A method and system for utilizing metallurgical solid waste to dispose of CO2 in flue gas

Abstract

The application relates to the field of solid waste resource utilization, in particular to a method and system for utilizing metallurgical solid waste to consume CO2 in flue gas; the method comprises the following steps: crushing metallurgical solid waste, and then grinding to a preset particle size to obtain metallurgical solid waste powder; pretreating industrial furnace flue gas to a preset gas concentration to obtain CO2 flue gas; conveying the metallurgical solid waste powder into a consumption container, introducing the CO2 flue gas with a preset flue gas pressure and a preset flue gas flow into the consumption container, then spraying water into the consumption container, and circulating the consumption reaction to a preset solid waste content to obtain solid waste with stable physical properties and flue gas; performing dust removal treatment on the flue gas to obtain exhaust gas; wherein the mass ratio of water to metallurgical solid waste powder is greater than or equal to 5%; through the above method, the acid CO2 gas in the flue gas and the alkaline oxide CaO or MgO substance in the solid waste are fully reacted, the physical and chemical properties of the active substance in the solid waste are stabilized, the CO2 in the flue gas is effectively consumed by the metallurgical solid waste, and the solid waste with stable physical and chemical properties and clean flue gas are obtained.

Description

Technical Field

[0001] This application relates to the field of solid waste resource utilization, and in particular to a method and system for utilizing metallurgical solid waste to dispose of CO2 in flue gas. Background Technology

[0002] Steel smelting consumes vast amounts of resources and energy, while also emitting significant amounts of CO2. Currently, the steel industry primarily utilizes blast furnace-converter processes, accounting for 90% of its production. If we calculate based on 2 tons of CO2 emissions per ton of steel, the steel industry's CO2 emissions exceeded 1.8 billion tons in 2021, accounting for 16% of the national total. This demonstrates that the steel industry is the largest carbon emitter among manufacturing sectors. CO2 in steel production mainly originates from the combustion or reduction of carbon elements in coal and coke. While a small amount of this carbon enters steel materials as alloying elements, the majority remains in the flue gas of various industrial furnaces and kilns. This results in numerous and large sources of CO2 emissions from steel enterprises. Furthermore, due to the low efficiency and high cost of CO2 capture, steel enterprises currently primarily release CO2 into the atmosphere through flue gas emissions.

[0003] Metallurgical solid waste is a solid waste generated during steel production. Statistics show that approximately 200-400 kg of metallurgical solid waste is produced for every ton of steel produced. This waste contains large amounts of unreacted alkaline oxides, calcium oxide (CaO) and magnesium oxide (MgO), which are unstable and react with water (CaO + H₂O = Ca(OH)₂, MgO + H₂O = Mg(OH)₂). During this reaction, their volumes expand by over 90% and 100% respectively, causing cracks in road infrastructure and buildings constructed using this waste, leading to secondary damage and serious safety issues. Therefore, the actual utilization rate of metallurgical solid waste is currently very low. Steel companies mostly dispose of it by stockpiling, which wastes resources, occupies large amounts of arable land, and causes environmental pollution. Since calcium oxide and magnesium oxide are the main factors that disrupt the structure of the solid waste, stabilizing it is crucial for its resource utilization.

[0004] Currently, the main problems with utilizing metallurgical solid waste to dispose of CO2 are complex processes and the high temperature of metallurgical solid waste, which makes it difficult to dispose of CO2. Therefore, how to provide a method for effectively disposing of CO2 in flue gas using metallurgical solid waste, so as to obtain both physicochemically stable solid waste and clean flue gas, is an urgent problem to be solved. Summary of the Invention

[0005] This application provides a method and system for utilizing metallurgical solid waste to eliminate CO2 in flue gas, thereby solving the technical problem in the prior art that it is difficult to obtain physicochemically stable solid waste and clean flue gas by effectively eliminating CO2 in flue gas using metallurgical solid waste.

