preset lower humidity limit, it starts the micro-water atomizer to humidify the space. When the relative humidity is higher than the preset upper humidity limit, it turns on the exhaust fan to discharge some of the humid gas.

[0014] In one specific embodiment, the gas injection and mineralization module includes a gasification device, a buffer and pressure stabilizing unit, a pressure reducing valve assembly, and a gas storage buffer tank. Liquid carbon dioxide enters the gasification device and undergoes a phase change operation, transforming into room temperature gaseous carbon dioxide. The room temperature gaseous carbon dioxide flows into the buffer and pressure stabilizing unit, passes through the internal flow channel of the pressure reducing valve assembly to reduce its pressure, and is then filled into the gas storage buffer tank for temporary volume storage. The room temperature gaseous carbon dioxide, after being pressure-stabilized by the buffer and pressure stabilizing unit, is continuously input into the gas supply branch network of the gas injection and mineralization module.

[0015] Preferably, the pressure-bearing space is a closed cavity set inside the horizontal high-pressure reactor, and a loading trolley is loaded inside the horizontal high-pressure reactor; pressure-resistant isolation strips or corrugated support blocks are placed between two adjacent layers or two rows of substrates on the loading trolley to separate the wide and narrow sides of the adjacent substrates and form a reserved gas flow channel; a distributed temperature sensor matrix is ​​deployed in the reserved gas flow channel between the substrate layers.

[0016] In one specific embodiment, the gas injection and mineralization module includes a control unit, an intake valve group, an intake main valve, and a pulse solenoid valve group. The control unit generates a discrete temperature digital matrix based on the detection signals output by the distributed temperature sensor matrix. When the temperature of all nodes in the discrete temperature digital matrix is ​​lower than a preset absolute overheating threshold, and the temperature difference between the highest and lowest temperature nodes is lower than a preset spatial temperature difference threshold, the control unit outputs a normally open signal to the intake valve group on the gas supply branch network to maintain the continuous gas injection mode as the injection mode. When the temperature of any node in the discrete temperature digital matrix reaches the preset absolute overheating threshold, or the temperature difference between the highest and lowest temperature nodes reaches the preset spatial temperature difference threshold, the control unit drives the intake main valve and the pulse solenoid valve group on the corresponding area's gas supply branch to switch to the pulse alternating gas injection mode as the injection mode. Through the dynamic switching of the injection mode, the system uses pulsed airflow to generate pressure changes, forming airflow disturbances within the stack body, reducing local heat inside the stack body, and preventing excessively rapid reaction that could lead to rapid vaporization of moisture inside the substrate and damage to the structure.

[0017] In some embodiments, the metal pressure-bearing shell of the horizontal high-pressure reactor is covered with a heat exchange structure; an exhaust recovery valve is provided at the top of the chamber wall of the horizontal high-pressure reactor, and the residual carbon dioxide under high pressure flows into the externally installed gas recovery and purification unit through the recovery pipeline. The purified carbon dioxide is repressurized by the gas compressor and sent back to the gas storage buffer tank for storage.

[0018] In one specific embodiment, the dehumidification and gas circulation loop includes a circulating compressor, a dehumidification device, and a drain valve. The mixed gas is a high-humidity mixed gas containing water vapor and carbon dioxide. The high-humidity mixed gas is directionally extracted by the circulating compressor and flows into the dehumidification device. The high-humidity mixed gas flows over the surface of the cooling coil, where water vapor condenses into liquid water droplets and separates from the airflow. The separated liquid water droplets are discharged to the external network through the drain valve. The high-humidity mixed gas that has completed moisture removal is converted into dry gaseous carbon dioxide and re-injected into the pressurized space under the thrust of the circulating compressor.

[0019] A second aspect of the present invention provides a method for preparing a CO2-cured carbon-fixed lightweight wall panel, applicable to the aforementioned CO2-cured carbon-fixed lightweight wall panel system, comprising the following steps: The pulping and pre-curing module receives calcium- and magnesium-containing solid waste and cementitious materials, performs grinding, screening, metering and mixing operations to form slurry, and provides a pre-curing environment with preset temperature and humidity conditions for the slurry after casting in a closed pre-curing chamber, and outputs the substrate that has completed the pre-curing process. The gas injection and mineralization module receives the substrate that has completed the pre-curing process, receives the gasified carbon dioxide gas, provides a pressure-bearing space within a set pressure and temperature range, and controls the injection mode of the gasified carbon dioxide gas for mineralization curing. During the maintenance period, the mixed gas in the pressurized space is extracted using the dehumidification and gas circulation loop, free water and water vapor are separated, and the dehydrated dry gaseous carbon dioxide is returned to the gas injection and mineralization module. Simultaneously, the waste heat recovery pipeline network is used to collect the heat generated during the reaction stage and conduct the heat to the closed pre-curing chamber. After curing is completed, the lightweight wall panel product is output.

[0020] The hydration treatment of the powder slurry is followed by a subsequent pressurized carbonization process. Distributed temperature monitoring, combined with dehumidification and alternating air injection, controls the carbonization reaction rate of the substrate. Simultaneously, a fluid medium is used to achieve internal heat balance, thereby completing the consolidation of the lightweight wall panel and carbon dioxide sequestration. This invention provides a CO2-cured carbon-fixed lightweight wall panel system and its preparation method. It has the following beneficial effects: 1. The pulping and pre-curing module of this invention grinds, sieves, and measures calcium- and magnesium-containing solid waste and then thoroughly mixes them in a mixer, ensuring the uniformity of the slurry component distribution. Simultaneously, the system utilizes a waste heat recovery network to transfer the reaction heat generated by the gas injection and mineralization modules to the enclosed pre-curing chamber, maintaining the required temperature range for the pre-curing environment. This promotes the rapid formation of early strength in the cast substrate, meeting the requirements for subsequent demolding and stacking of products. This achieves the recycling of thermal energy and provides a reliable physical basis for the subsequent carbonization process.

