Alkaline solid waste liquid-phase mineralization carbon sequestration bubbling bed device and method

Abstract

The invention belongs to the technical field of liquid-phase mineralization carbon sequestration, and particularly relates to a bubbling bed device and method for liquid-phase mineralization carbon sequestration of alkaline solid waste, and the device comprises a gas-liquid-solid bubbling bed reactor body and a measuring device; wherein the bubbling bed reactor body comprises a reaction material inlet / outlet, a flow observation window and the like; the measuring device comprises a CO2 sensor, a pressure sensor, a pH meter, a conductivity probe, a flow image acquisition device, a data acquisition card and the like; important parameters of flow, mass transfer and reaction in a liquid-phase mineralization carbon sequestration reaction flow are obtained by monitoring data such as a reaction flow image, pressure pulsation data, pH, conductivity and CO2 concentration in exhaust gas after reaction in real time; the operation performance of the bubbling bed reactor is regulated and controlled by obtaining important parameters of the reaction flow, and the efficient liquid-phase mineralization carbon sequestration process is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of liquid phase mineralization carbon fixation, and specifically relates to a bubbling bed device and method for direct liquid phase mineralization carbon fixation of alkaline solid waste. Background Art

[0002] The combustion of fossil fuels has caused a large amount of greenhouse gas emissions. The increase in the concentration of carbon dioxide in the atmosphere has exacerbated global climate change. Therefore, it is very important to develop safe and reliable carbon reduction technologies to deal with the problem of excessive CO2 emissions. Mineralized carbon fixation technology is one of the CO2 capture, storage and utilization (CCUS) technologies. This technology reacts Ca or Mg-containing materials with CO2 to generate stable carbonates to achieve the purpose of carbon fixation. This technology has two pathways: direct mineralization carbon fixation and indirect mineralization carbon fixation. Among them, direct mineralization carbon fixation technology can be divided into dry pathways and wet pathways. Among them, the direct liquid phase mineralization carbon fixation route is considered to be a better route due to its low cost and simple operation method. This technology is divided into mineral carbonation carbon fixation technology and alkaline solid waste carbonation carbon fixation technology according to the selected solid phase material. my country produces a large amount of alkaline solid waste every year. Solid waste is generally treated by open-air stacking or landfill, which will lead to waste and pollution of land resources. Therefore, selecting alkaline solid waste as a material for liquid phase mineralization carbon fixation can promote the recycling of the substance.

[0003] Existing direct liquid phase mineralization carbon fixation technology has disadvantages such as slow reaction rate and low carbon fixation amount, so it is necessary to pre-treat the raw materials for mineralization carbon fixation, including mechanical activation, thermal activation, etc. However, the energy consumption of pre-treating raw materials is high, and direct treatment at room temperature and pressure has problems such as slow rate and low efficiency. Therefore, it is an important development goal to select suitable alkaline solid waste to achieve efficient direct liquid phase mineralization carbon fixation process at room temperature and pressure. Summary of the invention

[0004] Based on the national demand for carbon emission reduction and the technical background of resource utilization of alkaline solid waste, the present invention focuses on the technical problem of how to achieve liquid phase mineralization and carbon fixation with high efficiency and low energy consumption, and discloses a device and process parameter monitoring method suitable for direct liquid phase mineralization and carbon fixation of alkaline solid waste.

[0005] By designing a gas-liquid-solid bubbling bed reactor, good mixing and mass transfer of CO2 and alkaline solid waste slurry can be achieved to obtain a higher carbon fixation amount. By selecting alkaline solid waste with high content of CaO and MgO, carbon fixation technology under low energy consumption conditions can be achieved. The important parameters of the reaction process in this technology are monitored to obtain the operating values ​​of the reaction flow, mass transfer and reaction parameters, providing guidance for the reactor scale-up and industrial application of this technology.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] The present invention provides a bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste. The device comprises a bubbling bed reactor and a measuring device. The bubbling bed reactor body is used for performing direct liquid phase mineralization and carbon fixation reaction of alkaline solid waste; the measuring device is used for collecting pressure pulsation signals, pH, conductivity values ​​and CO2 concentration of reactor outlet gas in the bubbling bed reactor.

