A hot blast furnace flue gas treatment system

Abstract

This utility model discloses a flue gas treatment system for a hot blast stove, including a flue gas central pipe, a collection pipe, a flue gas extraction fan, a flue gas conveying pipe, a centralized treatment tank, and an exhaust pipe. Several collection pipes are connected to the flue gas central pipe; the flue gas outlet of each collection pipe is connected to the central pipe, and the flue gas inlet of each collection pipe is connected to the exhaust port of the hot blast stove. The flue gas outlet of the central pipe is connected to the extraction fan, and the outlet of the extraction fan is connected to the flue gas conveying pipe. The flue gas outlet of the conveying pipe faces the centralized treatment tank, forming an angle of 70° to 100° with the liquid surface of the tank. The exhaust pipe is located above the end of the centralized treatment tank furthest from the conveying pipe, and its flue gas inlet faces the tank. This utility model can be adapted to treat the flue gas of multiple hot blast stoves, reducing flue gas treatment costs and equipment footprint.

Description

Technical Field

[0001] This utility model relates to the technical field of grain drying equipment, and in particular to a hot air furnace flue gas treatment system. Background Technology

[0002] Currently, to achieve centralized and rapid grain drying, there exists a drying line consisting of multiple dryers and hot air furnaces. The flue gas produced by the existing hot air furnaces is simply purified by the furnace itself before being directly discharged into the environment. This method is only suitable for use in areas without residential areas around the drying plant or in suburban areas without environmental requirements. In areas with residential areas or special environmental requirements around the drying plant, the flue gas from the hot air furnaces needs to undergo secondary treatment before being released into the environment.

[0003] In the existing technology, the flue gas treatment for a single hot air furnace is mainly carried out by cyclone dust collectors. Although it can achieve the effect of flue gas purification, it has the disadvantages of high equipment cost and large footprint, and it is not suitable for mass production use in drying lines composed of multiple hot air furnaces.

[0004] Therefore, it is urgent to research and develop a flue gas treatment system that can be applied to the treatment of flue gas from multiple hot blast stoves, in order to solve the above-mentioned technical defects. Utility Model Content

[0005] The purpose of this utility model is to solve the above-mentioned technical problems and provide a hot blast stove flue gas treatment system. This hot blast stove flue gas treatment system can be adapted to the flue gas treatment of multiple hot blast stoves, reducing the cost of flue gas treatment and the equipment footprint.

[0006] To achieve the above objectives, this utility model provides a hot blast stove flue gas treatment system, the specific implementation of which is as follows:

[0007] A hot blast furnace flue gas treatment system includes a flue gas central pipe, a collection pipe, a flue gas extraction fan, a flue gas conveying pipe, a central treatment tank, and a flue gas exhaust pipe.

[0008] The flue gas collection pipe is connected to several collection pipes. The flue gas outlet of the collection pipe is connected to the flue gas collection pipe, and the flue gas inlet of the collection pipe is connected to the exhaust port of the hot air furnace.

[0009] The flue gas outlet of the flue gas collection pipe is connected to the smoke extraction fan, the air outlet of the smoke extraction fan is connected to the flue gas conveying pipe, and the flue gas outlet of the flue gas conveying pipe faces the centralized treatment tank, forming an angle of 70° to 100° with the liquid surface of the centralized treatment tank.

[0010] The exhaust pipe is located above the end of the centralized treatment tank away from the flue gas delivery pipe, and the flue gas inlet of the exhaust pipe faces the centralized treatment tank.

[0011] This utility model discloses a hot blast stove flue gas treatment system. Compared with existing technologies, it utilizes a flue gas central pipe and several collection pipes in conjunction to collect flue gas from multiple hot blast stoves into the same central pipe. A flue gas extraction fan then transfers the flue gas from the central pipe to a flue gas delivery pipe. The flue gas, passing through the flue gas outlet of the delivery pipe, impacts the liquid surface of the central treatment tank at an angle of 70° to 100°. This ensures full contact and deflection of the flue gas and liquid surface. Fine particles in the flue gas are separated and captured by the liquid due to the inertial force generated by the deflection. Harmful gases in the flue gas react and separate from the liquid surface after sufficient contact. Finally, the flue gas is purified and cooled in the central treatment tank before being discharged from the exhaust pipe for subsequent emissions. This system achieves the purification of flue gas from multiple hot blast stoves in a single central treatment tank, effectively reducing the cost of flue gas treatment and the required equipment footprint.

[0012] Furthermore, the flue gas outlet of the flue gas conveying pipe is perpendicular to the liquid level of the centralized treatment tank.

