CN2455729Y - High temperature hot blast stove for blast furnace - Google Patents
High temperature hot blast stove for blast furnace Download PDFInfo
- Publication number
- CN2455729Y CN2455729Y CN 00238795 CN00238795U CN2455729Y CN 2455729 Y CN2455729 Y CN 2455729Y CN 00238795 CN00238795 CN 00238795 CN 00238795 U CN00238795 U CN 00238795U CN 2455729 Y CN2455729 Y CN 2455729Y
- Authority
- CN
- China
- Prior art keywords
- regenerator
- heat
- hotblast stove
- accumulating
- temperature
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000007246 mechanism Effects 0.000 claims abstract description 22
- 238000002485 combustion reaction Methods 0.000 claims description 69
- 239000007789 gas Substances 0.000 claims description 21
- 238000005338 heat storage Methods 0.000 claims description 15
- 239000000919 ceramic Substances 0.000 claims description 8
- 239000000779 smoke Substances 0.000 claims description 8
- 238000007599 discharging Methods 0.000 claims description 5
- 238000000926 separation method Methods 0.000 claims description 4
- 239000002912 waste gas Substances 0.000 claims description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 2
- 239000000463 material Substances 0.000 claims description 2
- 238000009825 accumulation Methods 0.000 abstract description 9
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 22
- 239000003546 flue gas Substances 0.000 description 22
- 239000003034 coal gas Substances 0.000 description 12
- 239000000446 fuel Substances 0.000 description 6
- 208000011580 syndromic disease Diseases 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 4
- 238000003723 Smelting Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008676 import Effects 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Abstract
The utility model relates to a high temperature hot wind furnace for a blast furnace. A pair of high efficiency heat accumulating type auxiliary burners is arranged on the outside of a main burning chamber of a hot air furnace body. The high efficiency heat accumulating type auxiliary burners are composed of at least two sets of heat accumulating chambers or eat accumulation type burners, reversing mechanisms, high temperature valves, high temperature pipelines, blowers and draught fans. The high efficiency heat accumulating type auxiliary burners has the structural form that each set of heat accumulating chambers is composed of two divided heat accumulating chambers or two divided heat accumulation type burners; one end of each heat accumulating chamber is communicated with a main burning chamber of the hot wind furnace through a high temperature pipeline which is provided with a high temperature valve; the other end of each divided heat accumulating chamber or each divided accumulation type burner is communicated with one end of a reversing mechanism through a pipeline, and the other end of the reversing mechanism is communicated with a combustion-supporting air pipeline, a gas pipeline, a blower and a draught fan.
Description
The utility model belongs to the hotblast stove utility appliance that metallurgical iron-smelting blast furnace uses.
Iron-smelting blast furnace must infeed the high temperature combustion air by hotblast stove can finish the chemical reaction that reduction of iron ore is become the pig iron.Existing blast funnace hot blast stove is done fuel in the burning phase with the self-produced blast furnace gas of blast furnace, in the hotblast stove internal combustion and heat heat storage in its stove.Because the calorific value of blast furnace gas is lower, the flame temperature after the burning is relative also lower, and heated heat storage can't reach comparatively high temps.Therefore the hot blast temperature of hotblast stove confession outside on air is generally at 900～1050 ℃.The iron-smelting blast furnace hot blast temperature is an important factor, improves the multinomial technical indicator that this temperature can obviously improve blast furnace, and economic benefit is very remarkable.The conventional method that improves the blast funnace hot blast stove hot blast temperature had in the burning phase to be used than higher calorific value fuel, or adopts the method for heat exchanger preheated air or coal gas, improves flue-gas temperature and improves hot blast temperature.Because Combustion of Hot Air Furnace phase coal gas and combustion air consumption are very big, the volume of heat exchanger must be very huge, and investment is high, and effectiveness of heat exchanger is lower, and it is not obvious to improve hot blast temperature.
