Third-generation converter one-time dry dedusting system

Abstract

The utility model discloses a third-generation converter one-time dry dust removal system which comprises a high-efficiency heat exchanger, a banana bend dust remover, a rotational flow heat recovery device and a high-temperature-resistant explosion-proof ultra-clean dust remover, raw gas of a converter enters the high-efficiency heat exchanger for heat exchange and recovery, the banana bend dust remover is arranged between the high-efficiency heat exchanger and the rotational flow heat recovery device, and the high-temperature-resistant explosion-proof ultra-clean dust remover is arranged between the high-efficiency heat exchanger and the rotational flow heat recovery device. The cyclone heat recovery device is connected with at least one high-temperature-resistant explosion-proof ultra-clean dust remover, clean coal gas is formed at a gas outlet of the high-temperature-resistant explosion-proof ultra-clean dust remover, the clean coal gas is sent to a coal gas switching station after passing through a coal gas axial flow fan and a coal gas washing dehydrator, and the coal gas which is detected to be qualified is sent to a coal gas cabinet. According to the utility model, the traditional evaporation cold spray water and electrostatic dust collector process is canceled, and the high-efficiency heat exchanger and explosion-proof ultra-clean dust collector process is adopted, so that the converter gas waste heat recovery efficiency is high, and the dust removal system is safe and environment-friendly.

Description

Technical Field

[0001] This utility model discloses a third-generation converter primary dry dust removal system, belonging to the technical field of environmental dust removal equipment. Background Technology

[0002] Most converters in China's steel industry use dry dust removal systems. Currently, the most common dry dust removal systems are the first-generation converter primary dry dust removal system (LT method and DDS method) and the improved second-generation converter primary dry dust removal system (with the following configuration after the electrostatic precipitator: coal cooling pre-cooling, dual coal cooling, coal cooling + metal filter cartridge, wet electrostatic precipitator, etc.).

[0003] The existing dry dust removal systems for converter gas have the following main problems: First, the temperature is reduced directly from 900℃ to around 250℃ by spraying water mist through an evaporative cooler, resulting in a waste of this high-quality heat that is not recovered. Second, the use of electrostatic precipitators is problematic because the continuous discharge of the high-voltage power supply can easily cause an explosion if the mixed gas components inside the precipitator reach their explosive limits, damaging the equipment within the system and affecting the dust removal efficiency. In addition, the varying degrees of discharge from the high-voltage power supply can cause significant fluctuations in voltage and current between the electrodes and plates, affecting the dust removal efficiency of the electrostatic precipitator and leading to substantial fluctuations in the dust emission concentration at the chimney outlet.

[0004] Chinese document CN111575435A discloses a primary dry dust removal system for converter gas recovery of ultra-clean coal gas. The system includes a converter, an evaporative cooler, and a dust collector. The dust removal system also includes a high-temperature phase change accumulator for stabilizing flue gas temperature. The gas outlet of the converter is connected to the gas inlet of the high-temperature phase change accumulator through a vaporization cooling flue. The gas outlet of the high-temperature phase change accumulator is connected to the gas inlet of the evaporative cooler. The gas outlet of the evaporative cooler is connected to the gas inlet of the dust collector. The dust collector uses a pulse-jet high-temperature resistant ceramic fiber filter tube dust collector to replace the original electrostatic precipitator in the dust removal system. However, the use of an evaporative cooler in this design results in heat loss. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides a third-generation converter primary dry dust removal system.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0007] A third-generation converter primary dry dust removal system includes a high-efficiency heat exchanger, a banana-bend dust collector, a cyclone heat recovery device, a water-cooled chain conveyor, a raw coal gas pipe, a high-temperature resistant explosion-proof ultra-clean dust collector, a fine ash bin, a clean coal gas pipe, a coal gas axial flow fan, and a coal gas scrubbing and dehydrating device.