[0021] 2. This invention achieves dynamic adjustment of the carbon dioxide injection mode through the gas injection and mineralization modules. The control unit, based on internal temperature field data fed back by a distributed temperature sensor matrix, automatically switches between continuous gas injection and pulsed alternating gas injection modes. It can make targeted adjustments according to changes in different reaction stages within the mineralization curing vessel, using pulsed airflow disturbance to reduce the temperature of locally overheated areas, preventing damage to the internal structure of the substrate due to excessively rapid reactions. This shortens the overall curing time while ensuring the final mechanical properties of the product.

[0022] 3. In a horizontal high-pressure reactor, this invention creates a reserved gas flow channel by placing isolation strips or support blocks between adjacent substrates. Combined with dehumidification and gas circulation loops, water vapor is continuously discharged and dry carbon dioxide is reinjected, providing a sufficient gas-solid contact interface for the fluid. By using stable high-purity carbon dioxide gas to replace the traditional autoclaving process, the physical resistance to gas diffusion into the deep micropores of the substrate is reduced, improving the penetration efficiency of the carbon fixation reaction and the product quality of the lightweight wall panel. Attached Figure Description

[0023] Figure 1 This is a system architecture diagram of the present invention; Figure 2 This is a schematic flowchart of the preparation method of the present invention; Figure 3 This is a dynamic evolution curve of the carbon fixation reaction in a specific application embodiment of the present invention. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on 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. It should be noted that, in this document, the substrate refers to the wall panel blank formed after the slurry is cast, pre-cured, and demolded, and is used for subsequent carbon dioxide pressure mineralization curing; the lightweight wall panel finished product refers to the final product obtained after the substrate has undergone carbon dioxide pressure mineralization curing. Unless otherwise stated, all descriptions related to the above objects in this document should be understood in this sense. See attached document Figure 1 and attached Figure 2 The present invention provides a carbon-fixed lightweight wall panel system for CO2 pressurized curing. The system may include: a pulping and pre-curing module, an air injection and mineralization module, a dehumidification and gas circulation loop, and a waste heat recovery pipeline network.

[0025] The pulping and pre-curing module is used to receive calcium- and magnesium-containing solid waste and cementing materials, perform grinding, screening, metering and mixing operations of materials, and provide a pre-curing environment under preset temperature and humidity conditions for the slurry after casting.

[0026] The gas injection and mineralization module is used to receive the substrate after the pre-curing process, receive the gasified carbon dioxide gas, provide a pressure-bearing space within the set pressure and temperature range, and control the carbon dioxide gas injection mode.

[0027] The dehumidification and gas circulation loop is connected in series with the gas injection and mineralization module via a gas pipeline. It is used to extract the mixed gas in the pressurized space, separate free water and water vapor, and return the dehydrated carbon dioxide gas to the gas injection and mineralization module.

[0028] The waste heat recovery pipeline network connects the gas injection and mineralization module and the pulping and pre-curing module through fluid medium pipelines. It is used to collect the heat generated during the reaction stage and conduct the heat to the pre-curing chamber of the pulping and pre-curing module.

[0029] Based on the above system architecture, this invention provides a method for preparing carbon-fixed lightweight wall panels under CO2 pressure curing, comprising the following steps: Step S1: The pulping and pre-curing module receives calcium- and magnesium-containing solid waste and cementitious materials. The raw materials are crushed by mechanical grinding equipment and screened by vibration equipment. The fine powder raw materials are weighed by metering equipment and transferred to the mixer, where they are mixed with mixing water to form a powder slurry with uniform component distribution.

[0030] Step S2: The mixed powder slurry is poured into the wall panel mold and transferred to the closed pre-curing chamber of the slurry preparation and pre-curing module; the waste heat recovery pipeline is turned on to absorb the chemical reaction heat released by the carbonization reaction of another batch of substrates at the same time, and the heat is dissipated through the heat dissipation terminal in the pre-curing chamber to maintain the preset temperature and humidity environment; after the powder slurry has been allowed to stand and hydrate for a set time, the demolding operation is performed to form the substrate for subsequent carbon dioxide pressure mineralization curing.

[0031] Step S3: The gas injection and mineralization module receives liquid carbon dioxide, which is then converted into room temperature gaseous carbon dioxide through phase change and depressurization treatment. The demolded lightweight wall panel is then transferred to the outside of the pressure-bearing space of the gas injection and mineralization module to construct a porous multi-layer stack. After deploying a distributed temperature sensor matrix between the substrate layers, the loading trolley is pushed into the pressure-bearing space to establish a signal interaction link and a sealed reaction boundary.

