Development of Ironmaking Technology Abstract The Japanese steel industry has a long history of introducing new and innovative technologies in the field of ironmaking. The new technologies introduced during the past ten years include technologies to use cheaper and lowergrade raw materials, measures to prolong the service life of blast furnaces and coke ovens, promotion of energy saving, use of wastes and solutions to environmental problems. This report outlines the condition of production and technological trends and technical development themes in ironmaking technologies.
RAR: reducing agent rate CR: coke rate PCI: pulverized coal injection PC: pulverized coal
() Australia South America India Others 1991 47 29 15 9 21 56 24 13 7 22 6 22 12 6 23 64 19 9 8 Low Robe Yandi Marra High PBrockman Mamba PBrockman Reserve (Mt) 27 3 52 69 9 T. Fe () 63.5 56.9 58.2 61.1 62.7 Al 2 O 3 () 2.1 2.8 1.4 2.3 2..15 mm () 12.7 3.6 2.8 21. 19. Combined water () 2.8 8. 1.2 6.3 4.1 (24 fy)
Charging device Inner volume Working volume Productivity RAR CR PCR Lance type Ore/Coke Blast temp. Blast moisture O 2 enrichment Top gas temp. Gas utilization CO (co) *2 Sinter ratio (SR) Pellet ratio (PR) TI (SI) Reduced degradation index (RDI) Reduced index (RI) Sinter SiO 2 Sinter CaO/SiO 2 Sinter Al 2 O 3 Sinter FeO Coke strength after reaction Coke ash Coke size DI 15 15 Pig temp. Pig Si Pig S Slag rate Slag Al 2 O 3 Slag CaO/SiO 2 m 3 t/m 3 d g/nm 3 mm 455 375 1.88 545.4 291 254.4 Double 5.43 1233 17 4.1 21 49.6 43. 35. 73 (89.6) 23.9 66.9 2.11 1.73 7.4 11.3 49.7 84.8 1496.48.21 265 15.2 1.25 *1 PW: Paulw Wurts, *2 co = CO 2 / (CO + CO 2 ) m 3 Kakogawa 1BF Bell 1998. 3 Fukuyama 3BF Bell 1998. 6 3223 2774 1.84 554.5 289 265.5 Double / Oxygen 5.46 122 32 4.8 251 46.5 76.7 15.5 66.3 47.5 71.5 4.21 2.7 1.61 5.22 11.9 49.75 (65) (DI 3 : 92.4) 151.34.27 266 13.8 1.28 Muroran 2BF PW *1 1998. 12 2296 1963 2.18 55.4 314 191.4 Single 5.17 1262 16.8 2.8 49.5 87.6 74.7 38.8 66.4 5.1 1.77 1.89 5.83 62 44.2 85.7 1514.66.15 39 15.9 1.26 Ijmuiden 7BF Bell 1999. 1 379 523 37 216 Single 1258 8 8.3 146 47.7 44.1 52.5 TI>5mm: 81.1 3.75 2.65 Al 2 O 3 +TiO 2 : 1.63 14.64 62.2 9.8.43.29 199 18.1 1.15 Bao steel 1BF Bell 1999. 9 463 2.2 51. 25. 26.6 (6.48) 1251 14 3.2 239 51. 72.8 7 35.1 69.5 4.56 1.83 1.49 7.47 11.3 5.8 87.7 151.3.21 255 14.3 1.21 POSCO 3BF PW *1 22. 1 3795 2.28 493. 271. 222.3 (5.98) 1138 6 2.8 83.1 4.9 (93.5) 39 1.5 6.47 67.7 11.4 52.1 88.1 1516.4.17 277 14.3 1.25
Inner volume Productivity RAR CR Tar, PCR Ore/Coke Blast temp. Blast moisture O 2 enrichment Top gas temp. co SR + PR RI (RDI) TI Sinter SiO 2 (FeO) Sinter Al 2 O 3 Coke ash Coke size DI 15 15 Pig temp. Slag rate Slag CaO/SiO 2 (Al 2 O 3 ) m 3 t/m 3 d g/nm 3 mm Fukuyama 3BF 1981. 11 3223 2.37 396 354 Tar 42.1 * 4.5 1353 73 54.8 96.6 + 68.9 (36.9) 6.3 5.1 (4.64) 1.8 9 52.3 DI 3 : 92.9 1481 274 1.28 (14) Tar injection Muroran 4BF 1981. 7 229 1.84 448 448 3.59 122 23 113 51.5 93.9 + 4.6 (31.3) 7.8 5.51 (5.55) 2.13 1.6 DI 3 : 95.4 1518 315 1.22 (14.9) All coke Oita 2BF Pohang 3BF 1994. 3 22. 1 5245 3795 2.19 2.28 454.7 493 356.3 271 PC 98.4 PC 222.3 4.52 * 5.98 1268 1138 2 6.5 19 28 53.3 78.5 + 7 83.1 + 4.9 68.1 (35.8) (39) 75.7 5.3 (5.53) (6.47) 1.61 1.5 1.7 11.4 47 52.1 85.7 88.1 1522 1516 287 277 1.23 (13.5) 1.25 (14.3) PC injection * Estimated
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Throat, shaft, belly, bosh Bottom Hearth side wall Other equipment Scheduled stop 1975 1985 43 11 29 36 1986 2 22 3 47 6 22 21 4 (5) 3
() 1991 cy 21 cy PCI 78 1 TRT* 91 1 Hot stove waste heat recovery 98 98 Waste heat recovery in sinter 56 72 CDQ 57 76 CMC or DAPS 28 61 *TRT: Top pressure recovery turbine
RAR CR PCR Tar Plastic Reducedore injection Base 428.15 386.5 42.1 Case 1 453 453 Case 2 443.5 345.5 98 Case 3 461.35 239.1 222.3 Case 4 455.5 255.1 15 5 Case 5 449.5 249.1 15 5 1 Case 6 43.5 23.1 15 5 1 Case 7 49.5 29.1 15 5 1 Case 8 377.5 227.1 15 (R: Prereduction degree =.7) Miscellaneous Shaft gas Nm 3 /t 1 1 348 (CO: 72, CO 2 : 1.5, H 2 : 11) Tuyere gas Nm 3 /t 216 (CO: 72, CO 2 : 1.5, H 2 : 11) SR Ore/Coke Blast temp. g/nm 3 Blast moisture Nm 3 /t Cold O 2 O 2 enrichment Top gas temp. H 2 co Coke ash Drop of pig temp. Slag Heat flux C sol. Shaft efficiency ( shaft) Temp. of thermal reserve zone Flame temp. Total coal rate Total carbon 8 4.13 125. 87 5 54.3. 282.836 11.4 95 2285.7 725.1 572.8 Tar injection 8 3.53 11 15. 72 5 53.4 3.2 295.839 12. 95 2242.4 792.7 626.2 (Muroran) All coke 8 4.63 125. 13 5 53.9 6.1 285.81 98.6 95 2216 724.3 572.2 (Oita) PC injection 8 6.71 125 3.67 197 5 52. 17. 278.758 83.7 95 216.3 685.3 541.4 (Pohang) PC injection 8 6.28 125 3.98 196 5 51.6 17.7 275.763 79.8 95 293.5 637.5 53.7 Plastic injection 8 5.82 125 7.43 198 5 49.5 25.4 252.755 63.9 95 249.9 617.4 + 487.8 + Plastic injection + Ore injection 68 5.74 125 25.34 198 5 48.2 28.2 189.932 32. 95 2265.8 565.2 + 446.5 + Plastic, ore injection + MFe 68 6.32 125 21.15 197 5 53. 4.4 185.912 25.7 85 2141.9 532.8 + 42.9 + Plastic, ore injection, MFe + High RI coke 8 7.8 225 79.1 166 5 43.1 32.6 268.779 19.1 1 95 2252.4 594.3 + 469.5 + Top gas recycling : carbon rate of producing prereduction ore : carbon rate of manufacturing O 2