Damping large-emission recovery dust removal system

Abstract

The invention provides a damping-down large-diffusion recovery dust removal system which comprises a diffusion pipe, the diffusion pipe is arranged at the top of a blast furnace, the diffusion pipe is communicated with a nitrogen tank and a dust remover through a nitrogen replacement loop and a damping-down gas loop respectively, and the nitrogen tank is further communicated with the dust remover through a nitrogen ash removal loop; damping-down coal gas is connected into a dust remover through double bleeding pipes at the furnace top, bleeding is conducted through the dust remover after damping-down is completed, damping-down recycling operation is added on the basis of damping-down safe operation, air pressure of an air opening is controlled and reduced, top pressure is reduced, residual coal gas at the furnace top is recycled through a damping-down ejection system, and after the bleeding condition is met, the newly-added dust remover is started to purify residual smoke dust. Starting furnace top large diffusion to complete a damping down process; the system is matched with a damping-down, diffusing and recycling system, part of gas which cannot be recycled is purified and discharged, air pollution is reduced, safe use is guaranteed, compared with the prior art, the system is more mature, and visual pollution and environmental pollution caused by secondary emission are avoided.

Description

Technical Field

[0001] The invention relates to the field of recovery of large-dispersed coal gas at the top of a blast furnace, and in particular to a large-dispersed recovery and dust removal system for a resting wind. Background Art

[0002] During the blast furnace smelting production process, the blast furnace shut-off gas from the furnace top is usually discharged directly into the atmosphere. The shut-off gas is a toxic, flammable, mixed gas containing a large amount of CO, CO2 and dust, which is extremely easy to cause atmospheric pollution and also wastes energy.

[0003] Considering that a large amount of dusty coal gas is generated when blast furnaces are shut down for maintenance, direct discharge into the air will seriously affect the environment. Therefore, there is currently a technology for recovering the wind, but the technology may have problems such as incomplete recovery at the end of the recovery period or being unsuitable for recovering part of the coal gas, so it still needs to be discharged into the air.

[0004] Based on the above problems, there is an urgent need for a large-scale recovery and dust removal system for wind-down venting that can solve the problem of coal gas emission from wind-down venting. Summary of the invention

[0005] The purpose of the present invention is to provide a large-scale dust recovery and removal system for idle air to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a large-scale venting and dust-removing system for resting air, comprising a venting pipe, wherein the venting pipe is arranged on the top of a blast furnace, and the venting pipe is connected to a nitrogen tank and a dust collector through a nitrogen replacement circuit and a resting air gas circuit respectively, and the nitrogen tank is also connected to the dust collector through a nitrogen cleaning circuit.

[0008] Preferably, at least two groups of emission pipes are provided.

[0009] Preferably, the nitrogen replacement circuit comprises a nitrogen replacement pipeline, one end of which is connected to the outlet of the nitrogen tank and the other end of which is connected to the top of the vent pipe, and a pneumatic regulating valve is provided on the nitrogen replacement pipeline.

[0010] Preferably, the off-gas gas circuit includes an off-gas gas pipeline, one end of which is connected to the middle of the vent pipe, and the other end is connected to the inlet of the dust collector. A pneumatic regulating valve and an electric blind plate valve are provided on the off-gas gas pipeline.

[0011] Preferably, the nitrogen cleaning circuit comprises a nitrogen cleaning pipe, one end of which is connected to the outlet of the nitrogen tank and the other end of which is connected to the inlet of the dust collector, and a pneumatic regulating valve is provided on the nitrogen cleaning pipe.

[0012] Compared with the prior art, the present invention has achieved the following beneficial technical effects:

[0013] The invention provides a large-scale venting and dust-removing system for wind-down, comprising a venting pipe, wherein the venting pipe is arranged on the top of a blast furnace, and the venting pipe is connected to a nitrogen tank and a dust collector through a nitrogen replacement circuit and a wind-down coal gas circuit, respectively, and the nitrogen tank is also connected to the dust collector through a nitrogen cleaning circuit; the wind-down coal gas is connected to the dust collector through a double venting pipe on the top of the furnace, and is vented through the dust collector after the wind-down is completed, and a wind-down recovery operation is added on the basis of a wind-down safety operation, and the air pressure at the tuyere is controlled to be reduced, the top pressure is reduced, and the wind-down induced draft system recovers the residual coal gas on the furnace top, and after the venting conditions are met, the newly added dust collector is started to purify the residual smoke, and the large-scale venting on the furnace top is started to complete the wind-down process; the system is matched with a wind-down venting and recovery system, and part of the coal gas that cannot be recovered is purified and discharged, thereby reducing air pollution and ensuring safe use. Compared with the existing technology, it is more mature and avoids visible pollution and environmental pollution caused by secondary emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 A schematic diagram of a large-scale dust recovery and removal system for idle air provided by the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] The purpose of the present invention is to provide a large-scale dust recovery and removal system for idle air to solve the problems existing in the prior art.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Embodiment 1:

[0020] This embodiment provides a large-scale dust recovery and removal system for idle air, such as Figure 1As shown, it includes a vent pipe 1, which is arranged on the top of the blast furnace. The vent pipe 1 is connected to a nitrogen tank 4 and a dust collector 5 through a nitrogen replacement circuit 2 and a rest gas circuit 3 respectively. The nitrogen tank 4 is also connected to the dust collector 5 through a nitrogen cleaning circuit 6.

[0021] As an implementation mode, at least two groups of vent pipes are provided.

[0022] As an embodiment, the nitrogen replacement circuit 2 includes a nitrogen replacement pipeline, one end of which is connected to the outlet of the nitrogen tank 4, and the other end of which is connected to the top of the vent pipe 1, and a pneumatic regulating valve is provided on the nitrogen replacement pipeline.

[0023] As an implementation mode, the off-gas gas circuit 3 includes an off-gas gas pipeline, one end of which is connected to the middle of the vent pipe 1, and the other end is connected to the inlet of the dust collector 5. A pneumatic regulating valve and an electric blind plate valve are provided on the off-gas gas pipeline.

[0024] As an embodiment, the nitrogen cleaning circuit 6 includes a nitrogen cleaning pipeline, one end of which is connected to the outlet of the nitrogen tank 4, and the other end of which is connected to the inlet of the dust collector 5. A pneumatic regulating valve is provided on the nitrogen cleaning pipeline.

[0025] The present invention provides a large-dispersion and recovery dust removal system for wind-down, in which wind-down coal gas is connected to a dust collector through a double dispersing pipe on the furnace top, and is discharged through the dust collector after the wind-down is completed. On the basis of wind-down safety operation, a wind-down recovery operation is added to control and reduce the air pressure at the tuyere, reduce the top pressure, and the wind-down induced gas system recovers the residual coal gas on the furnace top. After the dispersing conditions are met, the newly added dust collector is started to purify the residual smoke, and the large-scale dispersing on the furnace top is started to complete the wind-down process. The above system has been approved by Hubei Jinshenglan Iron and Steel Plant and is planned to be implemented. After expert demonstration and review, the system is safe and reliable, can meet environmental protection requirements, reduce emission pollution to the atmosphere, and can work in conjunction with clean coal gas recovery to avoid the emission of black smoke.

[0026] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A large-scale dust recovery and removal system for idle air, characterized by: It includes a vent pipe, which is arranged on the top of the blast furnace. The vent pipe is connected to a nitrogen tank and a dust collector through a nitrogen replacement circuit and a wind-down gas circuit respectively. The nitrogen tank is also connected to the dust collector through a nitrogen cleaning circuit.

2. The large-scale dust recovery and removal system for idle air according to claim 1 is characterized in that: The emission pipes are provided with at least two groups.

3. The large-scale dust recovery and removal system for idle air according to claim 1 is characterized in that: The nitrogen replacement circuit comprises a nitrogen replacement pipeline, one end of which is connected to the outlet of the nitrogen tank, and the other end of which is connected to the top of the vent pipe. A pneumatic regulating valve is provided on the nitrogen replacement pipeline.

4. The large-scale dust recovery and removal system for idle air according to claim 1 is characterized in that: The off-gas gas circuit includes an off-gas gas pipeline, one end of which is connected to the middle of the vent pipe, and the other end is connected to the inlet of the dust collector. A pneumatic regulating valve and an electric blind plate valve are provided on the off-gas gas pipeline.

5. The large-scale dust recovery and removal system for idle air according to claim 1 is characterized in that: The nitrogen cleaning circuit includes a nitrogen cleaning pipeline, one end of which is connected to the outlet of the nitrogen tank, and the other end of which is connected to the inlet of the dust collector. A pneumatic regulating valve is provided on the nitrogen cleaning pipeline.

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