Efficient CO2 mineralization and storage device and method based on multi-mode micro-nano bubble generation and dynamic proportion regulation and control

Abstract

The invention relates to an efficient CO2 mineralization and storage device and method based on multi-mode micro-nano bubble generation and dynamic proportion regulation and control, and belongs to the technical field of concrete preparation. The device comprises a frame, a multi-mode micro-nano bubble refining device, a static mixer, a cement stirring device and a controller, the multi-mode micro-nano bubble refining device, the cement stirring device and the controller are arranged on the frame, and the multi-mode micro-nano bubble refining device is connected with the cement stirring device through the static mixer. The multi-mode micro-nano bubble refining device, the static mixer and the cement stirring device are all connected with a controller. According to the invention, the multi-mode micro-nano bubble generation device is adopted, and the defects of non-uniform bubble size, poor stability or high energy consumption generated by a single technology are overcome through the triple technology combination of the rotating impeller, the ultrasonic vibration device and the microporous membrane.

Description

Technical Field

[0001] The present invention relates to a high-efficiency mineralization and CO2 storage device and method based on multimodal micro-nano bubble generation and dynamic ratio control, belonging to the technical field of concrete preparation. Background Art

[0002] The building materials industry is facing great pressure to reduce carbon emissions, and the research on carbon sequestration concrete has received great attention and rapid development. Carbon capture, utilization and storage (CCUS) technology is an effective measure to reduce carbon dioxide emissions from cement. By accelerating carbonation solidification, cement clinker, mineral admixtures and hydration products react with carbon dioxide to produce thermodynamically stable carbonates, which can fix carbon dioxide in cement-based materials for long-term storage, thereby achieving net zero carbon emissions throughout the service life of cement-based materials. The existing wet carbonization process directly introduces CO2 gas into the cement slurry. Due to the limited solubility of the gas in the liquid phase and the insufficient gas-liquid contact area, the reaction rate is slow, and a large amount of CO2 escapes without participating in the reaction, resulting in a waste of resources. Unlike wet carbonization, which directly introduces CO2 gas into the slurry, micro-nano bubble technology is currently used. By efficiently breaking the CO2 gas into micro-nano bubbles of 100-500nm, the gas-liquid contact area (specific surface area > 100m 2 / m 3 ) and dissolution efficiency (increased by 3-5 times). Provide more sufficient CO2 supply and a more uniform dispersion system for subsequent mineralization reactions.

[0003] The current application of micro-nano bubble technology in the field of carbon dioxide mineralization and storage still has significant limitations. Traditional methods mainly rely on single bubble generation technology, which is difficult to simultaneously meet the requirements of bubble particle size uniformity, stability and generation efficiency. The micro-nano bubbles prepared by a single technology have poor dispersion in cement-based materials, and the CO2 dissolution efficiency is generally less than 50%, resulting in insufficient mineralization reaction and the storage rate is difficult to exceed 60%.

[0004] As a carbon-fixing carrier, fly ash is highly reactive and porous. Its abundant surface active sites and pore structure enable efficient CO2 adsorption, providing space for the uniform attachment of nano-calcium carbonate. However, the feed ratio of fly ash to CO2 and cement lacks a scientifically determined basis. The traditional fixed-ratio feed method cannot adapt to fluctuations in raw material composition (e.g., a ±5% variation in fly ash CaO content). This extensive ratio control severely restricts the maximization of fly ash's nucleation effect, resulting in low CO2 utilization (<60%), incomplete raw material reaction (30% not carbonized), and significant waste. The lack of a real-time feedback mechanism makes the reaction susceptible to temperature fluctuations (±2°C) and uneven bubble size distribution (100-1000nm). This ultimately leads to unstable product quality (strength fluctuations of ±15%) and increased costs (CO2 waste of $20-30 per ton of cement). Furthermore, the traditional process lacks real-time monitoring and dynamic adjustment of key parameters such as pH and temperature in the reaction system, making it difficult to maintain optimal reaction conditions.

[0005] Therefore, there is an urgent need to develop an efficient mineralization storage solution that integrates multimodal micro-nano bubble generation technology, precise proportion control and intelligent feedback system to solve the core problems of low bubble generation efficiency, poor reaction controllability and insufficient storage rate in existing technologies. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a high-efficiency mineralization and storage CO2 device and method based on multimodal micro-nano bubble generation and dynamic ratio control.

[0007] The technical solutions of the present invention are as follows:

[0008] A high-efficiency mineralization and CO2 storage device based on multimodal micro-nano bubble generation and dynamic proportion control includes a frame, a multimodal micro-nano bubble refinement device, a static mixer, a cement mixing device and a controller. The frame is provided with the multimodal micro-nano bubble refinement device, the cement mixing device and the controller, the multimodal micro-nano bubble refinement device is connected to the cement mixing device via the static mixer, and the multimodal micro-nano bubble refinement device, the static mixer and the cement mixing device are all connected to the controller.

[0009] Preferably, according to the present invention, the multimodal micro-nano bubble refinement device includes a carbon dioxide intake device, a micro-nano bubble generating device and a liquid delivery device, the carbon dioxide intake device and the liquid delivery device are respectively connected to the micro-nano bubble generating device, and the micro-nano bubble generating device is connected to a static mixer.