[0032] Step S4: Inject room temperature gaseous carbon dioxide into the pressurized space to purge residual air, establish the target curing pressure, and initiate dynamic pressure holding logic. During curing, the dehumidification and gas circulation loop performs closed-loop operations based on humidity monitoring data, including extracting high-humidity mixed gas, condensing and separating moisture, and reinjecting dehydrated mixed gas. Simultaneously, the system switches between continuous gas injection mode and pulsed alternating gas injection mode based on the thermodynamic state fed back by the distributed temperature sensor matrix. The waste heat recovery pipeline simultaneously exports the overall heat energy released by the carbonization reaction across sections to the pre-curing chamber. After the accumulated pressure holding curing time reaches the target time threshold, residual gas recovery and depressurization operations are performed, the sealed reaction boundary is released, and the multi-layer stack is removed, outputting the finished lightweight wall panel. For step S1, the pulping and pre-curing module performs mechanical processing of the basic materials and pulp preparation procedures, specifically including the following sub-steps: Step S11: The pulping and pre-curing module receives calcium-magnesium-containing solid waste and cementing materials. Various powdered or granular raw materials are separately conveyed and stored in a sealed storage silo configured within the pulping and pre-curing module for moisture protection. In this embodiment, the calcium-magnesium-containing solid waste includes fly ash, steel slag powder, or carbide slag, and the cementing materials include cement or other powdered materials with early hydration activity. The conveying device of the pulping and pre-curing module is activated to transfer the solid waste raw materials from the sealed storage silo to the receiving hopper. The material enters a mechanical grinding equipment for crushing via the receiving hopper. Preferably, a ball mill or vertical roller mill is used for the mechanical grinding equipment. The ground material enters a vibrating device for screening via a conveying channel. The vibrating device uses a high-frequency vibrating screen. The screen intercepts coarse particles that do not reach the set particle size and returns them to the mechanical grinding equipment for secondary crushing via a return pipeline. The fine powder raw material passing through the screen falls into the lower transition hopper for storage.

[0033] Step S12: According to the set formula ratio, the screw conveyor at the bottom of the transition hopper is activated. Various fine powder raw materials are independently conveyed to the metering equipment. The metering equipment uses an electronic powder scale equipped with a gravity sensor to weigh the solid waste raw materials and cementitious materials. After weighing, the dry-mixed powder is transferred to the mixer. In this embodiment, the mixer is a forced twin-shaft mixer, and the system simultaneously adds mixing water to the mixer through a liquid flow meter. The blades inside the mixer apply mechanical shear force, mixing the solid powder with the water phase to form a uniformly distributed powder slurry.

[0034] After completing the powder slurry preparation in step S12, the system executes step S2, which is performed collaboratively by the slurry preparation and pre-curing module and the waste heat recovery pipeline network, including the following sub-steps: In step S21, the pulping and pre-curing module controls the opening of the discharge gate at the bottom of the forced twin-shaft mixer, allowing the powder slurry to fall into the wall panel mold located below via a guide channel. During the injection process, a vibrating table located at the bottom of the mold is simultaneously activated, using high-frequency mechanical vibration to promote uniform spreading of the powder slurry within the mold cavity and dissipate any air trapped inside the slurry. After the injection and compaction operations are completed, the wall panel mold containing the base material slurry is placed on a track trolley and transferred along a pre-set guide rail to the pre-curing chamber of the pulping and pre-curing module. Preferably, the pre-curing chamber employs a closed chamber structure with thermal insulation material.

[0035] After the wall panel mold is placed in the pre-curing chamber, the system initiates cross-section heat allocation. The circulating medium pump configured on the waste heat recovery pipeline is activated, and the liquid heat transfer medium, which is sealed inside the pipeline, circulates along the pipeline under the pump's drive. The liquid heat transfer medium flows through the heat exchange structure outside the gas injection and mineralization modules, absorbing the heat of chemical reaction released by another batch of substrates undergoing simultaneous carbon dioxide mineralization curing.

[0036] In step S22, the liquid heat transfer medium, heated by absorbing heat energy, flows into the pre-curing chamber of the pulping and pre-curing module via a pipeline covered with external insulation material. A heat dissipation terminal is pre-installed in the pre-curing chamber; in this embodiment, the heat dissipation terminal is a finned tube radiator arranged along the inner wall of the chamber or a metal heat radiation plate laid at the bottom of the chamber. The high-temperature heat transfer medium flows through the internal channels of the heat dissipation terminal, and heat penetrates the metal pipe wall and dissipates into the pre-curing chamber space. The cooled liquid heat transfer medium, after releasing heat, is pumped back to the gas injection and mineralization module via a return pipeline. The system maintains the temperature and humidity environment in the pre-curing chamber based on feedback data. When the temperature sensor detects that the indoor temperature deviates from the set temperature range (preferably set to 15 to 35°C), the system outputs an adjustment signal to the fluid proportional valve on the waste heat recovery pipeline network, changing the flow rate of the high-temperature liquid heat transfer medium flowing into the heat dissipation terminal.

[0037] Step S23: When the humidity sensor detects that the indoor relative humidity is below the lower limit (preferably 20%), the system activates the micro-water atomizer located on the top of the chamber to humidify the space; when the relative humidity is above the upper limit (preferably 70%), the exhaust fan on the side wall of the chamber is turned on to expel some of the humid gas. The powder slurry loaded in the wall panel mold is continuously left to stand under the above temperature and humidity conditions. The cementitious material in the slurry absorbs water and undergoes an early hydration reaction, forming a gel network structure inside. After a set time of standing hydration, the operator or automated robotic arm releases the outer fasteners of the wall panel mold, separating the side plates and bottom plate of the mold. After demolding, a substrate for subsequent carbon dioxide pressure mineralization curing is obtained.

