Flue gas recirculation system for reducing nitrogen oxide of hot-blast stove prepared from pulverized coal

Abstract

The utility model relates to the technical field of pulverized coal preparation, in particular to a flue gas recirculation system for reducing nitrogen oxides in a hot blast stove prepared from pulverized coal, which comprises a coal mill mounting main body, a coal mill mounting main body and a coal mill mounting main body, a negative pressure detection assembly and a feeding pipe are fixedly connected to the side face of the coal mill mounting body, an adjusting bin is fixedly connected to one end of the feeding pipe, and a sliding baffle driven by a hydraulic oil cylinder is slidably inserted into one side of the adjusting bin; the coal mill has the beneficial effects that the allowable maximum value of the negative pressure in the coal mill mounting main body can be detected through the negative pressure detection assembly, the space in the coal mill mounting main body is smaller and smaller along with more feeding, and the negative pressure in the coal mill mounting main body is larger and larger, so that when the allowable maximum value of feeding is reached, the space in the coal mill mounting main body is smaller and smaller; the baffle can block the adjusting bin under pushing of the hydraulic oil cylinder so as to adjust the feeding speed, and therefore the situation that the motor is in an overload operation state all the time is avoided.

Description

Technical Field

[0001] The utility model relates to the field of pulverized coal preparation, in particular to a flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation. Background Technique

[0002] Energy is an important pillar of economic development. To meet the needs of rapid economic development, energy conservation and consumption reduction have become national policies. How to improve the thermal efficiency and reduce heat energy loss of widely used coal-fired boilers has also become an issue of widespread concern in the industry.

[0003] At present, a flue gas recirculation system for nitrogen oxides in a hot blast stove for pulverized coal preparation, which consists of a vertical coal mill, a pulverized coal boiler, a hot blast stove combustion chamber, a desulfurization chimney and other structures, can reduce the emission concentration of nitrogen oxides and achieve the effect of energy conservation and emission reduction.

[0004] However, in the prior art, the vertical coal mill may experience overgrinding when too much feed is supplied, causing the motor to operate under overload. If this continues for a long time, the motor may be burned out. Therefore, the utility model proposes a flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation to solve the above problems. Content of the Utility Model

[0005] The purpose of the utility model is to provide a flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation, so as to solve the problem in the above background technique that when too much feed is supplied to the vertical coal mill in the prior art, overgrinding may occur, causing the motor to operate under overload and possibly burning out the motor.

[0006] To achieve the above purpose, the utility model provides the following technical solution: A flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation, the flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation includes:

[0007] A coal mill installation main body, a negative pressure detection component and a feed pipe are fixedly connected to the side of the coal mill installation main body, one end of the feed pipe is fixedly connected to an adjustment bin, and a sliding baffle driven by a hydraulic cylinder is slidably inserted into one side of the adjustment bin;

[0008] The negative pressure detection component includes a communication pipe, the communication pipe is located on one side of the coal mill installation main body and is fixedly inserted into the coal mill installation main body, a communication groove for storing water and arranged in a "C" shape is opened at one end of the communication pipe, a floating plate is slidably connected to one side of the communication pipe, a fixed frame is fixedly connected to one end of the communication pipe, a fixed plate and a water-repellent breathable filling layer are fixedly connected to the inner side of the fixed frame, a plurality of air inlet holes are penetrated and opened on one side of the fixed plate, and a pressure sensor corresponding to the floating plate is fixedly connected.

[0009] Preferably, a support plate is fixedly connected to one side of the hydraulic cylinder, and one end of the support plate is fixedly connected to the feed pipe.

[0010] Preferably, a sliding groove for sliding the floating plate is provided at one end of the connecting pipe, and sliding blocks slidably connected to the sliding groove are fixedly connected to both ends of the floating plate.

[0011] Preferably, a protrusion is fixedly connected to one side of the floating plate, and the positions of the protrusion and the pressure sensor correspond to each other.

[0012] Preferably, a protective cover is fixedly connected to one side of the connecting pipe, the side surfaces of the protective cover are inclined, and a plurality of connecting plates are fixedly connected between the protective cover and the connecting pipe.