[0008] The inlet of the high-efficiency heat exchanger is connected with the converter through the vaporization cooling flue, the raw gas of the converter is introduced into the high-efficiency heat exchanger to exchange heat and recover, a banana bend dust collector is arranged between the high-efficiency heat exchanger and the cyclone heat recovery device, a water-cooled chain conveyor is arranged at the bottom of the banana bend dust collector, and the water-cooled chain conveyor is used to collect and output coarse ash;

[0009] The cyclone heat recovery device is connected with at least one high-temperature-resistant explosion-proof super-clean dust collector through a raw gas pipe, and the gas outlet of the high-temperature-resistant explosion-proof super-clean dust collector forms clean gas;

[0010] The gas outlet of the high-temperature-resistant explosion-proof super-clean dust collector is connected with a clean gas pipe, the clean gas passes through a gas axial flow fan and a gas washing and dewatering device, and then is sent to a gas switching station, and the gas passing detection is sent to a gas tank.

[0011] Further, the outlet temperature of the vaporization cooling flue is 750-850 DEG C, the high-quality heat in the raw gas is recovered efficiently after the raw gas passes through the high-efficiency heat exchanger, and the temperature of the raw gas is reduced to 600 DEG C and enters the banana bend dust collector, and the banana bend dust collector is provided with a plurality of baffles. The inlet and outlet of the banana bend dust collector are axially extended and have an included angle to make the airflow direction change by 180 DEG, so as to facilitate the collection of coarse dust.

[0012] Further, the water-cooled chain conveyor is connected with an ash discharging pipe, the ash discharging pipe is provided with a pneumatic three-way discharge valve, a normal pneumatic double flap valve and an emergency pneumatic double flap valve;

[0013] The water-cooled chain conveyor discharges ash to an intermediate ash bin through the pneumatic three-way discharge valve, the normal pneumatic double flap valve and a bucket elevator, and the intermediate ash bin is used to feed the converter;

[0014] The water-cooled chain conveyor discharges ash to a coarse ash bin through the pneumatic three-way discharge valve and the emergency pneumatic double flap valve, and the coarse ash bin is used to transport coarse ash to the intermediate ash bin through a vacuum suction truck or a bin pump.

[0015] Further, the cyclone heat recovery device is provided with a cyclone device and a heat recovery device, the raw gas can be effectively separated from coarse dust and heat exchange is enhanced after the raw gas passes through the cyclone, and the outlet of the cyclone heat recovery device is connected with a raw gas pipe. The side wall of the raw gas pipe is connected with a nitrogen dilution pipe, the nitrogen dilution pipe is provided with a pneumatic cut-off valve, and nitrogen is blown in at some nodes of the converter to improve safety performance.

[0016] Further, the high-temperature-resistant explosion-proof super-clean dust collector can be used in combination with two or more, the inlets of the dust collectors are connected with raw gas pipes, the gas outlets of the dust collectors are connected with clean gas pipes, the ash outlets of the dust collectors are connected with ash collecting pipes and bin pumps to transport ash to a fine ash bin, the dust collectors are provided with explosion relief valves, rappers, heating coils and heat preservation structures, and the high-temperature-resistant explosion-proof super-clean dust collectors are connected with cooling replacement fans through pipes.

[0017] Further, a silencer is arranged on the pipeline between the coal gas axial flow fan and the coal gas washing dehydrator, the coal gas washed and cooled by the coal gas washing dehydrator enters the coal gas switching station, a recovery cup valve is arranged on the pipeline of the qualified coal gas output by the coal gas switching station, a diffusion cup valve is arranged on the pipeline of the unqualified coal gas output by the coal gas switching station, and the unqualified coal gas is sent to the diffusion chimney for ignition and diffusion.

[0018] Further, the diffusion chimney is provided with a nitrogen injection pipe and a purge pipe on one side, the medium transported by the nitrogen injection pipe is medium-pressure nitrogen with a pressure of greater than or equal to 1.2 MPa, and the medium transported by the purge pipe is low-pressure nitrogen or saturated steam with a pressure of greater than or equal to 0.6 MPa.

[0019] The third-generation converter one-time dry dedusting system has the following beneficial effects:

[0020] 1. The traditional evaporative cooling water spraying is cancelled, the stubborn problem of easy scaling of evaporative cooling is solved, converter gas waste heat is fully recovered, the steam recovery amount per ton of steel is increased by more than 50 kg, and the system is more energy-saving.