[0010] Preferably, according to the present invention, the micro-nano bubble generating device includes a shell, a motor A, a rotating impeller, an ultrasonic vibration device and a microporous membrane. A rotating impeller is provided at the bottom of the shell, the rotating impeller is externally connected to the motor A, an ultrasonic vibration device is provided in the middle of the shell, a microporous membrane is provided on the upper part of the shell, and a liquid conveying device and a static mixer are connected to the two sides of the top of the shell through the liquid inlet and the liquid outlet respectively, and the bottom of the shell is connected to the carbon dioxide intake device through the air inlet.

[0011] Preferably, according to the present invention, the rotating impeller speed is 1000-20000rpm, and the carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The impeller material is corrosion-resistant stainless steel or ceramic to adapt to the weakly acidic environment; the ultrasonic vibration device frequency is 20-40kHz, and the carbon dioxide gas is broken into micro-nano bubbles by the cavitation effect. The ultrasonic vibrator is preferably made of piezoelectric ceramic material with high energy conversion efficiency; the microporous membrane adopts a microporous membrane with a pore size of 0.1-10μm, and the carbon dioxide gas is dispersed into micro-nano bubbles by physical filtration. The membrane material is polytetrafluoroethylene (PTFE) with high chemical stability and low surface energy.

[0012] Preferably according to the present invention, a temperature sensor and a bubble particle size analyzer are provided on the connecting pipe between the shell and the static mixer.

[0013] According to the preferred embodiment of the present invention, the carbon dioxide intake device includes a gas tank for storing carbon dioxide, a gas flow controller and a gas filter. The gas tank is connected to a micro-nano bubble generating device through the gas flow controller and the gas filter. A pressure regulating valve is provided on the gas tank. The gas flow controller is EL-FLOW series gas flow controller, gas filter for Acro 50 series gas filter model AP020F50S.

[0014] Preferably, according to the present invention, the liquid conveying device includes a liquid storage tank, a cooling device and a high-pressure water pump connected in sequence. The water outlet of the high-pressure water pump is connected to the micro-nano bubble generating device through a liquid flow controller. The liquid storage tank has a capacity of 20L and stores deionized water as a carbon dioxide dissolving medium; the high-pressure water pump transports deionized water into the micro-nano bubble generating device; the liquid flow controller accurately adjusts the liquid flow to ensure that it matches the gas flow, and the cooling device controls the liquid temperature to optimize the solubility and reaction efficiency of carbon dioxide.

[0015] Preferably, according to the present invention, the static mixer includes a mixing tube, which is provided with a feeding port, and the feeding port extends into the mixing tube at 1 / 30, thereby improving the mixing effect without causing corrosion of the feeding port. A flow rate difference of 5:1 is formed between the feeding port and the feeding port of the mixing tube to enhance mixing. A ratio regulator is provided at the feeding port to adjust the feeding ratio of carbon dioxide micro-nano bubbles and fly ash to ensure maximum reaction efficiency. The outlet end of the mixing tube is connected to a cement stirring device through a pH detector, and a one-way valve is provided on the connecting pipe between the mixing tube and the cement stirring device to prevent liquid and gas backflow and ensure stable operation of the device.

[0016] The mixing tube body is made of 316L stainless steel seamless tube (Sch40 standard) with an aspect ratio of L / D = 5:1 to 8:1, and the tube body length is 300mm to ensure full contact between carbon dioxide and fly ash; the tube diameter is 50mm to prevent the aggregation of micro-nano bubbles due to the tube wall effect. The tube is composed of 3-6 groups of stainless steel spiral blades (angle 30°-45°) staggered and welded to the inner wall of the pipe. The length of each group of blades is 1.5D (the tube diameter D is 50mm), the thickness of the blades is 2-3mm, and the surface is polished to Ra≤0.8μm.

[0017] According to a preferred embodiment of the present invention, a cement mixing device includes a mixing drum, a motor B, and mixing blades. The motor B is provided at the top of the mixing drum, and the motor B is connected to the mixing blades provided inside the mixing drum. The mixing drum has a feed inlet at the top and a discharge outlet at the bottom. A display screen is provided on the outer wall of the mixing drum to display the test results of devices such as a pH meter, a bubble particle size analyzer, and a temperature sensor.

[0018] The working method of the above-mentioned efficient mineralization storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control is as follows:

[0019] (1) Deionized water is placed in the liquid storage tank, and then the device is moved to the construction area. The cement mixing device is connected to the raw material barrel. Cement, sand, stone, deionized water and other materials are placed in the raw material barrel in proportion;

[0020] (2) Turn on the high-pressure water pump and set the flow rate range to 1-5 L / min. Use the liquid flow controller to accurately adjust the liquid flow rate to ensure that it matches the gas flow rate. Turn on the cooling device and control the liquid temperature at 4-6°C to optimize the solubility of carbon dioxide and reaction efficiency.

