A metallurgical waste gas denitrification process and denitrification device

Abstract

The present invention belongs to the technical field of waste gas treatment, and specifically, is a metallurgical waste gas denitration process and a denitration device, comprising a denitration reactor; a transfer box is fixedly connected to the outside of the denitration reactor; an injection frame is fixedly connected to the outside of the transfer box and located inside the denitration reactor, and a penetration hole is opened on the top of the injection frame; ammonia is sprayed by atomizing a spray gun to react with the waste gas discharged into the denitration reactor through the guide tube, thereby improving the effect of the waste gas denitration reaction, using a filter screen plate to guide impurities generated by the reaction, and the impurities are collected in a collection tank for temporary storage, and a servo motor output end is used to drive a plurality of No. 1 reduction filter plates to rotate, and the plurality of No. 1 reduction filter plates can fully mix with the waste gas for secondary denitration reaction, thereby improving the denitration effect of the waste gas, relying on the filter layer plate to filter the impurities in the waste gas, reducing the residual impurities in the waste gas, cooperating with the No. 2 reduction filter plate to finally denitrate the waste gas, and ensuring the denitration effect of the waste gas.

Description

Technical Field

[0001] The invention belongs to the technical field of waste gas treatment, and in particular relates to a metallurgical waste gas denitration process and a denitration device. Background Art

[0002] Metallurgical waste gas is harmful waste gas produced in the metallurgical industry. Metallurgical waste gas treatment is to remove harmful gases, particulate matter and odorous substances in the waste gas to meet the emission standards. The denitrification process in metallurgical waste gas treatment is also one of the important treatment steps.

[0003] A patent application with publication number CN105944562A discloses a denitrification device for ship exhaust gas, including an air bleed pipe, a fuel tank, a burner, an exhaust gas inlet pipe, a combustion chamber, a spray gun, a reactor and an exhaust gas outlet pipe. The air bleed pipe and the fuel tank are connected to the combustion chamber through the burner, the exhaust gas inlet pipe is connected to the combustion chamber, and the spray gun is located in the combustion chamber. This application prevents the exhaust gas flow from affecting the flame in the inner combustion chamber through the side wall of the inner combustion chamber, thereby stabilizing the flame in the combustion chamber.

[0004] The above-mentioned denitrification device divides the combustion chamber into an inner combustion chamber and an outer combustion chamber to stabilize the flame in the combustion chamber and improve the combustion efficiency. However, during the reaction process of the current denitrification device, due to the fast flow rate of the flue gas, the exhaust gas is difficult to fully contact and mix during the reaction process, thereby affecting the denitrification effect of the exhaust gas.

[0005] To this end, the present invention provides a metallurgical waste gas denitration process and a denitration device. Summary of the invention

[0006] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0007] The technical solution adopted by the present invention to solve its technical problems is: a metallurgical waste gas denitrification device described in the present invention includes a denitrification reactor; a transfer box is fixedly connected to the outside of the denitrification reactor; an injection rack is fixedly connected to the outside of the transfer box and located inside the denitrification reactor, and a through hole is opened at the top of the injection rack; a spray gun is fixedly connected to the bottom end of the injection rack, and the spray gun is connected to the transfer box through the injection rack; a guide tube is fixedly connected to the bottom end of the denitrification reactor and located below the spray gun, and the vent at the top of the guide tube is close to the output end of the spray gun; a matching component is arranged inside the denitrification reactor, and the matching component is used to improve the effect of waste gas denitrification.

[0008] Preferably, a filter screen is fixedly connected inside the denitration reactor and located between the spray gun and the guide tube, and the filter screen is arranged at an angle; a collecting groove is provided inside the denitration reactor and close to the filter screen, and the collecting groove is connected to the end face of the filter screen.

