Dry dust removal system for discharging of hydrogen-based shaft furnace

Abstract

The utility model belongs to the technical field of environmental protection and dust removal, and relates to a dry dust removal system for discharging of a hydrogen-based shaft furnace, which comprises a dust removal cover, a spark catcher, a spark arrester and a bag-type dust remover which are sequentially connected through a flue gas pipeline along the flowing direction of discharging of the hydrogen-based shaft furnace, and the dust removal cover is connected with a discharging port of the hydrogen-based shaft furnace; a first-stage spark detection system is arranged between the spark catcher and the spark arrester, and the spark arrester is connected with a nitrogen system, so that nitrogen is sprayed into the spark arrester through the nitrogen system when the first-stage spark detection system detects sparks. The utility model solves the flammable and explosive problem of direct reduction iron flue gas in dry dedusting, realizes the dry dedusting of the discharged material of the hydrogen-based shaft furnace, has the advantages of no water consumption, no wastewater pollution, high dedusting efficiency and good treatment effect, and meets the ultra-low emission requirement of the national iron and steel industry.

Description

Technical Field

[0001] The utility model belongs to the technical field of environmental protection dust removal and relates to a dry dust removal system for hydrogen-based vertical furnace discharge. Background Art

[0002] The steel industry is a major carbon emitter in my country. In order to reduce carbon emissions, it is accelerating the adoption of new low-carbon smelting processes to replace traditional blast furnace smelting processes. Hydrogen-based vertical furnaces are one of the important development directions. In recent years, there have been many demonstration projects in China. However, hydrogen-based vertical furnaces only solve the carbon emission problem in the smelting process, and the dust pollution of its product direct reduced iron still exists. Due to the flammable and explosive characteristics of direct reduced iron, wet dust removal is currently used for hydrogen-based vertical furnace discharge dust removal at home and abroad. However, wet dust removal consumes a lot of water, and there are reasons such as wastewater pollution and low dust removal efficiency, making it difficult to achieve true low-carbon environmental protection. The national ultra-low emission implementation opinions of the steel industry also put forward higher requirements for wastewater and exhaust gas pollution in the steel industry.

[0003] In the context of ultra-low emissions in the steel industry, there is an urgent need to propose a dry dust removal system suitable for hydrogen-based vertical furnace discharge and solve the flammable and explosive problems of direct reduced iron in dry dust removal to achieve dry dust removal for hydrogen-based vertical furnace discharge. Utility Model Content

[0004] In view of this, the purpose of the utility model is to provide a dry dust removal system for hydrogen-based vertical furnace discharge, focusing on solving the flammable and explosive problems of direct reduced iron in dry dust removal, so as to realize dry dust removal of hydrogen-based vertical furnace discharge. The dry dust removal system has no wastewater pollution, high dust removal efficiency, and can meet the national ultra-low emission standards.

[0005] In order to achieve the above object, the utility model provides the following technical solutions:

[0006] A dry dust removal system for hydrogen-based vertical furnace discharge, comprising a dust removal hood, a spark arrester, a spark extinguisher and a bag dust collector connected in sequence through a flue gas duct along the flow direction of the hydrogen-based vertical furnace discharge, wherein the dust removal hood is connected to the discharge port of the hydrogen-based vertical furnace;

[0007] A primary spark detection system is provided between the spark arrester and the spark extinguisher, and the spark extinguisher is connected to a nitrogen system so that nitrogen is sprayed into the spark extinguisher through the nitrogen system when the primary spark detection system detects a spark.

[0008] Furthermore, a secondary spark detection system is provided in front of the entrance of each chamber in the bag-type dust collector, an automatic quick shut-off valve is provided at the entrance and outlet of each chamber in the bag-type dust collector, and a temperature detection device and a nitrogen filling device are provided in each chamber, so that when the temperature detection device of a chamber detects that the temperature exceeds the standard or the secondary spark detection system detects a spark, nitrogen is sprayed into the corresponding chamber through the nitrogen filling device.

[0009] Furthermore, an air-locking ash-discharging valve and an intermediate ash hopper connected to the air-locking ash-discharging valve are provided at the bottom of each chamber and spark arrester in the bag-type dust collector, and a temperature detection device and a nitrogen filling device are provided on the intermediate ash hopper, so that when the temperature detection device of a certain intermediate ash hopper detects that the temperature exceeds the standard, nitrogen is sprayed into the corresponding intermediate ash hopper through the nitrogen filling device.

[0010] Furthermore, the nitrogen filling devices are all connected to a nitrogen system.

[0011] Furthermore, the spark extinguisher is a nitrogen nozzle arranged in a ring shape along the flue gas duct.

[0012] Furthermore, it also includes a fan and an exhaust pipe which are connected in sequence after the bag filter through a flue gas duct.