The purpose of this utility model is to propose a kind of high-air temp hot-blast stove for blast furnace technical scheme, use the used coal gas and the combustion air of portion of hot smoke pre-heating assisted combustion device of hotblast stove primary chamber, produce more pyritous flue gas after the burning, improve the hotblast stove regenerator temperature.Thereby improve the wind pushing temperature of hotblast stove, improve the fuel consumption of furnace processor and reduction blast furnace to blast furnace.
High-air temp hot-blast stove for blast furnace of the present utility model comprises the hot blast body of heater, and the high-efficiency heat-accumulating assisted combustion device is set outside the primary chamber of hot blast body of heater.Described high-efficiency heat-accumulating assisted combustion device comprises regenerator, high-temperature pipe, high temperature valve, reversing mechanism etc.High-efficiency heat-accumulating assisted combustion device one end is by pipeline and reversing mechanism UNICOM, and the other end is by the primary chamber UNICOM of high temperature valve and high-temperature pipe and hotblast stove; Its structural form can be that every group of regenerator is made up of regenerator or two heat-accumulating burners of two separations, and regenerator one end is provided with high temperature valve by the primary chamber of high-temperature pipe UNICOM hotblast stove on high-temperature pipe; The regenerator the other end of each separation is by pipeline and reversing mechanism one end UNICOM, at the reversing mechanism the other end by pipeline and gas blower, induced draft fan UNICOM.The utility model can be provided with on the high-temperature pipe between regenerator and the high temperature valve and diffuse valve.Two regenerator or two heat-accumulating burners that the utility model is separated are respectively warm-up combustion-supporting air regenerator and preheating gas regenerator, at least two of the induced draft fans of the reversing mechanism the other end and smoke discharging pipe UNICOM, waste gas that is used to discharge the warm-up combustion-supporting air regenerator wherein, another is used to discharge the waste gas of preheating gas regenerator.The spherical ceramic heat storage body of filling in the regenerator, heat storage diameter 5-30mm, material is a high alumina, high siliceous.Two groups of regenerator of assisted combustion device described in the utility model can be arranged up and down on the hot blast body of heater, and are perhaps horizontally disposed.Hotblast stove described in the utility model can be internal combustion type or external combustion type, and combustion system can be that bottom burning type also can be a top ignition.High-efficiency heat-accumulating assisted combustion device described in the utility model also can be a heat-accumulating burner.
The high wind-warm syndrome technology of the utility model hotblast stove is the periodically conversion of working order that is made every group of high-efficiency heat-accumulating assisted combustion device by reversing mechanism; Its operation program is:
When assisted combustion device was worked, valve closes is opened, diffused to the high temperature valve of two groups of regenerator;
A condition: promptly the regenerator of first group heat accumulating type assisted combustion device is the accumulation of heat state, and the part high-temperature flue gas of hotblast stove primary chamber enters first group regenerator heating heat storage wherein, enters reversing mechanism then, enters atmosphere by induced draft fan; The regenerator that is second group heat accumulating type assisted combustion device simultaneously is a preheat mode, the combustion air of assisted combustion device and coal gas enter the preheating of second group regenerator, enter high-temperature pipe mixed firing then, generation is higher than the ultrahigh-temperature flue gas of flue-gas temperature in the hotblast stove primary chamber, enters the interior flue gas of hotblast stove primary chamber and primary chamber and mixes and improve its temperature;
The B state: the working order of above-mentioned two groups of regenerator is exchanged;
Above two states periodical exchange finished to the Combustion of Hot Air Furnace phase, closed two high temperature valves, opened and diffused valve, discharged residual hot blast.
The two states exchange cycle is 30 seconds to 300 seconds.
The outstanding substantive distinguishing features of the utility model is outside the primary chamber of hotblast stove assisted combustion device to be set, and utilizes the used combustion air and the coal gas of part high-temperature flue gas accumulation of heat preheating assisted combustion device of hotblast stove primary chamber; The utility model obvious improvement is to improve effectively the wind pushing temperature of hotblast stove, improves the fuel consumption of furnace processor and reduction blast furnace.
