Carbon monoxide and nitrogen oxide coupled removal system

Abstract

This invention discloses a coupled carbon monoxide and nitrogen oxide removal system. The system includes a cyclone dust collector, a coupled removal device, and a quench tower. The cyclone dust collector is used for pre-collection of dust. The coupled removal device includes a central cylinder, an air supply mechanism, a CO burner, and a dry powder denitrification injection mechanism. The top of the central cylinder has an outlet flue, and the bottom has an inlet flue. The end of the inlet flue furthest from the central cylinder is connected to the cyclone dust collector. The dry powder denitrification injection mechanism, the CO burner, and the air supply mechanism are sequentially arranged along the height direction on the central cylinder between the inlet flue and the outlet flue. The quench tower is connected to the end of the outlet flue furthest from the central cylinder. The coupled carbon monoxide and nitrogen oxide removal system provided by this invention has the advantages of low retrofitting and operating costs and low energy consumption.

Description

Technical Field

[0001] This invention relates to the field of flue gas purification technology, and in particular to a coupled removal system for carbon monoxide and nitrogen oxides. Background Technology

[0002] Non-ferrous metal pyrometallurgical processes generate large amounts of flue gas, containing harmful substances such as dust, SO2, NOx, and CO. The current flue gas treatment process involves a multi-tube surface cooler – baghouse dust collector – wet desulfurization system – chimney. This process primarily removes dust and SO2 from the flue gas, but it doesn't effectively address the removal of NOx and CO. Furthermore, the NOx concentration in the flue gas is relatively high, approximately 300–600 mg / Nm3. With increasingly stringent environmental standards, NOx and CO removal from smelting flue gas is essential. Several existing treatment processes require placement downstream of the wet desulfurization system, necessitating reheating of the flue gas and incurring high catalyst manufacturing costs. Moreover, all of these process solutions lack practical engineering case studies and are awaiting industrial application. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a coupled carbon monoxide and nitrogen oxide removal system, which has the advantages of low modification and operating costs and low energy consumption.

[0004] According to an embodiment of the present invention, a carbon monoxide and nitrogen oxide coupled removal system includes a cyclone dust collector, a coupled removal device, and a quench tower. The cyclone dust collector is used for pre-collecting dust. The coupled removal device includes a central cylinder, an air supply mechanism, a CO burner, and a dry powder denitrification injection mechanism. The top of the central cylinder is provided with an outlet flue, and the bottom of the central cylinder is provided with an inlet flue. The end of the inlet flue away from the central cylinder is connected to the cyclone dust collector. The dry powder denitrification injection mechanism, the CO burner, and the air supply mechanism are sequentially arranged along the height direction on the central cylinder between the inlet flue and the outlet flue. The quench tower is connected to the end of the outlet flue away from the central cylinder.

[0005] The carbon monoxide and nitrogen oxide coupled removal system according to embodiments of the present invention has the advantages of low modification and operation costs and low energy consumption.

[0006] In some embodiments, the bottom of the central cylinder is provided with a lower ash hopper, the top of the central cylinder is provided with an upper cone, the outlet flue is connected to the top of the upper cone, and the inlet flue is connected to the lower part of the central cylinder.

[0007] In some embodiments, the air supply mechanism includes an annular air duct located above the inlet flue, the annular air duct supplying air into the central cylinder.

[0008] In some embodiments, the annular air duct is connected to the interior of the central cylinder through multiple branch air ducts, which are evenly distributed around the sidewalls of the central cylinder.

[0009] In some embodiments, at least a portion of the branch air ducts enter the interior of the central cylinder, and there is an angle α between the branch air ducts and the inner wall of the central cylinder, wherein the angle α ranges from 10° to 40°.

[0010] In some embodiments, the branch air ducts are equipped with control valves, and the number of branch air ducts is greater than or equal to three.

[0011] In some embodiments, the CO burner is disposed above the annular air duct and communicates with the interior of the central cylinder, and the dry powder denitrification injection mechanism is disposed above the CO burner and communicates with the interior of the central cylinder.

[0012] In some embodiments, there is an angle β between the CO burner and the inner wall of the central cylinder, and the angle β ranges from 20° to 60°.

[0013] In some embodiments, the carbon monoxide and nitrogen oxide coupled removal system further includes a rapid exhaust device, which includes a rapid exhaust valve, a rapid exhaust chimney, and a transmission mechanism. The rapid exhaust chimney is connected to the outlet flue, the rapid exhaust valve is located on the pipeline of the rapid exhaust chimney, and the transmission mechanism controls the opening and closing of the rapid exhaust valve.