[0021] (3) Open the valve of the carbon dioxide gas tank, introduce carbon dioxide industrial waste gas, accurately adjust the gas flow controller, set the gas flow rate to 0.40-0.60 L / min, adjust the pressure regulating valve to maintain the gas pressure stable, and ensure that the pressure of the gas is 0.1-0.3 MPa when entering the multimodal micro-nano bubble refinement device. Open the gas filter to remove impurities in the carbon dioxide gas to prevent clogging of the refinement device;

[0022] (4) Deionized water enters the micro-nano bubble generating device through a high-pressure water pump and is preliminarily mixed with the carbon dioxide gas. The micro-nano bubble generating device is turned on, and the rotating impeller speed is 1000-20000 rpm. The carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The ultrasonic vibration device has a frequency of 20-40 kHz, and the carbon dioxide gas is broken into micro-nano bubbles by cavitation effect. The carbon dioxide bubble liquid passes through a microporous membrane with a pore size of 0.1-10 μm, and the carbon dioxide gas is dispersed into a large number of micro-nano bubbles by physical filtration;

[0023] (5) Turn on the pH detector and temperature sensor to monitor the pH value and temperature of the reaction solution in real time to ensure the optimal reaction conditions; turn on the bubble particle size analyzer to detect the particle size distribution of micro-nano bubbles to ensure that the bubble diameter is between 100 nm and 500 nm;

[0024] (6) After the bubble size analyzer shows that the bubble diameter is between 100nm and 500nm, the ratio regulator is adjusted to set the ratio of carbon dioxide micro-nano bubbles to fly ash. The carbon dioxide micro-nano bubbles react with the free CaO or calcium aluminum silicate in the fly ash to generate nano-calcium carbonate that covers the surface of the fly ash particles, forming a porous or rough microstructure and increasing the specific surface area. The pretreated fly ash (containing nano-calcium carbonate) serves as the "crystal nucleus" of the subsequent cement carbonization, accelerating the CaO formation. 2+ The precipitation of CO32- improves the overall storage rate and efficiency, and the reactions that occur are as follows:

[0025] Carbon dioxide reacts with calcium oxide: CaO + CO2 → CaCO3;

[0026] Assume that the amount of carbon dioxide introduced is (unit: kg), the amount of fly ash fed is m FA (Unit: kg), the mass fraction of calcium source CaO in fly ash that reacts with carbon dioxide to form nano-calcium carbonate is ω1; the molar mass of carbon dioxide is The molar mass of CaO is M CaO =56 g / mol;

[0027] According to the chemical reaction stoichiometry, the amount of carbon dioxide that reacts with fly ash is:

[0028]

[0029] (7) When the pH value drops to 5.8-6.2, the solution is considered weakly acidic and the amount of carbon dioxide introduced is excessive, so the introduction of carbon dioxide gas is stopped;

[0030] (8) Open the one-way valve and let the gas-liquid mixture in the static mixer flow. The raw materials in the raw material barrel enter the cement mixing device. The cement mixing device is started to fully mix the CO2-fly ash complex with nano-calcium carbonate attached with cement slurry. Nano-calcium carbonate induces Ca2+ in the cement carbonization process. 2+ The amorphous calcium carbonate formed with CO32- transforms into a crystalline state, which promotes Ca 2+ It precipitates faster with CO32- and forms a stable calcium carbonate crystal structure, which accelerates the process of carbonization reaction. The calcium carbonate crystal nucleus is Ca 2+ The precipitation of CO32- provides a growth template, allowing them to be arranged in a certain crystal structure and direction, promoting the precipitation reaction, thereby efficiently sealing carbon dioxide in cement-based materials. The reactions that occur are as follows:

[0031] Carbon dioxide reacts with dicalcium silicate: 2CaO·SiO2+2CO2+H2O→2CaCO3+H2SiCO3

[0032] Carbon dioxide reacts with tricalcium silicate: 3CaO·SiO2+3CO2+H2O→3CaCO3+H2SiCO3

[0033] Carbon dioxide reacts with calcium hydroxide: Ca(OH)2+CO2→CaCO3+H2O

[0034] Carbon dioxide reacts with CSH gel: CaO·SiO2·H2O+CO2→CaCO3+H2SiCO3

[0035] Assume that the cement input is m C (Unit: kg), the mass fraction of dicalcium silicate in cement clinker is ω2, the mass fraction of tricalcium silicate is ω3, the mass fraction of calcium hydroxide in cement hydration products is ω4, and the mass fraction of the part of CSH gel equivalent to CaO participating in the reaction is ω5;

[0036] The molar mass of dicalcium silicate is M1 = 286.44 g / mol, the molar mass of tricalcium silicate is M2 = 228.31 g / mol, and the molar mass of calcium hydroxide is M3 = 74.09 g / mol;

[0037] According to the chemical reaction stoichiometry, the amount of carbon dioxide that reacts with each component in cement is:

[0038]

[0039] The total amount of carbon dioxide:

[0040]

[0041] It can be concluded that the proportional relationship between the amount of carbon dioxide introduced, the amount of fly ash introduced, and the amount of cement introduced is:

[0042]

[0043] According to the above-mentioned stoichiometric relationship, in the fly ash pretreatment stage (reaction of carbon dioxide with fly ash), when the CaO mass fraction in the fly ash is 20%, m FA =1:10; in the cement mineralization stage (when the active components in cement account for 70%), m C =1:15. Taking into account the reaction requirements of the two stages, the present invention proposes that the optimal total ratio of the overall system is 1:10:15. In actual application, it can be fine-tuned according to the fluctuation of raw material composition.