[0021] 2. The traditional electrostatic precipitator process is cancelled, after the high-temperature-resistant explosion-proof ultra-clean dust collector process is adopted, the problem of system explosion caused by frequent discharge of the equipment is solved, the system is safer, and the outlet concentration of the high-temperature-resistant explosion-proof ultra-clean dust collector can be maintained at 5 mg / Nm 3 The system is more environmentally friendly.

[0022] 3. The third-generation converter one-time dry dedusting system not only solves the problem of no recovery of high-quality heat, but also solves the problem of easy explosion of the dry dedusting system, and solves the problem of large fluctuation of the outlet emission concentration of the diffusion chimney, and is especially suitable for converter one-time flue gas dry dedusting projects, and has a wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0023] The utility model will be described further in combination with the drawings and examples, and the drawings are as follows:

[0024] Figure 1 is a structural schematic view of the third-generation converter one-time dry dedusting system of the utility model.

[0025] Figure 2 is Figure 1 a local part A enlarged view.

[0026] Figure 3 is Figure 1 a local part B enlarged view and a corresponding pipeline and fine ash bin, cooling replacement fan connection schematic view.

[0027] Figure 4 is Figure 1 a local part C enlarged view. DETAILED DESCRIPTION

[0028] The utility model will be further described below in combination with the drawings:

[0029] Embodiment: please refer to Figures 1 to 4 The third generation converter one dry method dust removal system of the utility model includes high efficiency heat exchanger 3, banana bend dust catcher 4, cyclone heat recovery device 5, water cooling chain conveyor 6, pneumatic tee unloading valve 7, normal pneumatic double flap valve 8, normal ash removal pipe 9, bucket elevator 10, intermediate ash bin 11, emergency pneumatic double flap valve 12, emergency ash removal pipe 13, coarse ash bin 14, nitrogen dilution pipe 15, pneumatic switching valve 16, raw coal gas pipe 17, high-temperature explosion-proof ultra-clean dust catcher 18, rapping device 19, heating coil 20, explosion relief valve 21, heat preservation structure 22, bin pump 23, pneumatic conveying pipeline, namely dust collecting pipe 24, fine ash bin 25, cooling replacement fan 26, clean coal gas pipe 27, coal gas axial flow fan 28, silencer 29, coal gas washing dehydrator 30, recovery cup valve 31, diffusion cup valve 33, diffusion chimney 34, nitrogen injection pipe 35 and purge pipe 36;The outlet of converter 1 is connected with vaporization cooling flue 2;

[0030] Converter 1 and high efficiency heat exchanger 3 are connected through vaporization cooling flue 2, and banana bend dust catcher 4 is arranged between high efficiency heat exchanger 3 and cyclone heat recovery device 5;High efficiency heat exchanger 3 is internally provided with heat exchange dense row pipe, and the high-quality heat in converter gas is taken away through heat exchange, thereby reducing the temperature of converter gas;

[0031] Banana bend dust catcher 4 is internally provided with multiple layers of baffle plates, can increase the residence time of dust-containing converter gas in banana bend dust catcher 4, and improve the dust removal efficiency;Banana bend dust catcher 4 is internally provided with multiple layers of baffle plates, can increase the residence time of dust-containing converter gas in banana bend dust catcher 4, and improve the dust removal efficiency;Banana bend dust catcher 4 is internally provided with multiple layers of baffle plates, can increase the residence time of dust-containing converter gas in banana bend dust catcher 4, and improve the dust removal efficiency;Banana bend dust catcher 4 is internally provided with multiple layers of baffle plates, can increase the residence time of dust-containing converter gas in banana bend dust catcher 4, and improve the dust removal efficiency;

[0032] Cyclone heat recovery device 5 is internally provided with cyclone device and heat recovery device;Raw coal gas can be effectively separated from coarse particle dust after cyclone, and heat exchange is strengthened, which is conducive to heat recovery;

[0033] Pneumatic tee unloading valve 7, normal pneumatic double flap valve 8 and emergency pneumatic double flap valve 12 are arranged on the ash removal pipe of water cooling chain conveyor 6;

[0034] Water cooling chain conveyor 6 is normally discharged to intermediate ash bin 11 through pipeline, pneumatic tee unloading valve 7, normal pneumatic double flap valve 8 and bucket elevator 10, and intermediate ash bin 11 is fed to converter 1;

[0035] The water-cooling chain conveyor 6 is connected with the pneumatic three-way discharge valve 7 and the emergency pneumatic double-layer flap valve 12, and the coarse ash bin 14 is connected with the vacuum suction truck and the bin pump.

[0036] The cyclone heat recovery device 5 and the high-temperature-resistant explosion-proof super-clean dust collector 18 are connected through the raw coal gas pipe 17; the cyclone heat recovery device 5 is connected with two, three, four or more high-temperature-resistant explosion-proof super-clean dust collectors 18, and the actual number is set according to the installation requirement; the gas outlets of the super-clean dust collectors are connected to output clean coal gas;

[0037] The high-temperature-resistant explosion-proof super-clean dust collector 18 is provided with a blow-off valve 21, a rapping device 19, a heating coil 20 and a heat preservation structure 22, and the heat preservation structure can be a heat preservation layer made of heat preservation material;

[0038] The high-temperature-resistant explosion-proof super-clean dust collector 18 is provided with a cooling replacement fan 26; once the dust collector is overhauled, the nitrogen replacement gas is passed, and the cooling replacement fan 26 is started to blow air into the dust collector cylinder, so as to play a role of cooling and ventilation;

[0039] The high-temperature-resistant explosion-proof super-clean dust collector 18 is provided with a cooling replacement fan 26; once the dust collector is overhauled, the nitrogen replacement gas is passed, and the cooling replacement fan 26 is started to blow air into the dust collector cylinder, so as to play a role of cooling and ventilation;

[0040] The high-temperature-resistant explosion-proof super-clean dust collector 18 is provided with a cooling replacement fan 26; once the dust collector is overhauled, the nitrogen replacement gas is passed, and the cooling replacement fan 26 is started to blow air into the dust collector cylinder, so as to play a role of cooling and ventilation;

[0041] The nitrogen dilution pipe 15 is provided with a pneumatic cut-off valve 16;

[0042] The nitrogen dilution pipe 15 is provided with a pneumatic cut-off valve 16;

[0043] The process flow of the third-generation converter one-time dry dust removal system in the utility model is as follows:

[0044] Converter 1→ vaporization cooling flue 2→ high-efficiency heat exchanger 3→ banana bend separator 4→ cyclone heat recovery device 5→ raw coal gas pipe 17→ high-temperature-resistant explosion-proof super-clean dust collector 18→ clean coal gas pipe 27→ coal gas axial flow fan 28→ silencer 29→ coal gas washing and dewatering device 30→ recovery cup valve 31 / dispersion cup valve 33→ coal gas tank 32 / dispersion chimney 34.

[0045] In the embodiment of the utility model, the temperature of the outlet of the reinforced vaporization cooling flue 2 is 750 DEG C ~ 850 DEG C (generally 800 DEG C), after the high-efficiency heat exchanger 3, the high-quality heat in the raw coal gas is recycled efficiently, and the temperature is reduced to 600 DEG C and enters the banana bend dust collector 4.

[0046] When the dust-containing raw coal gas passes through the banana bend dust collector 4, it first passes through the multilayer baffle collision, and due to the flow direction change of 180 DEG, under the action of gravity and centrifugal force, 35% ~ 45% (generally 40%) of the coarse particle dust is captured in the banana bend dust collector 4 and falls into the water-cooled chain conveyor 6.

[0047] The water-cooled chain conveyor 6 is horizontally arranged and is connected with the converter 1 process, and is periodically operated during smelting.

[0048] Under normal circumstances, the coarse ash collected by the water-cooled chain conveyor 6 in the utility model passes through the pneumatic three-way discharge valve 7 and the normal pneumatic double-layer flap valve 8 and enters the bucket elevator 10 through the normal ash discharge pipe 9, and the ash is discharged to the intermediate ash bin 11 by the bucket elevator 10; the intermediate ash bin 11 can store the coarse ash of two furnaces at most.

