Environment-friendly treatment system for flue gas of blast furnace hot blast stove

Abstract

The utility model provides an environment-friendly treatment system for flue gas of a blast furnace hot blast stove. The environment-friendly treatment system comprises a desulfurization assembly, a dust removal assembly, an induced draft fan, a smoke exhaust piece, an ash conveying assembly, an ash collecting assembly and a back flushing pipeline, the desulfurization assembly is communicated with the input end of hot-blast stove flue gas, the desulfurization assembly is used for desulfurizing the hot-blast stove flue gas, the desulfurization assembly, the dust removal assembly, the induced draft fan and the smoke exhaust part are sequentially connected in series through a pipeline, a dust removal pneumatic butterfly valve is arranged between the desulfurization assembly and the dust removal assembly, and a reverse blowing switching valve is arranged between the dust removal assembly and the induced draft fan; the ash conveying assembly is communicated with a nitrogen gas source, the ash conveying assembly is communicated with a dust outlet of the dust removal assembly, and the ash collecting assembly is communicated with the ash conveying assembly; the reverse blowing pipeline is communicated with the induced draft fan and the reverse blowing switching valve, and a reverse blowing pneumatic butterfly valve is arranged on the reverse blowing pipeline. According to the utility model, a nitrogen pulse back flushing technology is not used for back flushing, so that the filtering cost can be greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental protection systems, in particular to an environmental protection treatment system for blast furnace hot blast stove flue gas. Background Art

[0002] In industrial production, in order to ensure that the SO2 emissions from the blast furnace hot blast stove flue gas meet the ultra-low emission requirements, it is necessary to build a desulfurization device to purify the hot blast stove flue gas. The use of SDS desulfurization is the mainstream blast furnace hot blast stove flue gas desulfurization process in China.

[0003] The SDS desulfurization process is to inject calcium-based or sodium-based desulfurizer to absorb sulfur in the hot blast furnace flue gas, and then filter the desulfurized flue gas before discharging it. The industry generally uses nitrogen pulse back-blowing powder collectors to filter dust particles in the hot blast furnace flue gas after desulfurization. However, the use of nitrogen pulse back-blowing technology consumes a large amount of nitrogen as an external power medium, resulting in an increase in filtration costs. In addition, the nitrogen pulse back-blowing technology also has the following disadvantages:

[0004] a) The nitrogen pulse system has many valves and a high failure rate, especially the pulse valves of key equipment are easily damaged, and a pulse valve failure will affect the operation of a powder collector box;

[0005] b) Limited by the pulse valve's spraying capacity, the length of the bag is generally no more than 8.0m, so the bag's filtering area cannot be increased in the length direction, which limits the filtering effect;

[0006] c) The nitrogen pulse back-blowing powder collector is fixed with a bag cage + lattice plate. A bag replacement space of about 2-3m in height needs to be reserved above the lattice plate of the box, resulting in a waste of filtering space;

[0007] Therefore, it is necessary to provide a blast furnace hot blast stove flue gas environmental protection treatment system that solves the above problems. Summary of the invention

[0008] The utility model aims to solve one of the above-mentioned technical problems and provides a blast furnace hot blast stove flue gas environmental protection treatment system, which does not use nitrogen pulse backblowing technology for backblowing and can greatly reduce the filtration cost.

[0009] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is:

[0010] A blast furnace hot blast stove flue gas environmental protection treatment system, comprising a desulfurization component, a dust removal component, an induced draft fan, a smoke exhaust component, an ash conveying component, an ash collecting component and a back-blowing pipeline; the desulfurization component is connected with the input end of the hot blast stove flue gas, the desulfurization component is used to desulfurize the hot blast stove flue gas, the desulfurization component, the dust removal component, the induced draft fan and the smoke exhaust component are sequentially connected in series through pipelines, a dust removal pneumatic butterfly valve is arranged between the desulfurization component and the dust removal component, and a back-blowing switching valve is arranged between the dust removal component and the induced draft fan; the ash conveying component is connected with a nitrogen gas source, the ash conveying component is connected with the dust outlet of the dust removal component, and the ash collecting component is connected with the ash conveying component; the back-blowing pipeline is connected with the induced draft fan and the back-blowing switching valve, and a back-blowing pneumatic butterfly valve is arranged on the back-blowing pipeline.

[0011] Furthermore, the dust removal component includes a powder collector, which is connected to the desulfurization component through a dust removal pipeline. The dust removal pneumatic butterfly valve is arranged on the dust removal pipeline. The outlet of the powder collector facing away from the dust removal pipeline is provided with an exhaust pipeline, and the back-blow switching valve is arranged on the exhaust pipeline; the induced draft fan is connected to the exhaust pipeline.

