What materials can a magnetic separator remove
Jun 26, 2025
Magnetic separators excel at removing ferromagnetic materials and certain paramagnetic minerals, but cannot remove non-magnetic contaminants. Effectiveness depends on the separator's design and magnetic strength.
✅ Primary Targets (Strongly Attracted)
Ferrous Metals & Alloys (Easily captured with standard NdFeB magnets):
• Iron & Steel Particles (e.g., rust, tool wear fragments)
• Martensitic Stainless Steel (e.g., 400-series machining swarf)
• Low-Alloy Steel Fragments
• Cast Iron Particles
Capture Efficiency: 99%+ for particles >50µm using 8,000+ Gauss fields.
⚠️ Secondary Targets (Weakly Attracted)
(Require high-gradient fields from NdFeB/SmCo magnets or electromagnets)
Paramagnetic Minerals & Compounds:
• Magnetite (Fe₃O₄) • Ilmenite (FeTiO₃) • Hematite (Fe₂O₃) • Chromite (FeCr₂O₄) • Wolframite
Work-Hardened Austenitic Stainless Steel (e.g., 304/316 fragments after grinding)
Key: SmCo or high-purity NdFeB magnets (>12,000 Gauss) essential for sub-100µm weakly magnetic particles.
❌ Materials They CANNOT Remove
Non-Ferrous Metals: Aluminum, Copper, Lead, Zinc, Titanium
Non-Magnetic Stainless Steels: Austenitic grades (e.g., 304, 316) in annealed state
Plastics, Glass, Wood, Ceramics
Solution for Non-Ferrous: Pair with Eddy Current Separators.
Industry-Specific Contaminant Examples
| Industry | Typical Contaminants Removed | Separator Type |
|---|---|---|
| Food & Pharma | Iron filings, steel wool, 430SS fragments | Magnetic Rods, Pipeline Housings |
| Plastics Recycling | 410/420 stainless tool flakes, rust | Magnetic Grids, Drums |
| Mining/Minerals | Magnetite, pyrrhotite in silica/kaolin | Wet Drum Separators |
| Chemicals | Catalyst residue (iron oxide), reactor corrosion byproducts | Magnetic Filters |
| Ceramics/Glass | Mill scale, iron oxide specks in feldspar | Plate Magnets, Pulleys |
Critical Performance Factors
Particle Size:
500µm → Easily captured by 6,000 Gauss
50–500µm → Requires 8,000–12,000 Gauss (NdFeB/SmCo)
<50µm → Needs optimized high-gradient designs
Material Depth & Flow Rate:
Deep material beds → Suspended magnets with 15,000+ Gauss
High-speed conveyors → Self-cleaning magnetic pulleys
Magnet Grade:
NdFeB: Cost-effective for most ferrous capture
SmCo: Essential for hot/corrosive processes + weakly magnetic fines
Why MCI-Powered Separators Capture More
As a magnet supplier to separator OEMs, we enable superior performance:
Stronger Capture: 12,000+ Gauss surface fields for fine paramagnetics.
No Magnetic Decay: SmCo magnets retain >99.9% flux after 10+ years.
Harsh-Environment Kits: 316L stainless housings for acid washdown/pharma.
🔬 Real Result: MCI's SmCo rods increased magnetite capture in lithium ore processing by 62% vs. ferrite designs.
Need to Solve a Contamination Challenge?
→ For OEMs: Source high-Gauss NdFeB/SmCo for your separator designs.
→ For End-Users: Consult our engineers for system upgrades.