Embodiment of the present utility model is as shown in drawings:
Accompanying drawing 1 high wind-warm syndrome internal combustion type blast funnace hot blast stove system diagram
Accompanying drawing 2 high wind-warm syndrome external combustion type blast funnace hot blast stove system diagrams
Accompanying drawing 3 adopts the high-air temp hot-blast stove for blast furnace system diagram of heat-accumulating burner
Number in the figure is respectively: 1. hotblast stove primary chamber, 2. heat accumulating type assisted combustion device, 3. regenerator or heat-accumulating burner, 4. reversing mechanism, 5. high temperature valve, 6. ceramic heat storage body, 7. high-temperature pipe, 8. diffuse valve, 9. induced draft fan, 10. gas blower.
Technical solutions of the utility model are specified the primary chamber 1 outer high-efficiency heat-accumulating assisted combustion device 2 that is provided with of high-air temp hot-blast stove for blast furnace of the present utility model in conjunction with implementing accompanying drawing.High-efficiency heat-accumulating assisted combustion device 2 comprises regenerator or heat-accumulating burner 3, the spherical ceramic heat storage body 6 of filling in it.Arrange two groups of high-efficiency heat-accumulating assisted combustion devices 2 on primary chamber in the blast-furnace hot-air furnace body and the high-temperature flue gas passage 1 at interval.Each high-efficiency heat-accumulating assisted combustion device 2 one end is linked by cryogenic piping and reversing mechanism 4, and its other end is linked by high-temperature pipe 7 and hotblast stove primary chamber 1, high temperature valve 5 is installed on high-temperature pipe 7 and is diffused valve 8.Lay at least two regenerator or heat-accumulating burner 3 in each high-efficiency heat-accumulating assisted combustion device 2, be respectively applied for combustion air and the coal gas of preheating by high-efficiency heat-accumulating assisted combustion device 2.When an assisted combustion device 2 is in the preheated burning state, high-temperature pipe 7 plays the combustion chamber effect, coal gas of high temperature after ceramic heat storage body 6 preheatings and high temperature combustion air ejection regenerator or heat-accumulating burner 3 backs are converged and burns at this, and the flue gas that produces ultrahigh-temperature imports in the flue gas of hotblast stove main combusting system 1 generation.Another high-efficiency heat-accumulating assisted combustion device is in smoke evacuation accumulation of heat state simultaneously, the part high-temperature flue gas of hotblast stove primary chamber 1 sucks this high-efficiency heat-accumulating assisted combustion device 2 through high-temperature pipe 7, and the spherical ceramic heat storage body 6 in flow through respectively at least two regenerator or the heat-accumulating burner 3, the heat in its flue gas is absorbed by ceramic heat storage body 6.At least one high temperature valve 5 is installed on each high-temperature pipe 7 and is diffused valve 8.Reversing mechanism 4 the other ends link with gas line, combustion air pipeline and the smoke discharging pipe of said apparatus respectively.In the Combustion of Hot Air Furnace phase, the high temperature valve 5 on the high-temperature pipe 7 is opened, and diffuses valve 8 and closes.By reversing mechanism 4 make two high-efficiency heat-accumulating assisted combustion device 2 periodics be operated in accumulation of heat in the state of combustion.At hotblast stove on air, the high temperature valve 5 on the high-temperature pipe 7 is closed, and diffuses valve 8 and opens, and high-efficiency heat-accumulating assisted combustion device 2 is not worked.Diffuse valve 8 and open the hot blast that discharges residual heat in the pipelines and may leak from high temperature valve, assisted combustion device is shielded.
The effect of the spherical heat storage of placing in the regenerator 36 is the high-temperature flue gas waste heats that reclaim by the discharging of this device, is used for combustion air and the coal gas of preheating by this device.When high-efficiency heat-accumulating assisted combustion device 2 was in preheat mode, combustion air and gas temperature after this device preheating all can reach more than 1000 ℃.Do under the condition of fuel at the same blast furnace gas that uses, coal gas after this device preheating and combustion air burn in high-temperature pipe 7 and can produce flame temperature more than 2400 ℃, and be higher more than 1000 ℃ than the flame temperature of main combusting system.Mix in the flue gas of the ultrahigh-temperature that produces of device and the exhaust gases passes of high-temperature flue gas in hotblast stove that main combusting system produces thus, reach the purpose of raising flue-gas temperature and hot blast temperature.The heating demand of high-efficiency heat-accumulating assisted combustion device 2 is 10～40% of a main combusting system heating demand, and this per-cent changes according to the hot blast temperature improvement value.Use the utility model, use blast furnace gas to do fuel equally, the wind-warm syndrome of blast funnace hot blast stove can improve more than 100～400 ℃.