[0014] In some embodiments, a pressure measuring point is provided on the outlet flue, and the pressure measuring point is interlocked with the transmission mechanism. Attached Figure Description

[0015] Figure 1 This is a front view of the central cylinder of the carbon monoxide and nitrogen oxide coupled removal system according to an embodiment of the present invention.

[0016] Figure 2 This is a cross-sectional view of the central cylinder of the carbon monoxide and nitrogen oxide coupled removal system according to an embodiment of the present invention.

[0017] Figure 3 This is a cross-sectional schematic diagram of the CO burner in the carbon monoxide and nitrogen oxide coupled removal system according to an embodiment of the present invention.

[0018] Figure 4 This is a schematic cross-sectional view of the branch duct of the carbon monoxide and nitrogen oxide coupled removal system according to an embodiment of the present invention.

[0019] Figure 5 This is a schematic diagram of the structure of the carbon monoxide and nitrogen oxide coupled removal system according to an embodiment of the present invention.

[0020] Attached reference numerals: 1. Rapid exhaust chimney; 2. Rapid exhaust valve; 3. Transmission mechanism; 4. Outlet flue; 5. Upper cone; 6. Dry powder denitrification injection channel; 7. Central cylinder; 8. CO burner; 9. Branch duct; 10. Annular duct; 11. Inlet flue; 12. Lower ash hopper; 13. Steel shell; 14. Ceramic fiber felt; 15. Lightweight castable; 16. High-strength wear-resistant castable; 17. Cyclone dust collector; 18. Removal device; 19. Quenching tower. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0022] like Figures 1 to 5 As shown, according to an embodiment of the present invention, a carbon monoxide and nitrogen oxide coupled removal system includes a cyclone dust collector 17, a coupled removal device 18, and a quench tower 19. The cyclone dust collector 17 is used for pre-collection of dust. The coupled removal device 18 includes a central cylinder 7, an air supply mechanism, a CO burner 8, and a dry powder denitrification injection mechanism. The top of the central cylinder 7 is provided with an outlet flue 4, and the bottom of the central cylinder 7 is provided with an inlet flue 11. The end of the inlet flue 11 away from the central cylinder 7 is connected to the cyclone dust collector 17. The dry powder denitrification injection mechanism, the CO burner 8, and the air supply mechanism are arranged sequentially along the height direction on the central cylinder 7 between the inlet flue 11 and the outlet flue 4. The quench tower 19 is connected to the end of the outlet flue 4 away from the central cylinder 7. The cyclone dust collector 17 adopts a single-stage or double-stage form with a cross-sectional wind speed of 3-5 m / s. The outer shell is made of steel, lined with high-strength wear-resistant castable 16 with a thickness ≥30mm. The CO burner 8, in conjunction with the dry powder denitrification injection mechanism, removes carbon monoxide and nitrogen oxides from the flue gas, achieving combined removal of these two substances. Compared to downstream removal processes requiring flue gas reheating, this method has lower construction and operating costs, lower upgrade and retrofit costs, and achieves compliant emissions, contributing to energy conservation and emission reduction. The central cylinder 7 uses a Q235 steel shell 13 (H0≥10mm), lined with refractory material with a temperature resistance >1000℃. From the outside in, the central cylinder 7 consists of ceramic fiber felt 14 (thickness H1≥50mm), lightweight castable 15 (thickness H2≥100mm), and high-strength wear-resistant castable 16 (thickness H3≥150mm), with an overall refractory material thickness H≥300mm.

[0023] The carbon monoxide and nitrogen oxide coupled removal system according to embodiments of the present invention achieves the combined removal of nitrogen oxides and carbon monoxide from flue gas, and has the advantages of low modification and operation costs and low energy consumption.

[0024] In some embodiments, such as Figure 1 As shown, the bottom of the central cylinder 7 is provided with a lower ash hopper 12, the top of the central cylinder 7 is provided with an upper cone, the outlet flue 4 is connected to the top of the upper cone, and the inlet flue 11 is connected to the lower part of the central cylinder 7.

[0025] Specifically, the flue gas enters from the inlet flue 11 at the bottom of the central cylinder 7, the residence time of the flue gas in the central cylinder 7 is greater than 2 seconds, the temperature of the flue gas exiting the outlet flue 4 is greater than 800℃, and the tilt angle of the lower ash hopper 12 is greater than or equal to 60°.

[0026] In some embodiments, such as Figure 1 As shown, the air supply mechanism includes an annular air duct 10, which is located above the inlet flue 11 and supplies air into the central cylinder 7.