[0006] In a first aspect, this application provides a method for utilizing metallurgical solid waste to dispose of CO2 in flue gas, the method comprising:

[0007] Metallurgical solid waste is crushed and then ground to a preset particle size to obtain metallurgical solid waste powder.

[0008] Pre-treat industrial furnace flue gas to a preset gas concentration to obtain CO2 flue gas;

[0009] The metallurgical solid waste powder is fed into the disposal container, and CO2 flue gas with a preset flue gas pressure and preset flue gas flow rate is introduced into the disposal container. Then, water is sprayed into the disposal container and the circulation disposal reaction is carried out until the preset solid waste content is reached, so as to obtain solid waste and flue gas with stable physical properties.

[0010] The flue gas is subjected to dust removal treatment to obtain exhaust gas;

[0011] The mass ratio of the water to the metallurgical solid waste powder is ≥5%.

[0012] Optionally, the preset particle size includes a content of metallurgical solid waste powder with a diameter of <1mm >80%.

[0013] Optionally, the preset gas concentration includes a preset SO2 concentration and a preset NO concentration. X Concentration, the preset SO2 concentration is 35 mg / m³ 3 The following refers to the preset NO. X Concentration at 50 mg / m 3 the following.

[0014] Optionally, the preset flue gas pressure is >0.3MPa, and the preset flue gas flow rate is 2m³ / h. 3 / s~100m 3 / s.

[0015] Optionally, the sum of the proportions of calcium oxide and magnesium oxide in the preset solid waste content is less than 2%.

[0016] Optionally, the dust removal treatment includes electrostatic dust removal and / or baghouse dust removal; and / or,

[0017] The dust content of the exhaust gas is <5mg / m³ 3 .

[0018] Optionally, the industrial furnace flue gas includes at least one of coking oven flue gas, lime kiln flue gas, rotary kiln flue gas, hot blast stove flue gas, steel rolling heating furnace flue gas, and gas-fired boiler flue gas.

[0019] Optionally, the metallurgical solid waste includes at least one of blast furnace slag, converter slag, electric arc furnace slag, refining slag, desulfurization ash, and metallurgical dust and sludge.

[0020] Secondly, this application provides a system for utilizing metallurgical solid waste to dispose of CO2 in flue gas, the system being adapted to the method described in the first aspect, the system comprising:

[0021] A disposal unit, comprising a sprayer and a disposal tower, wherein the sprayer is located at the top of the disposal tower;

[0022] The flue gas treatment unit includes a pre-processor and a booster fan. One end of the booster fan is connected to the air inlet of the absorption tower, and the other end of the booster fan is connected to the air outlet of the pre-processor, so as to realize the pre-treatment of industrial furnace flue gas.

[0023] A metallurgical solid waste treatment unit, comprising a crusher, a grinding mill, and a solid waste storage silo, wherein one end of the solid waste storage silo is connected to the disposal tower, the other end of the solid waste storage silo is connected to the grinding mill, and the crusher is connected to the grinding mill;

[0024] Water tank, the water tank being connected to the sprayer;

[0025] The grinding mill is also connected to the discharge end of the digestion tower to utilize metallurgical solid waste for recycling and digestion.

[0026] Optionally, the system further includes:

[0027] The exhaust gas treatment unit includes a dust suppression device and a chimney. One end of the dust suppression device is connected to the outlet of the dust collection tower, and the other end of the dust suppression device is connected to the inlet of the chimney.

[0028] The technical solutions provided in this application have the following advantages compared with the prior art:

[0029] This application provides a method for utilizing metallurgical solid waste to eliminate CO2 from flue gas. The method involves pre-treating the metallurgical solid waste using crushing and grinding processes, followed by pre-treatment of industrial furnace flue gas. The pre-treated flue gas is then pressurized and injected, forming a fluidized state. Combined with sprayed water and input metallurgical solid waste powder, the fluidized state leverages the large contact area and high reaction efficiency between solids and gases to fully react the acidic CO2 gas in the flue gas with the alkaline oxides CaO or MgO in the solid waste, generating CaCO3 salts or MgCO3 salts. This stabilizes the physicochemical properties of the active substances in the solid waste, thus achieving simultaneous treatment of metallurgical solid waste and elimination of CO2 from flue gas. Ultimately, this method effectively eliminates CO2 from flue gas using metallurgical solid waste, resulting in physicochemically stable solid waste and clean flue gas. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic flowchart illustrating a method for utilizing metallurgical solid waste to dispose of CO2 in flue gas, provided in an embodiment of this application;

