CN1144848A - Whole-dry type dust removing device and method for blast furnace gas - Google Patents
Whole-dry type dust removing device and method for blast furnace gas Download PDFInfo
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- CN1144848A CN1144848A CN 96109756 CN96109756A CN1144848A CN 1144848 A CN1144848 A CN 1144848A CN 96109756 CN96109756 CN 96109756 CN 96109756 A CN96109756 A CN 96109756A CN 1144848 A CN1144848 A CN 1144848A
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Abstract
A full-dry dusting method for the gas generated by blast furnace, converter, electric furnace and gas containing dust features that its duster is screen filtering one with filter core made of porous sintered metal wire net and there are two such dusters, which work alternatively. The duster not working uses back flushing system to clean its filter core. Its advantages include no need of cooling system, only need of simple heater, and high thermal efficiency and filter efficiency.
Description
The invention belongs to the filtration art that is used for gaseous fluid.Be mainly used in the purification of blast furnace gas, also be applicable to converter, electric furnace, producer gas and other high temperature dust gas cleaning.
Domestic and international existing blast furnace gas dry gas cleaning method roughly is divided into two kinds: i.e. cloth bag dust removal by filtration and dry type static dust.Cloth bag dust collection method is to be filtering element with the cloth bag, its main drawback be the permission use temperature of cloth bag below 300 ℃, be generally about 200 ℃, and the temperature out of blast furnace gas is usually above 400 ℃.Therefore, the complicated humidity control system of essential configuration when bag-type dust removal system uses, as water smoke directly spray, external cooling indirect heat exchange etc., otherwise will cause the scaling loss of cloth bag to destroy.And, even gas temperature is controlled in below 300 ℃, after cloth bag uses for some time, because frequent reverse gas cleaning.Also must cause the wearing and tearing of cloth bag, resistance is increased, flow reduces, the periodic replacement of having to.In case the run-down damage of cloth bag, it detects also very difficult at present automatically, and artificial regularly the detection then wasted time and energy, and be also dangerous, the destruction that certainly will cause the dust-removal system job stability.In addition, because cloth bag filter material intensity is low, be unsuitable for bearing higher filtration velocity.Thereby the filtration velocity that general bag-type dust removal system is adopted only is 0.5～1.0m/min, when the processing air quantity is higher, the volume of dust-removal system and floor space are just very huge, make its maintenance management expense very high (" blast furnace gas cloth bag dedusting and pebble stove technology and development ", 1991, high definition act, Tu Jiwei chief editor).The dry type static dust method is a kind of method for dust removal according to the electrostatic precipitation principle.Chinese patent ZL91102494.8 provides a kind of blast furnace gas fully-dried type electrostatic dust removing method.This method is to make blast furnace gas after the gravitational precipitator dedusting, by the heat exchange snubber, enters dry electrostatic cleaner again, and coal gas is purified.The shortcoming of this method for dust removal is: dust-removal system is huge, complex structure, and the initial cost height, current consumption is big, complex operation.And, for the works better that guarantees electrostatic precipitation system with reach higher efficiency of dust collection complicated coal gas humidification and cooling system must be set.When furnace top gas temperature surpasses the allowable temperature of electrostatic precipitation or is lower than the coal gas dew-point temperature, come strict control and regulate temperature of gas by the heat exchange snubber; When the coal gas voltage of electric field is lower than required value, must carry out the coal gas humidification from gravitational precipitator or an amount of steam or the water smoke of the feeding of the pipeline before and after it, to reduce the ratio resistance value of dust, improve the voltage of electric field of coal gas.
In a word, no matter blast furnace gas is to adopt the cloth bag dry gas cleaning, still adopts the static dry gas cleaning, and the humidification or the cooling system of strict control all must be set.The control difficulty that it has improved dust-removal system has on the one hand increased the complicacy of facility investment and system architecture; The reduction of gas temperature and humidity increase on the other hand, also are unfavorable for the effective utilization of gas heat and the raising of calorific value, will cause the huge waste of the energy.
The object of the present invention is to provide a kind of energy-conservation, water saving efficiency is high, non-environmental-pollution can be in stable operation under the high wind speed, and is applicable to the blast furnace gas fully-dried type cleaning apparatus and the method for dust removal of various operating modes.