[0027] Specifically, the annular air duct 10 is located above the inlet flue 11, and the distance between the annular air duct 10 and the inlet flue 11 in the height direction of the central cylinder 7 is greater than or equal to 500mm.

[0028] In some embodiments, such as Figure 1 and Figure 4 As shown, the annular air duct 10 is connected to the interior of the central cylinder 7 through multiple branch air ducts 9, and the branch air ducts 9 are evenly distributed around the side wall of the central cylinder 7.

[0029] Specifically, the branch air duct 9 is arranged obliquely along the side wall of the central cylinder 7, and the annular air duct 10 can make the air enter the central cylinder 7 evenly, and can make the flue gas mix with the air more fully.

[0030] In some embodiments, such as Figure 1 and Figure 4 As shown, at least part of the branch air duct 9 enters the interior of the central cylinder 7, and there is an angle α between the branch air duct 9 and the inner wall of the central cylinder 7, with the angle α ranging from 10° to 40°.

[0031] Specifically, the branch air ducts 9 and the inner wall of the central cylinder 7 are arranged at a certain angle and rotated. The rotational arrangement of multiple branch air ducts 9 causes the flue gas and air to mix and form a vortex flow that rises. Extending the residence time of the flue gas in the central cylinder 7 also allows the flue gas and air to mix fully.

[0032] In some embodiments, the branch air duct 9 is provided with a control valve, and the number of branch air ducts 9 is greater than or equal to 3.

[0033] Specifically, the control valve is a butterfly valve, which is installed on the branch duct 9 to regulate the air intake. Increasing the number of branch ducts 9 can increase the speed at which air enters the central cylinder 7, making the branch ducts 9 form a more stable vortex flow and prolonging the residence time of the flue gas.

[0034] In some embodiments, such as Figure 1 and Figure 3 As shown, the CO burner 8 is located above the annular air duct 10 and is connected to the interior of the central cylinder 7. The dry powder denitrification injection mechanism is located above the CO burner 8 and is connected to the interior of the central cylinder 7.

[0035] Specifically, there are 1 to 3 CO burners 8. Natural gas or diesel fuel is used. The PNCR injection mechanism includes a dry powder denitrification injection channel 6 and a denitrification agent storage tank. The dry powder denitrification injection channel 6 is located on the upper wall of the central cylinder 7, 200mm to 800mm below the upper cone 5. There is at least one PNCR injection channel 6. The dry powder denitrification injection mechanism uses powdered or spherical polymeric solid denitrification agents to reduce NOx in the flue gas to N2 and H2O. Polymeric solid denitrification agents have significant advantages such as safe and convenient transportation and storage in solid powder form, no secondary pollution, and high denitrification rate. The optimal reaction temperature range is 800℃ to 900℃, and the denitrification efficiency can reach over 85%.

[0036] In some embodiments, such as Figure 1 and Figure 4 As shown, there is an angle β between the CO burner 8 and the inner wall of the central cylinder 7, and the angle β ranges from 20° to 60°.

[0037] Therefore, the included angle β between the CO burner 8 and the inner wall of the central cylinder 7 improves the carbon monoxide removal effect.

[0038] In some embodiments, such as Figure 1 As shown, the carbon monoxide and nitrogen oxide coupled removal system also includes a rapid exhaust device, which includes a rapid exhaust valve 2, a rapid exhaust chimney 1, and a transmission mechanism 3. The rapid exhaust chimney 1 is connected to the outlet flue 4, the rapid exhaust valve 2 is located on the pipeline of the rapid exhaust chimney 1, and the transmission mechanism 3 controls the opening and closing of the rapid exhaust valve 2.

[0039] Specifically, the transmission mechanism 3 can be pneumatic or electric. The transmission mechanism 3 controls the opening and closing of the emergency exhaust valve 2. When the pressure inside the central cylinder 7 is too high, it controls the opening of the emergency exhaust valve 2 to reduce the pressure inside the central cylinder 7 through the emergency exhaust chimney 1, thus ensuring equipment safety.

[0040] In some embodiments, a pressure measuring point is provided on the outlet flue 4, and the pressure measuring point is interlocked with the transmission mechanism 3.

[0041] Specifically, when the pressure is greater than 300Pa, the pressure measurement data is transmitted to the control system terminal, and the terminal controls the opening of the emergency exhaust valve. The emergency exhaust valve 2 is automatically opened under the drive of the transmission mechanism 3. The emergency exhaust chimney 1 can be set on the outlet flue 4 or on the upper cone 5.