[0044] The present invention is based on multimodal micro-nano bubble refinement technology. First, carbon dioxide gas is highly refined and dissolved in water to prepare carbon dioxide micro-nano bubbles with extremely small pore size and high uniformity. The bubbles are then transported to a static pipeline mixer, where they fully contact and react with fly ash powder to generate nano-calcium carbonate that adheres to the surface of the fly ash, increasing the specific surface area and forming a "CO2-fly ash complex" with a nano-calcium carbonate surface. The complex is then introduced into a cement mixing device. The complex serves as the "crystal nucleus" for subsequent cement carbonization, providing calcium carbonate nucleation sites and accelerating the carbonization reaction of cement and hydration products, namely CaCO3. 2+ The precipitation of CO32- improves the overall storage rate and efficiency, and realizes the efficient storage of carbon dioxide in cement-based materials.

[0045] The beneficial effects of the present invention are:

[0046] 1. The present invention utilizes a multimodal micro-nano bubble generation device, utilizing a triple-technology combination of a rotating impeller, an ultrasonic vibration device, and a microporous membrane to overcome the limitations of a single technology. The high-speed impeller initially refines the bubbles through shear force; the ultrasonic vibrator further breaks the bubbles down to the submicron level through cavitation; and the microporous membrane ultimately filters and generates uniform micro-nano bubbles. This overcomes the drawbacks of single technologies, such as uneven bubble size, poor stability, or high energy consumption, by efficiently generating micro-nano bubbles with a smaller particle size (100-500nm) and more uniform distribution. It also improves CO2 dissolution efficiency (by over 30%) and reaction activity, while reducing energy consumption by 20%-40%. Its integrated design can also adapt to complex working conditions (such as fly ash suspensions), ensuring long-term stability of bubble generation and mineralization reactions, achieving precise control and efficient utilization of CO2, and avoiding the escape and waste of CO2 when it is directly introduced into cement slurry.

[0047] 2. The present invention proposes the optimal dynamic stoichiometric ratio of the CO2-fly ash-cement ternary system through innovative chemical reaction stoichiometry, establishes a precise calculation formula based on raw material components (ω1~ω5), and increases the CO2 storage efficiency from the traditional 60% to more than 90%; by real-time matching of the fly ash CaO content with the active components of cement, the raw material utilization rate is increased by 40% (fly ash consumption >90%, cement strength increases by 10%), and establishes a precise proportional relationship between the carbon dioxide input, fly ash input and cement input, ensuring the maximization of the mineralization reaction efficiency.

[0048] 3. The present invention adopts a dynamic ratio regulation system. The ratio regulator (20) of the static pipeline mixer is used to optimize the feeding ratio in real time. Combined with the feedback of the pH sensor, the mixing ratio of carbon dioxide and fly ash is dynamically adjusted to ensure that the pH of the reaction solution is stable in the weak acid range of 5.8 to 6.2, thereby realizing intelligent dynamic regulation of the feeding ratio of CO2, fly ash and cement. The system automatically adjusts the feeding amount of each material based on the established stoichiometric model by collecting multi-dimensional data such as pH value, temperature, bubble particle size in real time to ensure that the reaction is always in the optimal stoichiometric ratio (such as mCO2:mFA:mC=1:10:15). Compared with the traditional fixed ratio feeding method, the system can immediately respond to interference factors such as fluctuations in raw material composition (such as changes in CaO content in fly ash by ±5%) and changes in ambient temperature (±2°C). Through closed-loop feedback, the reaction conditions are stably controlled in the optimal range (pH 5.8-6.2). Practical applications have shown that this dynamic adjustment can increase the CO2 mineralization efficiency by more than 50%, the raw material utilization rate by 20-30%, and the reaction stability by 80%. It effectively solves the problems of CO2 escape (>15%) or incomplete reaction (<60%) caused by imbalance in proportions in traditional processes, and realizes the precision and efficiency of the carbon fixation process of cement-based materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a structural schematic diagram of the present invention;

[0050] Figure 2 Schematic diagram of the structure of the micro-nano bubble generating device of the present invention;

[0051] Among them: 1-frame, 2-controller, 3-gas tank, 4-gas flow controller, 5-pressure regulating valve, 6-gas filter, 7-liquid storage tank, 8-air inlet, 9-motor A, 10-cooling device, 11-high-pressure water pump, 12-liquid flow controller, 13-ultrasonic vibration device, 14-liquid inlet, 15-housing, 16-microporous membrane, 17-liquid outlet, 18-temperature sensor, 19-bubble particle size analyzer, 20-proportional regulator, 21-feeding port, 22-mixing tube, 23-pH detector, 24-motor B, 25-feeding port, 26-display screen, 27-discharge port, 28-rotating impeller. DETAILED DESCRIPTION

[0052] The present invention will be further described below with reference to embodiments and accompanying drawings, but is not limited thereto.

[0053] Example 1:

[0054] like Figure 1-2 As shown, this embodiment provides a high-efficiency mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic proportion control, including a frame 1, a multimodal micro-nano bubble refinement device, a static mixer, a cement stirring device and a controller. The frame is provided with a multimodal micro-nano bubble refinement device, a cement stirring device and a controller. The multimodal micro-nano bubble refinement device is connected to the cement stirring device through the static mixer, and the multimodal micro-nano bubble refinement device, the static mixer and the cement stirring device are all connected to the controller.