At above-mentioned purpose, the present invention has adopted following technical scheme:
Blast furnace gas fully-dried type cleaning apparatus of the present invention contains raw gas pipe, gravitational precipitator or tornado dust collector, wire cloth filter collector, turbine generators, cleans tower, Combustion of Hot Air Furnace chamber, hotblast stove, well heater, blowback cleaning system, corresponding gas pipeline and various valve; Above-mentioned each equipment or parts interconnect by gas pipeline and various valve.Gravitational precipitator links to each other with the blast furnace furnace roof, and the blowback cleaning system directly links to each other with the wire cloth filter collector, and heater cartridge fits over coal gas and enters on the wire cloth filter collector pipeline before.
The wire cloth filter collector is to be the silk screen filter canister type extractor of filter core with the sintered metal mesh porous material, this wire cloth filter core is by after the stack of two-layer above wire cloth intersection, through sintering, rolling, be shaped, be welded, have intensity height, high temperature resistant even pore distribution, advantage such as the little and ability that sees through of circulating resistance is big.The blowback cleaning system is made up of nitrogen or purification gas holder, flowrate control valve and impulse electromagnetic valve.And have two or more wire cloth filter collectors in this cleaning apparatus at least, can switch use, non-stop run with the filter collector that guarantees dust-removal system.
The technical process of blast furnace gas fully-dried type method for dust removal of the present invention is as follows: top gas after pipeline enters the wire cloth filter collector, carries out filtration, purification to coal gas through gravitational precipitator or the elementary dedusting of tornado dust collector.High pressure blast furnace gas after the purification is through pipeline and variable valve, enter turbine, generate electricity, by the heating gas of turbine and the heating gas after the purification of normal pressure blast furnace, the one, deliver to the Combustion of Hot Air Furnace chamber as geseous fuel through pipeline, the one, through clean tower cooler, and after removing chlorion, deliver to gas line, use as other users.
For being higher than any high temperature blast furnace gas of dew-point temperature after gravitational precipitator or the elementary dedusting of tornado dust collector, can directly enter the wire cloth filter collector through pipeline, do not need to handle through any cooling.
When the temperature of blast furnace gas is lower than dew-point temperature, heater, the combustion exhaust of hotblast stove enters in the well heater by pipeline valve, by well heater blast furnace (BF) gas heating is heated up, and then enters the wire cloth filter collector.
Method for dust removal of the present invention is two or more wire cloth filter collectors (8,9) switch operatings in turn
Can utilize the blowback cleaning system for out-of-work wire cloth filter collector, the filter core of fly-ash separator is cleaned, remove the laying dust of cartridge surface etc.Usually, when the import and export coal gas pressure reduction of in running order wire cloth filter collector is higher than a certain prescribed value when (or surpassing a certain regulation work period), then close gas inlet, outlet valve, with the import and the outlet valve that advance to open another wire cloth filter collector, open flowrate control valve, the impulse electromagnetic valve of blowback cleaning system subsequently, make the nitrogen in nitrogen or the purification gas holder or purify coal gas, with the wire cloth filter collector of form by stopping of pulse, the laying dust of cartridge surface is cleaned up.
Cleaning apparatus of the present invention and method for dust removal are not only applicable to blast furnace gas purification, are applicable to electric furnace, converter and producer gas yet, and the purification of high temperature dusty gas such as boiler smoke, make it regeneration.
Compared with prior art, the present invention has following advantage:
(1), since blast furnace gas fully-dried type of the present invention purify adopted resistant to elevated temperatures, be the fly-ash separator of filter core with the sintered metal mesh porous material, working temperature can be up to 300～800 ℃, so purify the gas temperature height, calorific value is big, can improve the heating efficiency of turbine generating efficiency and hotblast stove greatly.
(2), the heating gas scavenging process need not the cooling, so saved complicated water smoke spraying cooling cooling system, not only reduced the consumption of the big water gaging and the energy, saved investment and floor space, and the saving;
(3), sintered metal mesh porous material filter core, intensity height, running resistance are little, technological process is reliable, efficiency of dust collection is greater than 99.9%, can be under higher filtration velocity steady operation;
(4), whole dust-removal system is simple in structure, Operation and maintenance are convenient, and the fly-ash separator filter core can regenerate, long service life, cost is low.
(5), when the wire cloth filter collector adopts higher filtration velocity (1～60m/min), still can protect carrying out smoothly and purification efficiency stable of technological process.
Now the invention will be further described in conjunction with the accompanying drawings.