[0009] Preferably, the matching components include a servo motor, a connecting rod and a No. 1 reduction filter plate; the servo motor is fixedly connected to the top of the denitrification reactor; the connecting rod is fixedly connected to the output end of the servo motor; a plurality of No. 1 reduction filter plates are fixedly connected to the outside of the connecting rod, and the plurality of No. 1 reduction filter plates are arranged in an upper and lower surrounding layer.

[0010] Preferably, a No. 2 reduction filter plate is fixedly connected inside the denitration reactor and below the No. 1 reduction filter plate; a cylinder is fixedly connected to the top of the No. 2 reduction filter plate, and the cylinder surrounds multiple No. 1 reduction filter plates; a filter layer plate is fixedly connected inside the denitration reactor and above the injection rack.

[0011] Preferably, a No. 1 bevel gear is fixedly connected to the outside of the connecting rod; a fixed frame is fixedly connected to the inside of the denitrification reactor; a rotating rod is rotatably connected to the inside of the fixed frame; a scraper is fixedly connected to the outside of the rotating rod, and the scraper fits the outside of the filter plate; a No. 2 bevel gear is fixedly connected to the end of the rotating rod away from the scraper, and the No. 2 bevel gear is meshed with the No. 1 bevel gear.

[0012] Preferably, a No. 1 exhaust fan blade is fixedly connected to the outside of the connecting rod; and a No. 2 exhaust fan blade is fixedly connected to the outside of the rotating rod and at one end away from the No. 2 bevel gear.

[0013] Preferably, a water pump No. 1 is installed inside the denitrification reactor and below the No. 2 reduction filter plate; the output end of the water pump No. 1 is fixedly connected to a pipe No. 1, and the end of the pipe No. 1 away from the water pump No. 1 is connected to a fixed frame; a plurality of flow holes are provided on the outside of the rotating rod and close to the fixed frame; a water spray hole is provided on the outside of the scraper, and the scraper can be connected to the water pump No. 1 through the rotating rod and the fixed frame.

[0014] Preferably, a No. 2 water pump is installed outside the guide tube; a No. 2 pipe is fixedly connected to the output end of the No. 2 water pump, and one end of the No. 2 pipe away from the No. 2 water pump is fixedly connected to a cylinder; a plurality of spray holes are opened on the inner wall of the cylinder.

[0015] A metallurgical waste gas denitration process, which uses the above-mentioned denitration device for processing, is characterized in that the process steps are as follows:

[0016] S1: Transportation and storage of reducing agent: The reducing agent is transported in the form of ammonia gas in a filling truck; liquid ammonia needs to be evaporated and gasified by an evaporator before being injected into the flue gas of the SCR system; liquid ammonia is stored in ammonia tanks in liquid form for use;

[0017] S2: Injection and premixing of ammonia water: ammonia water is atomized by two fluids, and sprayed into the reflowing flue gas by a spray gun under the atomization effect of compressed air. Ammonia water is rapidly pyrolyzed into ammonia gas and water, and after being fully mixed, hot flue gas uniformly mixed with ammonia gas is formed;

[0018] S3: Reaction in SCR reactor: In the SCR catalytic reactor, after the reducing agent is fully mixed, the reducing agent and the flue gas react under the action of the catalyst to remove NOx.

[0019] Preferably, the spray gun atomization in S2 adopts compressed air cooling and atomization, selects a temperature window to spray the reducing agent, and adopts an SCR spray gun to spray the ammonia solution into the flue for reduction reaction to ensure the penetration depth and coverage.

[0020] The beneficial effects of the present invention are as follows:

[0021] 1. The metallurgical waste gas denitrification process and denitrification device described in the present invention, through the spray gun atomization spray ammonia and the waste gas discharged into the denitrification reactor guided by the guide tube, the denitrification effect of the waste gas is improved, the impurities generated by the reaction are guided by the filter screen plate, and the impurities are temporarily stored in the collection tank, and the output end of the servo motor is used to drive multiple No. 1 reduction filter plates to rotate. The multiple No. 1 reduction filter plates can fully mix with the waste gas for secondary denitrification reaction, thereby improving the denitrification effect of the waste gas, relying on the filter layer plate to filter the impurities in the waste gas, reducing the residual impurities in the waste gas, and cooperating with the No. 2 reduction filter plate to finally denitrify the waste gas, thereby ensuring the denitrification effect of the waste gas.