[0013] Preferably, the upper ends of the fixing frame and the hydrophobic air-permeable filling layer are both arranged obliquely, and one end of the connecting pipe is fixedly connected to a cover plate.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] The flue gas recirculation system for reducing nitrogen oxides in a hot blast furnace prepared by pulverized coal proposed in the utility model can detect the maximum allowable negative pressure in the coal mill installation body through a negative pressure detection component. Because as more material is fed, the space in the coal mill installation body will become less and less, and the negative pressure in the coal mill installation body will become greater and greater. When the maximum allowable feeding value is reached, the baffle will seal the adjustment bin under the push of the hydraulic cylinder to adjust the feed speed, thereby preventing the motor from being in an overloaded operating state all the time. This also solves the problem in the prior art that when the vertical coal mill is fed too much, saturation may occur, causing the motor to be in an overloaded operating state, which may lead to the motor burning. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional schematic diagram of the overall structure of the utility model;

[0017] Figure 2 This is a side schematic diagram of the negative pressure detection component structure of the utility model;

[0018] Figure 3 It is a side cross-sectional schematic diagram of the negative pressure detection component structure of the utility model;

[0019] Figure 4 This is an exploded view of the negative pressure detection component structure of the utility model.

[0020] In the figure: 1, coal mill installation body; 2, connecting pipe; 21, cover plate; 22, slideway; 23, fixing frame;

[0021] 3. Feed pipe; 4. Adjustment bin; 41. Baffle; 42. Hydraulic cylinder; 43. Support plate; 5. Floating plate;

[0022] 51. Bump; 52. Slide block; 6. Pressure sensor; 7. Fixed plate; 8. Hydrophobic and breathable filling layer; 9. Protective cover; 91. Connecting plate. Detailed implementation manner

[0023] In order to clearly and completely describe the purpose, technical solution of the present utility model and make the advantages more clear, the following further details the embodiments of the present utility model with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are part of the embodiments of the present utility model, rather than all the embodiments, and are only used to explain the embodiments of the present utility model, not to limit the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present utility model.

[0024] Embodiment 1, please refer to Figure 1-Figure 4 , the present utility model provides a technical solution: a flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation, and the flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation includes: a coal mill installation main body 1 and a negative pressure detection component.

[0025] Specifically, a negative pressure detection component and a feed pipe 3 are fixedly connected to the side of the coal mill installation main body 1, one end of the feed pipe 3 is fixedly connected to an adjustment bin 4, and a sliding baffle 41 driven by a hydraulic cylinder 42 is slidably inserted into one side of the adjustment bin 4;

[0026] Further, the negative pressure detection component includes a communication pipe 2. The communication pipe 2 is located on one side of the coal mill installation main body 1 and is fixedly inserted into the coal mill installation main body 1. A communication groove for storing water and arranged in a "C" shape is opened at one end of the communication pipe 2. A floating plate 5 is slidably connected to one side of the communication pipe 2. A fixed frame 23 is fixedly connected to one end of the communication pipe 2. A fixed plate 7 and a hydrophobic and breathable filling layer 8 are fixedly connected to the inner side of the fixed frame 23. A plurality of air inlet holes are penetrated through one side of the fixed plate 7 and a pressure sensor 6 corresponding to the floating plate 5 is fixedly connected. As more and more materials are transported into the coal mill installation main body 1 through the feed pipe 3, the negative pressure inside the coal mill installation main body 1 will gradually increase. At this time, under the action of the external atmospheric pressure, the end of the flowing water with both ends horizontal in the communication groove of the communication pipe 2 located in the inner cavity of the coal mill installation main body 1 will rise, thereby pushing the floating plate 5 to slide upward. Finally, the floating plate 5 will apply pressure to the pressure sensor 6. At this time, it means that the inner cavity of the coal mill installation main body 1 has reached the full grinding state. The hydraulic cylinder 42 will push the baffle 41 to block the adjustment bin 4 to adjust the feeding speed and avoid the motor being always in an overloaded state. The fixed plate 7 can support the hydrophobic and breathable filling layer 8, and the air inlet holes opened on the fixed plate 7 and the hydrophobic and breathable filling layer 8 can ensure that the internal air pressure can enter the communication pipe 2, thereby ensuring the generation of a pressure difference.

[0027] In order to facilitate the installation of the hydraulic cylinder 42, a support plate 43 is fixedly connected to one side of the hydraulic cylinder 42 of the present application, and one end of the support plate 43 is fixedly connected to the feed pipe 3, which can ensure that the hydraulic cylinder 42 has an installation platform, thereby ensuring that the hydraulic cylinder 42 can better drive the baffle 41 to slide.