[0033] Figure 2 A detailed flowchart illustrating a method for utilizing metallurgical solid waste to dispose of CO2 in flue gas, provided as an embodiment of this application;

[0034] Figure 3 A schematic diagram of the logical structure of a system for utilizing metallurgical solid waste to dispose of CO2 in flue gas, provided in an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of the actual structure of a system for utilizing metallurgical solid waste to dispose of CO2 in flue gas, provided in an embodiment of this application.

[0036] Among them, 1-disposal unit, 11-sprayer, 12-disposal tower, 2-flue gas treatment unit, 21-pre-processor, 22-booster fan, 3-metallurgical solid waste treatment unit, 31-crusher, 32-grinding mill, 33-solid waste storage silo, 4-water tank, 5-tail gas treatment unit, 51-dust suppression device, 52-chimney. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0038] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0039] The creative thinking behind this application is:

[0040] Currently, there are only a few technologies related to CO2 capture and metallurgical slag treatment in steel enterprises. For example, there is the use of low-temperature waste heat power generation systems for dry CO2 capture of sintering waste gas in steel plants. These systems utilize alkali metal carbonates to capture CO2, which requires two processes: capture and regeneration. The process is complex and costly, and requires the use of large amounts of alkali metal carbonates such as NaCO3. Another example is the comprehensive utilization method of metallurgical solid waste, which requires the metallurgical slag to be in a high-temperature molten state. This high-temperature molten state requires a temperature of 1400℃, so the molten slag must contain a large amount of sensible heat, which cannot absorb CO2.

[0041] like Figure 1 and Figure 2 As shown in the embodiment of this application, a method for utilizing metallurgical solid waste to dispose of CO2 in flue gas is provided, the method comprising:

[0042] S1. Crushing metallurgical solid waste and then grinding it to a preset particle size to obtain metallurgical solid waste powder;

[0043] S2. Pre-treat industrial furnace flue gas to a preset gas concentration to obtain CO2 flue gas;

[0044] S3. The metallurgical solid waste powder is conveyed into the disposal container, and CO2 flue gas with a preset flue gas pressure and preset flue gas flow rate is introduced into the disposal container. Then, water is sprayed into the disposal container and the circulation disposal reaction is carried out until the preset solid waste content is reached, so as to obtain solid waste and flue gas with stable physical properties.

[0045] S4. The flue gas is subjected to dust removal treatment to obtain exhaust gas;

[0046] The mass ratio of the water to the metallurgical solid waste powder is ≥5%.

[0047] In this embodiment, considering that CaO and MgO react with CO2 very slowly in dry conditions, but in a humid environment, CaO first reacts with H2O to form Ca(OH)2, and then reacts with CO2 to form CaCO3, the reaction rate will be greatly increased. Therefore, limiting the specific mass ratio between water and metallurgical solid waste powder can ensure that the alkaline oxides CaO and MgO in the metallurgical solid waste first react with water to form hydroxides, and then react fully with CO2 in the flue gas to obtain CaCO3 and MgCO3 products, thereby completing the elimination of CO2 in the flue gas.

[0048] The digestion reaction specifically includes the following reactions:

[0049] CaO + H₂O = Ca(OH)₂

[0050] Ca(OH)₂ + CO₂ = CaCO₃ + H₂O

[0051] MgO + H₂O = Mg(OH)₂

[0052] Mg(OH)₂ + CO₂ = MgCO₃ + H₂O

[0053] The overall reaction formula is:

[0054] CaO + H₂O + CO₂ = CaCO₃ + H₂O

[0055] MgO + H₂O + CO₂ = MgCO₃ + H₂O.