[0022] 2. The metallurgical waste gas denitrification process and denitrification device described in the present invention scrapes the surface of the filter plate by a scraper to maintain the filtering effect of the filter plate on the waste gas, utilizes the No. 1 exhaust fan blade and the No. 2 exhaust fan blade to rotate with the output end of the servo motor to accelerate the flow speed of the waste gas inside the denitrification reactor and improve the efficiency of waste gas denitrification, relies on the No. 1 water pump to extract the water produced by the reaction and return it, and sprays water from the scraper to wash the surface of the filter plate, so as to recycle the reaction water while maintaining the filtering effect of the filter plate, utilizes the No. 2 water pump to extract the excessive sprayed ammonia water, sends it to the inside of the cylinder and sprays it onto multiple No. 1 reduction filter plates, so as to maintain the denitrification effect of multiple No. 1 reduction filter plates on the waste gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] Figure 1 is a stereogram of the present invention;

[0025] Figure 2 It is a partial structural sectional view of the destocking body in the present invention;

[0026] Figure 3 It is a structural schematic diagram of the rotating rod in the present invention;

[0027] Figure 4 It is a schematic diagram of the structure of the No. 1 reduction filter plate in the present invention;

[0028] Figure 5 It is a flow chart of the metallurgical waste gas denitration process in the present invention.

[0029] In the figure: 1. Denitration reactor; 11. Transfer box; 12. Injection rack; 13. Spray gun; 14. Guide tube; 2. Filter screen plate; 21. Collecting tank; 3. Servo motor; 31. Connecting rod; 32. No. 1 reduction filter plate; 4. Cylinder; 41. No. 2 reduction filter plate; 42. Filter layer plate; 5. No. 1 bevel gear; 51. Fixed rack; 52. Rotating rod; 53. Scraper; 54. No. 2 bevel gear; 6. No. 1 exhaust fan blade; 61. No. 2 exhaust fan blade; 7. No. 1 water pump; 71. No. 1 pipe; 72. Flow hole; 8. No. 2 water pump; 81. No. 2 pipe; 82. Spray hole. DETAILED DESCRIPTION

[0030] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0031] like Figure 1 and Figure 2 As shown, a metallurgical waste gas denitration device according to an embodiment of the present invention comprises a denitration reactor 1; a transfer box 11 is fixedly connected to the outside of the denitration reactor 1; an injection frame 12 is fixedly connected to the outside of the transfer box 11 and located inside the denitration reactor 1, and a through hole is provided at the top of the injection frame 12; a spray gun 13 is fixedly connected to the bottom end of the injection frame 12, and the spray gun 13 is connected to the transfer box 11 through the injection frame 12; a guide tube 14 is fixedly connected to the bottom end of the denitration reactor 1 and located below the spray gun 13, and the vent at the top of the guide tube 14 is close to the output end of the spray gun 13; the interior of the denitration reactor 1 is provided with a matching The components are used to improve the effect of denitration of exhaust gas; when denitration of exhaust gas generated by the metallurgical industry, the transfer box 11 is first connected to the ammonia tank, a small amount of ammonia is temporarily stored inside the transfer box 11, the guide tube 14 at the bottom end of the denitration reactor 1 is connected to the exhaust pipe, and the exhaust gas is discharged into the interior of the denitration reactor 1 from the guide tube 14. At this time, the spray gun 13 at the bottom end of the injection frame 12 draws ammonia for atomization and injection. Since the vent of the guide tube 14 is close to the output end of the spray gun 13, the ammonia can be mixed with the exhaust gas during atomization and injection. The mixed gas passes through the penetration hole directly to the matching component for secondary mixed catalytic reduction, thereby improving the effect of denitration of exhaust gas.