Accompanying drawing 1 is the structural representation of blast furnace gas fully-dried type cleaning apparatus of the present invention and the schematic flow sheet of method for dust removal.
Find out by Fig. 1, blast furnace gas fully-dried type cleaning apparatus of the present invention is by raw gas pipe 2, gravitational precipitator 3 or tornado dust collector 4, pipeline 39 and well heater 5, wire cloth filter collector 8,9 and glasses valve 6,7 and valve 10,11, turbine 14, relief valve 18 and glasses valve 13 and valve 12,15,16, pipeline 17,19,20, clean tower 24 and pipeline 21,22, valve 25 and purification gas line 26, Combustion of Hot Air Furnace chamber 29, hotblast stove 30 and glasses valve 28, valve 27, pipeline valve 32, nitrogen or purification gas holder 35 and flowrate control valve 36 and impulse electromagnetic valve 37,38 form.
Wherein the wire cloth filter collector the 8, the 9th, is the fly-ash separator of filter core with the sintered metal mesh porous material; Well heater 5 is assemblied in coal gas and enters on wire cloth filter collector 8,9 pipeline 39 before; Form the blowback cleaning system by nitrogen or purification gas holder 35, flowrate control valve 36 and impulse electromagnetic valve 37,38.
The technical process of blast furnace gas fully-dried type method for dust removal of the present invention is as follows:
First kind of technical process: for the high pressure blast furnace gas with top pressure power generation equipment, the stock gas that is produced by blast furnace 1 is under standard state, through raw gas pipe 2, to gravitational precipitator 3, through tornado dust collector 4, enter fly-ash separator 8 again, carry out gas purification by glasses valve 6; Part purifies coal gas through valve 10,12 and glasses valve 13, enter turbine 14, carry out top pressure power generation, purify coal gas afterwards and arrive thermal purification gas line 20,21,, enter Combustion of Hot Air Furnace chamber 29 through valve 27 and glasses valve 28 through valve 15, burn, and in hotblast stove 30, carry out sensible heat utilization, waste gas after burning is through hot-blast stove flue 33, by chimney 34 emptying; Another part thermal purification coal gas carries out sensible heat utilization through valve 23 to other heating or boiler; Remaining thermal purification coal gas is removed chlorion after valve 25 enters and purifies gas line 26 by clean tower 24 coolings, uses as him.When stock gas is instantaneous when being lower than the coal gas dew point, opening conduits valve 32 makes hotblast stove 30 combustion exhaust enter well heater 5, makes ducted coal gas heat temperature raising, and then enters wire cloth filter collector 8.
Second kind of technical process: for the normal pressure blast furnace that does not have top pressure power generation equipment, its technical process is compared with first kind of technical process, can cancel gravitational precipitator 3 or tornado dust collector 4, there are not valve 12,13 and turbine 14, and increase valve 16, pressure regulation 18 and pipeline 19, make by the coal gas after 8,9 purifications of wire cloth filter collector, after relief valve 18 step-downs, enter corresponding pipeline and utilized, promptly identical with the rear section of first kind of technical process.
In above-mentioned technical process, state when 8 work of wire cloth filter collector, then wire cloth filter collector 9 is in the state of quitting work, and both take turns to operate.Usually, when the import and export coal gas pressure reduction of in running order wire cloth filter collector 8 is higher than a certain prescribed value, or after surpassing a certain regulation work period, then close this fly-ash separator 8, open another fly-ash separator 9 simultaneously.Carry out blowback for fly-ash separator out of service 8 and clean, promptly open flowrate control valve 36, impulse electromagnetic valve 37, make the nitrogen in the storage tank 35 or purify coal gas to enter wire cloth filter collector 8, clean the cartridge surface laying dust, recover best-of-breed functionality.
Claims (6)
1, a kind of blast furnace gas fully-dried type cleaning apparatus, comprise raw gas pipe (2), gravitational precipitator (3) or tornado dust collector (4), fly-ash separator (8,9), turbine generators (14), clean tower (24), Combustion of Hot Air Furnace chamber (29) and hotblast stove (30), corresponding gas pipeline and various valve, it is characterized in that:
[1], fly-ash separator (8,9) is to be the silk screen filter fly-ash separator of filter core with the sintered metal mesh porous material;
[2], contain one by nitrogen or purify gas holder (35), flowrate control valve (36) links to each other with wire cloth filter collector (8,9) with this blowback cleaning system of filter core blowback cleaning system that impulse electromagnetic valve (37,38) is formed;
[3], enter wire cloth filter collector (8,9) pipeline (39) before at coal gas and go up configuration simple heating device (5).