[0042] Implementation Case 1:

[0043] The flue gas from the blast furnace in recycled copper smelting contains pollutants such as CO (≈38000ppm), NOx (≈400mg / Nm3), SO2, and dust. The flue gas temperature at the blast furnace outlet is approximately 350℃±50℃, and the flue gas volume is approximately ≈11800Nm3 / h.

[0044] The flue gas first undergoes pre-dust removal in a cyclone dust collector 17. The inner lining of the single-cylinder cyclone dust collector is 80mm thick high-strength refractory castable, with an inner diameter of φ1.6m. The flue gas that has undergone pre-dust removal in the cyclone dust collector 17 then enters the removal device 18.

[0045] Flue gas enters the central cylinder 7 through the inlet flue 11 at the bottom of the lower ash hopper 12 and moves upwards. Combustion air (≈2800 Nm3 / h) is injected into the central cylinder 7 through the annular duct 10 above the inlet flue 11 and 12 branch ducts 9, mixing with the flue gas and moving upwards together. The branch ducts 9 are arranged inclined along the inner wall of the central cylinder 7 at an angle α = 15°.

[0046] Two sets of CO burners 8 are arranged above the annular duct 10 to remove CO from the flue gas. Natural gas is used as fuel for the CO burners 8, and the gas flow rate of a single set of CO burners 8 is approximately 120 Nm3 / h. The CO burners 8 extend into the inner wall of the central cylinder 7 and are arranged symmetrically at an angle β = 30°.

[0047] Powdered polymer solid denitrification agent is injected into the interior of the central cylinder 7 through two dry powder denitrification injection channels 6, mixing with the flue gas and removing NOx from it. The two dry powder denitrification injection channels 6 are arranged symmetrically on the left and right sides. The PNCR injection channel 6 is located at the upper part of the central cylinder 7, and the temperature at the injection point is controlled at 850℃±50℃.

[0048] After denitrification, the flue gas is discharged from the outlet flue duct 4 through the upper cone 5 and enters the quench tower 19 to cool the flue gas to 200℃±20℃. After cooling, the flue gas enters the subsequent bag filter and desulfurization system. The specifications of the quench tower 19 are φ3500mm×15000mm (effective inner diameter and effective height), and the water spray volume is ~6t / h.

[0049] The emergency exhaust device is connected to the upper cone 5 and pressure interlocked with the outlet flue 4. When the pressure is greater than 300Pa, the emergency exhaust valve 2 will open automatically.

[0050] The outer diameter of the central cylinder 7 of the removal device 18 is φ4500mm, and the height of the central cylinder 7 is 7500mm. The residence time of the flue gas in the removal device 18 is ≈5s, and the outlet flue gas temperature is 800℃~850℃.

[0051] The central cylinder 7 of the removal device 18 is made of Q235 steel shell 13 (H0=10mm), lined with refractory material with a temperature resistance of >1000℃. From the outside to the inside, it consists of ceramic fiber felt 14 (thickness H1=50mm), lightweight castable 15 (thickness H2=100mm), and high-strength wear-resistant castable 16 (thickness H3=150mm). The overall thickness of the refractory material is H=300mm.

[0052] Implementation Case 2:

[0053] The side-blown furnace used to process copper-containing waste contains CO (≈35000ppm), NOx (≈350mg / Nm3), SO2, dust, and other pollutants in its flue gas. The outlet flue gas temperature of the side-blown furnace is approximately 370℃±30℃, and the flue gas volume is approximately ≈13200Nm3 / h.

[0054] The flue gas first undergoes pre-dust removal in a cyclone dust collector 17. The inner lining of the single-cylinder cyclone dust collector is 100mm thick high-strength refractory castable, with an inner diameter of φ1.8m. The flue gas that has undergone pre-dust removal in the cyclone dust collector 17 then enters the removal device 18.

[0055] Flue gas enters the central cylinder 7 through the inlet flue 11 at the bottom of the lower ash hopper 12 and moves upwards. Combustion air (≈2200 Nm3 / h) is injected into the interior of the central cylinder 7 through the annular duct 10 above the inlet flue 11 and eight branch ducts 9, mixing with the flue gas and moving upwards together. The branch ducts 9 are arranged obliquely along the inner wall of the central cylinder 7 at an angle α = 20°.

[0056] Two sets of CO burners 8 are arranged above the annular duct 10 to remove CO from the flue gas. The CO burners 8 are fueled by diesel oil, with a fuel consumption of approximately 200 kg / h. The CO burners 8 are symmetrically and inclinedly arranged inside the inner wall of the central cylinder 7, with an included angle β = 25°.