[0013] The beneficial effects of the utility model are:

[0014] The utility model provides a dry dust removal system for hydrogen-based vertical furnace discharge, which solves the flammable and explosive problems of direct reduced iron flue gas in dry dust removal, realizes dry dust removal of hydrogen-based vertical furnace discharge, has the advantages of no water consumption, no wastewater pollution, high dust removal efficiency, and good treatment effect, and realizes the ultra-low emission requirements of the national steel industry.

[0015] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and will be apparent to those skilled in the art based on the following examination and research, or can be taught from the practice of the present invention to some extent. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be described in detail below in conjunction with the accompanying drawings, in which:

[0017] Figure 1 The utility model is a schematic structural diagram of a dry dust removal system for hydrogen-based vertical furnace discharge.

[0018] Figure numerals: 1-dust hood at the discharge port of the vertical furnace, 2-spark catcher, 3-spark extinguisher, 4-bag dust collector, 5-fan, 6-exhaust pipe, 7-primary spark detection system, 8-secondary spark detection system, 9-automatic quick shut-off valve, 10-air lock ash unloading valve, 11, intermediate ash hopper, 12-temperature detection, 13-nitrogen filling device, 14-nitrogen system. DETAILED DESCRIPTION

[0019] The following describes the implementation of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. The following embodiments and the features in the embodiments can be combined with each other without conflict.

[0020] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present utility model. In order to better illustrate the embodiments of the present utility model, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0021] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate directions or positional relationships, they are based on the directions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0022] See also Figure 1 , which is a dry dust removal system for hydrogen-based vertical furnace discharge, comprising a dust hood 1, a spark arrester 2, a spark extinguisher 3, a bag filter 4, a fan 5 and an exhaust pipe 6 which are sequentially connected through a flue gas duct along the flow direction of hydrogen-based vertical furnace discharge (direct reduced iron dust flue gas), and the dust hood 1 is connected to the discharge port of the hydrogen-based vertical furnace;

[0023] A primary spark detection system 7 is provided between the spark arrester 2 and the spark extinguisher 3 , and a secondary spark detection system 8 is provided before the entrance of each chamber in the bag filter 4 .

[0024] Preferably, an automatic quick shut-off valve 9 is provided between the secondary spark detection system 8 and the inlet of each chamber in the bag-type dust collector 4 and at the outlet of each chamber in the bag-type dust collector 4 .

[0025] Furthermore, an air-locking ash-discharging valve 10 and an intermediate ash hopper 11 connected to the air-locking ash-discharging valve 10 are provided at the bottom of each chamber in the bag filter 4 and the spark arrester 2, and a temperature detection device 12 and a nitrogen charging device 13 are provided on the intermediate ash hopper 11.

[0026] Preferably, a temperature detection device 12 and a nitrogen filling device 13 are provided in each chamber of the bag filter 4 .

[0027] Each of the nitrogen charging devices 13 is connected to a nitrogen system 14, and the nitrogen system 14 is also connected to the spark arrester 3 through a nitrogen pipeline, so as to provide nitrogen to the spark arrester 2, the spark arrester 3, the bag filter 4 and the intermediate ash hopper 11 through the nitrogen system 14; it mainly includes a nitrogen storage tank and a pipeline network.

[0028] In this embodiment, the bag filter 4 has a plurality of chambers, preferably four chambers.

[0029] Preferably, the spark extinguisher is a nitrogen nozzle arranged in a ring shape along the flue gas duct.

[0030] During operation, the direct reduced iron dust flue gas discharged from the discharge port of the hydrogen-based vertical furnace is captured by the dust hood 1, and then first enters the spark arrester 2 to remove sparks. Then the primary spark detection system 7 detects the flue gas. If sparks can still be detected, the interlocking spark extinguisher 3 will be activated. The spark extinguisher is a nitrogen nozzle arranged in a ring along the pipeline. A large amount of nitrogen is instantly sprayed into the nitrogen curtain to extinguish the sparks when they pass through. After passing through the spark extinguisher 3, the flue gas enters the bag filter 4. The entrance of each chamber of each bag filter 4 is equipped with a secondary spark detection system 8. If the secondary spark detection system 8 of a chamber detects a spark, the automatic quick shut-off valve 9 of the entrance and exit of the chamber is immediately interlocked and closed, and the nitrogen filling device 13 is opened for nitrogen filling protection, thereby solving the flammable and explosive problem of direct reduced iron. After dust removal by the bag filter 4, the flue gas enters the fan 5, and then is discharged into the atmosphere through the exhaust pipe 6.

