CN103509903B - Phase-change heat storage type high-air-temperature hot blast stove - Google Patents
Phase-change heat storage type high-air-temperature hot blast stove Download PDFInfo
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- CN103509903B CN103509903B CN201210205243.XA CN201210205243A CN103509903B CN 103509903 B CN103509903 B CN 103509903B CN 201210205243 A CN201210205243 A CN 201210205243A CN 103509903 B CN103509903 B CN 103509903B
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- 238000005338 heat storage Methods 0.000 title abstract description 5
- 238000004146 energy storage Methods 0.000 claims abstract description 64
- 239000011232 storage material Substances 0.000 claims abstract description 64
- 239000000779 smoke Substances 0.000 claims abstract description 16
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000003546 flue gas Substances 0.000 claims abstract description 9
- 239000011449 brick Substances 0.000 abstract description 19
- 238000005192 partition Methods 0.000 abstract 1
- 239000000463 material Substances 0.000 description 10
- 238000000034 method Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 7
- 208000011580 syndromic disease Diseases 0.000 description 7
- 230000009466 transformation Effects 0.000 description 7
- 235000019504 cigarettes Nutrition 0.000 description 5
- 238000002485 combustion reaction Methods 0.000 description 5
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000003723 Smelting Methods 0.000 description 2
- 230000001413 cellular effect Effects 0.000 description 2
- 239000003245 coal Substances 0.000 description 2
- 239000003034 coal gas Substances 0.000 description 2
- 230000009970 fire resistant effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 230000003245 working effect Effects 0.000 description 2
- 229910004283 SiO 4 Inorganic materials 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000004078 cryogenic material Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 239000007770 graphite material Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910017053 inorganic salt Inorganic materials 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000010310 metallurgical process Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000012782 phase change material Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
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- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
Abstract
The invention discloses a phase-change heat storage type high-air-temperature hot blast stove which comprises a hot blast main pipe, a cold blast main pipe, a temperature regulator and a smoke exhaust main pipe which are connected to a hot blast stove body, wherein a hot blast valve, a cold blast valve, a hot smoke valve and a smoke exhaust valve are respectively arranged on the hot blast main pipe, the cold blast main pipe, the temperature regulator and the smoke exhaust main pipe; the front of the hot smoke valve is connected with a burner, and the rear of the smoke exhaust valve is connected with a draught fan; the inner cavity of the furnace body is sequentially separated into a high-temperature energy storage material cavity, a medium-temperature energy storage material cavity and a low-temperature energy storage material cavity by a flow dividing partition plate with holes according to the flowing direction of flue gas; the energy storage material cavity is sequentially filled with a high-temperature energy storage material, a medium-temperature energy storage material and a low-temperature energy storage material. The hot blast stove capable of realizing the high-temperature stable air temperature reduces the volume of the hot blast stove by changing the checker bricks, reduces the consumption of the hot blast stove and provides stable high-temperature hot air for the blast furnace.
Description
Technical field
The invention belongs to metallurgical process ironmaking complementary energy and recycle field, particularly relate to a kind of phase-change thermal storage type high-blast-temperature hot-blast stove.
Background technology
Hotblast stove, as the important component part of Iron-smelting, for the smelting of blast furnace provides heat, realizes the target that stable high wind-warm syndrome is stove operation.Because existing blast funnace hot blast stove adopts traditional checker brick to be fire-resistant material, temperature resistant capability is limited, and wind-warm syndrome can not reach very high.Simultaneously its thermal conductivity, heat accumulation are subject to the physical properties limitation of resistance to material, need longer thermal storage time, in this process, because material is with the change of flue gas, air themperature, are difficult to realize stable high wind-warm syndrome.
Patent of invention " checker brick " (CN200880127503.8) discloses a kind of checker brick for hotblast stove, these checker brick have top surface and relative lower surface, wherein, multiple passage extends to lower surface from top surface, to make fluid pass checker brick flowing, between adjacency channel, be formed with spaced walls.According to an aspect of the present invention, passage has the cross section based on hexagonal shape, and this hexagonal shape has protrusion side alternately and concave side.This patent is started with from the rock steady structure of checker brick, extends hot blast through the time of checker brick simultaneously, strengthens its heat transfer process, but effectively can not improve hot blast temperature based on resistance to wood property matter.
Patent of invention " a kind of multiduty hotblast stove combustion air preheated in high temperature system " (CN201110006766.7) provides a kind of multiduty this system of hotblast stove combustion air preheated in high temperature system to can be applicable to blast furnace overhaul transformation project or hot blast stove system overhauls separately or transformation project or newly-built blast furnace project, preheating oven both can be blast furnace and provided high-temperature hot-air, can be again hotblast stove and high temperature preheating combustion air is provided, guarantee hotblast stove maintenance or transformation to be reduced to minimum on the impact that blast furnace produces., coal gas empty by preheated-combustion-supporting in early stage can improve hot blast temperature really effectively, but due to preheater consumed energy in early stage, simultaneously because its structure is less, inefficiency, adds the running cost of hotblast stove greatly.Simultaneously because the raising of temperature of combustion makes the temperature difference of the initial air feed of hotblast stove and end of a period air feed increase, be unfavorable for the production of blast furnace.
Utility model " porous cellular checker brick " (CN200720091293.4) discloses a kind of porous cellular checker brick, and it comprises brick body, brick body is offered porose, and its pore diameter range is
; Be respectively arranged with boss and groove at upper and lower two end faces of brick body, the boss of upper and lower two end faces and groove one_to_one corresponding, its medullary ray coincides.Namely significantly can promote heat exchange amount and the heat exchanger effectiveness of hotblast stove, heat-resistant knocking stability significantly strengthens, and is 30 years work-ing life, achieves blast funnace hot blast stove low cost movement, and energy-conservation good with environmental benefit.Honeycomb body structure is adopted to be used for hotblast stove, specific surface area can be increased to greatest extent, also reduce heat storage capacity largely simultaneously, make the commutation of hotblast stove frequent, reduce the life-span of reversing valve, reversing valve specification simultaneously due to hotblast stove is comparatively large, and commutation causes it to use power consumption significantly to improve frequently.
In sum, existing hotblast stove all have employed traditional fire-resistant material as heat transferring medium, have employed several mode, changing checker brick shape, improving the coefficient of heat transfer for improving hot blast temperature; Outer energizing quantity realizes the object of high wind-warm syndrome by the method for preheated-combustion-supporting sky, coal gas or oxygen-enriched combusting.But due to the temperature variation of checker brick in heat transfer process, cause initial air feed and latter stage air feed the temperature difference comparatively large, be unfavorable for the production of blast furnace.
Summary of the invention
In order to overcome the shortcoming of above-mentioned prior art, the invention provides a kind of hotblast stove that can realize stablizing high wind-warm syndrome, being reduced the volume of hotblast stove by the mode changing checker brick, reduce the consumption of hotblast stove, simultaneously for blast furnace provides stable high-temperature hot-air.
A kind of phase-change thermal storage type high-blast-temperature hot-blast stove, be included on hot-blast furnace body and connect hot-blast main, cold blast main, thermosistor and smoke evacuation house steward, it is characterized in that: body of heater inner chamber split-flow baffles with holes is separated out high temperature energy-storage materials chamber, middle temperature energy storage material chamber and Low-Grade Thermal-Energy Storage Material chamber successively by flow of flue gas direction; Filled high-temperature energy storage material, middle temperature energy storage material, Low-Grade Thermal-Energy Storage Material successively in energy storage material chamber.
Wherein, high temperature energy-storage material latent heat scope 900 ~ 1200 kJ/kg, middle temperature energy storage material latent heat scope 400 ~ 600 kJ/kg, Low-Grade Thermal-Energy Storage Material latent heat scope 200 ~ 400 kJ/kg.
The shape of energy storage material is divided into various ways, spherical, cylindrical, hexagonal cylindricality etc., by the air quantity of hotblast stove, and volume diameter ￠ 200 ~ ￠ 500mm of energy storage material.
The approximate aperture of sky (combustion) the air-flow through hole on split-flow baffles is ￠ 150 ~ ￠ 450mm.Shape, according to the shape of energy storage material, is divided into circle, square, sexangle etc.
Selection about high temperature, middle temperature, Low-Grade Thermal-Energy Storage Material sees the following form.
| High-temperature material | Middle adiabator | Cryogenic material | |
| Temperature range (DEG C) | 850~1250 | 400~900 | 200~500 |
| Material | Inorganic salt stupalith | Phase change materials | Graphite material |
| Latent heat scope (kJ/kg) | 900~1200 | 400~600 | 200~400 |
By the selection of above material, hotblast stove volume declines 20% ~ 50%, and hot blast temperature is stabilized in about 1200 DEG C, and funnel temperature is stabilized in less than 150 DEG C.
Energy storage material has high specific heat, high thermal conduction characteristic, temperature-resistant due in energy storage material phase transformation exothermic process, therefore can realize stable hot blast temperature, improve the efficiency of hotblast stove, be conducive to the stably manufactured realizing blast furnace; Simultaneously the heat storage capacity of energy storage material and heat-transfer capability are much larger than the tradition checker brick of resistance to material, and under identical hot blast rate, volume is much smaller than traditional checker brick, and hotblast stove volume can reduce, and realizes device miniaturization, reduces running cost; Hotblast stove lateral arrangement, that effectively reduces energy storage material self bears pressure, and the checker brick reduced in operational process are damaged, improve the work-ing life of hotblast stove.
Accompanying drawing explanation
Fig. 1 is phase-change thermal storage type Configuration in Hot Blast Stove with High Blast Temperature schematic diagram of the present invention;
1, burner; 2, thermosistor; 3, hot-blast main; 4, hot blast valve; 5, cold blast main; 6, cold blast valve; 7, induced draft fan; 8, exhaust smoke valve; 9, discharge fume house steward; 10, Low-Grade Thermal-Energy Storage Material chamber; 11, middle temperature energy storage material chamber; 12, high temperature energy-storage materials chamber; 13, split-flow baffles; 14, body of heater; 15, hot cigarette valve.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described:
As shown in Figure 1: phase-change thermal storage type high-blast-temperature hot-blast stove is included on hot-blast furnace body 14 and connects hot-blast main 3, cold blast main 5, thermosistor 2 and smoke evacuation house steward 9, arranges the hot blast valve 4 on it, cold blast valve 6, hot cigarette valve 15 and exhaust smoke valve 8 respectively; Connect burner 1 before hot cigarette valve 15, after exhaust smoke valve 8, connect induced draft fan 7; Body of heater 14 inner chamber 4 pieces of split-flow baffles 13 with holes are separated out high temperature energy-storage materials chamber 12, middle temperature energy storage material chamber 11 and Low-Grade Thermal-Energy Storage Material chamber 10 successively by flow of flue gas direction; Filled high-temperature energy storage material, middle temperature energy storage material, Low-Grade Thermal-Energy Storage Material successively in energy storage material chamber.
Embodiment 1
Hot blast rate 300000Nm
3the conventional hot blast stove of/h, evenly heat air temperature 1220 DEG C (temperature range is reduced to 1050 DEG C from 1250 DEG C (air feed initial stages)), its sensible heat is the 525753261.2kJ/ cycle.By not changing air feed cycle design.
When hotblast stove high temperature heat transfer efficiency is 20%, 30%, 50%, the heat that heat-storing sphere needs is 103270753 kJ/ cycles, 154906129 kJ/ cycles, 258176882 kJ/ cycles from low to high.All provided by the heat of phase transformation of energy storage material, then need MgF
2high temperature energy-storage material 198597.60kg, warm energy storage material 221294.47kg in LiOH, KOH Low-Grade Thermal-Energy Storage Material 258176.88kg, single heat-storing sphere diameter is 400mm, need bead 10920 (wherein high temperature 3212, middle temperature 3854, low temperature 3854, clapboard aperture is 350mm, and shape is circular, and whole chamber of hot-blast stove volume is 700m
3, and the regenerator volume of conventional hot blast stove is 1200m
3, reduce volume 42%.Simultaneously owing to all providing thermal source by heat of phase transformation, hot blast temperature is stabilized in 1250 DEG C in heat-exchange periodic.
Original hotblast stove is normally produced, and blast furnace coal tolerance need be provided to be 93500Nm
3/ h, thermo-efficiency reaches 65.5%.After adopting energy storage material new technology, it is 539878835.1 kJ/h that hot blast temperature is stabilized in 1250 DEG C of heats taken out of, and thermo-efficiency brings up to 68.5%.The wind-warm syndrome of Simultaneous Stabilization is advantageously in the operation of blast furnace.
Embodiment 2
Same hot blast rate 150000Nm
3the little hotblast stove of/h.Conventional hot blast stove evenly heat air temperature 1200 DEG C (temperature range is reduced to 1020 DEG C from 1230 DEG C (air feed initial stages)), its sensible heat is the 262876630.6kJ/ cycle.
Hotblast stove high temperature heat transfer efficiency is constant, remains 20%, 30%, 50%, and the heat that heat-storing sphere needs is 52575326.12 kJ/ cycles, 78862989.18 kJ/ cycles, 131438315.3 kJ/ cycles from low to high.All provided by the heat of phase transformation of energy storage material, select LiOH+LIF matrix material to be high temperature energy-storage material, need high temperature composite energy-storage material 111388.40kg, Na
2sO
4/ SiO
4middle temperature energy storage material 98578.74kg, NaNO
3low-Grade Thermal-Energy Storage Material 219063.86 kg, heat-storing material shape is hexagonal column, its equivalent diameter is 300mm, high 300mm, the length of side is 173mm, need heat storage 9174 pieces (wherein high temperature 2382 pieces, middle temperature 2108 pieces, low temperature 4684 pieces, dividing plate hole shape is hexagon, the length of side is 165mm, then the volume of whole chamber of hot-blast stove is 300 m
3, and the regenerator volume of conventional hot blast stove is 580 m
3, reduce volume 48%.Hot blast temperature is stabilized in 1220 DEG C
Original hotblast stove is normally produced, and blast furnace coal tolerance need be provided to be 52000Nm
3/ h, thermo-efficiency reaches 70%.After adopting energy storage material new technology, it is 262876630.6 kJ/h that hot blast temperature is stabilized in 1220 DEG C of heats taken out of, and thermo-efficiency brings up to 72.5%.The wind-warm syndrome of Simultaneous Stabilization is advantageously in the operation of blast furnace.
Heat-accumulating process: close cold blast valve 6 and hot blast valve 4.Open hot cigarette valve 15, exhaust smoke valve 8 and induced draft fan 7, burner 1 produces high-temperature flue gas, body of heater 14 is entered via thermosistor 2 pressurization, the cold wind adjustment of simultaneously being mixed by thermosistor 2 enters the flue-gas temperature of regenerator, distribute air-flow by split-flow baffles 13, heat high temperature energy-storage materials chamber 12, middle temperature energy storage material chamber 11, Low-Grade Thermal-Energy Storage Material chamber 10 successively afterwards.Energy storage material inside in chamber undergoes phase transition, and utilizes decalescence to be taken out of by the heat in flue gas, and is stored in storage bodies inside.The flue gas reducing temperature is discharged out of the furnace by induced draft fan 7 via smoke evacuation house steward 9 and exhaust smoke valve 8.
Exothermic process: close burner 1, hot cigarette valve 15, thermosistor 2, exhaust smoke valve 8 and induced draft fan 7.Open cold blast valve 6 and hot blast valve 4, freezing air enters body of heater via cold blast main 5, successively through low temperature, middle gentle high temperature energy-storage materials chamber 10,11 and 12, takes the heat in energy storage material out of, the material in chamber is undergone phase transition and solidifies.Hot blast after heating enters hot-blast main 3 via hot blast valve 4, supply blast furnace.Back and forth complete stove operation successively.
Claims (3)
1. a phase-change thermal storage type high-blast-temperature hot-blast stove, be included on hot-blast furnace body (14) and connect hot-blast main (3), cold blast main (5), thermosistor (2) and smoke evacuation house steward (9), it is characterized in that: hotblast stove lateral arrangement, body of heater (14) inner chamber split-flow baffles (13) with holes is separated out high temperature energy-storage materials chamber (12), middle temperature energy storage material chamber (11) and Low-Grade Thermal-Energy Storage Material chamber (10) successively by flow of flue gas direction; Filled high-temperature energy storage material, middle temperature energy storage material, Low-Grade Thermal-Energy Storage Material successively in energy storage material chamber; The volume diameter ￠ 200-￠ 500mm of energy storage material; Hole on described split-flow baffles (13) is the circular hole of equivalent diameter ￠ 150-￠ 450mm, square hole or hex hole.
2. phase-change thermal storage type high-blast-temperature hot-blast stove according to claim 1, is characterized in that described high temperature energy-storage material latent heat scope 900-1200Kj/Kg, middle temperature energy storage material latent heat scope 400-600Kj/Kg, Low-Grade Thermal-Energy Storage Material latent heat scope 200-400Kj/Kg.
3. phase-change thermal storage type high-blast-temperature hot-blast stove according to claim 1, is characterized in that the shape of described energy storage material is spherical, cylindrical or hexagonal cylindricality.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210205243.XA CN103509903B (en) | 2012-06-20 | 2012-06-20 | Phase-change heat storage type high-air-temperature hot blast stove |
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|---|---|---|---|
| CN201210205243.XA CN103509903B (en) | 2012-06-20 | 2012-06-20 | Phase-change heat storage type high-air-temperature hot blast stove |
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| CN103509903A CN103509903A (en) | 2014-01-15 |
| CN103509903B true CN103509903B (en) | 2015-09-02 |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1077276A (en) * | 1993-02-13 | 1993-10-13 | 阿尔斯特罗姆公司 | Be used for for example hot-blast stove of blast furnace air of preheated air |
| CN101892338A (en) * | 2010-07-22 | 2010-11-24 | 首钢总公司 | Constant wind temperature control system for hot blast stove |
| CN201873705U (en) * | 2010-11-26 | 2011-06-22 | 中冶赛迪工程技术股份有限公司 | Co-combustion type air heater |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04216777A (en) * | 1990-12-14 | 1992-08-06 | Nippon Mente Kaihatsu Kk | Injection method of concrete repair agent and injection plug |
-
2012
- 2012-06-20 CN CN201210205243.XA patent/CN103509903B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1077276A (en) * | 1993-02-13 | 1993-10-13 | 阿尔斯特罗姆公司 | Be used for for example hot-blast stove of blast furnace air of preheated air |
| CN101892338A (en) * | 2010-07-22 | 2010-11-24 | 首钢总公司 | Constant wind temperature control system for hot blast stove |
| CN201873705U (en) * | 2010-11-26 | 2011-06-22 | 中冶赛迪工程技术股份有限公司 | Co-combustion type air heater |
Non-Patent Citations (1)
| Title |
|---|
| 蓄热室新型蓄热体的研究进展;李爱菊等;《冶金能源》;20070531;第26卷(第3期);第2节第2段，第3节第4段 * |
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| CN103509903A (en) | 2014-01-15 |
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