[0057] Spherical polymeric solid denitrification agent (particle size <3mm) is injected into the denitrification device 18 through two dry powder denitrification injection channels 6 to mix with the flue gas and remove NOx from the flue gas. The two dry powder denitrification injection channels 6 are arranged symmetrically on the left and right sides. The dry powder denitrification injection channels 6 are located on the upper part of the central cylinder 7, and the temperature of the injection point is controlled at ≈850℃.

[0058] After denitrification, the flue gas exits through the upper cone 5 and exits through the outlet flue 4. It then enters the quench tower 19 to cool the flue gas to approximately 200°C. After cooling, the flue gas enters the subsequent bag filter and desulfurization system. The quench tower 19 has specifications of φ3600mm × 15000mm (effective inner diameter and effective height) and a water spray rate of ~7t / h.

[0059] The emergency exhaust system is connected to the outlet flue 4 and is pressure interlocked with the outlet flue 4. When the pressure is greater than 300Pa, the emergency exhaust valve 2 will open automatically.

[0060] The outer diameter of the central cylinder 7 of the removal device 18 is φ4000mm, and the height of the central cylinder 7 is 10000mm. The residence time of the flue gas in the removal device is ≈5.5s, and the outlet flue gas temperature is ≈850℃.

[0061] The removal device 18 adopts a central cylindrical 7Q235 steel shell 13 (H0=12mm), lined with refractory material with a temperature resistance of >1000℃. From the outside to the inside, it consists of ceramic fiber felt 14 (thickness H1=60mm), lightweight castable 15 (thickness H2=120mm), and high-strength wear-resistant castable 16 (thickness H3=160mm). The overall thickness of the refractory material is H=340mm.

[0062] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0064] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0065] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0066] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0067] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A system for coupled removal of carbon monoxide and nitrogen oxides, characterized in that, The application relates to a combined flue gas denitration device. The combined flue gas denitration device comprises a cyclone dust collector, a coupling removal device and a quench tower. The coupling removal device comprises a central cylinder, a blower, a CO burner and a dry powder denitration injection mechanism. The top of the central cylinder is provided with an outlet flue, and the bottom of the central cylinder is provided with an inlet flue.

2. The carbon monoxide and nitrogen oxides coupled removal system of claim 1, wherein, The inlet flue is connected with the cyclone dust collector far from the end of the central cylinder.

3. The carbon monoxide and nitrogen oxides coupled removal system of claim 1, wherein, The dry powder denitration injection mechanism, the CO burner and the blower are sequentially arranged on the central cylinder between the inlet flue and the outlet flue in the height direction.

4. The carbon monoxide and nitrogen oxides coupled removal system of claim 3, wherein, The blower comprises a ring-shaped air duct.

5. The carbon monoxide and nitrogen oxides coupled removal system of claim 3, wherein, The ring-shaped air duct is located at the upper part of the inlet flue and sends air into the central cylinder.

6. The carbon monoxide and nitrogen oxides coupled removal system of claim 1, wherein, The CO burner is arranged above the ring-shaped air duct and is connected with the inside of the central cylinder.

7. The carbon monoxide and nitrogen oxides coupled removal system of claim 1, wherein, The dry powder denitration injection mechanism is arranged at the upper part of the CO burner and is connected with the inside of the central cylinder.

8. The carbon monoxide and nitrogen oxides coupled removal system of claim 7, wherein, The bottom of the central cylinder is provided with a lower ash bucket. The top of the central cylinder is provided with an upper cone. The outlet flue is connected with the top of the upper cone. The inlet flue is connected with the lower part of the central cylinder. The ring-shaped air duct is connected with the inside of the central cylinder through a plurality of branch air ducts. The branch air ducts are uniformly distributed on the side wall of the central cylinder. At least part of the branch air ducts enters the inside of the central cylinder. An included angle a exists between the branch air ducts and the inner wall of the central cylinder. The included angle a ranges from 10 DEG to 40 DEG. The branch air ducts are provided with control valves. The number of the branch air ducts is greater than or equal to 3. An included angle beta exists between the CO burner and the inner wall of the central cylinder. The included angle beta ranges from 20 DEG to 60 DEG. The combined flue gas denitration device further comprises an emergency exhaust device. The emergency exhaust device comprises an emergency exhaust valve, an emergency exhaust chimney and a transmission mechanism. The emergency exhaust chimney is connected with the outlet flue. The emergency exhaust valve is arranged on the pipeline of the emergency exhaust chimney. The transmission mechanism controls the opening and closing of the emergency exhaust valve. The outlet flue is provided with a pressure measuring point. The pressure measuring point is connected with the transmission mechanism for interlocking control.

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