[0013] By vertically positioning the flue gas outlet of the flue gas delivery pipe and the liquid surface of the centralized treatment tank, the flue gas can directly impact the liquid surface in a vertical direction. This maximizes the contact area and intensity between the flue gas and the liquid surface, which is most conducive to the rapid capture of pollutants (such as fine particles) in the flue gas by the liquid, thereby improving the purification efficiency and effectiveness of the flue gas.

[0014] Furthermore, the centralized processing pool is provided with a notch.

[0015] By setting gaps in the centralized treatment tank, it is possible to observe the liquid level inside the tank and to clean up the waste inside.

[0016] Furthermore, the centralized treatment tank is equipped with a sealing element, and the flue gas outlet of the flue gas conveying pipe and the flue gas inlet of the exhaust pipe both extend through the sealing element into the centralized treatment tank;

[0017] The projected area of ​​the seal on the centralized treatment tank accounts for 60% to 80% of the centralized treatment tank.

[0018] By installing a seal on the centralized treatment tank, the space above the liquid surface of the centralized treatment tank is effectively isolated from the external environment, forming a basically sealed treatment chamber. This ensures that all introduced flue gas must be treated at the liquid surface before being discharged from the exhaust pipe, fundamentally preventing the leakage of untreated flue gas. At the same time, the seal is designed so that its projected area on the centralized treatment tank occupies 60% to 80% of the tank area, ensuring good sealing while still providing necessary maintenance and observation windows.

[0019] Furthermore, the distance between the flue gas outlet of the flue gas conveying pipe and the flue gas inlet of the exhaust pipe, projected onto the seal, occupies 20% to 50% of the area of ​​the seal.

[0020] By setting the projected area of ​​the distance between the flue gas outlet of the flue gas conveying pipe and the flue gas inlet of the exhaust pipe on the seal to occupy 20% to 50% of the seal, it is possible to avoid the situation where the distance between the two is too small, resulting in airflow short-circuiting and excessive local disturbance of the liquid surface, or the distance between the two is too large, increasing the flow resistance of the flue gas, causing bubble coalescence and uneven flue gas treatment.

[0021] Furthermore, the centralized treatment pool is equipped with a sewage outlet.

[0022] By installing a drain outlet on the centralized treatment tank, liquids and waste inside the tank can be directly discharged when cleaning the tank.

[0023] Furthermore, the centralized treatment tank is pre-filled with a flue gas treatment liquid that can chemically react with the flue gas.

[0024] By pre-filling a flue gas treatment liquid that can chemically react with the flue gas in a centralized treatment tank, the flue gas treatment liquid is selected according to the harmful components in the flue gas of the hot blast stove. Limestone (desulfurization), alkaline solution (for treating acidic gases, sulfur dioxide, and nitrogen oxides), potassium permanganate solution (nitrides), and activated carbon suspension are added to the flue gas treatment liquid to adapt to the treatment of different flue gases.

[0025] Furthermore, the flue gas velocity discharged from the flue gas outlet of the flue gas conveying pipe is 8 to 12 m / s.

[0026] By setting the velocity of the flue gas discharged from the flue gas outlet of the flue gas conveying pipe to 8 to 12 m / s, it is ensured that the flue gas jet has sufficient momentum to penetrate the liquid surface, overcome the surface tension, and form a dense and well-dispersed bubble group. This greatly expands the specific surface area of ​​the gas-liquid two-phase contact, while avoiding excessively high velocity that would cause the bubbles to be too fine, merge too quickly, or generate violent droplet entrainment.

[0027] Furthermore, the cross-sectional flue gas rising velocity of the flue gas treatment liquid in the centralized treatment tank is 2 to 3 m / s.

[0028] By controlling the upward velocity of the flue gas in the cross-section of the flue gas treatment liquid in the centralized treatment tank to 2 to 3 m / s, it is ensured that the bubbles have enough time to rise, slide and fully contact the liquid, so that the mass transfer of pollutants to the liquid phase and subsequent chemical reactions can be fully carried out, thereby improving the flue gas treatment efficiency.

[0029] Furthermore, the flue gas inlet of the exhaust pipe is equipped with a flue gas collection hood, and both sides of the flue gas collection hood are inclined outwards in the direction close to the centralized treatment pool.

[0030] By installing flue gas collection hoods that slope outwards towards the centralized treatment tank on both sides at the flue gas inlet of the exhaust pipe, the effective gas collection area of ​​the exhaust pipe is increased. This guides the fully reacted flue gas in the liquid surface area of ​​the treatment tank to converge at the inlet of the exhaust pipe, reducing the disorderly diffusion and eddy retention of flue gas in the space above the liquid surface. This ensures that the treated gas is collected and discharged efficiently and evenly, improving the overall flow efficiency and operational stability of the system.