As shown in Figure 1, use processing method of the present utility model is in the Combustion of Hot Air Furnace phase, and the high temperature valve 5 on the high-temperature pipe 7 is opened, and diffuses valve 8 and closes, 2 work of high-efficiency heat-accumulating assisted combustion device.Under A condition, the regenerator or the heat-accumulating burner 3 of top high-efficiency heat-accumulating assisted combustion device 2 are in the preheated burning state.Combustion air and coal gas enter the regenerator or the heat-accumulating burner 3 of top high-efficiency heat-accumulating assisted combustion device 2 by pipeline separately through reversing mechanism 4, and are preheating to respectively more than 1000 ℃.High temperature combustion air after the preheating and coal gas are flowed through and are met in the high-temperature pipe 7 and burn, and produce the flue gas of ultrahigh-temperature, import then in the flue gas that hotblast stove main combusting system 1 produces, and mixed flue-gas temperature is enhanced 200～500 ℃.Meanwhile, the regenerator of bottom high-efficiency heat-accumulating assisted combustion device 2 or heat-accumulating burner 3 are in smoke evacuation accumulation of heat state.Be inhaled into the regenerator or the heat-accumulating burner 3 of bottom high-efficiency heat-accumulating assisted combustion device 2 by the part in the high-temperature flue gas of hotblast stove main combusting system generation, behind the ceramic heat storage body 6 of this flue gas flow in it, its flue gas heat more than 90% is absorbed by heat storage 6, enters atmosphere through flow through reversing mechanism 4 and induced draft fan 9 of cryogenic piping then.The change of working order is sent commutation instruction by reversing control system, and reversing mechanism 4 actions become the B state with the working order of two groups of regenerator or heat-accumulating burner 3 by A condition.Under the B state, the regenerator of top high-efficiency heat-accumulating assisted combustion device 2 or heat-accumulating burner 3 are in smoke evacuation accumulation of heat state, and the regenerator of bottom high-efficiency heat-accumulating assisted combustion device 2 or heat-accumulating burner 3 are in the preheated burning state.Said system working order periodic exchanges, and the work period can be 30～300 seconds.
Characteristics of the present utility model:
1. the utility model is auxiliary at former blast funnace hot blast stove increase at least two group high-efficiency heat-accumulatings Burner or heat-accumulating burner only use blast furnace gas, can be with the heat of blast funnace hot blast stove Air temperature improves 100～400 ℃.
2. the utility model adopts high-efficiency heat-accumulating assisted combustion device, regenerator or heat accumulating type Burner, changement and low temperature supplying, gas extraction system scheme make the high wind-warm syndrome of this utility model Hot-blast stove is distinguished with conventional hot-blast stove and is: the utility model does not need the higher thermal value of burning Coal gas, do not need huge sky, gas change heater yet. The utility model device volume is little Ingeniously, efficient height.
3. the flame temperature after the burning of high-efficiency heat-accumulating assisted combustion device is burnt than hot-blast stove master Flame temperature after system's burning can improve more than 1000 ℃. Can be according to user's requirement, The flow of controlling this partial fume can reach the purpose that improves hot blast temperature. General this part stream Amount is 10～40% of total exhaust gas volumn.
4. the utility model is applicable to various blast funnace hot blast stoves, comprise bottom burning type, top ignition and outside Burning type hot-air furnace.