[0008] The upper part of the bubbling bed reactor is provided with a solid-liquid phase feed port, a gas outlet and a flow observation window, and the gas outlet is connected to a CO2 sensor; the bottom of the bubbling bed reactor is provided with an air distribution plate, a gas inlet and a first reaction slurry outlet, the gas inlet is connected to a flow meter through a gas mixer, the first gas flow meter, the second gas flow meter and the third gas flow meter are respectively connected to a gas cylinder, and the gas enters the gas mixer at a certain flow rate through the gas flow meter from different gas cylinders, and finally enters the gas inlet; a second reaction slurry outlet and a pressure sensor are provided on one side of the bubbling bed reactor, and a sampling port and a ruler are provided on the other side of the bubbling bed reactor.

[0009] Furthermore, the measuring device includes a pH meter, a conductivity probe, a pressure sensor, and a CO2 sensor arranged on the side of the bubbling bed reactor; two sampling ports and a ruler are arranged on the right side of the bubbling bed reactor, the sampling ports are connected to the bubbling bed reactor through a pump, the two sampling ports are respectively provided with a first pH meter, a second pH meter, a first conductivity probe, and a second conductivity probe, and the ruler is pasted on the right side of the bubbling bed; the first pressure sensor, the second pressure sensor, and the third pressure sensor are arranged at three different axial positions on the left side of the bubbling bed reactor. The bubbling bed device also includes a touch screen controller with adjustable parameters, and all data are stored in a computer via a data acquisition card.

[0010] Furthermore, the first pH meter, the second pH meter, the first conductivity probe, and the second conductivity probe are arranged on the right side of the bubbling bed reactor to measure the pH and conductivity values ​​of the reaction slurry obtained by the pump; the three pressure sensors (the first pressure sensor, the second pressure sensor, and the third pressure sensor) are arranged on the left side of the bubbling bed reactor, with heights of 3.8 cm, 15.1 cm, and 23.8 cm, respectively, to measure the pressures at different bed heights in the bed; the CO2 sensor is connected to the gas outlet at the top of the bubbling bed reactor to measure the CO2 concentration of the reactor outlet gas; the touch screen controller with adjustable parameters and the computer are used to control the flow rate and CO2 concentration of the inlet gas and store the data measured during the reaction; the ruler is pasted on the right side of the bubbling bed to read the bed height before and after the reaction.

[0011] Furthermore, a fourth gas flow meter and a desiccant are provided between the CO2 sensor and the gas outlet.

[0012] The present invention also provides a method for monitoring important parameters of flow, mass transfer and reaction during the operation of an alkaline solid waste direct liquid phase mineralization carbon fixation bubbling bed device, and the specific steps are as follows:

[0013] (1) Solid and liquid materials of a certain ratio are sequentially added into the bubbling reactor through the solid and liquid feed ports at the top of the bubbling bed reactor, and the inlet CO2 concentration y of the mixed gas of CO2 and N2 passing through the gas inlet is set by the touch screen controller (12). in and volume flow rate Q in After that, N2 is passed for a period of time. When the pH of the mixed slurry of solid phase and liquid phase is greater than 12.5, it is considered to be uniformly mixed. Then, a mixed gas of CO2 and N2 with a specified volume flow rate is passed.

[0014] (2) Mixing and reacting the gas-liquid-solid three-phase in the bubbling bed reactor, and collecting the pressure pulsation signal, pH value and CO2 concentration y of the slurry in the bubbling bed reactor in real time through the first pH meter, the second pH meter, the first conductivity probe, the second conductivity probe, the first pressure sensor, the second pressure sensor, the third pressure sensor and the CO2 sensor. out All data were collected and stored in the computer via a data acquisition card. The reaction was considered to be complete when the pH of the slurry was lower than 6. After the reaction, a portion of the slurry was taken out for thermogravimetric analysis.

[0015] (3) Performing time-frequency domain analysis on the measured pressure pulsation signal, obtaining EMD energy entropy to characterize the flow pattern data and thus determine the flow pattern in the bubbling bed reactor; by reading the liquid level before and after the reaction, the gas holdup in the bubbling bed can be obtained as shown in formula (1); at the same time, the bubble size distribution can be obtained by processing the flow image using image pro plus;

[0016]

[0017] Where H represents the bed height after the mixed gas is introduced, m; H0 represents the bed height when no gas is introduced, m; ε g Indicates the gas holdup in the bubbling bed;

[0018] (4) The mass transfer parameters monitored during the liquid phase mineralization carbon fixation process include: gas phase side mass transfer coefficient k L a and liquid side mass transfer coefficient k G a; The mass transfer coefficient is monitored in real time by the outlet gas CO2 concentration; the calculation formula is shown in equations (2) and (3):