[0032] A filter screen plate 2 is fixedly connected inside the denitration reactor 1 and located between the spray gun 13 and the guide tube 14, and the filter screen plate 2 is inclined; a collecting tank 21 is opened inside the denitration reactor 1 and close to the filter screen plate 2, and the collecting tank 21 is connected to the end surface of the filter screen plate 2; when denitrifying metallurgical waste gas, since the waste gas contains harmful gases, particulate matter and malodorous substances, and the high-temperature flue gas is transported upward to react with the downwardly sprayed reducing agent in a counter-contact manner, particulate impurities are easily generated in the process, and the filter screen plate 2 is fixed between the spray gun 13 and the guide tube 14. After the waste gas passes through the filter screen plate 2, it is mixed with ammonia, and the particulate impurities generated by the reaction will fall on the filter screen plate 2, and slide along the inclined surface of the filter screen plate 2 to be collected in the collecting tank 21, thereby collecting the reaction impurities.

[0033] like Figures 1 to 4 As shown, the matching components include a servo motor 3, a connecting rod 31 and a No. 1 reduction filter plate 32; the servo motor 3 is fixedly connected to the top of the denitration reactor 1; the connecting rod 31 is fixedly connected to the output end of the servo motor 3; multiple No. 1 reduction filter plates 32 are fixedly connected to the outside of the connecting rod 31, and multiple No. 1 reduction filter plates 32 are arranged in an upper and lower surrounding layer; when the metallurgical waste gas is mixed with ammonia sprayed by the spray gun 13, the flue gas directly reaches the multiple No. 1 reduction filter plates 32, and the output end of the servo motor 3 drives the connecting rod 31 to rotate, and synchronously drives the multiple No. 1 reduction filter plates 32 to rotate. The multiple No. 1 reduction filter plates 32 contain ammonia, and the multiple No. 1 reduction filter plates 32 fully react with the passing flue gas for secondary mixing, thereby improving the effect of waste gas denitration, and the rotation of the multiple No. 1 reduction filter plates 32 can accelerate the gas flow speed inside the denitration reactor 1, thereby improving the efficiency of waste gas denitration.

[0034] A No. 2 reduction filter plate 41 is fixedly connected inside the denitration reactor 1 and below the No. 1 reduction filter plate 32; a cylinder 4 is fixedly connected to the top of the No. 2 reduction filter plate 41, and the cylinder 4 surrounds multiple No. 1 reduction filter plates 32; a filter layer plate 42 is fixedly connected inside the denitration reactor 1 and located above the injection rack 12; when the exhaust gas flows inside the denitration reactor 1, the filter layer plate 42 can filter impurities in the exhaust gas and reduce the residual impurities in the exhaust gas. After the exhaust gas passes through the filter layer plate 42 and reaches the cylinder 4, the exhaust gas is denitrated by multiple No. 1 reduction filter plates 32, and finally the exhaust gas is subjected to a final mixed catalytic reaction by the No. 2 reduction filter plate 41, thereby improving the denitration effect of the exhaust gas.

[0035] like Figures 1 to 4As shown, the outside of the connecting rod 31 is fixedly connected to the first bevel gear 5; the inside of the denitration reactor 1 is fixedly connected to a fixing frame 51; the inside of the fixing frame 51 is rotatably connected to a rotating rod 52; the outside of the rotating rod 52 is fixedly connected to a scraper 53, and the scraper 53 is attached to the outside of the filter layer plate 42; the end of the rotating rod 52 away from the scraper 53 is fixedly connected to the second bevel gear 54, and the second bevel gear 54 is meshed with the first bevel gear 5; when the filter layer plate 42 is exposed to impurities in the exhaust gas for a long time, the second bevel gear 54 is meshed with the first bevel gear 5. After the mass is filtered, the residual impurities on the surface of the filter plate 42 affect the filtering effect. The scraper 53 is attached to the filtering surface of the filter plate 42, and the servo motor 3 drives the first bevel gear 5 to rotate. The first bevel gear 5 and the second bevel gear 54 are meshed and rotated with each other, and the second bevel gear 54 drives the scraper 53 at the other end of the rotating rod 52 to rotate. The scraper 53 scrapes and cleans the filtering surface of the filter plate 42, and the cleaned impurities finally fall into the inside of the collecting tank 21 for collection, so as to maintain the filtering effect of the filter plate 42.