[0031] Based on the above technical solution, this utility model has the following beneficial effects compared with the prior art:

[0032] By employing a combined flue gas central pipe and several collection pipes, the flue gas from several hot blast stoves is collected into the same central pipe. A flue gas extraction fan then transfers the flue gas from the central pipe to a flue gas delivery pipe. The flue gas exits through the delivery pipe and impacts the liquid surface of the centralized treatment tank at a 70° to 100° angle. This ensures thorough contact and deflection of the flue gas and liquid surface. Fine particles in the flue gas are separated and captured by the liquid due to the inertial force generated by the deflection. Harmful gases in the flue gas react and separate from the liquid surface after thorough contact. Finally, the flue gas is purified and cooled in the centralized treatment tank before being discharged from the exhaust pipe for subsequent emissions. This method achieves the purification of flue gas from several hot blast stoves in a single centralized treatment tank, effectively reducing the cost of flue gas treatment and the required equipment footprint. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of this utility model;

[0034] Figure 2 For the present utility model Figure 1 A magnified view of a portion of the image;

[0035] Figure 3 This is a schematic diagram of the structure of this utility model in conjunction with a hot air furnace.

[0036] Explanation of reference numerals in the attached figures:

[0037] 100. Centralized flue gas pipe; 200. Collection pipe; 300. Smoke extraction fan; 400. Flue gas conveying pipe; 500. Centralized treatment tank; 510. Notch; 520. Seal; 530. Drain outlet; 540. Guide surface; 600. Exhaust pipe; 610. Flue gas collection hood. Detailed Implementation

[0038] To facilitate understanding of this utility model, the specific embodiments of this utility model will be described in more detail below with reference to the accompanying drawings.

[0039] Unless otherwise specified or defined, the terms "first," "second," etc., used in this document are for distinguishing names only and do not represent a specific number or order.

[0040] Unless otherwise specified or defined, the term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0041] It should be noted that in this article, "fixed to" or "connected to" can mean directly fixed to or connected to a component, or indirectly fixed to or connected to a component.

[0042] like Figure 1-3 The hot blast furnace flue gas treatment system shown includes a flue gas central pipe 100, a flue gas extraction fan 300, a flue gas conveying pipe 400, a centralized treatment tank 500, and a flue gas exhaust pipe 600. Several collection pipes 200 are connected to the flue gas central pipe 100. Each collection pipe 200 communicates with the flue gas central pipe 100 and is connected to a hot blast furnace, so as to collect and transfer the flue gas from the exhaust port of the hot blast furnace into the flue gas central pipe 100, thereby achieving the effect of collecting the flue gas of several hot blast furnaces through a single flue gas central pipe 100.

[0043] The flue gas outlet of the flue gas collection pipe 100 is connected to the smoke extraction fan 300, and the air outlet of the smoke extraction fan 300 is connected to the flue gas conveying pipe 400. The operation of the smoke extraction fan 300 is used to draw the flue gas in the flue gas collection pipe 100 and transfer it to the flue gas conveying pipe 400.

[0044] The smoke extraction fan 300 described in this embodiment can be any existing smoke extraction fan.

[0045] The flue gas outlet of the flue gas conveying pipe 400 faces the centralized treatment tank 500, and the flue gas outlet of the flue gas conveying pipe 400 forms an angle of 70° to 100° with the liquid surface of the centralized treatment tank 500. This allows the flue gas and the liquid surface to fully contact and change direction. The fine particles in the flue gas are separated and captured by the liquid due to the inertial force generated by the change of the flue gas. The harmful gases in the flue gas react and separate from the flue gas after fully contacting the liquid surface.

[0046] Specifically, in this embodiment, the flue gas outlet of the flue gas conveying pipe 400 is preferably perpendicular to the liquid surface of the centralized treatment tank 500, so that the flue gas can directly impact the liquid surface in a vertical direction. This maximizes the contact area and intensity between the flue gas and the liquid surface, which is most conducive to the rapid capture of pollutants (such as fine particles) in the flue gas by the liquid, thereby improving the purification efficiency and effect of the flue gas.

[0047] A notch 510 is provided on the centralized treatment tank 500 to observe the liquid level in the centralized treatment tank 500 and to clean up the waste inside the centralized treatment tank 500.

