CN101892345A - Converter coal gas dry-method dedusting system and using method thereof - Google Patents

Converter coal gas dry-method dedusting system and using method thereof Download PDF

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Publication number
CN101892345A
CN101892345A CN2010102407832A CN201010240783A CN101892345A CN 101892345 A CN101892345 A CN 101892345A CN 2010102407832 A CN2010102407832 A CN 2010102407832A CN 201010240783 A CN201010240783 A CN 201010240783A CN 101892345 A CN101892345 A CN 101892345A
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gas
coal gas
converter
cooling system
iron powder
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CN101892345B (en
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盖东兴
刘洁
邵远敬
纪世昌
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Wisdri Engineering and Research Incorporation Ltd
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Wisdri Engineering and Research Incorporation Ltd
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

Abstract

The invention provides a converter coal gas dry-method dedusting system and a using method thereof. The system comprises a coal gas cooling system and a deduster which are communicated, wherein the inlet of the coal gas cooling system is connected to a converter; the deduster is connected to the inlet of a switching station through a draught fan; the outlet of the switching station is connected to a diffusing chimney and a coal gas cooler respectively; a coarse dust collection device is arranged at the position of a banana bend at the tail end of the coal gas cooling system; a fine dust collection device is arranged at the bottom of the deduster; the coarse and fine dust collected by the coarse/fine dust collection devices are briquetted into briquettes by a dust briquetting device; the briquettes are used as raw materials for steeling making in the converter; the coal gas cooling system is provided with a coal gas component analyser; and a reduced iron powder injection device and an electromagnetic device are arranged in a pipe section between the coal gas cooling system and the deduster in turn. In the invention, the safety of the converter coal gas dry-method dedusting system is improved, and the recovery rate of Converter coal gas is improved, and energy conservation and environment protection are realized.

Description

Converter gas dry-dedusting system and using method thereof
Technical field
The present invention relates to converter gas dry-dedusting system.
Background technology
Converter generates a large amount of high-temperature flue gas in process of production, and wherein major ingredients is CO, CO 2, O 2, N 2With Ar etc., and the gas-entrained FeO, the Fe that go out 2O 3, CaO, SiO 2In dust, its total dustiness is 80-150g/Nm 3, must be with it cooling dedusting, the one ton of steel that blows can reclaim the coal gas of converter 80-120Nm that contains CO concentration 60% 3Converter coal gas purification and recovery system mainly are divided into now: gas dry-dedusting system and wet gas cleaning system.
Converter gas dry-dedusting system all has bigger superiority in economy and environmental protection.The major advantage that dry method is compared with wet method: the one, udst separation efficient height, the dust mass concentration is reduced to 10mg/Nm 3Below; The 2nd, this system all adopts dry process, does not have secondary pollution and sewage disposal, reclaims dust and can directly utilize, and has saved water consumption; The 3rd, system's resistance is decreased little, has reduced energy consumption; The 4th, system simplification, floor space is little, is convenient to administer and maintain.
Traditional converter gas dry-dedusting system is in coal gas is in the limits of explosion scope time, venting of dust explosion can take place in the electrostatic precipitator, usually little blast is released pressure of explosion by 6~8 explosion venting valves, if blast has surpassed the pressure release ability of explosion venting valve, then will damage even demolish electrostatic precipitator and cause industrial accident.
Summary of the invention
Technical problem to be solved by this invention is: a kind of converter gas dry-dedusting system and using method thereof are provided, and the present invention can improve the security of converter gas dry-dedusting system, can also improve the rate of recovery of coal gas of converter, energy-conserving and environment-protective.
The technical solution adopted in the present invention is: converter gas dry-dedusting system comprises gas cooling system and the fly-ash separator that is connected, the inlet of gas cooling system is connected to converter, fly-ash separator is connected to the inlet of switching station by induced draft fan, the outlet of switching station is connected to respectively diffuses chimney and gas chamber, meal dirt collection device is equipped with in the tail end banana crook of gas cooling system, the fine dust collection device is equipped with in the fly-ash separator bottom, slightly/that the fine dust collection device is collected is thick, fine dust is by dust briquetting equipment briquetting, as the converter steelmaking raw material, gas cooling system is provided with the gas composition analyser, and the pipeline section between gas cooling system and the fly-ash separator is provided with reduced iron powder jetting device and electromagnet apparatus successively.
The using method of converter gas dry-dedusting system: converter produces coal gas, and during by gas cooling system, whether the gas composition analyser detects coal gas and be in the huge explosion scope, and detects it and whether reach recovering condition; If the gas composition analyser detects coal gas in explosive range, then according to the quality of coal gas oxygen level by the reduced iron powder that calculates needs and spray into, the reduced iron powder jetting device sprays into pipeline between evaporative cooler and the electrostatic precipitator by nitrogen with iron powder, simultaneously, avoid unreacted iron powder to enter electrostatic precipitator and influence its performance at the electrostatic precipitator pre-installed electromagnet apparatus that enters the mouth; The coal gas that meets recovering condition through electrostatic precipitator, gas cooler cooling dedusting, is collected in the gas chamber more at last, and the coal gas that does not meet recovering condition is lighted and diffused by diffusing chimney; If induced draft fan has a power failure or breaks down in converting process, coal gas switches to by switching station and diffuses chimney, by the high pressure nitrogen induction apparatus coal gas is lighted and is diffused from diffusing chimney again.
Advantage of the present invention: the security that has 1. fundamentally solved converter gas dry-dedusting system; 2. improve the rate of recovery of coal gas of converter.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Among the figure, 1: converter; 2: the oxygen rifle; 3: gasification cooling flue; 4: steam pockets; 5: the gas composition analyser; 6: double-flow spray gun; 7: evaporative cooler; 8: meal dirt collection device; 9: electrostatic precipitator; 10: the fine dust collection device; 11: induced draft fan; 12: switching station; 13: diffuse chimney; 14: spray gun; 15: gas cooler; 16: gas chamber; 17: dust briquetting equipment; 18: the high pressure nitrogen induction apparatus; 19: the reduced iron powder jetting device; 20: electromagnet apparatus.