[0038] After the substrate is demolded and forms a lightweight wall panel, the system executes step S3, which includes the following sub-steps: Step S31: Activate the front-end gas source connection equipment configured for the gas injection and mineralization module. Liquid carbon dioxide transported by the tanker truck is connected to the receiving port of the front-end gas source connection equipment via a pressure-resistant hose. The liquid carbon dioxide flowing into the pipeline enters the vaporization device to perform a phase change operation. In this embodiment, the vaporization device adopts a combination structure of an ambient air vaporizer and a water bath electric heater. The liquid carbon dioxide flows through the finned tube array surrounding the ambient air vaporizer and undergoes preliminary vaporization, transforming into low-temperature gaseous carbon dioxide. The low-temperature gas, after the preliminary phase change, flows into the water bath electric heater, undergoes a secondary heating, and transforms into ambient temperature gaseous carbon dioxide with a temperature higher than the target ambient temperature (e.g., 5°C).

[0039] At room temperature, gaseous carbon dioxide flows into the buffer and pressure-stabilizing unit, passing through the internal flow channels of the pressure-reducing valve assembly. The pressure is gradually reduced from the initial high pressure of liquefaction storage to a set delivery pressure range (preferably configured as 1.2 to 1.5 MPa). The depressurized carbon dioxide gas is then temporarily stored in a gas storage buffer tank, where the increased storage space smooths out transient pressure fluctuations generated during vaporization. The high-purity carbon dioxide gas, after pressure stabilization, is continuously supplied along the main gas supply pipeline to the gas supply branch network of the gas injection and mineralization module. Simultaneously, the system performs substrate loading operations when the front-end gas source completes the preparation and storage phase. The reaction process between carbon dioxide and the solid substrate depends on the penetration depth of the gaseous reactants into the micropores. If adjacent wall panel substrate surfaces are tightly bonded, the gas permeation channels at the contact interface will block each other, hindering the diffusion of carbon dioxide gas inward. Therefore, a gas flow network needs to be pre-constructed during the substrate stacking stage.

[0040] In step S32, the automated hoisting equipment transfers the demolded substrate to the outside of the pressure-bearing space of the gas injection and mineralization module for loading. In this embodiment, the pressure-bearing space is a closed cavity configured inside a horizontal high-pressure reactor. The handling equipment lays the substrate flat or places it upright on the loading trolley. Pressure-resistant isolation strips or corrugated support blocks are pre-placed between adjacent layers or rows of substrates to forcibly separate the wide and narrow sides of adjacent lightweight wall panels. The structural thickness of the aforementioned pressure-resistant isolation strips determines the interlayer gap size. Based on the on-site gas source pressure parameters, the width of the gas flow channel reserved between adjacent lightweight wall panels is set as the target spacing parameter (as a preferred method, the specific value is set to 25 mm). Through the regular insertion of isolation components, a porous multi-layered stack with longitudinal and transverse grid gas channels is formed on the loading trolley.

[0041] Step S33: While constructing the multi-layered stack, the deployment of the internal signal sensing network is completed simultaneously. The carbonization reaction of calcium-magnesium minerals is an exothermic process. Due to differences in gas permeation resistance and heat conduction paths within the multi-layered stack, a spatially uneven temperature field is generated. The operating equipment deploys a distributed temperature sensor matrix within the gas flow channels reserved between the substrate layers. In this embodiment, the sensors are K-type thermocouples or high-pressure resistant fiber optic grating temperature sensors. According to the established three-dimensional spatial coordinate system, the sensors are arranged in a grid pattern along the length, width, and height directions of the stack. The nodes are arranged to forcibly cover the front windward area, the core hinterland area, and the rear leeward area of ​​the stack. The division of these three areas is based on the following: along the main flow direction from the reactor inlet to the outlet, the interval representing 0% to 20% of the distance from the inlet is designated as the front windward area; the interval representing 20% ​​to 80% is designated as the core hinterland area; and the interval representing 80% to 100% is designated as the rear leeward area. Based on the coordinate division rules mentioned above, a discrete temperature acquisition point array is formed inside the stack.

[0042] Step S34: After completing the above operations, the loading trolley, fully loaded with substrate and equipped with the sensor matrix, is pushed along the track into the depths of the horizontal high-pressure reactor. The distributed temperature sensor matrix deployed between the stacked layers needs to establish a signal interaction link with the control unit outside the reactor body to output the detection signal. The signal transmission cables extending from the sensor tails are collected in the junction box on the side of the loading trolley. The junction box is connected to the pre-set high-pressure resistant sealed lead assembly on the wall of the gas injection and mineralization module via a flexible heat-resistant wire harness. In this embodiment, the high-pressure resistant sealed lead assembly uses a glass sintered sealing joint or an epoxy resin injection flange. The above components allow the electrical signal wires to penetrate the pressure-bearing metal wall while withstanding the internal megapascal-level high pressure without gas leakage.

[0043] The initial analog signal penetrating the bulkhead is directed to the control unit located under normal pressure. The analog input module within the control unit performs signal filtering and analog-to-digital conversion, generating a discrete temperature digital matrix with three-dimensional coordinate labels. This temperature digital matrix maps the real-time thermodynamic state at different locations within the stack and serves as a core input variable for the control unit to determine local overheating and trigger valve pulses during subsequent pressure curing. After completing a signal link connectivity self-check and confirming stable data transmission, the control unit outputs a command to drive the hydraulic locking mechanism of the end vessel door to close, and injects fluid into the flange sealing groove to cause the sealing ring to expand, establishing a sealed reaction boundary that blocks external atmospheric communication.