[0048] A sealing element 520 is provided in the centralized treatment tank 500. The flue gas outlet of the flue gas conveying pipe 400 and the flue gas inlet of the exhaust pipe 600 both extend into the centralized treatment tank 500 through the sealing element 520. This effectively isolates the space above the liquid surface of the centralized treatment tank 500 from the external environment, forming a basically sealed treatment chamber. This ensures that all introduced flue gas must be treated at the liquid surface before being discharged from the exhaust pipe 600, fundamentally preventing the leakage of untreated flue gas.

[0049] Furthermore, the projected area of ​​the seal 520 on the centralized treatment tank 500 occupies 60% to 80% of the centralized treatment tank 500. While ensuring good sealing performance, necessary maintenance and observation windows (the notch 510) are still reserved.

[0050] Understandably, the notch 510 can also be sealed with a sealing plate made of transparent material (such as a flip-top structure seal) to further prevent the leakage of untreated flue gas.

[0051] The distance between the flue gas outlet of the flue gas conveying pipe 400 and the flue gas inlet of the exhaust pipe 600, projected onto the sealing element 520, accounts for 20% to 50% of the area of ​​the sealing element 520. This avoids situations where the distance is too small, leading to airflow short-circuiting and excessive local disturbance of the liquid surface, or where the distance is too large, increasing the flow resistance of the flue gas and causing bubble coalescence and uneven flue gas treatment.

[0052] The centralized treatment tank 500 is equipped with a sewage outlet 530 so that liquids and garbage inside the centralized treatment tank 500 can be directly discharged when cleaning the centralized treatment tank 500. In actual use, sewage and garbage can be transferred to the outside through sewage pipes.

[0053] Furthermore, a guide surface 540 is provided in the centralized treatment tank 500. The guide surface 540 slopes downward from the end away from the sewage outlet 530 to the end closer to the sewage outlet 530, so as to guide the liquid and garbage in the centralized treatment tank 500 to the sewage outlet 530 and improve the sewage discharge efficiency.

[0054] The exhaust pipe 600 is provided above the end of the centralized treatment tank 500 away from the flue gas conveying pipe 400. The flue gas inlet of the exhaust pipe 600 faces the centralized treatment tank 500, so as to transfer and discharge the flue gas purified by the centralized treatment tank 500 through the exhaust pipe 600.

[0055] The flue gas inlet of the exhaust pipe 600 is equipped with a flue gas collection hood 610. Both sides of the flue gas collection hood 610 are inclined outward along the direction close to the centralized treatment tank 500, which increases the effective gas collection area of ​​the exhaust pipe 600. This guides the flue gas that has been fully reacted in the liquid surface area of ​​the treatment tank to converge towards the inlet of the exhaust pipe 600, reducing the disorderly diffusion and eddy retention of flue gas in the space above the liquid surface. This ensures that the treated gas is collected and discharged efficiently and uniformly, improving the overall flow efficiency and operational stability of the system.

[0056] The centralized treatment tank 500 is pre-filled with a flue gas treatment liquid that can chemically react with the flue gas. In actual use, the flue gas treatment liquid uses water as a medium, and the added components are selected according to the harmful components that need to be removed from the flue gas, such as limestone (desulfurization), alkaline solution (for treating acidic gases, sulfur dioxide, and nitrogen oxides), potassium permanganate solution (nitrides), and activated carbon suspension, which can adapt to the treatment requirements of different flue gases.

[0057] The flue gas velocity discharged from the flue gas outlet of the flue gas conveying pipe 400 is 8 to 12 m / s, ensuring that the flue gas jet has sufficient momentum to penetrate the liquid surface, overcome surface tension, and form a dense and well-dispersed bubble group. This greatly expands the specific surface area of ​​the gas-liquid two-phase contact, while avoiding excessively high velocity that would cause the bubbles to be too fine, merge too quickly, or generate violent droplet entrainment.

[0058] In actual use, the speed of the flue gas discharged from the flue gas outlet of the flue gas conveying pipe 400 is controlled by controlling the rotation speed of the exhaust fan 300.

[0059] The cross-sectional flue gas rising velocity of the flue gas treatment liquid in the centralized treatment tank 500 is 2 to 3 m / s, ensuring that the bubbles have enough time to rise, slide and fully contact the liquid, so that the mass transfer of pollutants to the liquid phase and subsequent chemical reactions can be fully carried out, thereby improving the flue gas treatment efficiency.

[0060] The upward velocity of the flue gas across the cross-section of the flue gas treatment liquid depends on the velocity of the flue gas discharged from the flue gas outlet. The faster the velocity of the flue gas discharged from the flue gas outlet, the faster the upward velocity of the flue gas across the cross-section of the flue gas treatment liquid.