[0056] In some optional embodiments, the preset particle size includes a content of metallurgical solid waste powder with a diameter of <1 mm >80%.

[0057] In this embodiment of the application, the positive effect of limiting the specific preset particle size is to ensure that the particle size of the metallurgical solid waste powder is small enough so that the alkaline oxides in the metallurgical solid waste powder can fully react with CO2 in the flue gas in the water environment.

[0058] In some optional embodiments, the preset gas concentration includes a preset SO2 concentration and a preset NO concentration. X Concentration, the preset SO2 concentration is 35 mg / m³ 3 The following refers to the preset NO. X Concentration at 50 mg / m 3 the following.

[0059] In this embodiment, the specific SO2 and NO concentrations in the preset gas concentration are defined. X Concentration can avoid SO2 and NO X It reacts with alkaline oxides, thus consuming them and affecting the reaction between alkaline oxides and CO2 in flue gas, thereby affecting the CO2 absorption in flue gas and the treatment effect of metallurgical solid waste.

[0060] In some optional embodiments, the preset flue gas pressure is >0.3MPa, and the preset flue gas flow rate is 2m³ / h. 3 / s~100m 3 / s.

[0061] In this embodiment, the specific preset flue gas pressure and preset flue gas flow rate are defined to ensure sufficient contact between CO2 in the flue gas and metallurgical solid waste powder, so that with the support of water, CO2 in the flue gas can fully react and be completely absorbed.

[0062] In some optional embodiments, the sum of the proportions of calcium oxide and magnesium oxide in the preset solid waste content is less than 2%.

[0063] In this embodiment of the application, the specific proportions of calcium oxide and magnesium oxide in the preset solid waste content are limited to ensure that the alkaline oxides in the metallurgical solid waste powder are completely consumed, thereby obtaining a solid waste product with stable physical properties, and realizing the treatment of metallurgical solid waste while absorbing CO2 in flue gas.

[0064] In some optional embodiments, the dust removal process includes electrostatic dust removal and / or baghouse dust removal; and / or,

[0065] The dust content of the exhaust gas is <5mg / m³ 3 .

[0066] In this embodiment of the application, the specific method of dust removal treatment is defined to ensure that the impurities and dust in the flue gas that has undergone the absorption reaction are completely absorbed, thereby obtaining pure emission gas.

[0067] The dust content in the emission gas is limited to <5mg / m³. 3 The positive effect is that within the range of dust content, it can ensure that the emission gas is within the low emission requirements, thereby ensuring the treatment effect of flue gas.

[0068] In some alternative embodiments, the industrial furnace flue gas includes at least one of coke oven flue gas, lime kiln flue gas, rotary kiln flue gas, hot blast stove flue gas, steel rolling heating furnace flue gas, and gas-fired boiler flue gas.

[0069] In this embodiment of the application, the source of industrial furnace flue gas is limited, which can encompass most steelmaking processes that produce CO2 gas, thereby ensuring the universality of this application.

[0070] In some alternative embodiments, the metallurgical solid waste includes at least one of blast furnace slag, converter slag, electric arc furnace slag, refining slag, desulfurization ash, and metallurgical dust and sludge.

[0071] In this application embodiment, the specific source of metallurgical solid waste is defined, which can encompass most of the waste slag containing alkaline oxides generated in steelmaking processes, thereby ensuring the universality of this application.

[0072] Based on a general inventive concept, such as Figure 3 and Figure 4 As shown, this application provides a system for utilizing metallurgical solid waste to dispose of CO2 in flue gas. The system is adapted to the method described above and includes:

[0073] The disposal unit 1 includes a sprayer 11 and a disposal tower 12, wherein the sprayer 11 is located at the top of the disposal tower 12;

[0074] The flue gas treatment unit 2 includes a pre-processor 21 and a booster fan 22. One end of the booster fan 22 is connected to the air inlet of the absorption tower 12, and the other end of the booster fan 22 is connected to the air outlet of the pre-processor 21, so as to realize the pre-treatment of industrial furnace flue gas.

