Dense-phase steel slag carbonization device

Abstract

The dense-phase steel slag carbonization device comprises a bucket elevator, a dense-phase carbonization tower, a spraying device, an intermediate bin, a finished product bin and a monitoring module, flue gas containing carbon dioxide enters the reaction cavity from a flue gas inlet of the dense-phase carbonization tower; the bucket elevator is used for conveying steel slag powder into the dense-phase carbonization tower from the first conveying equipment; the spraying device is used for spraying water and additives into the reaction cavity of the dense-phase carbonization tower; the intermediate bin is used for screening and collecting the steel slag output along with the flue gas; the reaction cavity is used for enabling the steel slag, water and carbon dioxide entering the dense-phase carbonization tower to be subjected to a three-phase carbonization reaction; flue gas after reaction is discharged from a flue gas outlet; the reacted carbonized steel slag is discharged along with the flue gas and then enters an intermediate bin; the monitoring module is used for monitoring the water content and the carbon dioxide concentration of the steel slag in the dense-phase carbonization tower and adjusting the adding amount of water, additives and / or steel slag powder in real time according to the water content and the carbon dioxide concentration; the finished product bin is used for collecting carbonized steel slag from the ash bucket and the intermediate bin. The large-scale continuous steel slag carbonization reaction is realized, and the efficient recycling of the steel slag is realized.

Description

Technical Field

[0001] The invention relates to the technical field of industrial waste treatment, in particular to a dense phase steel slag carbonization device. Background Art

[0002] China's annual crude steel output will be about 1 billion tons in 2023, accounting for more than 50% of the world's total. Steel slag, as a by-product of the steelmaking process, accounts for about 15% to 20% of crude steel emissions.

[0004] The Ca content in steel slag is about 40%, which can be used to replace cement and natural aggregate in concrete. The Ca in steel slag exists in the form of free calcium oxide and calcium silicate, and reacts with CO2 to form CaCO3. The dissolution of free calcium oxide is conducive to the stabilization of steel slag and the improvement of its utilization performance. Therefore, steel slag carbonization technology can not only solidify a large amount of CO2, but also realize the effective utilization of secondary resources. The bricks, tiles and other building materials prepared from it have the advantages of high strength, low price and good stability.

[0005] The current steel slag carbonization technology mainly involves a carbonization method in which the steel slag is made into bricks and then placed in a CO2 curing box (CN111763786A, CN116514476A, CN113955999A). On the one hand, it has defects such as long reaction time, poor carbon fixation ability, complex carbonization process, and high requirements for temperature and atmosphere. On the other hand, the formed brick products are not suitable for scenes such as road and underground mine filling, which limits the widespread use of carbonized steel slag. Summary of the invention

[0006] In view of this, the embodiments of the present application provide a dense phase steel slag carbonization device to solve at least one problem existing in the background technology, so as to achieve efficient steel slag powder carbonization and realize large-scale continuous steel slag carbonization reaction.

[0007] In a first aspect, an embodiment of the present application provides a dense phase steel slag carbonization device, comprising:

[0008] Bucket elevator, dense phase carbonization tower, spray device, intermediate bin, finished product bin and monitoring module;

[0009] The dense phase carbonization tower comprises a flue gas inlet, a reaction chamber, a flue gas outlet and an ash hopper; flue gas containing carbon dioxide enters the reaction chamber from the flue gas inlet;

[0010] The bucket elevator is used to transport the steel slag powder from the first conveying device into the dense phase carbonization tower;

[0011] The spraying device is used to spray water and additives into the reaction chamber of the dense phase carbonization tower;

[0012] The intermediate bin is arranged between the smoke outlet and the finished product bin, and is used to screen and collect the steel slag output along with the smoke;

[0013] The reaction chamber is used to cause the steel slag, water and carbon dioxide entering the dense phase carbonization tower to undergo a three-phase carbonization reaction; the flue gas after the reaction is discharged from the flue gas outlet; the carbonized steel slag after the reaction is discharged along with the flue gas and enters the intermediate bin;

[0014] The monitoring module is used to monitor the water content and carbon dioxide concentration of the steel slag in the dense phase carbonization tower, and to adjust the addition amount of the water, the additive and / or the steel slag powder in real time according to the water content and the carbon dioxide concentration;

[0015] The finished product bin is used to collect carbonized steel slag from the ash hopper and the intermediate bin.