[0061] Of course, an air blowing mechanism, such as a blower or air pump, can also be installed in the centralized treatment tank 500 to increase the cross-sectional velocity of the flue gas rising from the flue gas treatment liquid. This will not be described in detail here.

[0062] This embodiment provides a hot blast stove flue gas treatment system. Compared to existing technologies, it utilizes a flue gas central pipe and several collection pipes to collect flue gas from multiple hot blast stoves into the same central pipe. A flue gas extraction fan then transfers the flue gas from the central pipe to a flue gas delivery pipe. The flue gas exits through the delivery pipe and impacts the liquid surface of the central treatment tank at a 70° to 100° angle. This ensures thorough contact and deflection of the flue gas and liquid surface. Fine particles in the flue gas are separated and captured by the liquid due to the inertial force generated by the deflection. Harmful gases in the flue gas react and separate from the liquid surface after thorough contact. Finally, the flue gas is purified and cooled in the central treatment tank before being discharged from the exhaust pipe for subsequent emissions. This system achieves the purification of flue gas from multiple hot blast stoves in a single central treatment tank, effectively reducing the cost and footprint of flue gas treatment equipment.

[0063] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments disclosed and described above, and some modifications and changes to this utility model should also fall within the protection scope of the claims of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. A hot blast stove flue gas treatment system, characterized in that, It includes a flue gas central pipe (100), a collection pipe (200), a smoke extraction fan (300), a flue gas conveying pipe (400), a central treatment tank (500), and a smoke exhaust pipe (600); A plurality of collecting pipes (200) are connected to the flue gas concentrator (100), the flue gas outlet of the collecting pipe (200) is connected to the flue gas concentrator (100), and the flue gas inlet of the collecting pipe (200) is connected to the exhaust port of the hot blast stove. The flue gas outlet of the flue gas collection pipe (100) is connected to the smoke extraction fan (300), the air outlet of the smoke extraction fan (300) is connected to the flue gas conveying pipe (400), and the flue gas outlet of the flue gas conveying pipe (400) faces the centralized treatment tank (500) and forms an angle of 70° to 100° with the liquid surface of the centralized treatment tank (500). The exhaust pipe (600) is located above the end of the centralized treatment tank (500) away from the flue gas conveying pipe (400), and the flue gas inlet of the exhaust pipe (600) faces the centralized treatment tank (500).

2. The hot blast stove flue gas treatment system as described in claim 1, characterized in that, The flue gas outlet of the flue gas conveying pipe (400) is perpendicular to the liquid surface of the centralized treatment tank (500).

3. The hot blast stove flue gas treatment system as described in claim 1 or 2, characterized in that, The centralized treatment pool (500) is provided with a notch (510).

4. The hot blast stove flue gas treatment system as described in claim 3, characterized in that, The centralized treatment tank (500) is provided with a sealing element (520), and the flue gas outlet of the flue gas conveying pipe (400) and the flue gas inlet of the exhaust pipe (600) both extend through the sealing element (520) into the centralized treatment tank (500). The projected area of ​​the seal (520) on the centralized treatment tank (500) accounts for 60% to 80% of the centralized treatment tank (500).

5. The hot blast stove flue gas treatment system as described in claim 4, characterized in that, The distance between the flue gas outlet of the flue gas conveying pipe (400) and the flue gas inlet of the exhaust pipe (600) has a projected area on the seal (520) that occupies 20% to 50% of the seal (520).

6. The hot blast stove flue gas treatment system as described in claim 1 or 2, characterized in that, The centralized treatment tank (500) is equipped with a sewage outlet (530).

7. The hot blast stove flue gas treatment system as described in claim 1 or 2, characterized in that, The centralized treatment tank (500) is pre-filled with a flue gas treatment liquid that can chemically react with the flue gas.

8. The hot blast stove flue gas treatment system as described in claim 7, characterized in that, The flue gas velocity discharged from the flue gas outlet of the flue gas conveying pipe (400) is 8 to 12 m / s.

9. The hot blast stove flue gas treatment system as described in claim 8, characterized in that, The cross-sectional flue gas rising velocity of the flue gas treatment liquid in the centralized treatment tank (500) is 2 to 3 m / s.

10. The hot blast stove flue gas treatment system as described in claim 1 or 2, characterized in that, The flue gas inlet of the exhaust pipe (600) is provided with a flue gas collection hood (610), and both sides of the flue gas collection hood (610) are inclined outward in the direction close to the centralized treatment tank (500).

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