[0055] The multimodal micro-nano bubble refinement device includes a carbon dioxide intake device, a micro-nano bubble generating device and a liquid delivery device. The carbon dioxide intake device and the liquid delivery device are respectively connected to the micro-nano bubble generating device, and the micro-nano bubble generating device is connected to a static mixer.

[0056] The micro-nano bubble generating device includes a shell 15, a motor A9, a rotating impeller 28, an ultrasonic vibration device 13 and a microporous membrane 16. The rotating impeller 28 is provided at the bottom of the shell 15, and the rotating impeller 28 is externally connected to the motor A9. The ultrasonic vibration device 13 is provided in the middle of the shell 15, and the microporous membrane 16 is provided on the upper part of the shell 15. The two sides of the top of the shell 15 are respectively connected to the liquid conveying device and the static mixer through the liquid inlet 14 and the liquid outlet 17. The bottom of the shell 15 is connected to the carbon dioxide intake device through the air inlet 8.

[0057] The rotating impeller rotates at a speed of 1000 to 20000 rpm, cutting the carbon dioxide gas into micro-nano bubbles through high-speed shear force. The impeller is made of corrosion-resistant stainless steel or ceramic to adapt to weakly acidic environments. The ultrasonic vibration device has a frequency of 20 to 40 kHz, breaking the carbon dioxide gas into micro-nano bubbles through the cavitation effect. The ultrasonic vibrator is preferably made of piezoelectric ceramic material with high energy conversion efficiency. The microporous membrane uses a microporous membrane with a pore size of 0.1 to 10 μm, and disperses the carbon dioxide gas into micro-nano bubbles through physical filtration. The membrane material is polytetrafluoroethylene (PTFE), which has high chemical stability and low surface energy.

[0058] A temperature sensor 18 and a bubble particle size analyzer 19 are provided on the connecting pipe between the housing 15 and the static mixer.

[0059] The carbon dioxide intake device includes a gas tank 3 for storing carbon dioxide, a gas flow controller 4 and a gas filter 6. The gas tank 3 is connected to a micro-nano bubble generating device through the gas flow controller 4 and the gas filter 6. A pressure regulating valve 5 is provided on the gas tank 3. The gas flow controller is EL-FLOW series gas flow controller, gas filter for Acro 50 series gas filter model AP020F50S.

[0060] The liquid conveying device includes a liquid storage tank 7, a cooling device 10 and a high-pressure water pump 11 connected in sequence. The water outlet of the high-pressure water pump 11 is connected to the micro-nano bubble generating device through a liquid flow controller 12. The liquid storage tank 7 has a capacity of 20L and stores deionized water as a carbon dioxide dissolving medium; the high-pressure water pump 11 transports deionized water into the micro-nano bubble generating device; the liquid flow controller 12 accurately adjusts the liquid flow to ensure that it matches the gas flow, and the cooling device 10 controls the liquid temperature to optimize the solubility and reaction efficiency of carbon dioxide.

[0061] The static mixer includes a mixing tube 22, which is provided with a feeding port 21. The feeding port extends into the mixing tube at 1 / 30, which improves the mixing effect without causing corrosion of the feeding port. A flow rate difference of 5:1 is formed between the feeding port and the feeding port of the mixing tube to enhance mixing. A ratio regulator 20 is provided at the feeding port 21 to adjust the ratio of carbon dioxide micro-nano bubbles and fly ash to ensure maximum reaction efficiency. The outlet end of the mixing tube 22 is connected to a cement stirring device through a pH detector 23. A one-way valve is also provided on the connecting pipe between the mixing tube and the cement stirring device to prevent liquid and gas backflow and ensure stable operation of the device.

[0062] The mixing tube body is made of 316L stainless steel seamless tube (Sch40 standard) with an aspect ratio of L / D = 5:1 to 8:1, and the tube body length is 300mm to ensure full contact between carbon dioxide and fly ash; the tube diameter is 50mm to prevent the aggregation of micro-nano bubbles due to the tube wall effect. The tube is composed of 3-6 groups of stainless steel spiral blades (angle 30°-45°) staggered and welded to the inner wall of the pipe. The length of each group of blades is 1.5D (the tube diameter D is 50mm), the thickness of the blades is 2-3mm, and the surface is polished to Ra≤0.8μm.

[0063] The cement mixing device includes a mixing drum, motor B24, and mixing blades. Motor B is located at the top of the mixing drum, connected to the mixing blades inside. A feed port 25 is located at the top of the drum, and a discharge port 27 is located at the bottom. A display screen 26 is located on the outer wall of the drum, displaying test results from devices such as a pH meter, bubble size analyzer, and temperature sensor.

[0064] The working method of the above-mentioned efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control is applied to urban construction sites, and the steps are as follows:

[0065] (1) Deionized water is placed in the liquid storage tank, and then the device is moved to the construction area. The cement mixing device is connected to the raw material barrel. Cement, sand, stone, deionized water and other materials are placed in the raw material barrel in proportion;

[0066] (2) Turn on the high-pressure water pump, set the flow rate to 3 L / min, turn on the cooling device, and control the liquid temperature at 5°C;

[0067] (3) Open the valve of the carbon dioxide gas tank and introduce carbon dioxide industrial waste gas. The gas flow rate is set to 0.5 L / min. Adjust the pressure regulating valve to maintain the gas pressure at 0.2 MPa.