[0044] After the preparation work is completed and the closed reaction boundary is established, the system executes step S4, which includes the following sub-steps: In step S41, the pressurized space, initially filled with ambient air, retains residual air that dilutes the carbon dioxide concentration, slowing down the carbon fixation reaction rate. The system opens the main intake valve and vent valve configured in the gas injection and mineralization modules. Room-temperature gaseous carbon dioxide supplied by the buffer and pressure stabilizing unit enters the pressurized space, displacing the remaining mixed gas through the vent valve. A carbon dioxide concentration sensor is installed at the end of the vent pipeline. When the carbon dioxide concentration in the discharged gas reaches a set purity threshold (e.g., 95%), the system outputs an electrical signal to close the vent valve. After the vent valve closes, the main intake valve remains open, allowing carbon dioxide gas to continuously flow into the sealed pressurized space, causing the internal pressure to rise. A pressure transmitter installed on the side wall of the pressurized space collects real-time internal environmental pressure data. When the pressure transmitter feedback value reaches the set target maintenance pressure upper limit (e.g., 0.4 MPa), the system triggers the main intake valve to close, interrupting the gas injection process.

[0045] After the sealed system is established, the calcium and magnesium minerals inside the substrate undergo a carbonization reaction with the permeated carbon dioxide. The carbonization reaction consumes gaseous reactants and is accompanied by heat, causing the air pressure in the pressure-bearing space to drop and the temperature to rise. The system then activates the dynamic pressure-maintaining logic. When the pressure transmitter feedback value drops to the lower limit of the target curing pressure (e.g., 0.35 MPa), the system drives the main air intake valve to reopen and replenish air until the air pressure rises back to the upper limit of the target curing pressure.

[0046] In step S42, during the pressure holding logic, the carbonization reaction releases heat and generates free water. As the reaction is exothermic, moisture inside the substrate evaporates outwards, causing the humidity in the pressure-bearing space to rise. Excessive humidity forms a liquid water film on the substrate surface, hindering the diffusion of carbon dioxide gas into the internal pores. The system continuously acquires humidity monitoring data within the pressure-bearing space. When the relative humidity exceeds a set warning threshold (e.g., 85%), the circulating compressor in the dehumidification and gas circulation loop is activated. The high-humidity mixture of water vapor and carbon dioxide inside the pressure-bearing space is directionally extracted by the fan, and the extracted high-humidity mixture flows into the dehumidification device along the pressure-resistant sealed pipeline.

[0047] In this embodiment, the dehumidification device employs a condensing gas-liquid separator with a built-in cooling coil. High-humidity mixed gas flows over the surface of the cooling coil, causing the gas temperature to drop below the dew point temperature. Water vapor condenses into liquid water droplets and separates from the airflow, eventually collecting in a bottom water collection tank. The separated liquid water is periodically discharged to an external network via a drain valve. The dehydrated mixed gas, having undergone moisture removal, is reconstituted into dry gaseous carbon dioxide and reinjected into the pressurized space under the thrust of a circulating compressed air fan. The extraction, condensation separation, and reinjection actions form a closed-loop fluid network within the hardware piping, maintaining unobstructed continuous permeation channels for carbon dioxide gas into the solid substrate.

[0048] Step S43: During the dehumidification cycle synchronization phase, the system continuously assesses the internal thermodynamic state of the stack. If a local area reacts too quickly, the rapidly accumulated heat will cause the moisture inside the substrate to vaporize rapidly. The system extracts a discrete temperature digital matrix from the analog input module, obtains the real-time temperature values ​​of all acquisition points in three-dimensional space, and compares them with the set safety threshold conditions.

[0049] The safety threshold conditions include an absolute overheat threshold (e.g., 80 degrees Celsius) and a spatial temperature difference threshold (e.g., 20 degrees Celsius). When the temperature of all nodes in the discrete temperature digital matrix is ​​below the absolute overheat threshold, and the temperature difference between the highest and lowest temperature nodes is below the spatial temperature difference threshold, it indicates that the carbonization reaction inside the stack is stable and the heat distribution is uniform. At this time, the control unit outputs a normally open signal to the intake valve group on the gas supply branch network to maintain the continuous gas injection mode and ensure the supply of basic reaction gas.

[0050] When any node in the discrete temperature digital matrix reaches the absolute overheating threshold, or when the temperature difference between the highest and lowest temperature nodes reaches the spatial temperature difference threshold, it indicates localized heat accumulation inside the stack. The system then activates the main intake valve and the pulse solenoid valve group on the corresponding area's air supply branch pipe, switching to pulse alternating gas injection mode. The system periodically closes and opens the pulse solenoid valve group according to a set pulse frequency (e.g., 1 Hz). The periodic valve operation causes transient pressure pulsations in the airflow into the pressurized space, creating forced convection disturbances within the reserved gas flow channels of the stack, stripping away the trapped gas layer on the substrate surface, accelerating the mixing of high-temperature gas inside the stack with low-temperature fluid outside, and slowing down the local reaction rate. Once the temperature values ​​returned from subsequent monitoring cycles fall back to within the safe threshold conditions, the system stops the pulse alternating gas injection mode and resumes normal continuous gas injection operation.

[0051] In step S44, while the pulse gas injection mode is being implemented, the overall heat energy continuously released by the carbonization reaction within the pressurized space will diffuse to the external environment. The system performs a cross-section heat removal process through the external pipeline network. The heat released by the carbonization reaction penetrates the metal pressure-bearing shell of the horizontal high-pressure reactor and is transferred to the heat exchange structure surrounding the cabin wall.