[0049] When the bucket elevator 10 is overhauled, the coarse ash collected by the water-cooled chain conveyor 6 passes through the pneumatic three-way discharge valve 7 and the emergency pneumatic double-layer flap valve 12 and is discharged to the coarse ash bin 14 through the emergency ash discharge pipe 13, and the coarse ash bin 14 transports the coarse ash to the intermediate ash bin 11 by the vacuum suction truck or by the warehouse pump.

[0050] The explosion venting valve 21 on the high-temperature explosion-proof super-clean dust collector 18 is provided with three-stage explosion venting, once the pressure in the high-temperature explosion-proof super-clean dust collector 18 exceeds 6500Pa, the explosion venting valve 21 is started to release pressure, and the equipment and system safety are protected; once the temperature in the dust collector is lower than 100 DEG C, the heating coil 20 works and stops working when the temperature is heated to 120 DEG C.

[0051] The qualified converter gas enters the coal gas washing and dewatering device 30, and after saturated water spraying cooling, the temperature is reduced from 150 DEG C to below 70 DEG C, so that the gas tank 32 can store more converter gas.

[0052] In the embodiment of the utility model, at the initial stage of converter blowing and after secondary lance lowering, the pneumatic cut-off valve 16 is opened, the nitrogen dilution pipe 15 sprays nitrogen for 30S, which is used for diluting the converter gas in the raw coal gas pipe 17 and preventing the content of the converter gas and oxygen from reaching the explosion limit.

[0053] In the embodiment of the utility model, once the system is powered off or the coal gas axial flow fan 28 fails, the pneumatic cut-off valve on the nitrogen injection pipe 35 is opened, nitrogen injection is performed for 15S, and the system safety is ensured.

[0054] The utility model discloses when using, the converter gas is by the diffusion cutback, opens the pneumatic cut valve on the blowing pipe 36, nitrogen or steam blowing 30S, prevents the diffusion chimney 34 backfire.

[0055] In one embodiment of the utility model, the diameter of the high-temperature-resistant explosion-proof super-clean dust collector 18 is 1.0-10 m, and two or more can be combined and used in parallel, the inlets of the dust collectors are connected to the raw gas pipes, the gas outlets of the dust collectors are connected to the clean gas pipes, and the ash outlets of the dust collectors are connected to the fine ash bins through the ash collecting pipes; the filter material of the high-temperature-resistant explosion-proof super-clean dust collector 18 is stainless steel, fluorine or P84; the filter material of the super-clean dust collector can also be aramid fiber ≥20% and aramid fiber ≥20% or anti-static glass fiber film filter material, and the content of stainless steel conductive fiber silk is ≥6%; the dust concentration at the outlet of the high-temperature-resistant explosion-proof super-clean dust collector 18 is ≤5 mg / Nm 3 The third-generation converter one-time dry-method dust removal system is suitable for 50t-400t converters, and the converter is defined as a decarburization converter, a dephosphorization converter, a vanadium extraction converter, a lava homogenizing furnace or a stainless steel converter.

[0056] The above-mentioned is only for the embodiment of the application, and any modification or change made by those skilled in the art using the application falls within the scope of the application, and is not limited to the embodiments disclosed.

Claims

1. A third generation top gas once-through dry dusting system, characterized by: The high-efficiency heat exchanger, the banana bend dust collector, the cyclone heat recovery device, the water-cooled chain conveyor, the raw gas pipe, the high-temperature-resistant explosion-proof super-clean dust collector, the fine ash bin, the clean gas pipe, the gas axial flow fan and the gas washing dehydrator are provided. The inlet of the high-efficiency heat exchanger is connected with the converter through the vaporization cooling flue, the raw gas of the converter is introduced into the high-efficiency heat exchanger to perform heat exchange and recovery, the banana bend dust collector is arranged between the high-efficiency heat exchanger and the cyclone heat recovery device, the water-cooled chain conveyor is arranged at the bottom of the banana bend dust collector, and the water-cooled chain conveyor is used to collect and output the coarse ash. The cyclone heat recovery device is connected with at least one high-temperature-resistant explosion-proof super-clean dust collector through the raw gas pipe, and the outlet of the high-temperature-resistant explosion-proof super-clean dust collector outputs clean gas. The outlet of the high-temperature-resistant explosion-proof super-clean dust collector is connected with the clean gas pipe, the clean gas passes through the gas axial flow fan and the gas washing dehydrator and is then sent to the gas switching station, and the qualified gas is sent to the gas tank.

2. The third generation dry dusting system for a converter as claimed in claim 1, wherein: The outlet temperature of the vaporization cooling flue is 750-850 DEG C, the high-quality heat in the raw gas is recovered efficiently after the raw gas passes through the high-efficiency heat exchanger, the temperature of the raw gas is reduced to 600 DEG C and the raw gas enters the banana bend dust collector, and the banana bend dust collector is provided with a plurality of baffle plates.

3. The third generation dry dusting system for a converter as claimed in claim 1, wherein: The inlet and outlet of the banana bend dust collector are axially extended and have an included angle, so that the direction of the gas flow is turned by 180 DEG.

4. The third generation dry dusting system for ladle once according to one of claims 1 to 3, characterized in that: The water-cooled chain conveyor is connected with the ash discharge pipe, the ash discharge pipe is provided with a pneumatic three-way discharge valve, a normal pneumatic double flap valve and an emergency pneumatic double flap valve. The water-cooled chain conveyor discharges the ash to the intermediate ash bin through the pneumatic three-way discharge valve, the normal pneumatic double flap valve and the bucket elevator, and the intermediate ash bin is used to feed the converter. The water-cooled chain conveyor discharges the ash to the coarse ash bin through the pneumatic three-way discharge valve, the emergency pneumatic double flap valve and the bucket elevator, and the coarse ash bin is used to discharge the coarse ash through the vacuum suction truck or to transport the coarse ash to the intermediate ash bin through the bin pump.

5. The third generation dry dusting system for a converter as claimed in claim 1, wherein: The cyclone heat recovery device is provided with a cyclone device and a heat recovery device, the raw gas is effectively separated from the coarse particles and dust after the cyclone, and the heat exchange is enhanced, and the outlet of the cyclone heat recovery device is connected with the raw gas pipe.

6. The third generation dry dusting system for once-through conversion of a converter according to claim 1 or 5, characterized in that: The sidewall of the raw gas pipe is connected with the nitrogen dilution pipe, and the nitrogen dilution pipe is provided with a pneumatic cut-off valve.

7. The third generation dry dusting system for a converter as claimed in claim 1, wherein: The high-temperature-resistant explosion-proof super-clean dust collector is provided with two or more combined dust collectors, the inlets of the dust collectors are connected with the raw gas pipe, the outlets of the dust collectors are connected with the clean gas pipe, the ash outlets of the dust collectors are connected with the ash collecting pipe and are used to discharge the ash to the fine ash bin, the dust collectors are provided with explosion relief valves, and the high-temperature-resistant explosion-proof super-clean dust collectors are connected with the cooling replacement fan through the pipeline.

8. The third generation dry dusting system for once converter according to claim 1 or 7, characterized in that: One side of the high-temperature-resistant explosion-proof super-clean dust collector is provided with a rapping device, and the dust collector is provided with a heating coil.

9. The third generation dry dusting system for once-through conversion of a converter as claimed in claim 1, characterized in that: A silencer is arranged on the pipeline between the gas axial flow fan and the gas switching station, a recovery cup valve is arranged on the pipeline of the qualified gas output by the gas switching station, and a diffusion cup valve is arranged on the pipeline of the unqualified gas output by the gas switching station.

10. The third generation dry dust extraction system for a converter as claimed in claim 1 or 2 or 3 or 5 or 7 or 9, wherein: One side of the diffusion chimney is provided with a nitrogen injection pipe and a blowing pipe, the medium transported by the nitrogen injection pipe is medium-pressure nitrogen with a pressure of greater than or equal to 1.2 MPa, and the medium transported by the blowing pipe is low-pressure nitrogen or saturated steam with a pressure of greater than or equal to 0.6 MPa.

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