[0068] (4) Deionized water enters the micro-nano bubble generating device through a high-pressure water pump and is preliminarily mixed with the carbon dioxide gas. The micro-nano bubble generating device is turned on, and the rotating impeller speed is 15,000 rpm. The carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The ultrasonic vibration device frequency is 30 kHz, and the carbon dioxide gas is broken into micro-nano bubbles by cavitation effect. The carbon dioxide bubble liquid passes through a microporous membrane with a pore size of 0.1 to 10 μm, and the carbon dioxide gas is dispersed into a large number of micro-nano bubbles by physical filtration;

[0069] (5) Turn on the pH detector and temperature sensor to monitor the pH value and temperature of the reaction solution in real time;

[0070] (6) adjusting the ratio regulator to set the ratio of carbon dioxide micro-nano bubbles to fly ash to 1:10;

[0071] (7) Mix the pretreated fly ash with cement, sand, stone and deionized water in proportion, and start the cement mixing device;

[0072] (8) When the pH value drops to 6.0, stop the carbon dioxide injection.

[0073] Using the above working method, the diameter of the micro-nano bubbles is stabilized at around 200nm, the carbon dioxide storage efficiency reaches 90%, and the compressive strength of the cement-based material is increased by 10%.

[0074] Example 2:

[0075] A method for operating a high-efficiency mineralized CO2 storage device based on multimodal micro-nano bubble generation and dynamic ratio control as described in Example 1 is applied to an industrial solid waste treatment plant, and the steps are as follows:

[0076] (1) Deionized water is placed in the liquid storage tank, and then the device is moved to the construction area. The cement mixing device is connected to the raw material barrel. Cement, sand, stone, deionized water and other materials are placed in the raw material barrel in proportion;

[0077] (2) Turn on the high-pressure water pump, set the flow rate to 2 L / min, turn on the cooling device, and control the liquid temperature at 4°C;

[0078] (3) Open the valve of the carbon dioxide gas tank and introduce carbon dioxide industrial waste gas. The gas flow rate is set to 0.45 L / min. Adjust the pressure regulating valve to maintain the gas pressure at 0.15 MPa.

[0079] (4) Deionized water enters the micro-nano bubble generating device through a high-pressure water pump and is preliminarily mixed with carbon dioxide gas. The micro-nano bubble generating device is turned on, and the rotating impeller speed is 10,000 rpm. The carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The ultrasonic vibration device frequency is 25 kHz, and the carbon dioxide gas is broken into micro-nano bubbles by cavitation effect. The carbon dioxide bubble liquid passes through a microporous membrane with a pore size of 0.1 to 10 μm, and the carbon dioxide gas is dispersed into a large number of micro-nano bubbles by physical filtration;

[0080] (5) Turn on the pH detector and temperature sensor to monitor the pH value and temperature of the reaction solution in real time;

[0081] (6) adjusting the ratio regulator to set the ratio of carbon dioxide micro-nano bubbles to fly ash to 1:8;

[0082] (7) Mix the pretreated fly ash with cement, sand, stone and deionized water in proportion, and start the cement mixing device;

[0083] (8) When the pH value drops to 5.9, stop the carbon dioxide injection.

[0084] Using this method, the diameter of micro-nano bubbles stabilized at around 300nm, fly ash utilization increased by 20%, and the durability of cement-based materials was significantly enhanced.

[0085] Example 3:

[0086] A method for operating a high-efficiency mineralized CO2 storage device based on multimodal micro-nano bubble generation and dynamic ratio control as described in Example 1 is applied to an industrial solid waste treatment plant, and the steps are as follows:

[0087] (1) Deionized water is placed in the liquid storage tank, and then the device is moved to the construction area. The cement mixing device is connected to the raw material barrel. Cement, sand, stone, deionized water and other materials are placed in the raw material barrel in proportion;

[0088] (2) Turn on the high-pressure water pump, set the flow rate to 4 L / min, turn on the cooling device, and control the liquid temperature at 6°C;

[0089] (3) Open the valve of the carbon dioxide gas tank and introduce carbon dioxide industrial waste gas. The gas flow rate is set to 0.55 L / min. Adjust the pressure regulating valve to maintain the gas pressure at 0.25 MPa.

[0090] (4) Deionized water enters the micro-nano bubble generating device through a high-pressure water pump and is preliminarily mixed with the carbon dioxide gas. The micro-nano bubble generating device is turned on, and the rotating impeller speed is 18,000 rpm. The carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The ultrasonic vibration device frequency is 35 kHz, and the carbon dioxide gas is broken into micro-nano bubbles by cavitation effect. The carbon dioxide bubble liquid passes through a microporous membrane with a pore size of 0.1 to 10 μm, and the carbon dioxide gas is dispersed into a large number of micro-nano bubbles by physical filtration;

[0091] (5) Turn on the pH detector and temperature sensor to monitor the pH value and temperature of the reaction solution in real time;

[0092] (6) adjusting the ratio regulator to set the ratio of carbon dioxide micro-nano bubbles to fly ash to 1:12;

[0093] (7) Mix the pretreated fly ash with cement, sand, stone and deionized water in proportion, and start the cement mixing device;

[0094] (8) When the pH value drops to 6.1, stop the carbon dioxide injection.

