내화물의 일반적인특성 포스렉 R&D CENTER 1
- Content - 1. 내화물의종류 2. 내화물제조공정도 3. 각설비별내화물적용사례 2
1. 내화물의분류 1-1. 화학성질상분류 [ 산성내화물 : R(R:Metal ion) O 2 ex: SiO 2 ] [ 중성내화물 : R 2 O 3 ex: Al 2 O 3 ] [ 염기성내화물 :RO ex :MgO 등과같은화학성분을주성분으로하는내화물 ] 3
1-2. 2. Ternary System 의한분류 4
2. 내화물제조공정도 2-1. 내화물원료종류및준비과정 산성내화물 중성내화물 채광 열처리 분쇄 채광 열처리 분쇄 ( 저급 ) 채광 Bayer Process 소성 분쇄 ( 고급 ) Sea water Sintered Magnesia Clinker : CaCO 염기성내화물 3 CaO Ca(OH) 2 Mg(OH) 2 MgO Natured Magnesia Clinker: MgCO 3 MgO Fused Magnesia Clinker: MgO Fusing(3000 <) 해수MgO제조공정도 Table MgO Clinker 의특성 MgO(%) Bulk Density Porosity(%) Sintered MgO 95~99 3.30~3.45 1.0~3.0 Natured MgO 80~97 3.10~3.25 4.0~12.0 Fused MgO 96~99 3.40~3.47 1.0~2.0 5
2-2. 2. 제조방법에따른원료품질특성 (MgO Clinker) Grain boundary Pore Periclase Natured MgO Sintered MgO Fused MgO S-MgO종류 Crystal Size ( μm ) Natured MgO 60~90 Sintered MgO 40~70 Fused MgO 500< 6
2-3. 내화물제품제조공정도 2-3-1. 불소성내화물 제조공정도 적용제품 Al2O3-Carbon, Al2O3-SiC-Carbon, Al2O3-MgO-Carbon Al2O3-ZrO2-Carbon, Al2O3-Cr2O3-SiC-MgO-Carbon MgO-Carbon, MgO-Al2O3-Carbon, MgO-CaO-Carbon ZrO2-Carbon 적용설비 혼선차 (Topedo car), 전로, Ladle, 전기로, Sliding Gate, Nozzle 7
2-3-2. 2. 소성내화물 제조공정도 적용제품 점토질벽돌 (High SiO2), 알루미나질벽돌 (Al2O3-SiO2), 고알루미나 벽돌, 단열형벽돌, MgO 벽돌, MgO-Cr2O3 질벽돌, MgO-CaO 질벽돌 적용설비 열풍로, 고로, 혼선차, 전로,R.H, Ladle 영구장, 연주등모든설비에사용 8
2-3-3. 3. 부정형내화물 제조공정도 제품종류 Ramming 재, Plastic 재, Coating 재, Spray 재, Castable,Stamp 재 Mortar 재, Flame Gunning 재 적용설비 열풍로, 고로, 혼선차, 전로,R.H, Ladle 영구장, 연주등모든설비에사용 9
3. 각설비별내화물적용사례 3-1. 제철및제강조업 Flow 일괄제철소조업 Flow 제강조업 Flow 10
3-2. 각설비별내화물구성형태 고로 11
전기로 혼선차 12
전로 13
염기성내화물의사용원료특성 Sintered MgO Cl Fused MgO Cl 품질요구특성 High Purity, low B 2 O 3 Periclase의대형화 CaO/SiO 2 적정화 Crystal Size의최대화 입계용적의최소화 사용제품 MgO-C Brick Mg-Cr Brick MgO-Al 2 O 3 -C Brick MTA Brick Sinter,Fused Alumina High Density,Purity MgO-Al 2 O 3 -C Sintered Spinel Cl Fused Magchro Cl Chrome Ore MgO+Al 2 O 3 함량의최대화 Spinel Bonding 견고 입계용적의최소화 Crystal Size의최대화 Total Flux 함량의최소화 High Cr 2 O 3 화 Gangue Material의최소화 비표면적의최소화 Spinel Brick Spinel-C Brick Mg-Cr Brick Graphite High Purity, Flake 상 MgO-C Brick 14