[0016] In combination with the first aspect of the present application, in an optional embodiment, the dense phase carbonization tower includes a rectification zone, a main reaction zone, a dynamic adjustment zone, and a reaction adjustment zone; a guide plate is provided in the rectification zone to ensure that the flow field is uniform and stable when the flue gas and materials pass through the guide plate; the main reaction zone is used to complete most of the carbonization reaction; the dynamic adjustment zone is used to monitor and optimize the amount of reactant addition; in the reaction adjustment zone, the monitoring module automatically adjusts the amount of reactant addition according to the calculated amount of material addition.

[0017] In combination with the first aspect of the present application, in an optional implementation manner, injection ports of the spray device are respectively arranged at the top, middle and bottom of the reaction chamber.

[0018] In combination with the first aspect of the present application, in an optional embodiment, it also includes a dust collector, which is connected to the intermediate bin and is used to remove dust from the flue gas discharged from the intermediate bin and discharge clean flue gas.

[0019] In combination with the first aspect of the present application, in an optional embodiment, it also includes a chimney, which is connected to the dust collector through a fan and is used to discharge the smoke after dust removal.

[0020] In combination with the first aspect of the present application, in an optional embodiment, it also includes a flexible stirring device, which is arranged in the reaction chamber and is used to make the water, the additive and / or the steel slag powder react fully.

[0021] In combination with the first aspect of the present application, in an optional embodiment, it also includes a fluidizing device connected between the chimney and the ash hopper at the bottom of the dense phase carbonization tower, which is used to make part of the flue gas discharged from the chimney flow back to the ash hopper.

[0022] In combination with the first aspect of the present application, in an optional embodiment, the first conveying equipment is arranged below the dense phase carbonization tower, and is used to convey the steel slag powder discharged from the ash hopper at the bottom of the dense phase carbonization tower to the bucket elevator again.

[0023] In combination with the first aspect of the present application, in an optional embodiment, a second conveying device is provided below the dust collector for conveying the carbonized steel slag collected by the dust collector to the finished product bin.

[0024] In combination with the first aspect of the present application, in an optional embodiment, the monitoring module is respectively connected to a flow meter, a regulating valve, a water pump and a bucket elevator control device, and is used to control the water output of the spraying device, the solvent flow rate and the slag conveying speed of the bucket elevator.

[0025] The dense phase carbonization tower is used to carry out three-phase carbonization reaction of steel slag powder, realizing large-scale continuous carbon fixation of steel slag, realizing efficient recycling of steel slag, and reducing carbon emissions. It has the advantages of fast reaction rate, loose requirements on reaction atmosphere and temperature, simple device and no secondary pollution. The water content and carbon dioxide concentration of the steel slag in the tower are monitored by the monitoring module, and the injection amount of water and additives, as well as the conveying amount of steel slag are adjusted in real time accordingly, further improving the carbonization effect of steel slag.

[0026] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 A schematic structural diagram of a dense phase steel slag carbonization device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the technical solutions and beneficial effects of the present application more obvious and understandable, the technical solutions in the embodiments of the present application are clearly and completely described below by listing specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0031] It should be noted that the terms "first", "second", etc. used in this application can be used to describe various elements in this article, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element, rather than to describe a specific order or sequence.

[0032] It can be understood that in the context of this application, "connection" means that there is mutual transmission of electrical signals or data between the connected end and the connected end, which can be understood as "electrical connection", "communication connection", etc. In the context of this application, "A is directly connected to B" means that there are no other components between A and B except wires.