Embodiment
As Fig. 1, converter gas dry-dedusting system, comprise the gas cooling system and the fly-ash separator that are connected, the inlet of gas cooling system is connected to converter 1, fly-ash separator is connected to the inlet of switching station 12 by induced draft fan 11, the outlet of switching station 12 is connected to respectively diffuses chimney 13 and gas chamber 16, meal dirt collection device 8 is equipped with in the tail end banana crook of gas cooling system, fine dust collection device 10 is equipped with in the fly-ash separator bottom, slightly/that the fine dust collection device is collected is thick, fine dust is by dust briquetting equipment 17 briquettings, as the converter steelmaking raw material, gas cooling system is provided with gas composition analyser 5, and the pipeline section between gas cooling system and the fly-ash separator is provided with reduced iron powder jetting device 19 and electromagnet apparatus 20 successively.
In preferred embodiment, gas cooling system comprises gasification cooling flue 3 and the evaporative cooler 7 that is connected, and described gas composition analyser 5 is arranged on the afterbody of gasification cooling flue 3.
In preferred embodiment, fly-ash separator adopts electrostatic precipitator 9.
In preferred embodiment, reduced iron powder jetting device 19 is arranged on the pipeline section between evaporative cooler 7 and the electrostatic precipitator 9, and electromagnet apparatus 20 is arranged on electrostatic precipitator 9 ingress.
In preferred embodiment, diffuse chimney 13 and be provided with induction apparatus.
In preferred embodiment, induction apparatus adopts high pressure nitrogen induction apparatus 18.
In preferred embodiment, also be connected to gas cooler 15 between switching station 12 and the gas chamber 16.
As shown in Figure 1, aerobic rifle 2 in the converter 1, the top of gasification cooling flue 3 is provided with steam pockets 4, and the ingress of evaporative cooler 7 is provided with double-flow spray gun 6, and gas cooler 15 is provided with spray gun 14.
The using method of converter gas dry-dedusting system: converter 1 produces coal gas, and during by gas cooling system, whether gas composition analyser 5 detects coal gas and be in the huge explosion scope, and detects it and whether reach recovering condition; If gas composition analyser 5 detects coal gas in explosive range, then according to the quality of coal gas oxygen level by the reduced iron powder that calculates needs and spray into, reduced iron powder jetting device 19 sprays into pipeline between evaporative cooler 7 and the electrostatic precipitator 9 by nitrogen with iron powder, simultaneously at the pre-installed electromagnet apparatus 20 of electrostatic precipitator 9 inlets, avoid unreacted iron powder to enter electrostatic precipitator 9 and influence its performance; The coal gas that meets recovering condition through electrostatic precipitator 9, gas cooler 15 cooling dedustings, is collected in the gas chamber 16 more at last, and the coal gas that does not meet recovering condition is lighted and diffused by diffusing chimney 13; If induced draft fan 11 has a power failure or breaks down in converting process, coal gas switches to by switching station 12 and diffuses chimney 13, by high pressure nitrogen induction apparatus 18 coal gas is lighted and is diffused from diffusing chimney 13 again.
Detailed operation process of the present invention mainly comprises following steps: 1) gasification cooling flue 3 is reduced to 800~1100 ℃ with coal gas for about 1600 ℃ from the converter mouth; 2) the gas composition analyser 5 that is contained in gasification cooling flue 3 tops is monitored each components contents in the coal gas in real time, judges whether it is in the limits of explosion scope; 3) coal gas further is reduced to 200~250 ℃ by evaporative cooler 7 temperature, and there is 30~40% cinder dirt to collect in evaporative cooler 7 bottoms, and the water and steam that double-flow spray gun 6 sprays into has reduced the ratio resistance of dust, makes the working range of its suitable electrostatic precipitator 9; 4) if coal gas is in the explosive range, then the pipeline between evaporative cooler 7 and electrostatic precipitator 9 sprays into reduced iron powder by reduced iron powder jetting device 19, the straying quatity of reduced iron powder is calculated by the coal gas oxygen level, reduced iron powder is sprayed into by nitrogen, and it sprays into a little setting by the time lag of gas composition analyser 5 and the decision of flow of gas speed; 5), avoid not oxidized reduced iron powder to enter electrostatic precipitator 9 and influence its performance at the pre-installed electromagnet apparatus 20 of electrostatic precipitator 9 inlet; 6) electrostatic precipitator 9 is reduced to 10mg/Nm with dust concentration 37) will reach the purification coal gas of recovering condition, it be imported after gas cooler 15 is chilled to 70~80 ℃, coal gas will be stored in gas chamber 16 by switching station 12; 8) coal gas that will not reach recovering condition is lighted and is diffused by diffusing chimney 13; 9) in the steelmaking process if induced draft fan 11 disorderly closedowns, then intrasystem coal gas is imported and diffuses chimney 13 by high pressure nitrogen induction apparatus 18, burning is diffused.The present invention has improved the rate of recovery of coal gas of converter by a simple method, has avoided coal gas to be in the explosive range simultaneously electrostatic precipitator 9 is produced destruction.
In order to understand the present invention better, below sets forth in detail content of the present invention.
1) whether gas composition analyser 5 composition that detects coal gas is in the limits of explosion scope; Detect coal gas simultaneously and whether reach recovering condition.
2) if coal gas is in outside the limits of explosion scope, then coal gas is by gasification cooling flue 3, electrostatic precipitator 9 cooling dedustings, if coal gas satisfies recovering condition simultaneously, then switching station imports coal gas and is sent to gas chamber 16 after gas cooler 15 is chilled to 70~80 ℃; If coal gas does not satisfy recovering condition, then switching station 12 imports coal gas and diffuses chimney 13, lights and diffuses.
3) if coal gas is in the limits of explosion scope, then calculate the amount that needs add reduced iron powder, thereby the oxide compound that the reduced iron powder that reduced iron powder jetting device 19 sprays into will generate iron with oxygen generation chemical reaction is reduced to the oxygen level in the coal gas beyond the explosive range according to coal gas total amount and coal gas oxygen level.Reduced iron powder can absorb airborne oxygen and water vapour, so there is special nitrogen seal device that it and air is isolated, and it is sprayed into pipeline between evaporative cooler 7 and the electrostatic precipitator 9 by high pressure nitrogen, spray into setting velocity of flow decision in pipeline a little by time of lag of gas composition analyser 5 and coal gas, far away apart from gas composition analyser 5 as much as possible.
4) before electrostatic precipitator 9 inlet, electromagnet apparatus 20 is installed, with unreacted iron powder sucking-off in order to avoid influence the performance of electrostatic precipitator 9.The reduced iron powder that electromagnet apparatus 20 absorbs needs cleaning timely, in order to avoid react and cause accident at non-steel-making stage and inhaled air.The purge mode of electromagnet apparatus 20 is summarized as follows: spray into after the reduced iron powder at every turn, finish first few minutes at this heat, with the electro-magnet degaussing, by rapping apparatus iron powder is shaken down, by double-deck flap valve iron powder has been fallen into nitrogen-sealed container then.
5) will be in beyond the limits of explosion scope, through the reacted coal gas of reduced iron powder according to step 2) handle.
When 6) induced draft fan 11 broke down in the converting process, oxygen rifle 2 was carried in converter 1 immediately, by diffusing the high pressure nitrogen induction apparatus 18 of chimney 13 bottoms, coal gas injection residual in the dust-removal system to diffusing chimney 13, was lighted and was diffused.
In order to understand the present invention better, further illustrate content of the present invention below in conjunction with embodiment, but content of the present invention not only is confined to following example.
Embodiment 1: the mixed gas that produces in converter 1 converting process is in explosive range, and its counter-measure step is as follows:
1) gas composition analyser 5 detects the composition of coal gas, judges it in limits of explosion;
2), calculate the amount of oxygen that needs removal, thereby calculate the iron powder amount that the unit time need spray into according to each gas component ratio and total gas flow;
When 3) coal gas in being in limits of explosion arrives reduced iron powder jetting device 19, iron powder is sprayed into by the certain quality flow by high pressure nitrogen; Beyond the coal gas through reduced iron powder jetting device 19 is in limits of explosion, stop to spray into iron powder;
4) reach the coal gas of recovering condition, by switching station 12 it is imported gas cooler 15 and be cooled to 70~80 ℃, at last coal gas is stored in gas chamber 16;
5) do not reach the coal gas of recovering condition, import by switching station 12 and diffuse chimney 13 and light and diffuse;
6) this heat finishes 2min or just finishing blowing before, and electromagnet apparatus 20 degaussings are shaken iron powder down by rapping apparatus, by double-deck flap valve iron powder have been fallen into nitrogen-sealed container then, avoid contacting for a long time with air.
Thus, be in limits of explosion with interior mixed gas even converter has produced, oxygen content be reduced to beyond the limits of explosion scope, just can avoid taking place in the electric precipitation venting of dust explosion by spraying into reduced iron powder, thereby guarantee the safety of converter gas dry-dedusting system, and can increase the rate of recovery of coal gas.

Claims (8)

1. converter gas dry-dedusting system, comprise the gas cooling system and the fly-ash separator that are connected, the inlet of gas cooling system is connected to converter (1), fly-ash separator is connected to the inlet of switching station (12) by induced draft fan (11), the outlet of switching station (12) is connected to respectively diffuses chimney (13) and gas chamber (16), meal dirt collection device (8) is equipped with in the tail end banana crook of gas cooling system, fine dust collection device (10) is equipped with in the fly-ash separator bottom, slightly/that the fine dust collection device is collected is thick, fine dust is by dust briquetting equipment (17) briquetting, as the converter steelmaking raw material, it is characterized in that: gas cooling system is provided with gas composition analyser (5), and the pipeline section between gas cooling system and the fly-ash separator is provided with reduced iron powder jetting device (19) and electromagnet apparatus (20) successively.
2. dust-removal system according to claim 1 is characterized in that: gas cooling system comprises gasification cooling flue (3) and the evaporative cooler (7) that is connected, and described gas composition analyser (5) is arranged on the afterbody of gasification cooling flue (3).
3. dust-removal system according to claim 1 is characterized in that: fly-ash separator adopts electrostatic precipitator (9).
4. dust-removal system according to claim 1 is characterized in that: diffuse chimney (13) and be provided with induction apparatus.
5. dust-removal system according to claim 4 is characterized in that: induction apparatus adopts high pressure nitrogen induction apparatus (18).
6. according to each described dust-removal system in the claim 1~5, it is characterized in that: also be connected to gas cooler (15) between switching station (12) and the gas chamber (16).
7. according to claim 2 or 3 described dust-removal systems, it is characterized in that: reduced iron powder jetting device (19) and electromagnet apparatus (20) are set between evaporative cooler (7) and the electrostatic precipitator (9).
8. the using method of converter gas dry-dedusting system is characterized in that: converter (1) produces coal gas, and during by gas cooling system, whether gas composition analyser (5) detects coal gas and be in the huge explosion scope, and detects it and whether reach recovering condition; If gas composition analyser (5) detects coal gas in explosive range, then according to the quality of coal gas oxygen level by the reduced iron powder that calculates needs and spray into, reduced iron powder jetting device (19) sprays into pipeline between evaporative cooler (7) and the electrostatic precipitator (9) by nitrogen with iron powder, simultaneously at electrostatic precipitator (9) the pre-installed electromagnet apparatus (20) that enters the mouth, avoid unreacted iron powder to enter electrostatic precipitator (9) and influence its performance; The coal gas that meets recovering condition through electrostatic precipitator (9), gas cooler (15) cooling dedusting, is collected in the gas chamber (16) more at last, and the coal gas that does not meet recovering condition is lighted and diffused by diffusing chimney (13); If induced draft fan (11) has a power failure or break down in converting process, coal gas switches to by switching station (12) and diffuses chimney (13), by high pressure nitrogen induction apparatus (18) coal gas is lighted and is diffused from diffusing chimney (13) again.
CN2010102407832A 2010-07-30 2010-07-30 Converter coal gas dry-method dedusting system and using method thereof Active CN101892345B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102382934A (en) * 2011-10-31 2012-03-21 中冶南方工程技术有限公司 Converter primary flue gas dry dedusting system

Citations (4)

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Publication number Priority date Publication date Assignee Title
JPS61257409A (en) * 1985-05-09 1986-11-14 Nippon Steel Corp Closed operating method for converter gas treatment device
CN101550466A (en) * 2008-03-31 2009-10-07 上海宝钢工程技术有限公司 Converter coal gas high-temperature bag-type dust removing system
CN101570808A (en) * 2009-05-31 2009-11-04 中冶京诚工程技术有限公司 Dry converter coal gas dust-removal system and explosion protection device thereof
CN201857402U (en) * 2010-07-30 2011-06-08 中冶南方工程技术有限公司 Dry dust removing system for converter gas

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61257409A (en) * 1985-05-09 1986-11-14 Nippon Steel Corp Closed operating method for converter gas treatment device
CN101550466A (en) * 2008-03-31 2009-10-07 上海宝钢工程技术有限公司 Converter coal gas high-temperature bag-type dust removing system
CN101570808A (en) * 2009-05-31 2009-11-04 中冶京诚工程技术有限公司 Dry converter coal gas dust-removal system and explosion protection device thereof
CN201857402U (en) * 2010-07-30 2011-06-08 中冶南方工程技术有限公司 Dry dust removing system for converter gas

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《钢铁研究》 19960930 吴 东 篱 转炉L T 干法除尘系统 7-14 1-8 , 第5期 2 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102382934A (en) * 2011-10-31 2012-03-21 中冶南方工程技术有限公司 Converter primary flue gas dry dedusting system

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