MgO Clinker 의 B 2 O 3 와침식성 화학성분 (%) MgO B 2O 3 Bulk density (g/ cm3 ) Sinterd MgO F- MgO a b c d 98.5 0.07 98.0 0.04 99.2 0.001 98.5 0.18 3.40 3.42 3.44 3.38 Crystal size( μm ) 50 55 60 450 Corrosion index 120 100 80 60 40 20 MgOClinker B 2 O 3 함량 : Corrosion Resistance MgO Clinker 의 B 2 O 3 와 Hydration Test condition 3hrs at 0.3MPa steam pressure MgOClinker 의 B 2 O 3 : Hydration Resistance 저융점액상물질 B 2 O 3 -SiO 2 생성으로소화발생억제 Weight gain(%) 12 10 8 6 4 2 0 0 0 0.05 0.1 0.15 0.2 B 2O 3 content in M go clinker Magnesite Mgo Cl'(No boron) Sea water MgO Cl'(0.1% B2O3) Sea water MgO Cl'(0.15-0.4% B2O3) 90 92.5 95 97.5 100 MgO content(%) 15
Magnesia Brick 의미세구조및특성 - Microstructure Periclase pore 1.Chemical Reaction Resistance - MgO M.P:2800 2.Thermal Conductivity -2.5kcal/m hr (at 1000 ) 3.High Specific Heat - 0.27kcal/ (at 1000 ) 4.High thermal Shock Resistance - Directbond (High Burned) 5.High Thermal Expansion - 1.3% (at 1000 ) 6.Low Deformation in High Tem. -T 2 :1650 < 7.Very High Refractoriness 16
Magnesia Carbon,Magnesia Alumina Carbon Brick Material : Magnesia Clinker, Spinel,Alumina (Sintered,Fused) graphite, Metal Chemical Comp.(%) Al 2 O 3 F.Carbon Crystal Size Property S-Alumina F-Alumina 95~99 20~70 μm 50~200 μm Spinel Graphite 95~99% Nonwetting Metal Mg/Al, Al,Si,B 4 C,CaB 6,SiC etc Antioxidant 17
Magnesia Carbon Brick 의미세구조및특성 Flake graphite F-MgO 1.Unburned,Burned 2.High Corrosion Resistance -graphite:wetting Resistance[FeO] 3.High thermo-mechanically Shock Resistance -graphite:thin film(flake구조 ) 4.Very sensitive in Oxidation condition MgO-C Brick Graphite Metal -C+O 2 CO 2 5.High thermal Conductivity -graphite:400btu/hr.ft 2. /in at 1090 18
Magnesia Clinker 순도와침식성 Mixing ratio(wt%) Test brick(mgo-c) Magnesia 87 Graphite 13 Metal MgO Purity : Corrosion Resistance none Corrosion depth(mm 12 10 8 6 4 2 0 94 95 96 97 98 99 100 MgO Content(%) MgO Clinker 결정크기와침식성 M ix in g ratio(w t% ) Test brick(m go-c) M agnesia 82 Graphite 18 M e ta l Fused Magnesia clinker a b c d MgO (%) 99.0 97.4 97.1 97.0 Chemical B 2O 3(%) 0.01 tr tr tr composition CaO/SiO2 1.34 4.75 2.65 1.82 Crystal size( μm ) 1500 1000 700 500 + α Corrosion index 170 150 130 110 90 70 50 400 600 800 1000 1200 1400 1600 Crystal size( μm ) MgO Clinker Crystal size : Corrosion Resistance 19
결정질, 비결정질 graphite 와침식성 Test sample A B C D 200 14 Mixing ratio (wt%) Magnesia F.G A.C Metal F.C :Flake graphite 93 7 0 93 5 2 A.C :Amorporous graphite 93 3 4 93 1 6 Corrosion index 180 160 140 120 100 80 A B C D 12 10 8 6 4 2 耐 Spalling( 回數 ) 1400 H 2O 浸積 Sample Corrosion Resistance: Flake graphite > Amorporous graphite 20