[0012] Furthermore, the powder collector includes a clean air zone and a dusty air zone, the clean air zone is connected to the dusty air zone and the clean air zone is located above the dusty air zone, a grating plate is provided at the connection between the clean air zone and the dusty air zone, a dust removal bag is connected to the side of the grating plate facing the clean air zone, and the dust removal bag extends along the height direction of the clean air zone; the dust removal pipeline is connected to the dusty air zone; the ash conveying assembly is connected to the dust outlet of the dusty air zone.

[0013] Furthermore, an electric gate valve and a first ash discharge valve are provided between the ash conveying assembly and the dust outlet of the dust and gas zone, and the electric gate valve is located between the first ash discharge valve and the dust and gas zone.

[0014] Furthermore, the ash conveying component includes a pneumatic ash unloading pipeline, a first pneumatic ash conveying valve and a second pneumatic ash conveying valve, the pneumatic ash unloading pipeline connects the nitrogen gas source and the ash collecting component, and the pneumatic ash unloading pipeline is connected to the first ash unloading valve; the first pneumatic ash conveying valve is arranged at the nitrogen gas source inlet of the pneumatic ash unloading pipeline, and the second pneumatic ash conveying valve is arranged between the first ash unloading valve and the ash collecting component.

[0015] Furthermore, there are a plurality of powder collectors, and the plurality of powder collectors are arranged in parallel.

[0016] Furthermore, the length of the dust removal bag is 8-12m.

[0017] Furthermore, the desulfurization component includes a reactant storage tank and a reactor, the reactor is connected to the input end of the hot blast furnace flue gas, and the reactant storage tank is connected to the reactor; the dust removal component is connected in series with the reactor.

[0018] Furthermore, the ash collecting component includes an ash bin and a second ash unloading valve, the ash bin is communicated with the ash conveying component, and the second ash unloading valve is installed at the discharge port of the ash bin.

[0019] Due to the adoption of the above technical solution, the utility model has the following beneficial effects:

[0020] When using the above-mentioned blast furnace hot blast furnace flue gas environmental protection treatment system, the dust removal pneumatic butterfly valve, the back-blowing pneumatic butterfly valve, the induced draft fan and the forward blowing function of the back-blowing switching valve are turned on, and the hot blast furnace flue gas is desulfurized by the desulfurization component to obtain a desulfurized gas-ash mixture, and the gas-ash mixture is dedusted by the dust removal component. At this time, some dust particles in the desulfurized flue gas are retained in the dust removal component, and some dust particles will enter the ash conveying component and be transported to the ash collecting component for collection through the ash conveying component, then the dust removal flue gas is discharged from the air outlet of the dust removal component, and the dust removal pneumatic butterfly valve is closed. The dust removal flue gas is discharged from the air outlet of the dust removal component. Under the action of , the dust removal flue gas enters the back-blowing pipeline, and the back-blowing function of the back-blowing switching valve is turned on. The dust removal flue gas enters the dust removal component again from the back-blowing switching valve under the guidance of the back-blowing pipeline, and back-blowing the dust particles retained in the dust removal component. At this time, the dust particles originally retained in the dust removal component are blown off and enter the ash conveying component. The back-blowing function of the back-blowing switching valve and the back-blowing pneumatic butterfly valve are closed, and the dust removal flue gas is finally discharged from the exhaust part of the system through the induced draft fan, thus ending a cycle of hot blast furnace flue gas treatment. When continuous hot blast furnace flue gas treatment is performed, the above cycle can be repeated. It can be seen from the above process that the utility model does not use nitrogen pulse back-blowing technology for back-blowing, which can greatly reduce the filtration cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural schematic diagram of the blast furnace hot blast stove flue gas environmental protection treatment system.

[0022] 1- reactant storage tank, 2- reactor, 3- dust removal pipeline, 4- grid plate, 5- powder collector, 51- clean air zone, 52- dust gas zone, 6- dust removal bag, 7- backblowing switching valve, 8- backblowing pipeline, 9- exhaust pipeline, 10- induced draft fan, 11- flue gas pipe three, 12- backblowing pneumatic butterfly valve, 13- first pneumatic butterfly valve, 14- chimney, 15- electric gate valve, 16- first ash unloading valve, 17- first pneumatic ash conveying valve, 18- second pneumatic ash conveying valve, 19- pneumatic ash unloading pipeline, 20- ash bin, 21- second ash unloading valve, 22- air inlet valve, 23- direct transmission pipeline, 24- spare valve. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0026] like Figure 1 As shown, a preferred embodiment of the utility model provides an environmental protection treatment system for blast furnace hot blast furnace flue gas, including a desulfurization component, a dust removal component, an induced draft fan 10, a smoke exhaust component 14, an ash conveying component, an ash collecting component and a back-blowing pipeline 8. The desulfurization component is connected to the input end of the hot blast furnace flue gas, and the desulfurization component is used to desulfurize the hot blast furnace flue gas. The desulfurization component, the dust removal component, the induced draft fan 10 and the smoke exhaust component 14 are connected in series in sequence through pipelines. A dust removal pneumatic butterfly valve 13 is provided between the desulfurization component and the dust removal component, and a back-blowing switching valve 7 is provided between the air outlet of the dust removal component and the induced draft fan 10. The smoke exhaust component 14 is a chimney. The ash conveying component is connected to the nitrogen gas source, the ash conveying component is connected to the dust outlet of the dust removal component, and the ash collecting component is connected to the ash conveying component; the back-blowing pipeline 8 is connected to the induced draft fan 10 and the back-blowing switching valve 7, and a back-blowing pneumatic butterfly valve 12 is provided on the back-blowing pipeline 8.

[0027] When using the above-mentioned blast furnace hot blast furnace flue gas environmental protection treatment system, the dust removal pneumatic butterfly valve 13, the back-blowing pneumatic butterfly valve 12, the induced draft fan 10 and the forward blowing function of the back-blowing switching valve 7 are turned on, and the hot blast furnace flue gas is desulfurized by the desulfurization component to obtain a desulfurized gas-ash mixture, and the gas-ash mixture is dedusted by the dust removal component. At this time, some dust particles in the desulfurized flue gas are retained in the dust removal component, and some dust particles will enter the ash conveying component and be transported to the ash collecting component for collection through the ash conveying component, then the dust removal flue gas is discharged from the air outlet of the dust removal component, and the dust removal pneumatic butterfly valve 13 is closed. The dust removal flue gas is discharged from the air outlet of the dust removal component. Under the action of , the dust removal gas enters the back-blowing pipeline 8, and the back-blowing function of the back-blowing switching valve 7 is turned on. The dust removal gas enters the dust removal component again from the back-blowing switching valve 7 under the guidance of the back-blowing pipeline 8, and back-blowing the dust particles retained in the dust removal component. At this time, the dust particles originally retained in the dust removal component are blown off and enter the ash conveying component. The back-blowing function of the back-blowing switching valve 7 and the back-blowing pneumatic butterfly valve 12 are closed. The dust removal gas is finally discharged from the system from the smoke exhaust part 14 through the induced draft fan 10, and a cycle of hot blast furnace flue gas treatment is ended. When continuous hot blast furnace flue gas treatment is performed, the above cycle can be repeated. It can be seen from the above process that the utility model does not use nitrogen pulse back-blowing technology for back-blowing, which can greatly reduce the filtration cost.

[0028] It is understandable that in actual industrial production, the user can choose the timing of backblowing treatment according to the actual flue gas treatment conditions. When it is necessary to backblow the dust particles retained in the dust removal component, the backblowing function of the backblowing switching valve 7 and the backblowing pneumatic butterfly valve 12 can be turned on at the same time; when backblowing operation is not required, the backblowing pneumatic butterfly valve 12 can be closed and the forward blowing function of the backblowing switching valve 7 can be turned on.

[0029] In this embodiment, the dust removal component includes a powder collector 5, which is connected to the desulfurization component through a dust removal pipeline 3. The dust removal pneumatic butterfly valve 13 is arranged on the dust removal pipeline 3. The outlet of the powder collector 5 facing away from the dust removal pipeline 3 is provided with an exhaust pipeline 9, and a back-blowing switching valve 7 is arranged on the exhaust pipeline 9; the induced draft fan 10 is connected to the exhaust pipeline 9.

[0030] In this embodiment, the number of powder collectors 5 is several, specifically three, and the three powder collectors 5 are arranged in parallel: the three powder collectors 5 are all connected to the desulfurization assembly through the dust removal pipeline 3, and a dust removal pneumatic butterfly valve 13 is provided at the entrance of each powder collector 5; the gas outlets of the three powder collectors 5 are all connected to the exhaust pipeline 9 and are respectively connected to a backflush switching valve 7, and the backflush pipeline 8 is connected to the backflush switching valves 7 connected to the several powder collectors 5. The number of powder collectors 5 is multiple, which can increase the filtering efficiency of the utility model.

[0031] In this embodiment, the powder collector 5 includes a clean air zone 51 and a dusty gas zone 52. The clean air zone 51 is connected to the dusty gas zone 52 and the clean air zone 51 is located above the dusty gas zone 52. A lattice plate 4 is provided at the connection between the clean air zone 51 and the dusty gas zone 52. A dust bag 6 is connected to the side of the lattice plate 4 facing the clean air zone 51. The dust bag 6 extends along the height direction of the clean air zone 51. The length of the dust bag 6 is 8-12m, specifically 10m. The dust removal pipeline 3 is connected to the dusty gas zone 52, that is, the dust removal pipeline 3 is connected to the side wall of the dusty gas zone 52; the ash conveying assembly is connected to the dust outlet at the bottom of the dusty gas zone 52. Since the present embodiment does not use nitrogen pulse backflush technology for backflush, the length of the dust bag 6 can be adjusted according to the volume of the powder collector 5, so as to obtain a dust bag 6 length and a powder collector 5 space that can achieve higher filtration efficiency. In addition, the manufacturer can backflush and remove dust from the dust bag 6 by controlling the corresponding backflush switching valve 7 according to the accumulation of dust particles in the dust bag 6 in the powder collector 5 .

[0032] In this embodiment, an electric gate valve 15 and a first ash unloading valve 16 are provided between the ash conveying component and the dust outlet of the dust and gas zone 52. Specifically, an electric gate valve 15 and a first ash unloading valve 16 are connected below the dust outlets of several powder collectors 5; and the electric gate valve 15 is located between the first ash unloading valve 16 and the dust and gas zone 52. Specifically: the ash conveying component includes a pneumatic ash unloading pipeline 19, a first pneumatic ash conveying valve 17 and a second pneumatic ash conveying valve 18. The pneumatic ash unloading pipeline 19 connects the nitrogen gas source and the ash collecting component, and the pneumatic ash unloading pipeline 19 is connected to several first ash unloading valves 16; the first pneumatic ash conveying valve 17 is provided at the nitrogen gas source inlet of the pneumatic ash unloading pipeline 19, the second pneumatic ash conveying valve 18 is provided between the first ash unloading valve 16 and the ash collecting component, and the second pneumatic ash conveying valve 18 is located between the first ash unloading valve 16 connected to the last powder collector 5 and the ash collecting component. When the dust particles in the powder collector 5 need to be collected, the electric gate valve 15, the first ash unloading valve 16, the first pneumatic ash conveying valve 17 and the second pneumatic ash conveying valve 18 are opened, and the dust particles are drained to the pneumatic ash unloading pipeline 19, and nitrogen is pumped in from the pneumatic ash unloading pipeline 19. The nitrogen gas source is used as a power source to transport the dust particles to the ash collecting component for collection.

[0033] In this embodiment, the desulfurization component includes a reactant storage tank 1 and a reactor 2. The reactor 2 is connected to the input end of the hot blast furnace flue gas. An air inlet valve 22 is provided between the reactor 2 and the input end of the hot blast furnace flue gas. The reactant storage tank 1 is connected to the reactor 2. The dust removal component is connected in series with the reactor 2. Specifically, the three powder collectors 5 are connected to the reactor 2 through the dust removal pipeline 3. The reactant storage tank 1 is used to store the desulfurization reactant, which is used to pump the desulfurization reactant toward the reactor 2, and then perform the desulfurization reaction in the reactor 2. The desulfurization component is a prior art and will not be described in detail here.

[0034] In this embodiment, the ash collection component includes an ash bin 20 and a second ash discharge valve 21. The ash bin 20 is connected to the ash conveying component, and specifically, the ash bin 20 is connected to the pneumatic ash discharge pipeline 19. The second ash discharge valve 21 is installed at the discharge port of the ash bin 20. The ash bin 20 is used to collect dust particles, and the second ash discharge valve 21 is used to open or close the discharge port of the ash bin 20.

[0035] In this embodiment, the input end of the hot blast furnace smoke is directly connected to the smoke exhaust part 14 by a direct transmission pipeline 23, and a spare valve 24 is provided on the direct transmission pipeline 23. When the hot blast furnace smoke is generated and meets the emission standard, the production party can open the spare valve 24 and choose to discharge the smoke from the direct transmission pipeline 23. When the smoke needs to be processed, the spare valve 24 remains closed.

[0036] It can be understood that in other embodiments, the direct transmission pipeline 23 and the backup valve 24 can be omitted.

[0037] It can be understood that the pneumatic ash unloading pipeline 19 is not limited to being connected to a nitrogen gas source as a power source in the present embodiment. In other embodiments, the pneumatic ash unloading pipeline 19 can be connected to an air gas source as a power source.

[0038] The above description is a detailed description of the preferred feasible embodiment of the utility model, but the embodiment is not used to limit the scope of the patent application of the utility model. All equivalent changes or modified changes completed under the technical spirit suggested by the utility model should fall within the patent scope covered by the utility model.

Claims

1. A blast furnace hot blast stove flue gas environmental protection treatment system, characterized in that: The invention comprises a desulfurization component, a dust removal component, an induced draft fan (10), a smoke exhaust component (14), an ash conveying component, an ash collecting component and a back-blowing pipeline (8); the desulfurization component is connected to the input end of the hot blast furnace flue gas, the desulfurization component is used to desulfurize the hot blast furnace flue gas, the desulfurization component, the dust removal component, the induced draft fan (10) and the smoke exhaust component (14) are sequentially connected in series through pipelines, a dust removal pneumatic butterfly valve (13) is arranged between the desulfurization component and the dust removal component, and a back-blowing switching valve (7) is arranged between the dust removal component and the induced draft fan (10); the ash conveying component is connected to a nitrogen gas source, the ash conveying component is connected to the dust outlet of the dust removal component, and the ash collecting component is connected to the ash conveying component; the back-blowing pipeline (8) is connected to the induced draft fan (10) and the back-blowing switching valve (7), and a back-blowing pneumatic butterfly valve (12) is arranged on the back-blowing pipeline (8).

2. A blast furnace hot blast stove flue gas environmental protection treatment system as claimed in claim 1, characterized in that: The dust removal component comprises a powder collector (5), the powder collector (5) is connected to the desulfurization component via a dust removal pipeline (3), the dust removal pneumatic butterfly valve (13) is arranged on the dust removal pipeline (3), an exhaust pipeline (9) is arranged at the outlet of the powder collector (5) away from the dust removal pipeline (3), and the back-blowing switching valve (7) is arranged on the exhaust pipeline (9); the induced draft fan (10) is connected to the exhaust pipeline (9).

3. A blast furnace hot blast stove flue gas environmental protection treatment system as claimed in claim 2, characterized in that: The powder collector (5) comprises a clean air zone (51) and a dusty air zone (52); the clean air zone (51) is connected to the dusty air zone (52) and the clean air zone (51) is located above the dusty air zone (52); a lattice plate (4) is provided at the connection between the clean air zone (51) and the dusty air zone (52); a dust removal bag (6) is connected to the side of the lattice plate (4) facing the clean air zone (51); the dust removal bag (6) extends in the height direction of the clean air zone (51); the dust removal pipeline (3) is connected to the dusty air zone (52); and the ash conveying assembly is connected to a dust outlet of the dusty air zone (52).

4. A blast furnace hot blast stove flue gas environmental protection treatment system as claimed in claim 3, characterized in that: An electric gate valve (15) and a first ash discharge valve (16) are provided between the ash conveying component and the dust outlet of the dust and gas zone (52), and the electric gate valve (15) is located between the first ash discharge valve (16) and the dust and gas zone (52).

5. A blast furnace hot blast stove flue gas environmental protection treatment system as claimed in claim 4, characterized in that: The ash conveying component comprises a pneumatic ash unloading pipeline (19), a first pneumatic ash conveying valve (17) and a second pneumatic ash conveying valve (18); the pneumatic ash unloading pipeline (19) is connected to a nitrogen gas source and the ash collecting component, and the pneumatic ash unloading pipeline (19) is connected to the first ash unloading valve (16); the first pneumatic ash conveying valve (17) is arranged at the nitrogen gas source inlet of the pneumatic ash unloading pipeline (19), and the second pneumatic ash conveying valve (18) is arranged between the first ash unloading valve (16) and the ash collecting component.

6. A blast furnace hot blast stove flue gas environmental protection treatment system as claimed in claim 2, characterized in that: The number of the powder collectors (5) is several, and the several powder collectors (5) are arranged in parallel.

7. A blast furnace hot blast stove flue gas environmental protection treatment system as claimed in claim 3, characterized in that: The length of the dust removal bag (6) is 8-12m.

8. The blast furnace hot blast stove flue gas environmental protection treatment system according to claim 1, characterized in that: The desulfurization component comprises a reactant storage tank (1) and a reactor (2), wherein the reactor (2) is connected to the input end of the hot blast furnace flue gas, and the reactant storage tank (1) is connected to the reactor (2); the dust removal component is connected in series with the reactor (2).

9. The blast furnace hot blast stove flue gas environmental protection treatment system according to claim 1, characterized in that: The ash collecting component comprises an ash bin (20) and a second ash discharging valve (21); the ash bin (20) is connected to the ash conveying component; and the second ash discharging valve (21) is installed at the discharge port of the ash bin (20).

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