[0052] In this embodiment, the heat exchange structure employs a semi-tubular jacket welded to the outer surface of the shell. A circulating medium pump configured on the waste heat recovery pipeline drives a low-temperature liquid heat transfer medium into the internal flow channel of the semi-tubular jacket, where it undergoes convective heat exchange with the heated metal pressure-bearing shell. After absorbing heat energy, the liquid heat transfer medium transforms into a high-temperature liquid heat transfer medium and flows out of the heat exchange structure, merging into the delivery pipeline of the waste heat recovery pipeline. The heat transfer medium carrying the reaction heat energy is directionally pumped to the pre-curing chamber of the pulping and pre-curing module to release heat. The actions of the gas injection and mineralization module in removing excess waste heat and the heat replenishment requirements of the pulping and pre-curing module achieve a two-way match, constructing a closed-loop energy flow channel across modules.

[0053] In step S45, as the cross-section heat removal and dehumidification cycle operation continues, the reactive mineral phase inside the substrate is gradually consumed. When the accumulated pressure holding and curing time of the system's preset timing module reaches the set target time threshold (e.g., 8 hours), a termination command is output to the associated equipment. The system closes the main inlet valve on the gas supply branch network, blocking the input path of ambient temperature gaseous carbon dioxide. Unreacted high-pressure carbon dioxide gas still resides in the pressure-bearing space of the horizontal high-pressure reactor. The system opens the exhaust recovery valve located at the top of the chamber wall, and the residual carbon dioxide under high pressure flows into the externally configured gas recovery and purification unit through the recovery pipeline.

[0054] In this embodiment, the gas recovery and purification unit includes a cyclone dust collector and a gas compressor connected in series. Residual gas passes through the cyclone dust collector to remove entrained fine dust particles. The purified gaseous carbon dioxide is repressurized by the gas compressor and transported back to a large-capacity gas storage buffer tank. The internal pressure of the pressurized space gradually decreases. The system continuously reads the real-time monitoring values ​​from the pressure transmitter. When the returned pressure value drops to equal the external atmospheric pressure reference value, a control signal is output to drive the hydraulic locking mechanism of the end vessel door to perform an unlocking and reverse action, simultaneously extracting the filling fluid from the flange sealing groove. The expanded sealing ring retracts, releasing the established sealed reaction boundary. An external power unit pulls the end vessel door open, and an automated traction trolley connects to the loading trolley chassis via a mechanical hook, removing the multi-layer stack containing the lightweight wall panel products. On-site operating equipment removes the pre-set pressure-resistant isolation strips between the substrates and recovers the distributed temperature sensor matrix deployed between the layers. After curing, the internal pores of the powder substrate are filled and solidified by the generated calcium carbonate crystal network, and the wall panel achieves the mechanical compressive strength required by building industry standards and specifications. The hoisting equipment then transfers the finished lightweight wall panels to the finished product stacking area, completing the manufacturing process for the current batch of lightweight wall panels.

[0055] Specific application examples: 30% steel slag powder, 20% fly ash, and 50% early-stage hydration active cement were selected as the solid phase mixture.

[0056] After being crushed by a vertical roller mill and screened by a high-frequency vibrating screen, the fine powder has a specific surface area of ​​420 m². 2 / kg. After weighing, add to a forced twin-shaft mixer, add mixing water at a water-to-binder ratio of 0.4, and stir for 3 minutes to form a powder slurry.

[0057] The powder slurry is poured into a lightweight wall panel mold (size: 2400mm×600mm×100mm), compacted using a bottom vibrating table, and then sent into a pre-curing chamber.

[0058] Waste heat from the reactor is introduced through a waste heat recovery network, and the temperature in the pre-curing chamber is maintained at 25°C with a relative humidity of 60%. After standing for 12 hours, the substrate develops initial setting strength, and demolding is then performed.

[0059] Liquid CO 2 The gas is heated to 15°C by a combined air-temperature and water-bath vaporizer, and then pressurized to 1.5 MPa before being filled into the buffer tank.

[0060] After demolding, the wall panels are placed on a loading trolley, with 25 mm thick pressure-resistant isolation strips pre-installed between layers. Twenty-seven K-type thermocouples (forming a 3×3×3 three-dimensional temperature sensor matrix) are deployed within the stack, which is then pushed into the horizontal high-pressure reactor, and the reactor door is locked.

[0061] After purging the air, CO is injected into the reactor.2 Establish a target maintenance pressure of 0.4 MPa.

[0062] During the second hour of maintenance, the humidity transmitter showed that the relative humidity reached 88% (exceeding the 85% warning line). The system automatically started the circulating compressor fan to extract the high-humidity gas, condense and dehydrate it, and then reinject it back, bringing the humidity back to about 75%.

[0063] During the third hour of maintenance, the sensor matrix reported that the temperature at a certain node reached 82℃ (exceeding the absolute overheating threshold of 80℃), and the maximum temperature difference reached 24℃. The system immediately switched to a 1Hz pulse alternating gas injection mode. After 15 minutes, strong convection caused the internal temperature to drop back to 72℃, the temperature difference decreased to 12℃, and the continuous gas injection mode was resumed.

[0064] After a cumulative pressure holding and curing period of 8 hours, residual CO was recovered. 2 After depressurization and opening of the reactor, finished carbon-fixed lightweight wall panels are produced.