[0095] Using this method, the diameter of the micro-nano bubbles stabilized at around 400nm, the carbon dioxide sequestration efficiency reached 85%, and the strength of the cement-based material increased by 15%.

[0096] Example 4:

[0097] A method for operating a high-efficiency mineralized CO2 storage device based on multimodal micro-nano bubble generation and dynamic ratio control as described in Example 1 is applied to an industrial solid waste treatment plant, and the steps are as follows:

[0098] (1) Deionized water is placed in the liquid storage tank, and then the device is moved to the construction area. The cement mixing device is connected to the raw material barrel. Cement, sand, stone, deionized water and other materials are placed in the raw material barrel in proportion;

[0099] (2) Turn on the high-pressure water pump, set the flow range to 1 L / min, turn on the cooling device, and control the liquid temperature at 4°C;

[0100] (3) Open the valve of the carbon dioxide gas tank and introduce carbon dioxide industrial waste gas. The gas flow rate is set to 0.4 L / min. Adjust the pressure regulating valve to maintain the gas pressure at 0.1 MPa.

[0101] (4) Deionized water enters the micro-nano bubble generating device through a high-pressure water pump and is preliminarily mixed with carbon dioxide gas. The micro-nano bubble generating device is turned on, and the rotating impeller speed is 5000 rpm. The carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The ultrasonic vibration device frequency is 20 kHz, and the carbon dioxide gas is broken into micro-nano bubbles by cavitation effect. The carbon dioxide bubble liquid passes through a microporous membrane with a pore size of 0.1 to 10 μm, and the carbon dioxide gas is dispersed into a large number of micro-nano bubbles by physical filtration;

[0102] (5) Turn on the pH detector and temperature sensor to monitor the pH value and temperature of the reaction solution in real time;

[0103] (6) adjusting the ratio regulator to set the ratio of carbon dioxide micro-nano bubbles to fly ash to 1:5;

[0104] (7) Mix the pretreated fly ash with cement, sand, stone and deionized water in proportion, and start the cement mixing device;

[0105] (8) When the pH value drops to 5.8, stop the carbon dioxide injection.

[0106] Using this method, the diameter of the micro-nano bubbles stabilized at around 100 nm, and the carbon dioxide sequestration efficiency reached 95%. Experimental data verified the feasibility and efficiency of the invention.

Claims

1. A highly efficient mineralized CO2 storage device based on multimodal micro-nano bubble generation and dynamic ratio control, characterized in that: The invention comprises a vehicle frame, a multimodal micro-nano bubble refinement device, a static mixer, a cement stirring device and a controller. The vehicle frame is provided with the multimodal micro-nano bubble refinement device, the cement stirring device and the controller. The multimodal micro-nano bubble refinement device is connected to the cement stirring device via the static mixer. The multimodal micro-nano bubble refinement device, the static mixer and the cement stirring device are all connected to the controller.

2. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 1 is characterized in that: The multimodal micro-nano bubble refinement device includes a carbon dioxide intake device, a micro-nano bubble generating device and a liquid delivery device. The carbon dioxide intake device and the liquid delivery device are respectively connected to the micro-nano bubble generating device, and the micro-nano bubble generating device is connected to a static mixer.

3. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 2 is characterized in that: The micro-nano bubble generating device includes a shell, a motor A, a rotating impeller, an ultrasonic vibration device and a microporous membrane. The rotating impeller is provided at the bottom of the shell, and the rotating impeller is externally connected to the motor A. The ultrasonic vibration device is provided in the middle of the shell, and the microporous membrane is provided on the upper part of the shell. The liquid conveying device and the static mixer are respectively connected to the two sides of the top of the shell, and the carbon dioxide intake device is connected to the bottom of the shell.

4. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 3 is characterized in that: A temperature sensor and a bubble particle size analyzer are provided on the connecting pipe between the shell and the static mixer.

5. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 4 is characterized in that: The carbon dioxide intake device includes a gas tank for storing carbon dioxide, a gas flow controller and a gas filter. The gas tank is connected to a micro-nano bubble generating device through the gas flow controller and the gas filter, and a pressure regulating valve is provided on the gas tank.

6. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 5, characterized in that: The liquid delivery device comprises a liquid storage tank, a cooling device and a high-pressure water pump which are connected in sequence, and the water outlet of the high-pressure water pump is connected to the micro-nano bubble generating device through a liquid flow controller.

7. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 6, characterized in that: The static mixer includes a mixing tube, which is provided with a feeding port. A ratio regulator is provided at the feeding port. The outlet end of the mixing tube is connected to a cement stirring device through a pH detector. A one-way valve is also provided on the connecting pipe between the mixing tube and the cement stirring device.

8. The efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 7, characterized in that: The cement mixing device includes a mixing drum, a motor B and mixing blades. The motor B is provided on the top of the mixing drum, and the motor B is connected to the mixing blades provided in the mixing drum. The upper part of the mixing drum is provided with a feed port, and the bottom of the mixing drum is provided with a discharge port.