[0033] The embodiment of the present application provides a dense phase steel slag carbonization device, including: a bucket elevator 3, a dense phase carbonization tower 4, a spray device 6, an intermediate bin, a finished product bin 18 and a monitoring module 8. The bucket elevator 3 is used to deliver the steel slag powder from the first conveying device 23 to the dense phase carbonization tower. The bucket elevator 3 lifts the steel slag powder 17 to the top of the dense phase carbonization tower 4 and delivers it to the dense phase carbonization tower 4 through the steel slag inlet 42. The bucket elevator 3 is selected from the types of chain bucket elevator, plate chain bucket elevator or belt bucket elevator. The bucket elevator 3 is controlled by the bucket elevator control device to realize the control of the steel slag conveying speed.

[0034] The dense phase carbonization tower 4 includes a flue gas inlet 41, a slag inlet 42, a reaction chamber 40, a flue gas outlet 45 and an ash hopper. The flue gas inlet 41, the slag inlet 42 and the spray device 6 are arranged at the top of the carbonization tower 4. The intermediate bin 16 is arranged between the flue gas outlet 45 and the finished product bin 18, and is used to screen and collect the slag output with the flue gas. The dense phase carbonization tower 4 is used to make the slag and the flue gas fully react. Optionally, the dense phase carbonization tower 4 is cylindrical.

[0035] Flue gas containing carbon dioxide enters the reaction chamber 40 from the flue gas inlet 41. The spray device 6 is used to spray water and additives into the dense phase carbonization tower 4 to slurry the steel slag to improve the carbonization efficiency. The reaction chamber 40 is used to cause the steel slag, water and carbon dioxide entering the dense phase carbonization tower 4 to undergo a three-phase carbonization reaction in the dense phase carbonization tower 4. The flue gas after the reaction is discharged from the flue gas outlet 45. The carbonized steel slag after the reaction is discharged from the flue gas outlet 45 with the flue gas and enters the intermediate bin 16. Preferably, the spray device 6 includes a plurality of injection ports, which are respectively arranged at the top, middle and lower parts of the reaction chamber 40 of the dense phase carbonization tower 4 to further improve the carbonization efficiency.

[0036] A flexible stirring device 7 is distributed inside the dense phase carbonization tower 4 and is arranged in the reaction chamber 40 to fully react water, additives and / or steel slag powder. The flexible stirring device 7 can drive the steel slag powder slurry to rotate and flow, fully and evenly react the gas with the rotating slurry, prevent the slurry from accumulating and agglomerating, and prevent turbulence. The stirring paddle of the flexible stirring device 7 is arranged on the stirring shaft, and the number of stirring paddles can be one, two or more. The flexible stirring device 7 is selected from anchor type, propeller type, disc type, turbine type, spiral ribbon type, paddle type, etc.

[0037] The monitoring module 8 is used to monitor the water content and carbon dioxide concentration of the steel slag in the dense carbonization tower 4, and adjust the amount of water, additives and / or steel slag powder added according to the water content and carbon dioxide concentration in real time to achieve the best steel slag carbonization effect. Preferably, the monitoring module 8 is arranged in the middle and lower parts of the dense carbonization tower 4 to improve the accuracy of monitoring. The monitoring module 8 arranged in the middle is used to monitor the carbon dioxide concentration and the humidity of the steel slag, and feed back to the bucket elevator 3 and the water flow meter 14 to adjust the feeding speed and humidification amount of the steel slag. The monitoring module 8 arranged in the lower part is used to monitor the humidity of the steel slag to ensure that the steel slag is in a dry state when entering the intermediate bin 16. The bottom of the dense carbonization tower 4 is connected to part of the flue gas at the outlet of the chimney 10, so that the bottom steel slag reacts fully again and prevents the steel slag from hardening. The steel slag deposited in the carbonization tower 4 returns to the bucket elevator 3 again through the first conveying device 23.