[0065] Experimental verification and effect comparison: To verify the effectiveness of this invention, three control groups were established for plate-making experiments (all formulas and dimensions were the same): Comparative Example A: Cured using traditional high-temperature and high-pressure steam (180℃, 1.2MPa, CO2-free). 2 Intervention and maintenance for 8 hours).

[0066] Comparative Example B: Only CO was injected into the high-pressure reactor. 2 (0.4MPa, constant continuous gas injection, no dehumidification circulation, no pulse control, no waste heat recovery, 8 hours of curing).

[0067] Example C: The complete steps of the above specific embodiment (0.4MPa, including dehumidification circulation, pulse control and waste heat recovery, curing for 8 hours).

[0068] The experimental results are shown in the table below:

[0069] Experimental conclusion: Referring to the above experimental test data and appendix Figure 3 Comparative Example B, represented by the dashed line, showed an increase in carbon fixation rate over time in the initial curing stage. However, after approximately 2 hours of reaction, the free water generated by the carbonization reaction was not discharged and formed a liquid film on the surface of the internal pores, hindering the diffusion of carbon dioxide to the core area of ​​the substrate. Consequently, the carbon fixation rate curve became passivated and plateaued, eventually reaching a reaction stagnation rate of only 8.4%. Example C, represented by the solid line, effectively eliminated the physical barrier of the liquid film by continuously performing moisture stripping and dry gas reinjection operations through a dehumidification device. Figure 3The carbon fixation rate curve corresponding to Example C continued its steady upward trend after passing the 2-hour mark. The unobstructed gas-phase permeation channels enabled the deep mineralization of carbon dioxide to continue, ultimately increasing the carbon fixation rate to 19.6%. The large number of dense calcium carbonate crystal networks generated internally enabled the wall panel to achieve a final compressive strength of 15.8 MPa, which meets or even slightly exceeds the traditional autoclaving benchmark.

[0070] The carbonization of calcium and magnesium minerals is a violently exothermic reaction. In Comparative Example B, due to the lack of real-time monitoring and intervention of the internal thermodynamic state, heat continuously accumulated in the core area of ​​the stack, with the actual temperature difference between the center and the edge reaching 35°C. This caused irreversible thermal stress microcracks to form inside the lightweight wall panel, and the structural compressive strength dropped to 10.5 MPa. Example C utilizes a distributed temperature sensor matrix to form a closed-loop feedback. When a local heat accumulation trend occurs, a 1 Hz pulse alternating gas injection mode is immediately switched on. Through the periodic transient changes in airflow pressure, forced convection disturbances are formed in the interlayer gaps, accelerating the dissipation of high-temperature gas inside the stack and controlling the global maximum temperature difference within a safe threshold (14°C), thus ensuring the overall structural integrity of the lightweight wall panel.

[0071] Comparative Example A requires the combustion of large amounts of fossil fuels to produce high-temperature, high-pressure steam, with energy consumption per unit of board material reaching as high as 145 kWh / m². 3 Example C utilizes a waste heat recovery network to directionally transfer the waste heat from the carbonization reaction accumulated on the outer shell of the high-pressure reactor to the pre-curing chamber via a liquid heat transfer medium, directly replacing the basic heating energy consumption of the pre-curing section. The heat dissipation requirements of the gas injection and mining sections are matched bidirectionally with the heat replenishment requirements of the pre-curing section, resulting in a significant reduction in overall unit energy consumption to 18 kWh / m². 3 While ensuring the carbon sequestration properties of the materials, carbon reduction in the production process was achieved.

Claims

1. A CO2-pressurized carbon-fixed lightweight wall panel system, characterized in that, include: The pulping and pre-curing module is used to receive calcium and magnesium-containing solid waste and cementing materials, perform grinding, screening, metering and mixing operations of materials, and provide a pre-curing environment with preset temperature and humidity conditions for the slurry after casting in a set closed pre-curing chamber. The gas injection and mineralization module is used to receive the substrate after the pre-curing process, receive the gasified carbon dioxide gas, provide a pressure-bearing space within a set pressure and temperature range, and control the injection mode of the carbon dioxide gas. The dehumidification and gas circulation loop is connected in series with the gas injection and mineralization module through a gas pipeline. It is used to extract the mixed gas in the pressurized space, separate free water and water vapor, and return the dehydrated dry gaseous carbon dioxide to the gas injection and mineralization module. The waste heat recovery pipeline network is connected to the gas injection and mineralization module and the pulping and pre-curing module through fluid medium pipelines. It is used to collect the heat generated during the reaction stage and conduct the heat to the closed pre-curing chamber of the pulping and pre-curing module.

2. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 1, characterized in that, The pulping and pre-curing module is equipped with mechanical grinding equipment, vibration equipment, metering equipment and a mixer; The material enters the mechanical grinding equipment for crushing, and the ground material enters the vibrating equipment for screening. The fine powder raw material passing through the screen is independently conveyed to the metering equipment. The metering device weighs the calcium- and magnesium-containing solid waste and cementitious materials. After weighing, the dry-mixed powder is transferred to the mixer, and mixing water is added to the mixer at the same time to form a powder slurry with uniform component distribution.

3. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 1, characterized in that, The waste heat recovery pipeline network includes a circulating medium pump and a fluid proportional valve; The liquid heat transfer medium circulates along the pipeline under the drive of the circulating medium pump, flows through the heat exchange structure outside the gas injection and mineralization module, and absorbs the chemical reaction heat released by the carbonization reaction of another batch of substrates at the same time. The liquid heat-conducting medium, after absorbing heat energy and heating up, flows into the closed pre-curing chamber and flows through the internal flow channel of the heat dissipation terminal deployed in the chamber. The heat is conducted through the metal pipe wall and dissipated into the closed pre-curing chamber. After releasing heat and cooling down, the liquid heat-conducting medium is pumped back to the gas injection and mineralization module by the circulating medium pump through the return pipeline.

4. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 3, characterized in that, The enclosed pre-curing chamber is equipped with a temperature sensor, a humidity sensor, a micro water atomizer, and an exhaust fan. When the temperature sensor detects that the indoor temperature deviates from the set temperature range, it outputs an adjustment signal to the fluid proportional valve to change the flow rate of the liquid heat-conducting medium flowing into the internal channel of the heat dissipation terminal. When the humidity sensor detects that the indoor relative humidity is lower than the preset lower humidity limit, the micro water atomizer is activated to humidify the space; when the relative humidity is higher than the preset upper humidity limit, the exhaust fan is turned on to discharge some of the humid gas.

5. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 1, characterized in that, The gas injection and mineralization module includes a gasification device, a buffer and pressure stabilizing unit, a pressure reducing valve group, and a gas storage buffer tank. Liquid carbon dioxide enters the gasification device and undergoes a phase change operation, transforming into gaseous carbon dioxide at room temperature. The ambient temperature gaseous carbon dioxide flows into the buffer and pressure stabilizing unit, passes through the internal flow channel of the pressure reducing valve group to reduce pressure, and is then filled into the gas storage buffer tank for temporary volume storage. The ambient temperature gaseous carbon dioxide, after being stabilized by the buffer and pressure stabilizing unit, is continuously input into the gas supply branch network of the gas injection and mineralization module.

6. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 5, characterized in that, The pressure-bearing space is a closed cavity set inside the horizontal high-pressure reactor, and a loading trolley is loaded inside the horizontal high-pressure reactor; The loading trolley places pressure-resistant isolation strips or corrugated support blocks between two adjacent layers or two columns of the substrate to separate the wide and narrow sides of the adjacent substrates, forming a reserved gas flow channel. A distributed temperature sensor matrix is ​​deployed within the reserved gas flow channels between the substrate layers.

7. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 6, characterized in that, The gas injection and mineralization module includes a control unit, an intake valve group, an intake main valve, and a pulse solenoid valve group. The control unit generates a discrete temperature digital matrix based on the detection signal output by the distributed temperature sensor matrix. When the temperature of all nodes in the discrete temperature digital matrix is ​​lower than the preset absolute overheating threshold, and the temperature difference between the highest and lowest temperature nodes is lower than the preset spatial temperature difference threshold, the control unit outputs a normally open signal to the intake valve group on the gas supply branch network to maintain the continuous gas injection mode as the injection mode. When any node temperature in the discrete temperature digital matrix reaches the preset absolute overheating threshold, or when the temperature difference between the highest and lowest temperature nodes reaches the preset spatial temperature difference threshold, the main intake valve and the pulse solenoid valve group on the corresponding area supply branch pipe are driven to switch to the pulse alternating injection mode as the injection mode.

8. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 6, characterized in that, The horizontal high-pressure reactor has a metal pressure-bearing shell covered with a heat exchange structure. The top of the horizontal high-pressure reactor chamber is equipped with an exhaust recovery valve. The residual carbon dioxide under high pressure flows into the external gas recovery and purification unit through the recovery pipeline. The purified carbon dioxide is repressurized by the gas compressor and sent back to the gas storage buffer tank for storage.

9. The CO2-pressurized lightweight carbon-fixing wall panel system according to claim 1, characterized in that, The dehumidification and gas circulation loop includes a circulating compressor, a dehumidification device and a steam trap, and the mixed gas is a high-humidity mixed gas containing water vapor and carbon dioxide. The high-humidity mixed gas is drawn out in a direction by the suction action of the circulating compressor and flows into the dehumidification device. The high-humidity mixed gas flows over the surface of the cooling coil, and the water vapor condenses into liquid water droplets and separates from the airflow. The separated liquid water droplets are discharged to the external network through the condensate valve. The high-humidity mixed gas, after moisture removal, is converted into dry gaseous carbon dioxide and then reinjected into the pressurized space under the thrust of the circulating compressor.

10. A method for preparing a CO2-cured carbon-fixed lightweight wall panel, applied to the CO2-cured carbon-fixed lightweight wall panel system according to any one of claims 1-9, characterized in that, Includes the following steps: The pulping and pre-curing module receives calcium- and magnesium-containing solid waste and cementitious materials, performs grinding, screening, metering and mixing operations to form a slurry, and provides a pre-curing environment with preset temperature and humidity conditions for the slurry after casting in a closed pre-curing chamber, and outputs a substrate that has completed the pre-curing process. The gas injection and mineralization module receives the substrate that has completed the pre-curing process, receives the gasified carbon dioxide gas, provides a pressure-bearing space within a set pressure and temperature range, and controls the injection mode of the gasified carbon dioxide gas to carry out mineralization curing. During the maintenance period, the mixed gas in the pressurized space is extracted using a dehumidification and gas circulation loop, free water and water vapor are separated, and the dehydrated dry gaseous carbon dioxide is returned to the gas injection and mineralization module. Simultaneously, the waste heat recovery pipeline network is used to collect the heat generated during the reaction stage and conduct the heat to the closed pre-curing chamber. After curing is completed, the lightweight wall panel product is output.

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