[0075] Metallurgical solid waste treatment unit 3, which includes a crusher 31, a grinding mill 32 and a solid waste storage silo 33. One end of the solid waste storage silo 33 is connected to the disposal tower 12, and the other end of the solid waste storage silo 33 is connected to the grinding mill 32. The crusher 31 is connected to the grinding mill 32.

[0076] Water tank 4, which is connected to the sprayer 11;

[0077] The grinding mill 32 is also connected to the discharge end of the digestion tower 12 to utilize metallurgical solid waste for recycling and digestion.

[0078] In this embodiment of the application, by designing a system including a disposal unit 1, a flue gas treatment unit 2, and a metallurgical solid waste treatment unit 3, the flue gas treatment unit 2 can be used to pre-treat industrial furnace flue gas, thereby obtaining flue gas with low SO2 and NOx content. At the same time, water is sprayed into the disposal unit 1 through a water tank 4, and then metallurgical solid waste powder is obtained through the metallurgical solid waste treatment unit 3. Thus, the treatment of metallurgical solid waste and the disposal of CO2 in the flue gas are completed in the disposal tower 12 of the disposal unit 1.

[0079] The system is implemented based on the above method. The specific steps of the method can be referred to the above embodiments. Since the system adopts some or all of the technical solutions of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated here.

[0080] In some alternative implementations, the system further includes:

[0081] The exhaust gas treatment unit 5 includes a dust suppression device 51 and a chimney 52. ​​One end of the dust suppression device 51 is connected to the outlet of the dust collection tower 12, and the other end of the dust suppression device 51 is connected to the inlet of the chimney 52.

[0082] In this embodiment of the application, by introducing the exhaust gas treatment unit 5 into the system, it can be ensured that the dust content in the exhaust gas is below 5mg / m3, thereby achieving the low emission requirements and ensuring the treatment effect of the flue gas.

[0083] The present application is further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards. If there is no corresponding national standard, then general international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0084] Example 1

[0085] like Figure 1 As shown, a type of tailings from the steel refining process (hereinafter referred to as tailings) was selected. The chemical composition of the tailings, by percentage, is: CaO: 44%, Fe2O3: 22%, SiO2: 19%, Al2O3: 8%, MgO: 5%, MnO: 2%. After being crushed by a roller press, the coarse tailings still have a relatively large particle size, with an average diameter of approximately 5 mm. After further grinding by a ball mill, the average particle size reaches 0.8 mm, and particles smaller than 0.5 mm account for 86%.

[0086] The pulverized tailings are transported to the solid waste storage silo 33 for storage. Subsequently, the tailings are fed into the collection area of ​​the digester 12 through the four feed ports at the bottom of the digester 12 via a motor-driven conveyor belt, and are evenly distributed.

[0087] The flue gas after combustion in the steel rolling furnace (average concentration of each component: SO2: 2566 mg / m³) 3 NO X 411mg / m 3 CO2: 1938 mg / m³ 3 After being piped into the counter-current activated carbon desulfurization and denitrification equipment, SO2 and NO are simultaneously removed. X After being reduced to a low level, the SO2 content, as detected by flue gas analysis, was approximately 18 mg / m³. 3 NO X The content is approximately 34 mg / m³ 3 The flue gas pressure is 0.11 MPa.

[0088] Removal of SO2 and NO X The flue gas is then fed into the Roots blower through a pipeline. The flue gas pressure reaches 0.35 MPa, and the flue gas is blown into the bottom of the collection zone of the scavenging tower 12 through the flue gas inlet valve.

[0089] After the flue gas is blown in, the sprayer located at the top of the 12th tower rotates and sprays H2O at a flow rate of 0.5 kg / s.

[0090] After the reaction has been completed for 120 seconds, the flue gas is stopped being blown in, and the collector collects the tailings at the bottom of the gas into the hopper.

[0091] The tailings in the hopper were sampled, and chemical testing showed that the mass contents of CaO and MgO were 0.11% and 0.3% respectively, which met the requirements. The samples were then transported by material truck to the solid waste storage warehouse.

[0092] The average CO2 concentration in the flue gas was measured to be 427 mg / m³. 3 The dust concentration decreased by approximately 77% compared to before disposal, with the dust content after treatment by the dust collector being 3.2 mg / m³. 3 It meets the requirements for ultra-low emissions and is emitted into the atmosphere through chimney 52.

[0093] Example 2

[0094] Comparing Example 2 with Example 1, the difference between Example 2 and Example 1 is as follows:

[0095] A type of desulfurization ash from a steel plant was selected. The chemical composition of this desulfurization ash, by percentage, is: SiO2: 30%, Al2O3: 7%, CaO: 28%, SO3: 16%, CaSO3: 15%, CaSO4: 3%. The agglomerated desulfurization ash was fed into a jaw crusher 31 to be crushed into smaller pieces, and then conveyed to a ball mill for grinding. After grinding, the average particle size of the desulfurization ash was measured, with 82% having a particle size less than 1 mm and 14% having a particle size greater than 1 mm. A screening machine returned desulfurization ash particles larger than 1 mm to the ball mill, while desulfurization ash smaller than 1 mm was poured into a solid waste storage silo 33.

[0096] Flue gas from gas-fired boiler (average concentration of SO2: 1881 mg / m³) 3 NO X 473mg / m 3 CO2: 1420 mg / m³ 3 After passing through the dense phase dry tower desulfurization and SCR denitrification equipment group, the SO2 content was measured to be 16 mg / m³. 3 NO X The content is 27 mg / m 3 After desulfurization and denitrification, the flue gas is fed into the mechanical booster fan 22 through the pipeline. The outlet pressure increases to 0.39 MPa. The flue gas valve of the digester 12 is opened, and the flue gas is blown upward from the bottom of the digester 12.

[0097] Meanwhile, the desulfurization ash is fed into the collection tower 12 from the conveying valve near the bottom. Under the scouring of the high-pressure flue gas, the flue gas flows at high speed in the tower. Atomized H2O is sprayed into the spray nozzle located on the side wall of the collection tower at a flow rate of 0.2 kg / s. The H2O, flue gas and desulfurization ash are fully mixed and reacted under the impact of the airflow.

[0098] After 100 seconds of flue gas injection, the injection is stopped. Once the desulfurization ash particles have settled, the slag remover at the bottom of the disposal tower 12 collects the reacted desulfurization ash in a hopper. Samples of the reacted desulfurization ash are taken and analyzed using spectroscopic chemical composition analysis. The results show a CaO content of 0.7% and no MgO, with a combined mass percentage of 0.7%, meeting the stability assessment requirements for desulfurization ash. The ash is then transported by material truck to a solid waste storage warehouse for future use as roadbed material.

[0099] The average CO2 concentration in the flue gas was measured to be 644 mg / m³. 3 The dust concentration decreased by approximately 54% compared to before disposal, with the dust content after treatment by the dust collector being 1.9 mg / m³. 3 It meets the requirements for ultra-low emissions and is emitted into the atmosphere through chimney 52.

[0100] One or more technical solutions in the embodiments of this application have at least the following technical effects or advantages:

[0101] (1) The method for utilizing metallurgical solid waste to dispose of CO2 in flue gas provided in the embodiments of this application can simultaneously complete CO2 disposal and solid waste resource utilization treatment. It can reduce the CO2 concentration in flue gas of various industrial furnaces and kilns in steel enterprises, reduce the total CO2 emissions of enterprises, and improve the resource utilization rate and added value of metallurgical solid waste.

[0102] (2) The method for disposing of CO2 in flue gas by metallurgical solid waste provided in this application uses two low-value wastes (solid waste and waste gas) from steel enterprises to carry out the two processes of metallurgical solid waste treatment and CO2 disposal simultaneously. This not only improves the resource utilization rate and added value of metallurgical solid waste, but also reduces the CO2 concentration in flue gas of various industrial furnaces and kilns in steel enterprises, thereby reducing the CO2 emission intensity and total amount of steel enterprises.