[0038] The monitoring module 8 is respectively connected to the flow meter 14, the regulating valve 13, the water pump 12 and the bucket elevator control device, and the monitoring module 8 controls the water output and the solvent flow of the spray device 6 according to the flow meter 14. The water pump 12 is respectively connected to the water tank 11 and the solvent tank 15, and the water tank 11 and the solvent tank 15 are in parallel relationship.

[0039] The dust collector 1 is used to separate the powder from the flue gas containing the slag powder. Optionally, the dust collector 1 includes an electric dust collector or a bag dust collector. The size of the dust collector 1 is selected according to the amount of flue gas.

[0040] The second conveying device 24 is disposed below the dust collector 1, and is used to transport the slag powder to the finished product bin 18. Optionally, the second conveying device 24 includes a belt type, a spiral type, a pipeline type, and the like.

[0041] The fluidizing device 21 is located around the ash hopper at the bottom of the dense phase carbonization tower 4. Part of the flue gas discharged from the chimney returns to the dense phase carbonization tower 4 through the root valve 19 and the check valve 20. The flue gas flow rate is adjusted to make the steel slag falling into the ash hopper fluidized to prevent accumulation and compaction. Optionally, the fluidizing device 21 includes a silo fluidizer, a disk fluidizer, a disc fluidizer, etc. The accumulation and compaction of the steel slag solvent falling into the ash hopper at the bottom of the dense phase carbonization tower 4 will affect the operation of the system and reduce the carbonization efficiency. Part of the flue gas from the chimney outlet is led out through the fluidizing device 21 and returned to the ash hopper, so that the steel slag is re-fluidized and enters the intermediate bin 16 after being fully carbonized. The repose angle of steel slag is generally 50-60°, so the ash hopper angle is greater than or equal to 60°.

[0042] The slag adding device 22 is used to put the slag into the first conveying device 23. Optionally, a magnetic separation device can be added to the front end of the slag adding device 22. The first conveying device 23 conveys the slag to the bucket elevator 3.

[0043] The dense phase carbonization tower 4 and the dust collector 1 are connected by an intermediate bin 16, which serves as an inertial settling device to perform particle size classification and extend the service life of the dust collector. When the flue gas and slag are sent from the dense phase carbonization tower 4 to the dust collector 1, the carbonized slag falls into the bin due to gravity when passing through the intermediate bin 16, and the intermediate bins 16 at different positions can collect carbonized slag with different particle size distributions.

[0044] The dust collector 1 is also connected to a chimney 10 via a fan 9. The fan 9 can increase the gas pressure to facilitate gas discharge.

[0045] The finished product bin 18 is used to collect the carbonized steel slag from the bottom ash hopper of the dense phase carbonization tower 4 and the intermediate bin 16. The carbonized steel slag collected in the ash hopper by the dust collector 1 is transported to the finished product bin 18 by the second conveying device 24 for storage.

[0046] The reaction chamber 40 of the dense phase carbonization tower 4 includes five areas: a rectifying area 401, a main reaction area 402, a dynamic adjustment area 403, a reaction adjustment area 404, and a fluidized area 405. The monitoring module 8 controls the water output of the spray device 6, the solvent flow rate and the slag conveying speed of the bucket elevator 3, thereby dynamically adjusting the reaction conditions.

[0047] A guide plate is provided in the rectification area to ensure that the flow field is uniform and stable when the flue gas and materials pass through the guide plate, and to minimize eddy currents. The main reaction area is used to complete most of the carbonization reaction. The dynamic adjustment area is used to monitor and optimize the amount of reactant addition. The monitoring module calculates the actual amount of material addition required for water, additives and steel slag to ensure the optimal carbonization efficiency with the lowest energy and material consumption. In the reaction adjustment area, the monitoring module automatically adjusts the amount of reactant addition according to the calculated amount of material addition to ensure that the steel slag is in a dry state at the flue gas outlet.