9. The working method of the efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 8, characterized in that: Here are the steps: (1) Deionized water is placed in the liquid storage tank, and then the device is moved to the construction area. The cement mixing device is connected to the raw material cylinder, and cement, sand, stone, and deionized water are placed in the raw material cylinder in proportion; (2) Turn on the high-pressure water pump, set the flow rate range to 1-5 L / min, turn on the cooling device, and control the liquid temperature at 4-6 °C; (3) Open the valve of the carbon dioxide gas tank and introduce carbon dioxide industrial waste gas. The gas flow rate is set to 0.40-0.60 L / min. Adjust the pressure regulating valve to maintain a stable gas pressure to ensure that the pressure of the gas is 0.1-0.3 MPa when it enters the multimodal micro-nano bubble refinement device. Open the gas filter to remove impurities in the carbon dioxide gas. (4) Deionized water enters the micro-nano bubble generating device through a high-pressure water pump and is preliminarily mixed with the carbon dioxide gas. The micro-nano bubble generating device is turned on, and the rotating impeller speed is 1000-20000 rpm. The carbon dioxide gas is cut into micro-nano bubbles by high-speed shear force. The ultrasonic vibration device has a frequency of 20-40 kHz, and the carbon dioxide gas is broken into micro-nano bubbles by cavitation effect. The carbon dioxide bubble liquid passes through a microporous membrane with a pore size of 0.1-10 μm, and the carbon dioxide gas is dispersed into a large number of micro-nano bubbles by physical filtration; (5) Turn on the pH detector and temperature sensor to monitor the pH value and temperature of the reaction solution in real time to ensure the optimal reaction conditions; turn on the bubble particle size analyzer to detect the particle size distribution of micro-nano bubbles to ensure that the bubble diameter is between 100 nm and 500 nm; (6) After the bubble size analyzer shows that the bubble diameter is between 100nm and 500nm, the ratio regulator is adjusted to set the ratio of carbon dioxide micro-nano bubbles to fly ash. The carbon dioxide micro-nano bubbles react with the free CaO or calcium aluminum silicate in the fly ash to generate nano calcium carbonate that covers the surface of the fly ash particles, forming a porous or rough microstructure and increasing the specific surface area. The pretreated fly ash accelerates the CaO 2+ With the precipitation of CO32-, the reaction occurs as follows: Carbon dioxide reacts with calcium oxide: CaO + CO2 → CaCO3; Assume that the amount of carbon dioxide introduced is The amount of fly ash fed is m FA The mass fraction of calcium source CaO in fly ash that reacts with carbon dioxide to form nano-calcium carbonate is ω1; the molar mass of carbon dioxide is The molar mass of CaO is M CaO =56 g / mol; According to the chemical reaction stoichiometry, the amount of carbon dioxide that reacts with fly ash is: (7) When the pH value drops to 5.8-6.2, the solution is considered weakly acidic and the amount of carbon dioxide introduced is excessive, so the introduction of carbon dioxide gas is stopped; (8) Open the one-way valve and allow the gas-liquid mixture in the static mixer to flow in. The raw materials in the raw material barrel enter the cement mixing device. The cement mixing device is started to fully mix the CO2-fly ash complex with nano-calcium carbonate attached with the cement slurry to complete the preparation.

10. The working method of the efficient mineralization and storage CO2 device based on multimodal micro-nano bubble generation and dynamic ratio control according to claim 9, characterized in that: In step (8), nano calcium carbonate induces Ca 2+ The amorphous calcium carbonate formed with CO32- transforms into a crystalline state, which promotes Ca 2+ It precipitates faster with CO32- and forms a stable calcium carbonate crystal structure, which accelerates the process of carbonization reaction. The calcium carbonate crystal nucleus is Ca 2+ The precipitation of CO32- provides a growth template, allowing them to be arranged in a certain crystal structure and direction. The reactions that occur are as follows: Carbon dioxide reacts with dicalcium silicate: 2CaO·SiO2+2CO2+H2O→2CaCO3+H2SiCO3 Carbon dioxide reacts with tricalcium silicate: 3CaO·SiO2+3CO2+H2O→3CaCO3+H2SiCO3 Carbon dioxide reacts with calcium hydroxide: Ca(OH)2+CO2→CaCO3+H2O Carbon dioxide reacts with CSH gel: CaO·SiO2·H2O+CO2→CaCO3+H2SiCO3 Assume that the cement input is m C , the mass fraction of dicalcium silicate in cement clinker is ω2, the mass fraction of tricalcium silicate is ω3, the mass fraction of calcium hydroxide in cement hydration products is ω4, and the mass fraction of the part of CSH gel equivalent to CaO participating in the reaction is ω5; The molar mass of dicalcium silicate is M1 = 286.44 g / mol, the molar mass of tricalcium silicate is M2 = 228.31 g / mol, and the molar mass of calcium hydroxide is M3 = 74.09 g / mol; According to the chemical reaction stoichiometry, the amount of carbon dioxide that reacts with each component in cement is: The total amount of carbon dioxide: It can be concluded that the proportional relationship between the amount of carbon dioxide introduced, the amount of fly ash introduced, and the amount of cement introduced is:

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