Magnetic Beneficiation Stage
High-Gradient Magnetic Separator for Ferrous-Mineral Concentration
The magnetic beneficiation stage is a high-gradient magnetic separator that uses 1.5-tesla samarium-cobalt permanent magnets and a ferromagnetic wire matrix to extract iron-bearing minerals—including ilmenite, agglutinates, and nanophase iron—from lunar regolith at 30 kilograms per hour. To withstand the high-temperature lunar environment without demagnetizing, the system utilizes samarium-cobalt magnets with an 825 °C Curie temperature. The separation leverages nanophase iron formed by solar-wind reduction in mature regolith, achieving a 90% ferrous capture efficiency, while the lunar vacuum prevents oxidation on the internal capture wires during feedstock preparation for downstream chemical and electrostatic processing.
High-gradient magnetic separator (HGMS) using rare-earth permanent magnets or electromagnets to extract paramagnetic and ferromagnetic minerals (ilmenite, nanophase iron particles, agglutinates) from regolith feedstock, complementary to the electrostatic stage.
Purpose
Remove iron-bearing minerals — either as a beneficiation enrichment of ilmenite for downstream chemistry, or as a depletion step before anorthite enrichment in the electrostatic stage (since iron contamination harms calcium/aluminum extraction).
Context
Operates in tandem with L3-ISR-BEN-ELEC per AIAA SciTech 2024 architecture — magnetic stage first removes ferrous fraction, then electrostatic stage refines remaining non-magnetic fraction. Feedstock from L3-ISR-BEN-SIZE; outputs to L1-MFG and L1-WMS.
Principles
- ▸Paramagnetic minerals (ilmenite) attracted by field gradient; ferromagnetic agglutinates (nanophase Fe) strongly captured
- ▸High-gradient magnetic separation (HGMS): regolith flows past array of fine ferromagnetic wires inside strong field — gradient at wires captures susceptible particles
- ▸Permanent magnets (NdFeB, SmCo) provide ~1.5 T at pole faces; electromagnets to ~5 T for higher selectivity
- ▸Lunar nanophase iron (npFe) embedded in agglutinates and rims provides 'free' magnetic susceptibility — present in all mature regolith
- ▸Susceptibility ranking: iron metal > agglutinates > ilmenite > olivine > pyroxene > plagioclase
- ▸Multi-pass cascade: each magnetic stage removes another increment of ferrous content
Typical implementations
- ▸Eriez HGMS terrestrial industrial systems (heritage)
- ▸AIAA SciTech 2024 (10.2514/6.2024-2539) — tandem magnetic + electrostatic for lunar simulant
- ▸NASA STMD calcium/aluminum beneficiation — magnetic stage removes iron for feldspar enrichment
- ▸Frontiers Space Tech ilmenite enrichment optimization (2023)
- ▸Permanent-magnet HGMS for mobile mining applications (terrestrial)
- ▸ESA Lunar Volatiles Mobile Instrumentation magnetic samplers
Lunar considerations
- ▸All lunar regolith carries nanophase iron from solar-wind reduction — moderate magnetic field can extract significant fraction
- ▸SmCo permanent magnets preferred for high-temperature lunar environment (Curie ~825 °C vs. NdFeB ~310 °C)
- ▸Vacuum + dry environment ideal — no rust on magnetic wires
- ▸Long-mission magnet degradation: SmCo loses <1% strength per decade at 100 °C
- ▸Cleaning cycle (back-flush or vibration) periodically removes accumulated magnetic particles from capture matrix
- ▸Vacuum-tight enclosure prevents stray particle escape
Specifications
Functional
| primary function | Magnetic separation of ferrous minerals from regolith |
| inputs | Sized regolith feedstock from L3-ISR-BEN-SIZE, Cleaning-cycle power from L1-PDM (vibration / back-flush) |
| outputs | Magnetic concentrate (ilmenite + nanophase Fe agglutinates), Non-magnetic tailings to L3-ISR-BEN-ELEC for further concentration, Process telemetry: throughput, magnetic fraction percentage |
| magnetic field strength t | 1.5 |
| throughput kg per hour | 30 |
| ferrous capture efficiency percent | 90 |
| ilmenite concentration factor | 5 |
| cleaning cycle interval hr | 4 |
| power consumption w | 50 |
| magnet type | SmCo permanent (with electromagnet boost optional) |
Physical
| mass kg | 25 |
| dimensions | 0.8 × 0.4 × 0.4 m |
| materials | SmCo (samarium-cobalt) permanent magnet stack, Stainless 430 ferromagnetic capture-matrix wires, 316L stainless non-magnetic chassis, PEEK / PTFE feed chute lining (low wear), Vibrator motor for cleaning cycle, Hermetically sealed enclosure |
| operating temperature c | -40, 100 |
| vacuum compatibility | True |
Operational
| power consumption w | 50 |
| thermal range c | -40, 100 |
| lifetime years | 20 |
| mtbf hours | 60000 |
Interfaces
Provides
- Magnetic concentrate for downstream iron/titanium chemistry
- Ilmenite for H2 reduction to make O2
- Non-magnetic fraction for electrostatic anorthite enrichment
- Magnetic fraction percentage
Requires
- Size-sorted regolith feedstock
- Cleaning-cycle vibrator power (~50 W)
Cite this entry
Lunar Ark Codex. "Magnetic Beneficiation Stage" (L3-ISR-BEN-MAG). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-ISR-BEN-MAG
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.