[0048] The working principle of the dense phase steel slag carbonization device in the embodiment of the present application is as follows:

[0049] After dust removal, the flue gas discharged from the sintering machine enters the dense phase carbonization tower 4 through the flue gas inlet 41. At the same time, the steel slag powder is lifted to the top of the dense phase carbonization tower 4 by the bucket elevator 3, and the water and solvent additives are injected into the dense phase carbonization tower 4 through the spray device 6 after passing through the water pump 12, the regulating valve 13, and the flow meter 14 in sequence. The injection position is the top and side of the carbonization tower, and multiple spraying positions can be arranged according to production needs.

[0050] The spraying point at the top continuously adds water and solvent additives, which react with the steel slag powder and then react with the carbon dioxide in the flue gas to achieve the purpose of decarbonization.

[0051] The flue gas flows in the same direction as the solid reactant, from the top of the tower to the bottom of the tower. The dusty flue gas after decarbonization enters the intermediate bin 16, and falls into the ash hopper of the intermediate bin 16 step by step according to the particle size from large to small, and obtains carbonized steel slag.

[0052] The dusty flue gas enters the dust collector 1 through the intermediate bin 16 and is then discharged. The steel slag powder that falls into the lower ash hopper in the dense phase carbonization tower 4 enters the first conveying device 23 after regular cleaning, and then enters the bucket elevator 3 again to enter the next cycle. Through multiple cycles of carbonization, the carbonization effect of the steel slag is improved.

[0053] The monitoring module 8 is distributed on the inner side of the carbonization tower, and is used to monitor the water content and carbon dioxide concentration of the slag in the tower, and feed back to the flow meter 14 and the bucket elevator 3, so as to adjust the injection amount of water and solvent additives and the conveying amount of slag in real time to achieve the best slag carbonization effect.

[0054] The flexible stirring device 7 disposed inside the dense phase carbonization tower 4 has a power source at the upper end, which drives the stirring device 7 inside the carbonization tower to start stirring, and the stirring device 7 drives the steel slag powder slurry to rotate and flow. The plate stirring blades on the stirring device 7 diffuse the gas again, and then react with the rotating slurry fully and evenly. The rotating slurry passes through the inner wall of the carbonization tower to form a vortex and reacts evenly with the gas again. The slurry and gas pass through the rectification zone 401, the main reaction zone 402, the dynamic adjustment zone 403, and the reaction adjustment zone 404 in turn. At the same time, the humidity, the amount of additive injection, and the steel slag feeding speed are adjusted to ensure the best carbonization effect.

[0055] The carbonized slag enters the intermediate bin 16 in order of particle size from large to small, and the gas enters the dust collector 1 and is discharged from the chimney through the fan. The flue gas at the chimney outlet is partially led back to the bottom of the dense phase carbonization tower 4 to fluidize the slag falling into the bottom of the dense phase carbonization tower 4 to prevent the ash hopper from accumulating and hardening, and to fully carbonize the slag.

[0056] The carbonized steel slag collected by the intermediate bin 16 and the ash hopper of the dust collector 1 eventually enters the finished product bin 18. The steel slag entering the ash hopper at the bottom of the dense phase carbonization tower 4 is regularly cleaned and reintroduced into the bucket elevator 3.

[0057] Taking advantage of the technical advantages of the dense phase coherent tower technology in terms of gas-solid-water three-phase full reaction, combined with the technical requirements of steel slag carbonization, monitoring module 8 is added to simultaneously detect the water content of steel slag and the content of gaseous carbon dioxide. Compared with the traditional steel slag curing box process, the device is more flexible, the carbon fixation reaction is more complete and efficient, and it is more suitable for the carbonization of steel slag in industrial flue gas and industrial production processes, which is conducive to the large-scale development and application of steel slag carbonization technology.