MgO Clinker CaO/SiO 2 비와침식성 Corrosion index 160 150 140 130 120 110 100 90 80 1 1.5 2 2.5 3 3.5 4 4.5 CaO/SiO 2 ratio in MgO clinker MgO Clinker 의 Grain Boundary CaO/SiO 2 ratio : Corrosion Resistance ( CaO/SiO 2 :1.8~2.4) Fig. Relationship between corrosion resistance and CaO/SiO 2 ratio of Fused MgO in MgO-C brick 21
정련로 (R.H, VOD,AOD) R.H 22
Magnesia Chrome Brick(R.H 적용내화물 ) Material : Magnesia Clinker, Chrome Ore(Natured) Fused Mg-Cr Clinker [ MgO+Chrome:Fusing) Cr 2 O 3, Addertive Table. Chrome material 의특성 Chemical Comp.(%) Physical MgO Cr 2 O 3 T-Flux B.D Chrome Ore 10~20 30~58 28~47 3.70~3.85 Fused Mg-Cr 55~63 19~35 10~20 3.78~3.90 Cr 2 O 3-99< - - 23
Chrome material 과 Mg-Cr Brick 의미세구조 Cr Ore MgO Cl Chrome Ore DB Brick Fused Mg-Cr Cr Ore Fused Mg-Cr SRB Brick 24
Dolomite Brick( 정련로적용내화물 ) Material : Magnesia Clinker, Dolomite Clinker Dolomite Clinker 종류및제조방법 1. Natured Dolomite Clinker : Mg CaCO 3 MgO CaO (shaft kiln,r/k) 2. Sea Water Dolomite Clinker : CaCO 3 CaO Ca(OH) 2 Mg(OH) 2 --------- 1 CaCO 3 CaO Ca(OH) 2 Mg(OH) 2 + Ca(OH) 2 MgO CaO Table.Dolomite Clinker 의종류 --------- 2 -------- 1+2 Chemical comp.(%) Physical MgO CaO B.D Dolomite Clinker 45~50 50~55 3.10~3.17 Mag-Dolomite Clinker 70~75 25~30 3.20~3.25 25
Dolomite Brick 의미세구조및특성 Dolomite Clinker Dolomite Cl MgO 1.Burned,Unburned 2.High Refining effect in Steel 3.Very High Thermal Shock Resistance [Dolomite Brick>Mg-Cr Brick] 4.Low Deformation in High Temp. 5.Very Sensitive in Hydroreaction 6.High Refractoriness 7.High Chemical Resistance in High basicity slag -CaO/SiO 2 :1.0< Dolomite Brick 26
Spinel Brick(Cr-Free 내화물 ) Material : Magnesia Clinker, Spinel Clinker 합성 Spinel Clinker 종류및제조방법 1. Synthetic Spinel Clinker : MgO + Al 2 O 3 MgO Al 2 O 3 Sintered:R/K, Fused:Electric Furnace Table. Spinel Clinker 의특성 Chemical comp.(%) Physical Property MgO Al 2 O 3 B.D Crystal size 30 70 3.25 S-Spinel 50 50 3.40 F-Spinel 50 50 3.48 5~20 μm 27
Spinel Brick 의미세구조및특성 Free MgO Spinel 1.High Chemical Reaction Resistance -MgO Al 2 O 3 (M.P:2130 ) -MgO+Al 2 O 3 :98%< 2.High Thermal Shock Resistance 3.High Penetration Resistance -Na,K,Cl 4.High gas attack Resistance MgO Spinel - Acid gas:co 2,SO 2 5.Low Thermal Expansion - 1.0% at 1000 6.High Stability Structure -Spinelbonding 7.Low Permeability - 1500 centidarcy 28
래들및연주기 29