2, cleaning apparatus according to claim 1 is characterized in that being provided with at least two or more wire cloth filter collectors (8,9).
3, a kind of blast furnace gas fully-dried type method for dust removal that utilizes the described cleaning apparatus of claim 1, comprise top gas after gravitational precipitator (3) or the elementary dedusting of tornado dust collector (4), enter the silk screen filter fly-ash separator through pipeline (39), coal gas is purified, high pressure blast furnace gas after the purification is through pipeline and variable valve, enter turbine (14), generate electricity, by the heating gas of turbine (14) and the heating gas after the purification of normal pressure blast furnace, the one, deliver to blast furnace and hot blast cupola combustion chamber (29) as geseous fuel through pipeline; The one, after cleaning tower (24) cooling, removing chlorion, send into gas line (25), use for other user, it is characterized in that:
[1], for any high temperature blast furnace gas that is higher than dew-point temperature, after gravitational precipitator (3) or the elementary dedusting of tornado dust collector (4), can directly enter wire cloth filter collector (8,9), need not to handle through any cooling;
[2], when the temperature of blast furnace gas is lower than dew-point temperature, the combustion exhaust of heater (5), hotblast stove (30) is by pipeline valve (32), enter in the well heater (5), by well heater (5) blast furnace (BF) gas heating in the pipeline is heated up, and then enter wire cloth filter collector (8 or 9);
[3], two or more wire cloth filter collectors (8,9) can take turns switch operating;
[4], for out-of-work wire cloth filter collector (8 or 9), can utilize the blowback cleaning system, the filter core of wire cloth filter collector (8 or 9) is cleaned, remove the laying dust of cartridge surface, make filter core regeneration.
4, method for dust removal according to claim 3 is characterized in that making wire cloth filter collector (8 or 9) be in work or shut down condition by opening or closing eyes valve (6 or 7), valve (10 or 11).
5, according to claim 3 and 4 described method for dust removals, it is characterized in that import and export coal gas pressure reduction when in running order wire cloth filter collector (8 or 9) is higher than after a certain prescribed value or working hour surpass a certain set(ting)value, then close eyes valve (6 or 7) and valve (10 or 11), open eyes valve (7 or 6) and valve (11 or 10), and open flowrate control valve (36) and impulse electromagnetic valve (37 or 38), gas in nitrogen or the purification gas holder (35) is through flowrate control valve (36) and impulse electromagnetic valve (37 or 38), form with pulse is passed through wire cloth filter collector (8 or 9), and the laying dust of cartridge surface is cleaned up.
6, according to claim 1 and described cleaning apparatus of claim 3 and method for dust removal, the present invention is not only applicable to blast furnace gas purification, is applicable to electric furnace, converter and producer gas yet, and the purification of high temperature dusty gas such as boiler smoke.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 96109756 CN1144848A (en) | 1996-09-13 | 1996-09-13 | Whole-dry type dust removing device and method for blast furnace gas |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 96109756 CN1144848A (en) | 1996-09-13 | 1996-09-13 | Whole-dry type dust removing device and method for blast furnace gas |
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| CN1144848A true CN1144848A (en) | 1997-03-12 |
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| CN 96109756 Pending CN1144848A (en) | 1996-09-13 | 1996-09-13 | Whole-dry type dust removing device and method for blast furnace gas |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1131091C (en) * | 2000-07-07 | 2003-12-17 | 清华大学 | Filter material and filter for reverse spray to regenerate carbon smoke filter |
| CN101788486A (en) * | 2010-03-02 | 2010-07-28 | 武汉钢铁(集团)公司 | Flue gas on-line analysis device of converter hot end |