[0058] For the relevant contents of each unit in this embodiment, reference may be made to the relevant contents of the units with the same figure marks in any of the foregoing embodiments, and will not be repeated here.

[0059] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A dense phase steel slag carbonization device, characterized in that: include: Bucket elevator, dense phase carbonization tower, spray device, intermediate bin, finished product bin and monitoring module; The dense phase carbonization tower comprises a flue gas inlet, a steel slag inlet, a reaction chamber, a flue gas outlet and an ash hopper; flue gas containing carbon dioxide enters the reaction chamber from the flue gas inlet; The bucket elevator is used to transport the steel slag powder from the first conveying device into the dense phase carbonization tower; The spraying device is used to spray water and additives into the reaction chamber of the dense phase carbonization tower; The intermediate bin is arranged between the smoke outlet and the finished product bin, and is used to screen and collect the steel slag output along with the smoke; The reaction chamber is used to cause the steel slag, water and carbon dioxide entering the dense phase carbonization tower to undergo a three-phase carbonization reaction; the flue gas after the reaction is discharged from the flue gas outlet; the carbonized steel slag after the reaction is discharged along with the flue gas and enters the intermediate bin; The monitoring module is used to monitor the water content and carbon dioxide concentration of the steel slag in the dense phase carbonization tower, and to adjust the addition amount of the water, the additive and / or the steel slag powder in real time according to the water content and the carbon dioxide concentration; The finished product bin is used to collect carbonized steel slag from the ash hopper and the intermediate bin.

2. The dense phase steel slag carbonization device according to claim 1, characterized in that: The dense phase carbonization tower includes a rectifying zone, a main reaction zone, a dynamic adjustment zone, and a reaction adjustment zone; a guide plate is provided in the rectifying zone to ensure that the flow field of the flue gas and the material is uniform and stable when passing through the guide plate; The main reaction zone is used to complete most of the carbonization reaction; the dynamic adjustment zone is used to monitor and optimize the amount of reactant addition; in the reaction adjustment zone, the monitoring module automatically adjusts the amount of reactant addition according to the calculated amount of material addition.

3. The dense phase steel slag carbonization device according to claim 1, characterized in that: The injection ports of the spray device are respectively arranged at the top, middle and bottom of the reaction chamber.

4. The dense phase steel slag carbonization device according to claim 1, characterized in that: It also includes a dust collector, which is connected to the intermediate bin and is used to remove dust from the flue gas discharged from the intermediate bin and discharge clean flue gas.

5. The dense phase steel slag carbonization device according to claim 4, characterized in that: It also includes a chimney, which is connected to the dust collector through a fan and is used to discharge the smoke after the dust is removed.

6. The dense phase steel slag carbonization device according to claim 1, characterized in that: It also includes a flexible stirring device, which is arranged in the reaction chamber and is used to make the water, the additive and / or the steel slag powder react fully.

7. The dense phase steel slag carbonization device according to claim 5, characterized in that: It also includes a fluidizing device connected between the chimney and the ash hopper at the bottom of the dense phase carbonization tower, and used for returning part of the flue gas discharged from the chimney to the ash hopper.

8. The dense phase steel slag carbonization device according to claim 1, characterized in that: The first conveying equipment is arranged below the dense phase carbonization tower, and is used to convey the steel slag powder discharged from the ash hopper at the bottom of the dense phase carbonization tower to the bucket elevator again.

9. The dense phase steel slag carbonization device according to claim 4, characterized in that: A second conveying device is provided below the dust collector for conveying the carbonized steel slag collected by the dust collector to the finished product bin.

10. The dense phase steel slag carbonization device according to claim 1, characterized in that: The monitoring module is respectively connected to the flow meter, the regulating valve, the water pump and the bucket elevator control device, and is used to control the water output of the spray device, the solvent flow rate and the slag conveying speed of the bucket elevator.

Images