[0028] In order to more accurately locate the trajectory of the floating plate 5 when it slides, a sliding groove 22 for the floating plate 5 to slide is opened at one end of the connecting pipe 2 of the present application, and sliders 52 slidably connected to the sliding groove 22 are fixedly connected at both ends of the floating plate 5. This can ensure that the rising trajectory of the floating plate 5 is fixed when it is pushed up by the water in the inner cavity of the connecting pipe 2, and ensure that the floating plate 5 will not tilt.

[0029] In order to better apply pressure to the pressure sensor 6, a protrusion 51 is fixedly connected to one side of the floating plate 5 of the present application. The positions of the protrusion 51 and the pressure sensor 6 correspond to each other. When the floating plate 5 floats up, it will also slide upward with the protrusion 51, eventually causing the protrusion 51 to contact with the pressure sensor 6 and apply pressure to the pressure sensor 6.

[0030] In order to protect the connecting pipe 2, a protective cover 9 is fixedly connected to one side of the connecting pipe 2 of the present application. The sides of the protective cover 9 are all inclined. A plurality of connecting plates 91 are fixedly connected between the protective cover 9 and the connecting pipe 2. The protective cover 9 can block powders and the like to improve the safety of the connecting pipe 2. The inclined sides of the protective cover 9 can ensure that powders will not accumulate on the protective cover 9.

[0031] In order to further improve the feasibility of the connecting tube 2, the upper ends of the fixing frame 23 and the hydrophobic breathable filling layer 8 of the present application are both arranged at an angle, which ensures that some powder that falls onto the surface of the hydrophobic breathable filling layer 8 will not accumulate on the surface of the fixing frame 23 and the hydrophobic breathable filling layer 8. One end of the connecting tube 2 is fixedly connected to a cover plate 21, which can block external debris to avoid affecting negative pressure detection.

[0032] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation, characterized in that: The flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation includes: A coal mill installation main body (1), a negative pressure detection component and a feed pipe (3) are fixedly connected to the side of the coal mill installation main body (1), one end of the feed pipe (3) is fixedly connected to a regulating bin (4), and a sliding baffle (41) driven by a hydraulic cylinder (42) is slidably inserted into one side of the regulating bin (4); The negative pressure detection component includes a connecting pipe (2), the connecting pipe (2) is located on one side of the coal mill installation main body (1) and is fixedly inserted with the coal mill installation main body (1), a connecting groove for storing water and arranged in a "C" shape is opened at one end of the connecting pipe (2), a floating plate (5) is slidably connected to one side of the connecting pipe (2), a fixing frame (23) is fixedly connected to one end of the connecting pipe (2), a fixing plate (7) and a water-repellent breathable filling layer (8) are fixedly connected to the inner side of the fixing frame (23), a plurality of air inlet holes are penetrated and opened on one side of the fixing plate (7) and a pressure sensor (6) corresponding to the floating plate (5) is fixedly connected.

2. The flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation according to claim 1, characterized in that: One side of the hydraulic cylinder (42) is fixedly connected with a support plate (43), and one end of the support plate (43) is fixedly connected with the feed pipe (3).

3. The flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation according to claim 1, characterized in that: A sliding groove (22) for the floating plate (5) to slide is opened at one end of the connecting pipe (2), and sliding blocks (52) slidably connected with the sliding groove (22) are fixedly connected to both ends of the floating plate (5).

4. The flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation according to claim 3, characterized in that: A convex block (51) is fixedly connected to one side of the floating plate (5), and the position of the convex block (51) corresponds to that of the pressure sensor (6).

5. The flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation according to claim 3, characterized in that: A protective cover (9) is fixedly connected to one side of the connecting pipe (2), the sides of the protective cover (9) are all inclined, and a plurality of connecting plates (91) are fixedly connected between the protective cover (9) and the connecting pipe (2).

6. The flue gas recirculation system for reducing nitrogen oxides in a hot blast stove for pulverized coal preparation according to claim 1, characterized in that: The upper ends of the fixing frame (23) and the water-repellent breathable filling layer (8) are both inclined, and a cover plate (21) is fixedly connected to one end of the connecting pipe (2).

Images