[0036] The outside of the connecting rod 31 is fixedly connected with a No. 1 exhaust fan blade 6; the outside of the rotating rod 52 and one end away from the No. 2 bevel gear 54 is fixedly connected with a No. 2 exhaust fan blade 61; when treating metallurgical waste gas, if the flow speed of the flue gas inside the denitrification reactor 1 is slow, which is easy to affect the efficiency of the waste gas reaction denitrification, the output end of the servo motor 3 is used to drive the connecting rod 31 to rotate, and the No. 1 exhaust fan blade 6 on the outside of the connecting rod 31 rotates accordingly to exhaust air, and cooperates with the No. 2 exhaust fan blade 61 at one end of the rotating rod 52 to rotate accordingly to exhaust air, thereby accelerating the flow speed of the waste gas inside the denitrification reactor 1, and through multiple reaction denitrification, the denitrification efficiency is accelerated while ensuring the waste gas denitrification effect.

[0037] like Figures 1 to 3 As shown, a water pump 7 is installed inside the denitration reactor 1 and below the second reduction filter plate 41; a pipe 71 is fixedly connected to the output end of the water pump 7, and the end of the pipe 71 away from the water pump 7 is connected to the fixing frame 51; a plurality of flow holes 72 are provided outside the rotating rod 52 and near the fixing frame 51; a water spray hole is provided outside the scraper 53, and the scraper 53 can be connected to the water pump 7 through the rotating rod 52 and the fixing frame 51; after the exhaust gas is denitrated, nitrogen and Water and nitrogen are discharged from the outlet connecting pipe of the denitration reactor 1, and the water falls on the No. 1 water pump 7 for temporary storage. In order to maintain the filtering effect on the filter plate 42, the No. 1 water pump 7 is used to extract the water produced after the reaction, and the No. 1 pipe 71 is used to pass the water through the flow fixing frame 51 and the rotating rod 52. Finally, the water is sent to the scraper 53 and sprayed obliquely on the filter plate 42. With the rotation of the scraper 53, the surface of the filter plate 42 can be evenly rinsed and cleaned, and the reaction water can be recycled while maintaining the stability of the filter plate 42 in filtering the waste gas impurities.

[0038] A No. 2 water pump 8 is installed on the outside of the guide tube 14; a No. 2 pipe 81 is fixedly connected to the output end of the No. 2 water pump 8, and the end of the No. 2 pipe 81 away from the No. 2 water pump 8 is fixedly connected to the cylinder 4; a plurality of spray holes 82 are opened on the inner wall of the cylinder 4; when the spray gun 13 atomizes and sprays ammonia mixed with exhaust gas for reaction, since the amount of exhaust gas entering the denitration reactor 1 is not stable, if the ammonia injection amount is too large, part of the ammonia is easily wasted. The No. 2 water pump 8 is installed on the outside of the guide tube 14 and placed below the spray gun 13. Part of the unreacted ammonia water can be collected above the No. 2 water pump 8. The ammonia water is extracted by the No. 2 water pump 8 and sent to the inside of the cylinder 4 through the No. 2 pipe 81, and finally sprayed onto the plurality of No. 1 reduction filter plates 32 through the plurality of spray holes 82, thereby maintaining the residual ammonia on the No. 1 reduction filter plate 32 and maintaining the effect of the plurality of No. 1 reduction filter plates 32 on the exhaust gas denitration reaction.

[0039] like Figure 5 As shown, a metallurgical waste gas denitrification process, which uses the above-mentioned denitrification device for processing, is characterized in that the process steps are as follows:

[0040] S1: Transportation and storage of reducing agent: The reducing agent is transported in the form of ammonia gas in a filling truck; liquid ammonia needs to be evaporated and gasified by an evaporator before being injected into the flue gas of the SCR system; liquid ammonia is stored in ammonia tanks in liquid form for use;

[0041] S2: Injection and premixing of ammonia water: ammonia water is atomized by two fluids, and under the atomization effect of compressed air, it is sprayed into the reflowing flue gas by a spray gun 13, and the ammonia water is rapidly pyrolyzed into ammonia gas and water, and after being fully mixed, hot flue gas uniformly mixed with ammonia gas is formed;

[0042] S3: Reaction in SCR reactor: In the SCR catalytic reactor, after the reducing agent is fully mixed, the reducing agent and the flue gas react under the action of the catalyst to remove NOx.

[0043] The spray gun 13 in S2 is atomized by compressed air cooling and atomization, and the reducing agent is sprayed in the selected temperature window. The ammonia solution is sprayed into the flue by the SCR spray gun for reduction reaction to ensure the penetration depth and coverage.

[0044] During the working process, when denitrifying the waste gas generated by the metallurgical industry, the transfer box 11 is first connected to the ammonia tank, a small amount of ammonia is temporarily stored inside the transfer box 11, and the guide tube 14 at the bottom of the denitrification reactor 1 is connected to the waste gas pipe, and the waste gas is discharged into the denitrification reactor 1 from the guide tube 14. At this time, the spray gun 13 at the bottom of the injection frame 12 extracts ammonia for atomization and injection. Since the vent of the guide tube 14 is close to the output end of the spray gun 13, the ammonia can be mixed with the waste gas during atomization and injection. The mixed gas passes through the penetration hole directly to the matching component for secondary mixed catalytic reduction. And improve the effect of denitrification of exhaust gas; when denitrifying metallurgical exhaust gas, since the exhaust gas contains harmful gases, particulate matter and malodorous substances, and adopts the method of conveying high-temperature flue gas upward and reacting with the downward spraying reducing agent in a counter-contact manner, particulate impurities are easily generated in the process, and the filter screen plate 2 is fixed between the spray gun 13 and the guide tube 14. After the exhaust gas passes through the filter screen plate 2, it mixes with ammonia, and the particulate impurities generated by the reaction will fall on the filter screen plate 2, and slide along the inclined surface of the filter screen plate 2 to be collected in the collection tank 21, which plays a role in collecting the reaction impurities;

[0045] After the metallurgical waste gas is mixed with ammonia sprayed by the spray gun 13, the flue gas directly reaches the multiple No. 1 reduction filter plates 32, and the output end of the servo motor 3 drives the connecting rod 31 to rotate, and synchronously drives the multiple No. 1 reduction filter plates 32 to rotate. The multiple No. 1 reduction filter plates 32 contain ammonia, and the multiple No. 1 reduction filter plates 32 fully react with the passing flue gas for secondary mixing, thereby improving the effect of waste gas denitrification, and the rotation of the multiple No. 1 reduction filter plates 32 can accelerate the gas flow rate inside the denitrification reactor 1, and improve the efficiency of waste gas denitrification; when the waste gas flows inside the denitrification reactor 1, the filter layer plate 42 can filter the impurities in the waste gas and reduce the residual impurities in the waste gas. After the waste gas passes through the filter layer plate 42 and reaches the cylinder 4, the waste gas is denitrified by the multiple No. 1 reduction filter plates 32, and finally the waste gas is finally mixed and catalytically reacted by the No. 2 reduction filter plate 41, thereby improving the effect of waste gas denitrification; after the filter layer plate 42 has filtered the impurities in the waste gas for a long time, the surface residue of the filter layer plate 42 The impurities left behind affect the filtering effect. The scraper 53 is attached to the filtering surface of the filter layer plate 42, and the servo motor 3 drives the first bevel gear 5 to rotate. The first bevel gear 5 and the second bevel gear 54 mesh with each other and rotate. The second bevel gear 54 drives the scraper 53 at the other end of the rotating rod 52 to rotate. The scraper 53 scrapes and cleans the filtering surface of the filter layer plate 42, and the impurities that fall down finally fall into the collection tank 21 for collection, so as to maintain the filtering effect of the filter layer plate 42. When treating metallurgical waste gas, if the flow speed of the flue gas inside the denitration reactor 1 is slow, it is easy to affect the efficiency of the waste gas reaction denitration. The output end of the servo motor 3 is used to drive the connecting rod 31 to rotate, and the first exhaust fan blade 6 outside the connecting rod 31 rotates to exhaust air, and cooperates with the second exhaust fan blade 61 at one end of the rotating rod 52 to rotate to exhaust air, so as to accelerate the flow speed of the waste gas inside the denitration reactor 1, and accelerate the denitration efficiency while ensuring the denitration effect of the waste gas through multiple reactions.

[0046] After the exhaust gas is denitrated, nitrogen and water are generated. The nitrogen is discharged from the outlet connecting pipe of the denitration reactor 1, and the water falls on the No. 1 water pump 7 for temporary storage. In order to maintain the filtering effect of the filter layer plate 42, the No. 1 water pump 7 is used to extract the water generated after the reaction, and the No. 1 pipe 71 is used to pass the water through the flow fixing frame 51 and the rotating rod 52. Finally, the water is sent to the scraper 53 and sprayed obliquely on the filter layer plate 42. With the rotation of the scraper 53, the surface of the filter layer plate 42 can be evenly rinsed and cleaned, and the reaction water is recycled while maintaining the stability of the filter layer plate 42 in filtering the exhaust gas impurities;

[0047] When the spray gun 13 atomizes and sprays ammonia mixed with exhaust gas to react, the amount of exhaust gas entering the denitration reactor 1 is not stable. If the amount of ammonia sprayed is too large, some ammonia will be easily wasted. The No. 2 water pump 8 is installed on the outside of the guide tube 14 and placed below the spray gun 13. The top of the No. 2 water pump 8 can collect some unreacted ammonia water, and the ammonia water is extracted by the No. 2 water pump 8 and sent to the inside of the cylinder 4 through the No. 2 pipe 81. Finally, it is sprayed onto the multiple No. 1 reduction filter plates 32 at multiple spray holes 82, thereby maintaining the residual ammonia on the No. 1 reduction filter plate 32 and maintaining the effect of the multiple No. 1 reduction filter plates 32 on the exhaust gas denitration reaction.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A metallurgical waste gas denitrification device, characterized in that: The invention comprises a denitration reactor (1); a transfer box (11) is fixedly connected to the outside of the denitration reactor (1); an injection frame (12) is fixedly connected to the outside of the transfer box (11) and located inside the denitration reactor (1), and a through hole is provided at the top of the injection frame (12); a spray gun (13) is fixedly connected to the bottom end of the injection frame (12), and the spray gun (13) and the transfer box (11) are connected through the injection frame (12); a guide tube (14) is fixedly connected to the bottom end of the denitration reactor (1) and located below the spray gun (13), and a vent at the top end of the guide tube (14) is close to the output end of the spray gun (13); a matching component is arranged inside the denitration reactor (1), and the matching component is used to improve the denitration effect of the exhaust gas; A filter screen plate (2) is fixedly connected inside the denitration reactor (1) and between the spray gun (13) and the guide tube (14), and the filter screen plate (2) is arranged at an angle; a collecting groove (21) is provided inside the denitration reactor (1) and close to the filter screen plate (2), and the collecting groove (21) is connected to the end surface of the filter screen plate (2); The matching assembly comprises a servo motor (3), a connecting rod (31) and a first reduction filter plate (32); the servo motor (3) is fixedly connected to the top of the denitration reactor (1); the connecting rod (31) is fixedly connected to the output end of the servo motor (3); a plurality of the first reduction filter plates (32) are fixedly connected to the outside of the connecting rod (31), and the plurality of the first reduction filter plates (32) are arranged in a layered manner in an upper and lower surrounding manner; A No. 2 reduction filter plate (41) is fixedly connected inside the denitration reactor (1) and below the No. 1 reduction filter plate (32); a cylinder (4) is fixedly connected to the top of the No. 2 reduction filter plate (41), and the cylinder (4) surrounds a plurality of No. 1 reduction filter plates (32); and a filter layer plate (42) is fixedly connected inside the denitration reactor (1) and above the injection frame (12).

2. A metallurgical waste gas denitrification device according to claim 1, characterized in that: The outside of the connecting rod (31) is fixedly connected to a first bevel gear (5); the inside of the denitration reactor (1) is fixedly connected to a fixing frame (51); the inside of the fixing frame (51) is rotatably connected to a rotating rod (52); the outside of the rotating rod (52) is fixedly connected to a scraper (53), and the scraper (53) fits the outside of the filter plate (42); the end of the rotating rod (52) away from the scraper (53) is fixedly connected to a second bevel gear (54), and the second bevel gear (54) and the first bevel gear (5) are meshed with each other.

3. A metallurgical waste gas denitrification device according to claim 2, characterized in that: The outside of the connecting rod (31) is fixedly connected to a first exhaust fan blade (6); the outside of the rotating rod (52) and one end away from the second bevel gear (54) is fixedly connected to a second exhaust fan blade (61).

4. A metallurgical waste gas denitrification device according to claim 2, characterized in that: A No. 1 water pump (7) is installed inside the denitration reactor (1) and below the No. 2 reduction filter plate (41); the output end of the No. 1 water pump (7) is fixedly connected to a No. 1 pipe (71), and one end of the No. 1 pipe (71) away from the No. 1 water pump (7) is connected to a fixed frame (51); a plurality of flow holes (72) are provided outside the rotating rod (52) and near the fixed frame (51); a water spray hole is provided outside the scraper (53), and the scraper (53) can be connected to the No. 1 water pump (7) through the rotating rod (52) and the fixed frame (51).

5. The metallurgical waste gas denitrification device according to claim 1, characterized in that: A No. 2 water pump (8) is installed outside the guide tube (14); a No. 2 pipe (81) is fixedly connected to the output end of the No. 2 water pump (8), and an end of the No. 2 pipe (81) away from the No. 2 water pump (8) is fixedly connected to the cylinder (4); and a plurality of spray holes (82) are provided on the inner wall of the cylinder (4).

6. A process for denitrification of metallurgical waste gas, which is processed by using the denitrification device according to any one of claims 1 to 5, characterized in that: The process steps are as follows: S1: Transportation and storage of reducing agent: The reducing agent is transported in the form of ammonia gas in a filling truck; liquid ammonia needs to be evaporated and gasified by an evaporator before being injected into the flue gas of the SCR system; liquid ammonia is stored in ammonia tanks in liquid form for use; S2: Injection and premixing of ammonia water: ammonia water is atomized by two fluids, and under the atomization effect of compressed air, it is sprayed into the reflowing flue gas by using a spray gun (13), and the ammonia water is rapidly pyrolyzed into ammonia gas and water, and after being fully mixed, hot flue gas uniformly mixed with ammonia gas is formed; S3: Reaction in SCR reactor: In the SCR catalytic reactor, after the reducing agent is fully mixed, the reducing agent and the flue gas react under the action of the catalyst to remove NOx.

7. A metallurgical waste gas denitrification process according to claim 6, characterized in that: The spray gun (13) in S2 is atomized by compressed air cooling and atomization, and the temperature window is selected to spray the reducing agent. The spray gun (13) is used to spray the ammonia solution into the flue for reduction reaction, thereby ensuring the penetration depth and coverage.

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