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Global crude-steel output exceeded 1.85 Gt in 2023, driven by demand for high-strength automotive sheet, electrical steels and low-carbon construction grades.
Key trends: ultra-low inclusion levels (< 5 ppm total oxides), scrap-based electric-arc-furnace (EAF) routes, and stringent environmental regulations (ISO 14001, EU BAT).
“Every 1 ppm reduction in ferrous inclusions raises cold-rolled sheet fatigue life by 8–12 % and cuts downstream pickling acid use by 5 %.”
Magnetic separators remove tramp iron, scale and slag particles at every process stage, protecting rolls, reducing surface defects and lowering mill downtime costs.
Application | Separator Type | Key Specs | Feed State | Share | Reference Case |
Blast-furnace slag water-quench loop | Wet Drum LIMS | 0.25 T, Fe recovery 88 % | 15 % solids slurry, 45 °C | 25 % | ArcelorMittal Dunkirk 3 Mt/y tail-water pit |
BOF/EAF slag yard runoff | Suspended Plate Magnet, air-cooled | 0.6 T, IP65 housing | Clarified water 60 °C | 20 % | Nucor Gallatin scale-pit return |
Cold-rolling alkaline rinse | Electromagnetic Filter Grid | 0.9 T, 316L cladding | Caustic rinse 55 °C, pH 12 | 15 % | POSCO Gwangyang CR line |
Pickling-line rinse-water polishing | Rare-Earth Roll + Disk combo | 1.2 T, belt 1 m/s | Acid rinse 40 °C | 30 % | ThyssenKrupp Dortmund closed loop |
Mill-scale thickener underflow | Wet Drum LIMS | 0.18 T, Fe₃O₄ 65 % conc. | Slurry 30 % solids, 50 °C | 10 % | Tata Steel IJmuiden tailings pond |
● High-temperature tramp iron → Water-cooled ceramic magnet blocks withstand 1 200 °C splash; service life > 5 years.
● Micron-scale inclusions → Pulsed high-gradient matrix increases capture efficiency to 99.8 % at 20 µm.
● Sticky mill scale → Variable-frequency vibration + scrapers keep drum surface clean, cutting maintenance stops by 60 %.
● Steel grades: EN 10130, ASTM A1008 (inclusion rating ≤ 1.0)
● Safety: CE, IEC 60204-1, ATEX Zone 22
● Environmental: EU BAT-AEL, ISO 14001
● Capacity: 1 500 separators/year, 0.15–2.0 T field range in stock.
● Lead time: Standard models 6–8 weeks; emergency spares within 72 h.
● Inspection: In-line particle counters, magnetic-flux mapping every 6 months.
● Add-ons: Digital twin for scale build-up prediction, remote PLC diagnostics.
A European EAF mill producing 1.2 Mt/y of HSLA strip installed two rare-earth roll separators ahead of the tandem mill.
● Inclusion count dropped from 8 ppm → 3 ppm.
● Surface defect rate fell by 35 %, saving USD 2.4 M/year in downgrading losses.
● Project payback achieved in 11 months; continuous operation since 2022.