[0031] The lower part of each chamber of the spark arrester 2 and the bag dust collector 4 is provided with an air lock ash discharge valve 10, and the lower part of the air lock ash discharge valve 10 is provided with an intermediate ash hopper 11. The air lock ash discharge valve 10 works continuously to ensure that there is no ash in each chamber of the spark arrester 2 and the bag dust collector 4. The intermediate ash hopper 11 is provided with a nitrogen filling device 13 and a temperature detection device 12 to control the dust in the intermediate ash hopper 11 from spontaneous combustion.

[0032] Specifically, the primary spark detection system 7, the secondary spark detection system 8, the automatic quick shut-off valve 9, the temperature detection device 12, the nitrogen charging device 13 and the nitrogen system 14 in this embodiment are all connected to an external control system (not shown), thereby realizing the linkage control of the dry dust removal system. The external control system can realize the linkage control function by using a conventional PLC control system or a computer control system in the prior art, so it will not be described in detail.

[0033] In another embodiment, the primary spark detection system 7, the spark extinguisher 3 and the nitrogen system can be separately set as a linkage control mechanism; the secondary spark detection system 8, the automatic quick shut-off valve 9, the nitrogen charging device 13 in the bag filter 4, the temperature detection device 12 and the nitrogen system can be set as a linkage control mechanism; the temperature detection device 12 and the nitrogen charging device 13 in the intermediate ash hopper and the nitrogen system can be set as a linkage control mechanism, so there is no need to introduce an external control system.

[0034] In another embodiment, the operator may observe the corresponding temperature detection device and spark detection system and then perform corresponding linkage control operations.

[0035] The control method for the combustion and explosion prevention of the hydrogen-based vertical furnace discharge dry dust removal system is:

[0036] 1) When the primary spark detection system 7 detects a spark, the spark extinguisher 3 is activated and nitrogen is sprayed in to extinguish the fire;

[0037] 2) When the secondary spark detection system 8 detects a spark, the automatic quick shut-off valve 9 at the inlet and outlet of the corresponding chamber in the bag filter 4 is cut off, and the chamber is filled with nitrogen for protection through the nitrogen filling device 13;

[0038] 3) When the temperature detection device 12 of a certain chamber of the bag filter 4 detects that the temperature exceeds the standard, the automatic quick shut-off valve 9 at the entrance and exit of the corresponding chamber is closed, and the nitrogen filling device 13 is activated to perform nitrogen filling protection;

[0039] 4) When the temperature detection device 12 of the intermediate ash hopper of the spark arrester or bag filter 4 detects that the temperature exceeds the standard, the nitrogen filling device 13 of the intermediate ash hopper 11 is activated to perform nitrogen filling protection.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the utility model.

Claims

1. A dry dust removal system for hydrogen-based vertical furnace discharge, characterized in that: It includes a dust hood, a spark arrester, a spark extinguisher and a bag dust collector which are sequentially connected through a flue gas duct along the flow direction of the discharge of the hydrogen-based vertical furnace, and the dust hood is connected to the discharge port of the hydrogen-based vertical furnace; A primary spark detection system is provided between the spark arrester and the spark extinguisher, and the spark extinguisher is connected to a nitrogen system so that nitrogen is sprayed into the spark extinguisher through the nitrogen system when the primary spark detection system detects a spark.

2. The dry dust removal system for hydrogen-based vertical furnace discharge according to claim 1 is characterized in that: A secondary spark detection system is provided in front of the entrance of each chamber in the bag-type dust collector, an automatic quick shut-off valve is provided at the entrance and outlet of each chamber in the bag-type dust collector, and a temperature detection device and a nitrogen filling device are provided in each chamber, so that nitrogen can be sprayed into the corresponding chamber through the nitrogen filling device when the temperature detection device of a chamber detects that the temperature exceeds the standard or the secondary spark detection system detects a spark.

3. The dry dust removal system for hydrogen-based vertical furnace discharge according to claim 2 is characterized in that: An air-locking ash-discharging valve and an intermediate ash hopper connected to the air-locking ash-discharging valve are provided at the bottom of each chamber and the spark arrester in the bag filter, and a temperature detection device and a nitrogen filling device are provided on the intermediate ash hopper, so that nitrogen can be sprayed into the corresponding intermediate ash hopper through the nitrogen filling device when the temperature detection device of a certain intermediate ash hopper detects that the temperature exceeds the standard.

4. The dry dust removal system for hydrogen-based vertical furnace discharge according to claim 3 is characterized in that: The nitrogen filling devices are all connected to the nitrogen system.

5. The dry dust removal system for hydrogen-based vertical furnace discharge according to claim 1 is characterized in that: The spark extinguisher is a nitrogen nozzle arranged in a ring shape along the flue gas duct.

6. The dry dust removal system for hydrogen-based vertical furnace discharge according to claim 1, characterized in that: It also includes a fan and an exhaust pipe which are connected in sequence after the bag filter through a flue gas duct.

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