Claims (8)
1, a kind of high-air temp hot-blast stove for blast furnace, comprise hot-blast furnace body, it is characterized in that being provided with outside the primary chamber of hot-blast furnace body the high-efficiency heat-accumulating assisted combustion device, described high-efficiency heat-accumulating assisted combustion device is made of at least two group regenerator or heat-accumulating burner, high-temperature pipe, high temperature valve; Described assisted combustion device one end is by cryogenic piping UNICOM gas reversing mechanism, and the other end is by the primary chamber of high temperature valve and high-temperature pipe UNICOM hotblast stove; Its structural form can be that every group of regenerator is made up of regenerator or two heat-accumulating burners of two separations, and regenerator one end is provided with high temperature valve by the primary chamber of high-temperature pipe UNICOM hotblast stove on high-temperature pipe; The regenerator the other end of each separation is by pipeline and gas reversing mechanism one end UNICOM, at reversing mechanism the other end UNICOM combustion air pipeline, gas line and smoke discharging pipe and gas blower, induced draft fan.
2, hotblast stove as claimed in claim 1 is characterized in that being provided with on the pipeline between regenerator and the high temperature valve and diffuses valve.
3, hotblast stove as claimed in claim 1, it is characterized in that the regenerator of separating is respectively warm-up combustion-supporting air regenerator and preheating gas regenerator, at least two of the induced draft fans of the reversing mechanism the other end and smoke discharging pipe UNICOM, waste gas that is used for discharge stream through the warm-up combustion-supporting air regenerator wherein, another is used for the waste gas of discharge stream through the preheating gas regenerator.
4, hotblast stove as claimed in claim 1 is characterized in that the spherical ceramic heat storage body of filling in the regenerator, heat storage diameter 5-30mm, and material is a high alumina, high siliceous.
5, hotblast stove as claimed in claim 1 is characterized in that two groups of regenerator of described assisted combustion device or heat-accumulating burner can arrange up and down on hot blast body of heater primary chamber, perhaps horizontally disposed.
6, hotblast stove as claimed in claim 1 is characterized in that the hotblast stove primary chamber can be internal combustion type or external combustion type.The main combusting system position can be top ignition or bottom burning type.
7, hotblast stove as claimed in claim 1 is characterized in that described regenerator can be regenerator or a pair of heat-accumulating burner of separating.
8, hotblast stove as claimed in claim 1 is characterized in that reversing mechanism can be at least one group of two five-way valves, or two-position three-way valve, or one group of shut-off valve independently.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 00238795 CN2455729Y (en) | 2000-06-20 | 2000-06-20 | High temperature hot blast stove for blast furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 00238795 CN2455729Y (en) | 2000-06-20 | 2000-06-20 | High temperature hot blast stove for blast furnace |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2455729Y true CN2455729Y (en) | 2001-10-24 |
Family
ID=33599781
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 00238795 Expired - Lifetime CN2455729Y (en) | 2000-06-20 | 2000-06-20 | High temperature hot blast stove for blast furnace |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2455729Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108036665A (en) * | 2017-12-29 | 2018-05-15 | 中钢集团鞍山热能研究院有限公司 | Carbon baking furnace flue gas pollutant thermal accumulating incinerator and its processing method |
-
2000
- 2000-06-20 CN CN 00238795 patent/CN2455729Y/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108036665A (en) * | 2017-12-29 | 2018-05-15 | 中钢集团鞍山热能研究院有限公司 | Carbon baking furnace flue gas pollutant thermal accumulating incinerator and its processing method |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee |
Owner name: BEIDAONENGYUAN COMPANY, NO. 1, GUANZHUANG TOWNSHIP Free format text: FORMER NAME OR ADDRESS: A-106, ROME GARDEN, NO. 18, HUIXIN STREET(WEST), CHAOYANG DISTRICT, BEIJINGCITY, 100029 |
|
| CP03 | Change of name, title or address |
Patentee address after: 100024 North Island energy company, No. 1, Guanzhuang Township, Chaoyang District, Beijing Patentee address before: 100029, Rome garden, No. 18, Huixin West Street, Beijing, Chaoyang District A-106 |
|
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20000620 |
|
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20000620 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |