CN103553669B - Method for preparing Sialon material inside blast furnace - Google Patents
Method for preparing Sialon material inside blast furnace Download PDFInfo
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- CN103553669B CN103553669B CN201310509414.2A CN201310509414A CN103553669B CN 103553669 B CN103553669 B CN 103553669B CN 201310509414 A CN201310509414 A CN 201310509414A CN 103553669 B CN103553669 B CN 103553669B
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- 239000000463 material Substances 0.000 title claims abstract description 119
- 238000000034 method Methods 0.000 title abstract description 20
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 186
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 94
- 238000010276 construction Methods 0.000 claims abstract description 65
- 238000002360 preparation method Methods 0.000 claims abstract description 22
- 239000000843 powder Substances 0.000 claims description 42
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 37
- 229910052710 silicon Inorganic materials 0.000 claims description 32
- 229910052799 carbon Inorganic materials 0.000 claims description 30
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 21
- 229910000838 Al alloy Inorganic materials 0.000 claims description 20
- 230000008676 import Effects 0.000 claims description 20
- 239000010703 silicon Substances 0.000 claims description 20
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 15
- 229910052782 aluminium Inorganic materials 0.000 claims description 13
- 239000004035 construction material Substances 0.000 claims description 13
- 230000015572 biosynthetic process Effects 0.000 claims description 12
- 239000004927 clay Substances 0.000 claims description 12
- 229910001404 rare earth metal oxide Inorganic materials 0.000 claims description 12
- 239000011819 refractory material Substances 0.000 claims description 11
- 229920001617 Vinyon Polymers 0.000 claims description 10
- 239000007789 gas Substances 0.000 claims description 10
- 229910052760 oxygen Inorganic materials 0.000 claims description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 9
- 239000001301 oxygen Substances 0.000 claims description 9
- 238000009628 steelmaking Methods 0.000 claims description 8
- 238000010926 purge Methods 0.000 claims description 6
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000002184 metal Substances 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 abstract description 11
- 238000004519 manufacturing process Methods 0.000 abstract description 11
- 239000010959 steel Substances 0.000 abstract description 11
- 230000008901 benefit Effects 0.000 abstract description 5
- 239000002699 waste material Substances 0.000 abstract 4
- 238000003825 pressing Methods 0.000 abstract 2
- 238000004079 fireproofing Methods 0.000 abstract 1
- 238000003754 machining Methods 0.000 abstract 1
- 230000002035 prolonged effect Effects 0.000 abstract 1
- 238000007789 sealing Methods 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 18
- 239000011449 brick Substances 0.000 description 14
- 238000009413 insulation Methods 0.000 description 12
- 239000000919 ceramic Substances 0.000 description 9
- 239000003595 mist Substances 0.000 description 7
- 239000012299 nitrogen atmosphere Substances 0.000 description 7
- UXBZSSBXGPYSIL-UHFFFAOYSA-N phosphoric acid;yttrium(3+) Chemical compound [Y+3].OP(O)(O)=O UXBZSSBXGPYSIL-UHFFFAOYSA-N 0.000 description 7
- 229920001083 polybutene Polymers 0.000 description 7
- 238000005507 spraying Methods 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 229910000164 yttrium(III) phosphate Inorganic materials 0.000 description 7
- -1 5 parts Substances 0.000 description 6
- 239000004709 Chlorinated polyethylene Substances 0.000 description 6
- 238000003303 reheating Methods 0.000 description 6
- 238000003786 synthesis reaction Methods 0.000 description 6
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 5
- 239000012466 permeate Substances 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 239000007921 spray Substances 0.000 description 5
- 239000004698 Polyethylene Substances 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 229920000573 polyethylene Polymers 0.000 description 4
- 238000004873 anchoring Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000003034 coal gas Substances 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 229910052593 corundum Inorganic materials 0.000 description 2
- 239000010431 corundum Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052761 rare earth metal Inorganic materials 0.000 description 2
- 150000002910 rare earth metals Chemical class 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920002554 vinyl polymer Polymers 0.000 description 2
- 230000003245 working effect Effects 0.000 description 2
- QGZKDVFQNNGYKY-OUBTZVSYSA-N Ammonia-15N Chemical compound [15NH3] QGZKDVFQNNGYKY-OUBTZVSYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910052684 Cerium Inorganic materials 0.000 description 1
- 229910052693 Europium Inorganic materials 0.000 description 1
- 229910052688 Gadolinium Inorganic materials 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 229910052777 Praseodymium Inorganic materials 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000009970 fire resistant effect Effects 0.000 description 1
- 239000005338 frosted glass Substances 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000005121 nitriding Methods 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 208000011580 syndromic disease Diseases 0.000 description 1
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 description 1
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- Furnace Housings, Linings, Walls, And Ceilings (AREA)
Abstract
The invention discloses a method for preparing a Sialon material inside a blast furnace. The method comprises the following steps: when performing fireproofing material machining inside the blast furnace, pre-burying a fire waste tube inside a construction body, wherein a fire waste tube inlet and a fire waste tube outlet are formed in a furnace wall; when the blast furnace is used, burning the fire waste tube to form a channel, introducing nitrogen into the channel, sealing up the channel outlet when the amounts at the inlet and outlet of the channel are identical, stopping introducing the nitrogen, pressing a filling material into the channel and pressing tightly, and subsequently normally operating the blast furnace. When the Sialon material is prepared inside the blast furnace by using the method, the method is simple and reasonable, and application and preparation of Sialon are integrated, so that the production cost is greatly saved, and redundant nitrogen of steel companies is sufficiently utilized. The method is applicable to large and small blast furnaces, the service life of the blast furnace is prolonged, and great economic and social benefits are brought to the companies.
Description
Technical field
The invention belongs to blast furnace ironmaking technical field of fire resistant material production, be specifically related to the preparation method of Sialon material in a kind of blast furnace.
Background technology
Before 30 years, blast furnace ironmaking refractory materials mainly uses clay brick and high alumina brick, the refractoriness of these bricks is generally about 1700 DEG C, and the actual temperature of blast-furnace bosh is higher than the refractoriness of refractory brick, cause the refractory materials in furnace high-temperature region short for duration of service, affect the work-ing life of blast furnace, China's intermediate repair life-span is 3-4, and between this 3-4, molten refractory materials and blast furnace slag cooled and solidified are supported blast furnace ironmaking by the main outer cooled wall that relies on furnace wall.
Along with the maximization of blast furnace, the improving constantly of combustion intensity and wind-warm syndrome, there is Si in Japan
3n
4in conjunction with SiC brick, make the furnace life of blast furnace reach 15 years.People found at Si in ceramic research afterwards
3n
4with Al
2o
3hot pressing has the Al of 60-70% in burning till
2o
3admittedly Si can be fused to
3n
4(i.e. Si in lattice
3n
4can the Al of solid solution 60-70% in lattice
2o
3) form a kind of sosoloid containing Si, Al, O, N, be abbreviated as " Sialon ", because of Si
3n
4be divided into α, β type, the product of the formation of β type is β-Sialon or β `-Sialon, and its chemical general formula is: Si
6-Zal
zo
zn
8-Z, Z represents the number of Siliciumatom and the nitrogen-atoms be substituted in silicon nitride, and research finds that Sialon properties is extremely superior further, develops the corundum brick of Sialon combination and the Al of Sialon combination
2o
3-SiC goods, and use on existing more than 20 the super-huge blast furnaces in the whole world, service life design 20 years.
After 20 years, it is believed that and use Sialon in conjunction with Al
2o
3blast-furnace production campaign can be brought up to more than 25 years by-SiC or Sialon corundum brick, the refractory materials researchist of China have also been made extensive work, Hong Yanruo, Sun Jialin etc. of University of Science & Technology, Beijing are assembled into " non-oxidized substance composite refractory " book the achievement in research of Sialon material, people have been had Sialon and Sialon composite refractory and is generally familiar with.China has at least ten universities to do the high temperature test of this kind of material in the past 25 years, delivered a lot of article, the sufficient proof superiority of Sialon material.But Sialon is in conjunction with Al
2o
3-SiC refractory material must be burnt till in nitrogen atmosphere, and cost is higher, and disposable input is comparatively large, and a lot of iron and steel enterprise is unwilling to drop into higher cost to utilize the good material of this superiority.
Summary of the invention
The object of the present invention is to provide the preparation method of Sialon material in a kind of easy to operate, blast furnace that cost is low.
For achieving the above object, the present invention adopts following technical scheme:
A preparation method for Sialon material in blast furnace, comprises the following steps:
(1) when in blast furnace, refractory materials is constructed (adopting Al2O3-SiC matter mould material or the spray material of a kind of containing metal aluminium and Pure Silicon Metal or the two alloy), pre-buried easy scaling loss tubing in construction body, easy scaling loss tubing is fixed on blast furnace inwall or refractory brick by support, and blast furnace wall is provided with import and the outlet of tubing;
(2) in blast furnace uses, easy scaling loss tubing burns formation passage, in passage, pass into nitrogen, forms Sialon being greater than at the temperature of 1400 DEG C, continues to pass into nitrogen 7-15 days, the closed channel outlet when the import and export nitrogen flow of passage is identical;
(3) logical nitrogen within maintaining nitrogen purge 8-10 hour, is stopped, press-in material compacting is entered to in-passage pressure, concrete operations are: from the compacting of passage end press-in press-in material, continue to pass into nitrogen 2-8 hour, then from the other end press-in press-in material compacting of passage, then increase nitrogen pressure and continue logical nitrogen 5-10 hour, make press-in material also form Sialon, blast furnace can normally run (continue baker or enter the ironmaking stage).
The pressure passing into nitrogen in step (2) is 0.01-0.02Mpa, and preferably, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, and described Oxygen in Nitrogen dividing potential drop is more low better, and described easy scaling loss tubing is vinyon tubing.Nitrogen pressure after increasing in step (3) is 0.05-0.1MPa.
In the arranging of easy scaling loss tubing, the setting of pipeline is wanted evenly, and the length thickness of pipe is moderate, and without cross-distribution situation, this is in order to when preventing nitrogen short circuit and press-in press-in material, material short circuit causes body inside of constructing to there is hole, affects the work-ing life of blast furnace.
Bottom blast furnace hearth, easy scaling loss tubing be arranged in parallel, distance bottom described easy scaling loss tubing and cupola well is that the furnace bottom of 1/4-1/3 is constructed body thickness (i.e. ceramic cup base thickness degree), adjacent tubes is apart from the 1/3-1/2 for furnace bottom construction body thickness, easy scaling loss tubing enters from the one end bottom blast furnace hearth, and the other end arranges outlet.
Blast-furnace bosh and bosh gas index position easy scaling loss tubing spiral is arranged, the distance of described easy scaling loss tubing and furnace wall is the construction body construction thickness of 1/3-1/2, adjacent tubes apart from (pitch) be construction body thickness 1/2-2/3, import and outlet along tubing tangential direction extraction stove outside and be connected with nitrogenous source.
Preferably, when cupola well (ceramic wall of cup) is constructed, easy scaling loss tubing spiral is arranged, the body thickness < 350mm if cupola well (ceramic wall of cup) is constructed, the distance of easy scaling loss tubing and cupola well outer wall is 2/5 construction body thickness, and adjacent tubes distance is 1/2 construction body thickness; The body thickness > 350mm if cupola well (ceramic wall of cup) is constructed, easy scaling loss tubing parallel double spiral is arranged, the pipe distance of parallel double tube is 1/2 construction body thickness, interior pipe distance cupola well (ceramic wall of cup) inwall is 1/4 construction body thickness, outer tube distance cupola well (ceramic wall of cup) outer wall is 1/4 construction body thickness, and pitch is 1/2 construction body thickness; Easy scaling loss tubing is wanted moderate and is constructed body inside turn after one week or two weeks along tangential direction extraction cupola well (ceramic wall of cup) of tubing outward at cupola well (ceramic wall of cup).
The two ends of the easy scaling loss tubing of every root are provided with heat resisting pipe joint, melt to prevent steel pipe and construction weight is worked the mischief, the length that one end of heat resisting pipe joint enters construction body inside is 50-100mm, and it is outer and be connected with nitrogenous source that the other end of heat resisting pipe joint draws stove through furnace wall fire brick layer.
In the use of blast furnace, if easily the burning of scaling loss tubing not to the utmost, first should blow out residue with high pressure gas, then pass into nitrogen and react.
The material comprising following weight part of construction material used: Al in present method
2o
3material 50-60 part, SiC 10-30 part, silicon aluminium alloy powder 8-12 part, C powder 0-3 part, rare earth oxide 0-2 part, clay 0-5 part.In wherein said silicon aluminium alloy powder, the mass ratio of Al and Si is 1: (3-4), and specifically needs according to casting and constructing the water adding 4-5 part.
Press-in material used comprises the material of following weight part: Al
2o
3material 50-60 part, SiC 10-30 part, silicon aluminium alloy powder 8-12 part, C powder 0-3 part, rare earth oxide 0-2 part, clay 0-5 part, in wherein said silicon aluminium alloy powder, the mass ratio of Al and Si is 1: (3-4); Granularity≤the 3mm of described press-in material.
Preferably, described rare earth oxide is oxide compound or its mixed oxide of Y2O3 or La, Ce, Pr, Nd, Pm, Sm, Eu, Gd etc., and described rare earth oxide is from hamartite or xenotime; Construction is expected and Al described in press-in material
2o
3low-carbon (LC) Brown Alundum mass percent>=90% in material, all the other trace of Al
2o
3material is white fused alumina micro mist or α-Al
2o
3super-fine powder; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.8%, TiO
2mass percentage is 1-3%; Fe in low-carbon (LC) Brown Alundum
2o
3and TiO
2existence just in time as catalyzer, promote the formation of Sialon material.
Preferably, the amount of selecting of alloy powder is the Sialon in order to ensure forming 25-33% in matrix, and the Z value in Sialon is comparatively suitable at 1.5-2.5.
The present invention prepares Sialon material in blast furnace, method advantages of simple, without the need to building complicated nitriding furnace and empty point workshop, the use of Sialon is integrated with preparation, has greatly saved production cost, and has taken full advantage of the unnecessary emptying nitrogen of iron and steel enterprise.Present method is suitable for large small furnace, is especially applicable to the repairing to key position in the current intensification of smelting process in BF of China, can extends blast furnace campaign, bring great economic benefit and social benefit to enterprise.
Accompanying drawing explanation
Fig. 1 is blast-furnace bosh position constructing structure schematic diagram;
Fig. 2 is blast furnace hearth position constructing structure schematic diagram.
Embodiment
Below in conjunction with embodiment, the present invention will be further explained illustrates, but protection scope of the present invention is not limited to this.
embodiment 1
The present embodiment construction body construction material used is made up of the material of following weight part: Al
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 90% to material 50 parts, and all the other are α-Al
2o
3super-fine powder; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.6%, TiO
2mass percentage is 1-3%), SiC10 part, silicon aluminium alloy powder 8 parts (mass ratio of Al: Si is 1: 3), 2 parts, C powder, 5 parts, water;
Press-in material used is made up of the material of following weight part: Al
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 90% to material 50 parts, and all the other are α-Al
2o
3super-fine powder; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.6%, TiO
2mass percentage is 1-3%), SiC10 part, silicon aluminium alloy powder 8 parts (mass ratio of Al and Si is 1: 3.5), 2 parts, C powder, rare earth oxide (from xenotime) 0.1 part, clay 1 part, 3 parts, water, press-in material granularity≤3mm.
(1) as shown in Figure 1 when the bosh 2 position refractory materials construction of blast furnace 1, pre-buried vinyon tubing 4 in construction body 3, vinyon tubing 4 is fixed on fire brick layer 5 by support, the construction body 3 that described vinyon tubing 4 and the distance of furnace wall are 1/3 is constructed thickness, and furnace wall is provided with import and the outlet of tubing.Tubing spiral is arranged, and pipe is apart from being 1/2 of construction body thickness up and down, and import and outlet are drawn outside stove along the tangential direction of tubing.The two ends of every root vinyon tubing 4 are provided with heat resisting pipe joint, and melt to prevent steel pipe and work the mischief to construction weight, the length that heat resisting pipe joint enters construction body inside is 50mm.Wherein, the caliber of described every root vinyon tubing is 37mm, and length is that 12m(was along stove inside turn one week).
(2) in the process of blast oven, pre-buried vinyon tubing is burnt completely, passage is formed in construction body, first blow out residue with high pressure gas, then pass into nitrogen in passage, continue to pass into nitrogen 7 days, Sialon. closed channel outlet when the import and export flow of channel of nitrogen is identical is formed gradually under the high temperature of > 1400 DEG C, maintaining nitrogen purge 8 hours, allows nitrogen permeate to depths at a distance, is beneficial to the abundant formation of construction body Sialon; Described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, and the pressure passing into nitrogen is 0.01Mpa.
(3) logical nitrogen is stopped, press-in material compacting is entered to in-passage pressure, concrete operations are: from the compacting of channel entrance press-in press-in material, continue to pass into nitrogen 2 hours, then from the outlet press-in press-in material compacting of passage, then increase nitrogen pressure and continue logical nitrogen 5 hours, blast furnace can normally run, can continue baker or enter the ironmaking stage, the nitrogen pressure after wherein increasing is 0.05MPa.
Cannot sample detecting after this method synthesis Sialon pour mass.Available construction materials break into standard test block the middle 1300-1400 DEG C of insulation of nitrogenize reheating stove (in nitrogen atmosphere) 8 hours, 1500 DEG C of insulations are burnt till for 8 hours, indices is detected, the Z value of gained Sialon material is 1.5-2.5, compressive strength>=150Mpa, folding strength>=35Mpa, thermal expansivity is 2-3 × 10
-6/ K, meets the standard of Sialon material, can as reference foundation.
embodiment 2
The present embodiment construction body construction material used forms Al by the material of following weight part
2o
3(wherein low-carbon (LC) Brown Alundum quality accounts for Al to material 60 parts
2o
395% of material, all the other are α-Al
2o
3super-fine powder; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.6%, TiO
2mass percentage is 1-3%), SiC30 part, silicon aluminium alloy powder 12 parts (mass ratio of Al: Si is 1: 4), 3 parts, C powder, rare earth oxide (from xenotime) 2 parts, clay 5 parts, 4 parts, water.
Press-in material used forms Al by the material of following weight part
2o
3(wherein low-carbon (LC) Brown Alundum quality accounts for Al to material 60 parts
2o
395% of material, all the other are α-Al
2o
3super-fine powder; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.6%, TiO
2mass percentage is 1-3%), SiC30 part, silicon aluminium alloy powder 12 parts (mass ratio of Al and Si is 1: 4), 3 parts, C powder, rare earth oxide (from xenotime) 2 parts, clay 5 parts, press-in material granularity≤3mm.
(1) as shown in Figure 2 when the cupola well 5 position refractory materials construction of blast furnace 1, pre-buried PVC 7 in construction body 6, PVC 7 bottom cupola well be arranged in parallel and to be fixed on bottom blast furnace on carbon brick 8 by support, PVC 7 is 1/4 construction body thickness with the distance bottom cupola well, and furnace wall is provided with import and the outlet of tubing.
On bosh gas index, PVC 7 spiral arranges and is fixed on bosh gas index refractory brick, and described PVC 7 and the distance of furnace wall are the construction body construction thickness of 2/5, and furnace wall is provided with import and the outlet of tubing.Pipe is apart from being 2/3 of construction body thickness up and down, and import and outlet are drawn outside stove along the tangential direction of tubing.
The two ends of every root PVC 7 are provided with heat resisting pipe joint, melt to prevent steel pipe and construction weight is worked the mischief, the length that heat resisting pipe joint enters construction body inside is 100mm, coupling connects wherein through furnace wall refractory brickwork pass-out stove is outer with nitrogenous source, the caliber of described PVC 7 is 51mm, cupola well bottom lengths is 5.5m, and bosh gas index length is 17.2m(around cupola well one week).
(2) in the process of blast oven, pre-buried PVC is burnt completely, forms passage, first blow out residue with high pressure gas in construction body, nitrogen is passed into again in passage, continue to pass into nitrogen 15 days, the closed channel outlet when the import and export flow of channel of nitrogen is identical, maintaining nitrogen purge 10 hours, nitrogen is allowed to permeate to depths at a distance, be beneficial to the abundant formation of construction body Sialon, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, and the pressure passing into nitrogen is 0.02Mpa.
(3) logical nitrogen is stopped, press-in material compacting is entered to in-passage pressure, concrete operations are: from the compacting of channel entrance press-in press-in material, continue to pass into nitrogen 6 hours, then from the outlet press-in press-in material compacting of passage, then increase nitrogen pressure and continue logical nitrogen 10 hours, blast furnace can normally run, can continue baker or enter the ironmaking stage, the nitrogen pressure after wherein increasing is 0.1MPa.
Cannot sample detecting after this method synthesis Sialon pour mass.Available construction materials break into standard test block the middle 1300-1400 DEG C of insulation of nitrogenize reheating stove (in nitrogen atmosphere) 8 hours, 1500 DEG C of insulations are burnt till for 8 hours, indices is detected, the Z value of gained Sialon material is 1.5-2.5, compressive strength>=150Mpa, folding strength>=35Mpa, thermal expansivity is 2-3 × 10
-6/ K, meets the standard of Sialon material, can as reference foundation.
embodiment 3
The present embodiment construction body construction material used forms Al by the material of following weight part
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 93% to material 55 parts, and all the other are white fused alumina micro mist; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.7%, TiO
2mass percentage is 1-3%), SiC20 part, silicon aluminium alloy powder 10 parts (mass ratio of Al: Si is 1: 3.5), rare earth oxide (from hamartite) 1 part, 5 parts, water.
Press-in material used forms Al by the material of following weight part
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 93% to material 55 parts, and all the other are white fused alumina micro mist, Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.4-0.7%, TiO
2mass percentage is 1-3%), SiC20 part, silicon aluminium alloy powder 10 parts (mass ratio of Al: Si is 1: 3.8), press-in material granularity≤3mm.
(1) when the bosh position refractory materials construction of blast furnace, pre-buried chlorinatedpolyethylene tubing in construction body, chlorinatedpolyethylene tubing is fixed on fire brick layer by support, the distance of described chlorinatedpolyethylene tubing and furnace wall is the construction body construction thickness of 11/30, and furnace wall is provided with import and the outlet of tubing.Tubing spiral is arranged, and pipe is apart from being 7/12 of construction thickness up and down, and import and outlet are drawn outside stove along the tangential direction of tubing.The two ends of every root chlorinatedpolyethylene tubing are provided with heat resisting pipe joint, and melt to prevent steel pipe and work the mischief to construction weight, the length that heat resisting pipe joint enters construction body inside is 100mm.Wherein, the caliber of described every root chlorinatedpolyethylene tubing is 18mm, and length is 25m(around bosh one week).
(2) in the process of blast oven, the pre-buried complete imitation frosted glass of chlorinatedpolyethylene tubing, form passage in construction body, first blow out residue with high pressure gas, then pass into nitrogen in passage, continue to pass into nitrogen 10 days, the closed channel outlet when the import and export flow of channel of nitrogen is identical, maintaining nitrogen purge 9 hours, allows nitrogen permeate to depths at a distance, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, and the pressure passing into nitrogen is 0.015Mpa.
(3) logical nitrogen is stopped, press-in material compacting is entered to in-passage pressure, concrete operations are: from the compacting of channel entrance press-in press-in material, continue to pass into nitrogen 5.5 hours, then from the outlet press-in press-in material compacting of passage, then increase nitrogen pressure and continue logical nitrogen 8 hours, blast furnace can normally run, can continue baker or enter the ironmaking stage, the nitrogen pressure after wherein increasing is 0.07MPa.
Cannot sample detecting after this method synthesis Sialon pour mass.Available construction materials break into standard test block the middle 1300-1400 DEG C of insulation of nitrogenize reheating stove (in nitrogen atmosphere) 8 hours, 1500 DEG C of insulations are burnt till for 8 hours, indices is detected, the Z value of gained Sialon material is 1.5-2.5, compressive strength>=150Mpa, folding strength>=35Mpa, thermal expansivity is 2-3 × 10
-6/ K, meets the standard of Sialon material, can as reference foundation.
embodiment 4
The present embodiment construction body construction material used forms Al by the material of following weight part
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 92% to material 58 parts, and white fused alumina micro mist mass percent is 5%, α-Al
2o
3super-fine powder mass percent is 3%; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.5-0.8%, TiO
2mass percentage is 1-3%), SiC25 part, silicon aluminium alloy powder 9 parts (mass ratio of Al: Si is 1: 3.6), 2.8 parts, C powder, rare earth oxide (from xenotime) 1.5 parts, clay 4 parts, 4 parts, water.
Press-in material used forms Al by the material of following weight part
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 92% to material 58 parts, and white fused alumina micro mist mass percent is 5%, α-Al
2o
3super-fine powder mass percent is 3%; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.5-0.8%, TiO
2mass percentage is 1-3%), SiC25 part, silicon aluminium alloy powder 9 parts (mass ratio of Al: Si is 1: 3.6), 2.8 parts, C powder, rare earth (from xenotime) 2 parts, clay 3 parts, press-in material granularity≤3mm.
(1) when the bosh position refractory materials construction of blast furnace, pre-buried polybutene tubing in construction body, polybutene tubing is fixed on blast furnace inwall by support, and the distance of described polybutene tubing and furnace wall is the construction body construction thickness of 11/30, and furnace wall is provided with import and the outlet of tubing.Tubing spiral is arranged, and pipe is apart from being 7/12 of construction thickness up and down, and import and outlet are drawn outside stove along the tangential direction of tubing.The two ends of every root polybutene tubing are provided with heat resisting pipe joint, and melt to prevent steel pipe and work the mischief to construction weight, the length that heat resisting pipe joint enters construction body inside is 80mm, and heat resisting pipe joint connects nitrogenous source outward through furnace wall fire brick layer pass-out stove.Wherein, the caliber of described every root polybutene tubing is 50mm, and length is 3/4 of 12m(bosh partial circumference).
(2) in the process of blast oven, pre-buried polybutene tubing is burnt completely, form passage in construction body, first blow out residue with high pressure gas, then pass into nitrogen in passage, continue to pass into nitrogen 12 days, the closed channel outlet when the import and export flow of channel of nitrogen is identical, maintaining nitrogen purge 9.5 hours, allows nitrogen permeate to depths at a distance, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, and the pressure passing into nitrogen is 0.018Mpa.
(3) logical nitrogen is stopped, press-in material compacting is entered to in-passage pressure, concrete operations are: from the compacting of channel entrance press-in press-in material, continue to pass into nitrogen 7 hours, then from the outlet press-in press-in material compacting of passage, then increase nitrogen pressure and continue logical nitrogen 9 hours, blast furnace can normally run, can continue baker or enter the ironmaking stage, the nitrogen pressure after wherein increasing is 0.1MPa.
Cannot sample detecting after this method synthesis Sialon pour mass.Available construction materials break into standard test block the middle 1300-1400 DEG C of insulation of nitrogenize reheating stove (in nitrogen atmosphere) 8 hours, 1500 DEG C of insulations are burnt till for 8 hours, indices is detected, the Z value of gained Sialon material is 1.5-2.5, compressive strength>=150Mpa, folding strength>=35Mpa, thermal expansivity is 2-3 × 10
-6/ K, meets the standard of Sialon material, can as reference foundation.
embodiment 5
When blast furnace spraying application, spray material by following weight part material form: Al
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 93% to material 60 parts, and all the other are white fused alumina micro mist; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.6-0.8%, TiO
2mass percentage is 1-3%), SiC30 part, silicon aluminium alloy powder 10 parts (mass ratio of Al and Si is 1: 3.8), 2.8 parts, C powder, fireclay 3 parts, 5 parts, water.
Press-in material by following weight part material form: Al
2o
3(wherein low-carbon (LC) Brown Alundum mass percent is 93% to material 60 parts, and all the other are white fused alumina micro mist; Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.6-0.8%, TiO
2mass percentage is 1-3%), SiC30 part, silicon aluminium alloy powder 10 parts (mass ratio of Al and Si is 1: 3.8), 2.8 parts, C powder, rare earth oxide (from hamartite) 1.5 parts, clay 1 part; Press-in material granularity≤1mm.
The bottom of the bosh of blast furnace, furnace bosh and shaft is repaired at blast furnace production process, vexed good stove fire after blast furnace staying, guarantee to enter without after coal gas, expansion bolt is installed in furnace wall and fixes vinyon tubing (every root length is 25m), vinyon tubing spiral is arranged, and diameter is 15mm; Polyvinyl piping materials distance furnace wall 70mm, the import of polyvinyl piping materials and outlet are drawn outside stove along the tangential direction of tubing.The two ends of every root polybutene tubing are provided with heat resisting pipe joint, can carry out spraying application after the fixation of stove interior conduit, coating thickness for pipeline spray put down after spray 130mm again, total coating thickness is 200mm.
After sprayed coating solidifies blast furnace gradually again wind resume production, passage is formed after polyethylene pipe scaling loss, nitrogen is passed in passage, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, nitrogen pressure is 0.01MPa, logical nitrogen stopped after 7 days, press-in material compacting is entered to in-passage pressure, concrete operations are: from the compacting of channel entrance press-in press-in material, continue to pass into nitrogen 7 hours, nitrogen is allowed to permeate to depths at a distance, then from the outlet press-in press-in material compacting of passage, then increase nitrogen pressure and continue logical nitrogen 9 hours, blast furnace can carry out normal production operation, nitrogen pressure after wherein increasing is 0.1MPa.
Cannot sample detecting after this method synthesis Sialon construction body.Available construction materials break into standard test block the middle 1300-1400 DEG C of insulation of nitrogenize reheating stove (in nitrogen atmosphere) 8 hours, 1500 DEG C of insulations are burnt till for 8 hours, indices is detected, the Z value of gained Sialon material is 1.5-2.5, compressive strength>=150Mpa, folding strength>=35Mpa, thermal expansivity is 2-3 × 10
-6/ K, meets the standard of Sialon material, can as reference foundation.
embodiment 6
When blast furnace spraying application, spray material by following weight part material form: low-carbon (LC) Brown Alundum 60 parts, (Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.6-0.8%, TiO
2mass percentage is 1-3%), SiC30 part, silicon aluminium alloy powder 8 parts (mass ratio of Al and Si is 1: 3), 2.8 parts, C powder, fireclay 3 parts, liquid binder 8-10 part.
Press-in material by following weight part material form: low-carbon (LC) Brown Alundum 60 parts, (Fe in low-carbon (LC) Brown Alundum
2o
3mass percentage is 0.6-0.8%, TiO
2mass percentage is 1-3%), SiC30 part, silicon aluminium alloy powder 8 parts (mass ratio of Al and Si is 1: 3), 2.8 parts, C powder, rare earth (from xenotime) 1.5 parts, clay 1 part; Press-in material granularity≤1mm.
The bosh of blast furnace is repaired at blast furnace production process, the bottom of furnace bosh and shaft, vexed good stove fire after blast furnace staying, guarantee without the laggard people of coal gas, be lining with in furnace wall and beat expansion screw installation V-type anchoring piece (spraying place 9/m2), then on anchoring piece, distance always serves as a contrast 70mm place and hangs heat-resisting steel mesh, then a φ 15mm is used, the polyethylene tube of 30 meters long spirals at stove internal screw, and to be fixed on high temperature steel online, pitch is 150mm, the stainless steel heat-resistant joint of polyethylene tube only stays 60mm in stove, connect with nitrogenous source after pass-out stove is outer, spraying application is started after the steel mesh at spraying position and combustible tube are completely fixed, 130mm is sprayed again thick after combustible tube is buried, 220mm.
After sprayed coating solidifies blast furnace gradually again wind resume production, passage is formed after polyethylene pipe scaling loss, in passage, pass into nitrogen, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation, and nitrogen pressure increases to 0.01MPa in proper order, logical nitrogen stopped after 7 days, enter press-in material compacting to in-passage pressure, concrete operations are: from channel entrance press-in press-in material, if press-in material can from outlet out, then close outlet, continue to pass into nitrogen after compacting and within 12 hours, complete manufacturing of Sialon construction body.Blast furnace can carry out normal production operation, and the nitrogen pressure after wherein increasing is 0.15MPa.
The reason spraying only elongated with one path combustible tube is that later stage press-in material compacting is pressed unreal or is pressed into, and all can not have much impacts to construction body life time.
Still cannot sample detecting after this method synthesis Sialon construction body.Available construction materials break into standard test block the middle 1300-1400 DEG C of insulation of nitrogenize reheating stove (in nitrogen atmosphere) 8 hours, 1500 DEG C of insulations are burnt till for 8 hours, indices is detected, the Z value of gained Sialon material is 1.5-2.5, compressive strength>=150Mpa, folding strength>=35Mpa, thermal expansivity is 2-3 × 10
-6/ K, meets the standard of Sialon material, can as reference foundation.
Claims (8)
1. the preparation method of Sialon material in blast furnace, is characterized in that, comprise the following steps:
(1) in blast furnace, when refractory materials construction, the construction material of the Al2O3-SiC matter of a kind of containing metal Al, Si or the two alloy is adopted, during construction, pre-buried easy scaling loss tubing in construction body, blast furnace wall is provided with import and the outlet of easy scaling loss tubing;
(2) in blast furnace uses, easy scaling loss tubing burns formation passage, in passage, pass into nitrogen, the closed channel outlet when the import and export nitrogen flow of passage is identical;
(3) within maintaining nitrogen purge 8-10 hour, stop, entering press-in material compacting to in-passage pressure, blast furnace can normally run; Described press-in material comprises the material of following weight part: Al
2o
3material 50-60 part, SiC 10-30 part, silicon aluminium alloy powder 8-12 part, C powder 0-3 part, rare earth oxide 0-2 part, clay 0-5 part, in wherein said silicon aluminium alloy powder, the mass ratio of Al and Si is 1: (3-4).
2. the preparation method of Sialon material in a kind of blast furnace as claimed in claim 1, it is characterized in that, bottom blast furnace hearth, easy scaling loss tubing be arranged in parallel, distance bottom described easy scaling loss tubing and cupola well is that the furnace bottom of 1/4-1/3 is constructed body thickness, and adjacent tubes is apart from the 1/3-1/2 of body thickness of constructing for furnace bottom.
3. the preparation method of Sialon material in a kind of blast furnace as claimed in claim 1, it is characterized in that, the easy scaling loss tubing spiral of blast-furnace bosh and bosh gas index position is arranged, the distance of described easy scaling loss tubing and furnace wall is the construction body construction thickness of 1/3-1/2, adjacent tubes is apart from the 1/2-2/3 for construction body thickness, and import and outlet are drawn outside stove along the tangential direction of tubing.
4. the preparation method of Sialon material in blast furnace as described in as arbitrary in claim 1-3, it is characterized in that, the two ends of the easy scaling loss tubing of every root are provided with heat resisting pipe joint, and the length that heat resisting pipe joint enters construction body inside is 50-100mm.
5. the preparation method of Sialon material in a kind of blast furnace as claimed in claim 1, it is characterized in that, described construction body construction material used comprises the material of following weight part: Al
2o
3material 50-60 part, SiC 10-30 part, silicon aluminium alloy powder 8-12 part, C powder 0-3 part, rare earth oxide 0-2 part, clay 0-5 part, in wherein said silicon aluminium alloy powder, the mass ratio of Al and Si is 1: (3-4).
6. the preparation method of Sialon material in blast furnace as described in claim 1 or 5, is characterized in that, described Al
2o
3low-carbon (LC) Brown Alundum mass percent>=90% in material; Fe in low-carbon (LC) Brown Alundum
2o
3for 0.4-0.8wt%, TiO
2for 1-3wt%.
7. the preparation method of Sialon material in a kind of blast furnace as claimed in claim 1, it is characterized in that, the pressure passing into nitrogen in step (2) is 0.01-0.02MPa.
8. the preparation method of Sialon material in a kind of blast furnace as claimed in claim 1, it is characterized in that, described nitrogen is the nitrogen more than needed produced in steel-making oxygen preparation; Described easy scaling loss tubing is vinyon tubing.
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| CN201310509414.2A CN103553669B (en) | 2013-10-25 | 2013-10-25 | Method for preparing Sialon material inside blast furnace |
| PCT/CN2014/089507 WO2015058723A1 (en) | 2013-10-25 | 2014-10-24 | Preparation method of blast furnace or iron runner sialon lining |
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| CN201310509414.2A CN103553669B (en) | 2013-10-25 | 2013-10-25 | Method for preparing Sialon material inside blast furnace |
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| CN108178634B (en) * | 2018-02-08 | 2021-02-12 | 陕西科谷新材料科技有限公司 | Preparation method of sialon combined silicon carbide ceramic |
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| CN1300057C (en) * | 2004-08-25 | 2007-02-14 | 武汉科技大学 | Refractory Sialon corundum brick material for blast flurnace and its prepn process |
| CN1326801C (en) * | 2005-03-29 | 2007-07-18 | 郑州大学 | Method for preparing composite material combined with corundum based on bauxite beta-Sialon |
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