[0019]

[0020] Among them, in formula (2) and formula (3), and represents the molar ratio of CO2 to N2 at the inlet and outlet of the bubbling bed reactor; V L Indicates the volume of liquid phase added, L; P in and P out represents the CO2 partial pressure at the gas inlet and outlet of the bubbling bed reactor, MPa; H represents the Henry coefficient of CO2 in water at normal temperature and pressure, which is 0.338 mol / (L·Mpa);

[0021] (5) The reaction parameters monitored in the liquid phase mineralization carbon fixation process include pH, conductivity and carbonation efficiency; the time point and pH value of complete precipitation of the carbonation reaction are analyzed by drawing pH and conductivity curves; the carbonation efficiency value is calculated by thermogravimetric analysis and CO2 concentration at the gas inlet and gas outlet, as shown in formula (4)(5);

[0022]

[0023] In formula (4), η is the carbonation efficiency of alkaline solid waste, the original mass is m1, in TG analysis, the mass percentage of Ca(OH)2 in the unreacted solid waste completely decomposed at 300-500℃ is A1, the mass of the product after carbonation reaction is m2, and the mass reduction percentage of Ca(OH)2 in the alkaline solid waste after reaction is defined as A 2。

[0024] In formula (5) is the total amount of CO2 introduced, mol; is the total amount of CO2 in the gas discharged from the gas outlet after the reaction, mol; is the amount of Ca(OH)2 in the alkaline solid waste before the reaction, mol.

[0025] The beneficial effects of the present invention are:

[0026] The present invention proposes a bubbling bed device for mineralization and carbon fixation of alkaline solid waste. The device is mainly composed of a bubbling bed reaction system and a collection and analysis system. The device can realize direct liquid-phase mineralization and carbon fixation of alkaline solid waste at normal temperature and pressure, and after setting up real-time monitoring devices such as CO2 sensors, conductivity and pH probes, and pressure sensors, the reactor can monitor important parameters in the reaction process in real time to obtain the operating values ​​of reaction flow, mass transfer, and reaction parameters, providing guidance for the reactor amplification and industrial application of the technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural diagram of the device of the present invention;

[0028] Figure 2The EMD energy entropy curve diagram shown in the embodiment of the present invention;

[0029] Figure 3 A graph showing the change of gas holdup with liquid-to-solid ratio in an embodiment of the present invention;

[0030] Figure 4 A graph showing the mass transfer coefficient changing with time and liquid-to-solid ratio according to an embodiment of the present invention;

[0031] Figure 5 The graph of pH, conductivity and outlet gas CO2 concentration changing with time shown in the example of the present invention;

[0032] Figure 6 Shown for the examples of the present invention are the carbonation efficiency values ​​at different liquid-to-solid ratios;

[0033] Figure 7 The carbonation efficiency under different liquid-to-solid ratios shown in the examples of the present invention.

[0034] List of Figure Symbols:

[0035] 1. Gas cylinder; 2. First gas flow meter; 3. Second gas flow meter; 4. Third gas flow meter; 5. Gas mixer; 6. First pressure sensor; 7. Second pressure sensor; 8. Valve; 9. Second reaction slurry outlet; 10. Third pressure sensor; 11. Solid-liquid phase feed port; 12. Touch screen controller; 13. Desiccant; 14. Fourth gas flow meter; 15. CO2 sensor; 16 First pH meter; 17. First conductivity probe; 18. Bubbling bed reactor; 19. Second pH meter; 20. Second conductivity probe; 21, 22, 25. Pump; 23. Cleaning water inlet; 24. Air distribution plate; 26. First reaction slurry outlet; 27. Gas inlet; 28. Computer. DETAILED DESCRIPTION

[0036] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0037] A carbide slag direct liquid phase mineralization carbon fixation bubbling bed device and parameter real-time monitoring technology based on the present invention. Solid waste carbide slag is the residue produced by industrial production of polyvinyl chloride resin using calcium carbide. my country's annual production of carbide slag is about 43 million tons, and the current accumulated stockpile of carbide slag has exceeded 100 million tons. The main component of carbide slag is calcium hydroxide. Figure 1The bubbling bed device shown includes a bubbling bed reactor body and a measuring device. The bubbling bed reactor body includes a bubbling bed reactor 18, a solid-liquid phase feed port 11, an air distribution plate 24, a first reaction slurry outlet 26 and a gas phase inlet 27; the collection and analysis system includes a second reaction slurry outlet 9, a first pH meter 16, a second pH meter 18, a first pressure sensor 6, a second pressure sensor 7, a third pressure sensor 10, a CO2 sensor 15, a ruler, a touch screen controller with adjustable parameters 12, a data acquisition card and a computer 28. The bubbling bed reactor body is used for direct liquid phase mineralization and carbon fixation reaction of carbide slag and sampling; the measuring device is used to collect the pressure pulsation signal, pH value, conductivity, bed height and reactor outlet CO2 concentration in the bubbling bed reactor, and is connected to the computer through the data acquisition card and stores the data in the computer.

[0038] By controlling the three important operating parameters of superficial gas velocity, flue gas concentration and liquid-to-solid ratio, a higher gas-liquid-solid three-phase mass transfer rate and mineralization carbon fixation efficiency can be obtained in the device during the reaction.

[0039] The first pH meter, the second pH meter, the first conductivity probe, and the second conductivity probe are arranged on the right side of the bubbling bed reactor, and are used to measure the pH and conductivity values ​​of the reaction slurry obtained by the pump; three pressure sensors (the first pressure sensor, the second pressure sensor, and the third pressure sensor) are arranged on the left side of the bubbling bed reactor, with heights of 3.8 cm, 15.1 cm, and 23.8 cm, respectively, and are used to measure the pressures at different bed heights in the bed; the CO2 sensor is connected to the gas outlet at the top of the bubbling bed reactor, and is used to measure the CO2 concentration of the reactor outlet gas; the touch screen controller with adjustable parameters and the computer are used to control the flow rate and CO2 concentration of the inlet gas and store the data measured during the reaction; the ruler is pasted on the right side of the bubbling bed, and is used to read the bed height before and after the reaction.

[0040] A method for monitoring important parameters during the operation of an alkaline solid waste direct liquid phase mineralization carbon fixation bubbling bed device, the specific steps are as follows:

[0041] (1) Solid and liquid materials of a certain ratio are sequentially added into the bubbling reactor 18 through the solid-liquid phase feed port 11 at the upper portion of the bubbling bed reactor 18, and the CO2 concentration y of the mixed gas of CO2 and N2 passing through the gas inlet 27 is set by the touch screen controller 12. in and volume flow Q in After that, N2 is passed for a period of time. When the pH of the mixed slurry of solid phase and liquid phase is greater than 12.5, it is considered to be mixed evenly. Then, a specified flow rate of CO2 and N2 mixed gas is passed.

[0042] (2) mixing and reacting gas, liquid and solid phases in the bubbling bed reactor 18, collecting the pressure pulsation signal, pH value and CO2 concentration yout at the gas outlet of the slurry in the bubbling bed reactor 18 in real time through the first pH meter 16, the second pH meter 19, the first conductivity probe 17, the second conductivity probe 20, the first pressure sensor 6, the second pressure sensor 7, the third pressure sensor 10 and the CO2 sensor 15. After all the data are collected, they are collected and stored in the computer 28 through the data acquisition card. When the pH of the slurry is lower than 6, the reaction is considered to be completed, and a portion of the slurry is taken out for thermogravimetric analysis after the reaction is completed;

[0043] (3) Performing time-frequency domain analysis on the measured pressure pulsation signal to obtain EMD energy entropy to characterize the flow pattern data and thus determine the flow pattern in the bubbling bed reactor 18; by reading the liquid level before and after the reaction, the gas holdup in the bubbling bed reactor 18 can be obtained as shown in formula (1); at the same time, the bubble size distribution can be obtained by processing the flow image using image pro plus;

[0044]

[0045] Where H represents the bed height after the mixed gas is introduced, m; H0 represents the bed height before the gas is introduced, m; ε g represents the gas holdup in the bubbling bed reactor;

[0046] (4) The mass transfer parameters monitored during the liquid phase mineralization carbon fixation process include: gas phase side mass transfer coefficient k L a and liquid side mass transfer coefficient k G a; The mass transfer coefficient is monitored in real time by the outlet gas CO2 concentration; the calculation formula is shown in formula (2) (3):

[0047]

[0048] Among them, in formula (2) and formula (3), and V represents the molar ratio of CO2 to N2 at the gas inlet and gas outlet of the bubbling bed reactor 18, respectively; L Indicates the volume of liquid phase added, L; P in and P out represents the CO2 partial pressure at the gas inlet and gas outlet of the bubbling bed reactor 18, MPa; H represents the Henry coefficient of CO2 in water at normal temperature and pressure, which is 0.338 mol / (L·Mpa);

[0049] (5) The reaction parameters monitored in the liquid phase mineralization carbon fixation process include pH, conductivity and carbonation efficiency; the time point and pH value of complete precipitation of the carbonation reaction are analyzed by drawing pH and conductivity curves; the carbonation efficiency value is calculated by thermogravimetric analysis and CO2 concentration at the gas inlet and gas outlet, as shown in formula (4)(5);

[0050]

[0051] In formula (4), η is the carbonation efficiency of alkaline solid waste, the original mass is m1, in TG analysis, the mass percentage of Ca(OH)2 in the unreacted solid waste completely decomposed at 300-500℃ is A1, the mass of the product after carbonation reaction is m2, and the mass reduction percentage of Ca(OH)2 in the alkaline solid waste after reaction is defined as A 2。

[0052] In formula (5) is the total amount of CO2 introduced, mol; is the total amount of CO2 in the gas discharged from the gas outlet after the reaction, mol; is the amount of Ca(OH)2 in carbide slag before reaction, mol.

[0053] Example 1

[0054] A bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste, the device comprises a bubbling bed reactor 18 and a measuring device, the bubbling bed reactor 18 body is used for performing direct liquid phase mineralization and carbon fixation reaction of alkaline solid waste; the measuring device is used for collecting pressure pulsation signals, pH value, conductivity and CO2 concentration of reactor outlet gas in the bubbling bed reactor 18.

[0055] A solid-liquid phase feed port 11, a gas outlet and a flow observation window are provided at the upper part of the bubbling bed reactor 18, and the gas outlet is connected to the CO2 sensor 15; an air distribution plate 24, a gas inlet 27 and a first reaction slurry outlet 26 are provided at the bottom of the bubbling bed reactor 18, and the gas inlet 27 is connected to a flow meter through a gas mixer 5, and the first gas flow meter 2, the second gas flow meter 3, and the third gas flow meter 4 are respectively connected to a gas cylinder 1, and the gas enters the gas mixer 5 at a certain flow rate through the gas flow meter from different gas cylinders 1, and finally enters the gas inlet 27; a second reaction slurry outlet 9 and a pressure sensor are provided on one side of the bubbling bed reactor 18, and a sampling port is provided on the other side of the bubbling bed reactor 18.

[0056] The measuring device includes a pH meter, a conductivity probe, a pressure sensor, and a CO2 sensor 15 arranged on the side of the bubbling bed reactor 18; two sampling ports are arranged on the right side of the bubbling bed reactor 18, and the sampling ports are connected to the bubbling bed reactor 18 through a pump. The two sampling ports are respectively provided with a first pH meter 16, a second pH meter 19, a first conductivity probe 17, and a second conductivity probe 20; a first pressure sensor 6, a second pressure sensor 7, and a third pressure sensor 10 are arranged at three different axial positions on the left side of the bubbling bed reactor 18. The bubbling bed device also includes a touch screen controller 12 with adjustable parameters, and all data are stored in a computer 28 via a data acquisition card.

[0057] A fourth gas flow meter 14 and a desiccant 13 are also provided between the CO2 sensor 15 and the gas outlet.

[0058] Example 2

[0059] The device of Example 1 was used as the experimental equipment, carbide slag was used as the alkaline solid waste (solid phase), and deionized water was used as the liquid phase to carry out the direct liquid phase mineralization carbon fixation reaction. The specific operation steps are as follows:

[0060] (1) Weigh 30.00 g of carbide slag and a certain amount of deionized water (determined according to the liquid-solid ratio), add them sequentially from the upper solid-liquid phase feed port 11 of the bubbling bed reactor, and input the CO2 flow rate (2.52 L / min) and N2 flow rate (10.08 L / min) on the touch screen controller 12 with adjustable parameters;

[0061] Among them, the liquid-to-solid ratio is 5, 10, 20, 30, 40, and 50 mL / g.

[0062] (2) First, N2 is passed for 10-30 seconds to make the gas, liquid and solid three phases in the bubbling bed reactor 18 uniformly mixed. When the pH value is greater than 12.5, the mixture is considered uniform;

[0063] (3) A mixed gas of CO2 and N2 with a volume flow rate of 12.6 L / min and a CO2 concentration of 20% was introduced to start the mineralization carbon fixation reaction. After 15-16 minutes, the reaction was considered complete when the pH value dropped to 5.5-6;

[0064] (4) The gas inlet is closed and the experimental bench is cleaned through the touch screen controller 12 with adjustable parameters, and the data of pH value, conductivity, outlet gas CO2 concentration and pressure pulsation are stored in the computer 28.

[0065] The collected data can be used to calculate the flow, mass transfer and reaction parameters of alkaline solid waste carbide slag in the bubbling bed reactor.

[0066] Flow parameters: The measured pressure pulsation signal is analyzed in the time-frequency domain to obtain the EMD energy entropy to characterize the flow pattern data and thus determine the flow pattern in the bubbling bed reactor 18. Figure 2 The energy entropy curves of this example at different liquid-to-solid ratios with gas velocity are shown. In the energy entropy curves, we can clearly see the transition point of the flow pattern, that is, the obvious turning point in the figure (such as Figure 2 By reading the liquid level before and after the reaction, we can get Figure 3 The change curve of the gas holdup in the bubbling bed reactor 18 under different liquid-to-solid ratios (liquid-to-solid ratios of 5, 10, 20, 30, and 40 mL / g) shows that the smaller the liquid-to-solid ratio, the higher the gas holdup.

[0067] Mass transfer parameters: Use the inlet and outlet concentrations of CO2 to calculate the liquid phase mass transfer coefficient k L a and the volumetric mass transfer coefficient k on the gas phase side G a. Such as Figure 4 The curves showing the mass transfer coefficient variation with time at different liquid-to-solid ratios (liquid-to-solid ratios of 5, 10, 20, 30, and 40 mL / g) of this example show that the initial mass transfer coefficient is higher at a lower liquid-to-solid ratio, while the mass transfer coefficient at the end point approaches 0. Figure 5 is k at different liquid-to-solid ratios L a and k G From the value of a, we can see that the changing trend is consistent and the mass transfer is better when the liquid-solid ratio is smaller.

[0068] Reaction parameters: Figure 6 The curves of pH, conductivity and outlet gas CO2 concentration during the reaction process. The main chemical reaction in the reactor can be determined based on different pH values. When the pH is greater than 10, calcium carbonate precipitation occurs, while when the pH is less than 10, CO2 is fixed in the liquid phase. The time point when the precipitation reaction is complete can be determined based on the inflection point of the conductivity. The carbonation efficiency can be calculated using both the solid phase and the gas phase. Figure 7 The figure shows the carbonation efficiency at different liquid-to-solid ratios of this example, which is calculated by the inlet and outlet CO2 concentrations. It can be seen from the figure that the carbonation efficiency is higher at higher and lower liquid-to-solid ratios, and can reach more than 98%.

[0069] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste, characterized in that: The invention comprises a bubbling bed reactor (18) and a measuring device. The upper part of the bubbling bed reactor (18) is provided with a solid-liquid phase feed port (11), a gas outlet and a flow observation window, and the gas outlet is connected to a CO2 sensor (15); the bottom of the bubbling bed reactor (18) is provided with an air distribution plate (24), a gas inlet (27) and a first reaction slurry outlet (26); the gas inlet (27) is connected to a flow meter through a gas mixer (5); the first gas flow meter (2), the second gas flow meter (3) and the third gas flow meter (4) are respectively connected to a gas cylinder (1); one side of the bubbling bed reactor (18) is provided with a second slurry outlet (9) and a pressure sensor; the other side of the bubbling bed reactor (18) is provided with a sampling port and a scale; the measuring device comprises a pH meter, a conductivity probe, a pressure sensor, a CO2 sensor (15), a scale, a touch screen controller (12) with adjustable parameters and a computer (28) arranged on the side of the bubbling bed reactor (18).

2. The bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste according to claim 1, characterized in that: The right side of the bubbling bed reactor (18) is provided with two sampling ports and a scale, the sampling ports are connected to the bubbling bed reactor (18) via a pump, the two sampling ports are respectively provided with a first pH meter (16), a second pH meter (19), a first conductivity probe (17), and a second conductivity probe (20), and the scale is pasted on the right side of the bubbling bed reactor (18); the left side of the bubbling bed reactor (18) is provided with a first pressure sensor (6), a second pressure sensor (7), and a third pressure sensor (10).

3. The bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste according to claim 1, characterized in that: A fourth gas flow meter (14) and a desiccant (13) are also provided between the CO2 sensor (15) and the gas outlet.

4. A method for monitoring important parameters of flow, mass transfer and reaction of direct liquid phase mineralization and carbon fixation of alkaline solid waste, characterized in that: The device for direct liquid phase mineralization and carbon fixation of alkaline solid waste is a bubbling bed device as described in any one of claims 1 to 3, and the parameter detection method comprises the following steps: (1) Solid and liquid materials of a certain ratio are sequentially added into the bubbling bed reactor (18) through the solid and liquid feed port (11) at the upper part of the bubbling bed reactor (18), and the inlet CO2 concentration y of the mixed gas of CO2 and N2 passed through the gas inlet (27) is set by the touch screen controller (12). in and volume flow rate Q in After that, N2 is passed for a period of time. When the pH of the mixed slurry of solid phase and liquid phase is greater than 12.5, it is considered to be mixed evenly. Then, a specified flow rate of CO2 and N2 mixed gas is passed. (2) Mixing and reacting gas, liquid and solid phases in a bubbling bed reactor (18) is performed, and the pressure pulsation signal, pH value, conductivity value and CO2 concentration y at the gas outlet of the slurry in the bubbling bed reactor (18) are collected in real time by using a first pH meter (16), a second pH meter (19), a first conductivity probe (17), a second conductivity probe (20), a first pressure sensor (6), a second pressure sensor (7), a third pressure sensor (10) and a CO2 sensor (15). out After all data are collected, they are collected and stored in a computer (28) via a data acquisition card. When the pH of the slurry is lower than 6, the reaction is considered to be complete. After the reaction is complete, a portion of the slurry is taken out for thermogravimetric analysis. (3) Perform time-frequency domain analysis on the measured pressure pulsation signal to obtain EMD energy entropy to characterize the flow pattern data and then determine the flow pattern in the bubbling bed reactor; by reading the liquid level before and after the reaction, the gas holdup in the bubbling bed can be obtained as shown in formula (1); at the same time, the bubble size distribution can be obtained by processing the flow image through image pro plus; Where H represents the bed height after the mixed gas is introduced, m; H0 represents the bed height before the gas is introduced, m; ε g Represents the gas holdup in the bubbling bed.

5. The parameter monitoring method of the bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste according to claim 4 is characterized in that: The mass transfer parameters monitored in the liquid phase mineralization carbon fixation process include: gas phase side mass transfer coefficient k L a and liquid side mass transfer coefficient k G a; The mass transfer coefficient is monitored in real time by the outlet gas CO2 concentration; the calculation formula is shown in formula (2) (3): Among them, in formula (2) and formula (3), and represents the molar ratio of CO2 to N2 at the gas inlet and gas outlet of the bubbling bed reactor respectively; V L Indicates the volume of liquid phase added, L; P in and P out Respectively represent the CO2 partial pressure at the gas inlet and gas outlet of the bubbling bed reactor, MPa; H represents the Henry coefficient of CO2 in water at room temperature and pressure, which is 0.338 mol / (L·Mpa).

6. The parameter monitoring method of the bubbling bed device for direct liquid phase mineralization and carbon fixation of alkaline solid waste according to claim 4 is characterized in that: The reaction parameters monitored in the liquid phase mineralization carbon fixation process include pH, conductivity and carbonation efficiency; the time point and pH value of complete precipitation of the carbonation reaction are analyzed by drawing the conductivity and pH change curve; the value of carbonation efficiency is calculated by thermogravimetric analysis and CO2 concentration at the gas inlet and gas outlet, as shown in equations (4) and (5); In formula (4), η is the carbonation efficiency of alkaline solid waste, the original mass is m1, in TG analysis, the mass percentage of Ca(OH)2 in the unreacted solid waste completely decomposed at 300-500℃ is A1, the mass of the product after carbonation reaction is m2, and the mass reduction percentage of Ca(OH)2 in the alkaline solid waste after reaction is defined as A 2。 In formula (5) is the total amount of CO2 introduced, mol; is the total amount of CO2 in the gas discharged from the gas outlet after the reaction, mol; is the amount of Ca(OH)2 in the alkaline solid waste before the reaction, mol.

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