[0103] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0104] In this application, unless otherwise stated, directional terms such as "upper" and "lower" specifically refer to the drawing directions in the accompanying drawings. Furthermore, in the description of this application, terms such as "comprising" and "including" mean "including but not limited to." In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this document, "and / or" describes the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this document, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" or "at least one of a, b, and c" can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be a single or multiple.

[0105] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for utilizing metallurgical solid waste to dispose of CO2 in flue gas, characterized in that, The method includes: Metallurgical solid waste is crushed and then ground to a preset particle size to obtain metallurgical solid waste powder. Pre-treat industrial furnace flue gas to a preset gas concentration to obtain CO2 flue gas; The metallurgical solid waste powder is fed into the disposal container, and CO2 flue gas with a preset flue gas pressure and preset flue gas flow rate is introduced into the disposal container. Then, water is sprayed into the disposal container in the form of atomization, so that the mass ratio of water to metallurgical solid waste powder is ≥5%, so that the metallurgical solid waste powder is in a moist state, and the disposal reaction is carried out in a cycle until the preset solid waste content is reached, so as to obtain solid waste and flue gas with stable physical properties. The flue gas is subjected to dust removal treatment to obtain exhaust gas; Wherein, the preset gas concentration includes a preset SO2 concentration and a preset NO X concentration, the preset SO2 concentration being 35mg / m 3 3 or less, and the preset NO X concentration being 50mg / m 3 3 or less. The sum of the proportions of calcium oxide and magnesium oxide in the preset solid waste content is <2%; The preset particle size includes metallurgical solid waste powder with a diameter <1mm containing >80%; The preset flue gas pressure is >0.3MPa, and the preset flue gas flow rate is 2m³ / h. 3 / s~100m 3 / s; the dust content of the emitted gas is <5mg / m³ 3 .

2. The method according to claim 1, characterized in that, The dust removal process includes electrostatic dust removal and / or bag filter dust removal.

3. The method according to claim 1, characterized in that, The industrial furnace flue gas includes at least one of the following: coke oven flue gas, lime kiln flue gas, rotary kiln flue gas, hot blast stove flue gas, steel rolling heating furnace flue gas, and gas-fired boiler flue gas.

4. The method according to claim 1, characterized in that, The metallurgical solid waste includes at least one of blast furnace slag, converter slag, electric arc furnace slag, refining slag, desulfurization ash, and metallurgical dust and sludge.

5. A system for utilizing metallurgical solid waste to dispose of CO2 in flue gas, characterized in that, The system is adapted to the method as described in any one of claims 1-4, the system comprising: The disposal unit (1) includes a sprayer (11) and a disposal tower (12), wherein the sprayer (11) is located at the top of the disposal tower (12); The flue gas treatment unit (2) includes a pre-processor (21) and a booster fan (22). One end of the booster fan (22) is connected to the air inlet of the absorption tower (12), and the other end of the booster fan (22) is connected to the air outlet of the pre-processor (21) to achieve pre-treatment of industrial furnace flue gas. Metallurgical solid waste treatment unit (3), the metallurgical solid waste treatment unit (3) includes a crusher (31), a grinding mill (32) and a solid waste storage silo (33), one end of the solid waste storage silo (33) is connected to the disposal tower (12), the other end of the solid waste storage silo (33) is connected to the grinding mill (32), and the crusher (31) is connected to the grinding mill (32); Water tank (4), the water tank (4) being connected to the sprayer (11); The grinding mill (32) is also connected to the discharge end of the digestion tower (12) to utilize metallurgical solid waste for recycling and digestion.

6. The system according to claim 5, characterized in that, The system also includes: The exhaust gas treatment unit (5) includes a dust suppression device (51) and a chimney (52). One end of the dust suppression device (51) is connected to the outlet of the dust collection tower (12), and the other end of the dust suppression device (51) is connected to the inlet of the chimney (52).

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