| CN101829459A (en) * | 2010-03-31 | 2010-09-15 | 楼生友 | Separation circulatory system for carbon dust |
| CN102423596A (en) * | 2011-09-06 | 2012-04-25 | 单文奎 | High-temperature dust remover |
| CN102434098A (en) * | 2011-12-01 | 2012-05-02 | 中国煤炭科工集团太原研究院 | Hydraulic five-arm anchor drill for coal mine |
| CN101352636B (en) * | 2007-07-25 | 2012-05-23 | 贾颖 | Technique for purifying converter gas and removing dust |
| CN102492492A (en) * | 2011-12-09 | 2012-06-13 | 上海安赐机械设备有限公司 | Device for processing coke oven gas by using reinforcement separation technology and proces thereof |
| CN102703628A (en) * | 2012-06-13 | 2012-10-03 | 北京首钢国际工程技术有限公司 | Use method for circulating comprehensive utilization device for blast furnace gas |
| CN103215400A (en) * | 2013-04-19 | 2013-07-24 | 成都瑞柯林工程技术有限公司 | Flue gas dust removal equipment with temperature fluctuation and flue gas dust removal system |
| CN104004550A (en) * | 2014-05-21 | 2014-08-27 | 河南龙成煤高效技术应用有限公司 | Purification and dust removal system of dusty coal gas and process method of purification and dust removal system |
| CN108115131A (en) * | 2016-11-30 | 2018-06-05 | 北京易加三维科技有限公司 | For the active blowback cleaning equipment of selective laser fusing manufacture |
| CN110846087A (en) * | 2019-12-20 | 2020-02-28 | 无锡伊诺特过滤系统有限公司 | Full-automatic filter and separation and filtration method |
| CN113046504A (en) * | 2021-03-18 | 2021-06-29 | 东北大学 | Blast furnace production system utilizing waste heat, residual pressure and residual cooling |
-
1996
- 1996-09-13 CN CN 96109756 patent/CN1144848A/en active Pending
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1131091C (en) * | 2000-07-07 | 2003-12-17 | 清华大学 | Filter material and filter for reverse spray to regenerate carbon smoke filter |
| CN101352636B (en) * | 2007-07-25 | 2012-05-23 | 贾颖 | Technique for purifying converter gas and removing dust |
| CN101788486A (en) * | 2010-03-02 | 2010-07-28 | 武汉钢铁(集团)公司 | Flue gas on-line analysis device of converter hot end |
| CN101829459B (en) * | 2010-03-31 | 2015-04-01 | 楼生友 | Separation circulatory system for carbon dust |
| CN101829459A (en) * | 2010-03-31 | 2010-09-15 | 楼生友 | Separation circulatory system for carbon dust |
| CN102423596A (en) * | 2011-09-06 | 2012-04-25 | 单文奎 | High-temperature dust remover |
| CN102423596B (en) * | 2011-09-06 | 2013-08-07 | 单文奎 | High-temperature dust remover |
| CN102434098A (en) * | 2011-12-01 | 2012-05-02 | 中国煤炭科工集团太原研究院 | Hydraulic five-arm anchor drill for coal mine |
| CN102434098B (en) * | 2011-12-01 | 2014-05-28 | 中国煤炭科工集团太原研究院 | Hydraulic five-arm anchor drill for coal mine |
| CN102492492A (en) * | 2011-12-09 | 2012-06-13 | 上海安赐机械设备有限公司 | Device for processing coke oven gas by using reinforcement separation technology and proces thereof |
| CN102703628A (en) * | 2012-06-13 | 2012-10-03 | 北京首钢国际工程技术有限公司 | Use method for circulating comprehensive utilization device for blast furnace gas |
| CN103215400A (en) * | 2013-04-19 | 2013-07-24 | 成都瑞柯林工程技术有限公司 | Flue gas dust removal equipment with temperature fluctuation and flue gas dust removal system |
| CN103215400B (en) * | 2013-04-19 | 2014-12-10 | 成都瑞柯林工程技术有限公司 | Flue gas dust removal equipment with temperature fluctuation and flue gas dust removal system |
| CN104004550A (en) * | 2014-05-21 | 2014-08-27 | 河南龙成煤高效技术应用有限公司 | Purification and dust removal system of dusty coal gas and process method of purification and dust removal system |
| CN108115131A (en) * | 2016-11-30 | 2018-06-05 | 北京易加三维科技有限公司 | For the active blowback cleaning equipment of selective laser fusing manufacture |
| CN110846087A (en) * | 2019-12-20 | 2020-02-28 | 无锡伊诺特过滤系统有限公司 | Full-automatic filter and separation and filtration method |
| CN113046504A (en) * | 2021-03-18 | 2021-06-29 | 东北大学 | Blast furnace production system utilizing waste heat, residual pressure and residual cooling |
| CN113046504B (en) * | 2021-03-18 | 2022-06-21 | 东北大学 | Blast furnace production system utilizing waste heat, residual pressure and residual cooling |
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