Regolith Processing

Complete raw material processing cycle: from regolith to finished materials.

TipMRE Technology Validation

Molten Regolith Electrolysis (MRE) is not a theoretical concept but a technology at TRL 6-7:

  • NASA KSC (2024): MRE cell testing in the ASSIST chamber under simulated lunar conditions
  • Lunar Resources: Processing 25 kg of regolith over 36 hours with measured oxygen yield
  • Blue Origin (Blue Alchemist): Complete MRE cycle with Fe/Si/Al purification and solar cell production. CDR passed (September 2025) — per NASA standards, CDR corresponds to ≥TRL 6
  • Sierra Space (2024): Carbothermal O₂ extraction in a thermal vacuum chamber

NASA quote: “Both Carbothermal Reduction and MRE have demonstrated operation under simulated lunar conditions to TRL 5/6” (category-wide assessment; Blue Origin specifically — ≥TRL 6)

Details: Technologies and Sources

Process Overview

Technology Cycle: Factory Equipment

Physical chain of units with IDs from the database:

flowchart TD
    %% EXTRACTION AND PREPARATION
    KROT[Mole] -->|dump| BUN[Hopper]
    BUN -->|regolith| SEP[Mag. Separator]
    BUN -.->|large chunks| GR[Vibrating Screen]
    GR -.->|>5 cm| DR[Crusher]
    DR -.->|chute| SEP

    %% SEPARATION - splitting into 2 streams
    SEP -->|36 t| MAGN[Magnetic Fraction]
    SEP -->|564 t| NMAG[Non-magnetic Fraction]

    %% FLOW DISTRIBUTOR
    NMAG --> SPLIT[Flow Splitter]

    %% PROCESSING LINES
    subgraph LINES[Processing Lines]
        direction TB

        subgraph TITANIUM[Titanium Line]
            SF3[Sublimation 450C]
            SF3 -->|chute| TI_OX[Calcination 900C]
            TI_OX --> TI_OUT[Titanium dioxide + sulfur]
        end

        subgraph GLASS_LINE[Glass Line]
            SF1[Small Furnace 1400C]
            SF1 -->|melt| FILT[W Bushings]
            FILT --> FIBER[Fiber 28 t]
        end

        subgraph MRE_LINE[MRE Line]
            SF2[Solar Furnace 1500C]
            SF2 -->|melt| MRE[MRE Cell]
            MRE --> O2[Oxygen 250 t]
            MRE --> FESI[Iron-silicon 35 t]
            MRE --> SLAG[Slag 251 t]
        end
    end

    %% Links from separation to furnaces
    MAGN -->|chute| SF3
    SPLIT -->|28 t| SF1
    SPLIT -->|536 t| SF2

    %% DISTILLATION
    SLAG -->|pipe| EQU024[Induction Furnace]
    EQU024 --> EQU031[Condenser K]
    EQU031 --> EQU032[Condenser Na]
    EQU032 --> EQU033[Condenser Mg]
    EQU033 --> AL_OUT[Aluminum 42 t]

    %% Styles
    style TITANIUM fill:#a8d4e8
    style GLASS_LINE fill:#b8e0d2
    style MRE_LINE fill:#e8a8d4
    style SPLIT fill:#ffe4b5

Materials Output (600 t regolith/day)

Product t/day % Source Application
Oxygen (O₂) 250 42% MRE Dome atmosphere, oxidation
Fe-Mn steel ~11 2% MRE + titanium Frames, rails, tools
Ferrosilicon -> Si 35 -> 25 6% MRE -> zone refining Electronics, solar panels
Aluminum (Al) 42 7% Distillation Mirrors, motor windings
Magnesium (Mg) 48 8% Distillation Al-Mg alloys, MgO ceramics
NaK coolant ~5 1% K + Na Electronics cooling
Sodium (Na) ~18 3% Distillation NaS batteries (anode)
Sulfur (S) 18 3% Titanium line NaS batteries (cathode)
TiO₂ 3 0.5% Titanium line Mirror electrochromics
Glass fiber 28 5% Silicates (SiO₂ + Al₂O₃ + CaO) Insulation, composites
Carbon (C) (~6) — Phase 2 (not in balance) Hadfield steel, anodes
Waste/slag ~143 24% Distillation 138 + titanium 5 Fill, ballast

Notes:

  • Fe-Mn steel: Iron from Mercury contains ~6% Mn - this is automatically a low-alloy steel (MESSENGER)
  • Ferrosilicon: Si exits MRE together with Fe. Purification via zone refining (35 t -> 25 t pure Si)
  • NaK: Eutectic 78% K + 22% Na, liquid at -12C - ideal coolant for space
  • Oxygen: Not for breathing (no humans) - for dome atmosphere (0.1 atm O₂) and chemical processes
  • Carbon: Phase 2 - requires separate factories at LRM deposits (not included in 600 t balance).
  • CaO (calcium oxide): ~10% of regolith (~60 t/day) — not reduced in MRE (Ca is too reactive). Partially used: ~3 t/day for glass fiber (flux) and WAAM fluxes. Remainder (~57 t/day) stays in final slag (fill, ballast).

Reception and Crushing

Dirty zone - VACUUM.

Critical condition: All processes are completely atmosphere-independent.

Regolith Preparation

Mercury regolith is the product of billions of years of meteorite bombardment. Average particle size 40-100 microns, 95% of material is already finer than 1 mm. Regolith goes directly to magnetic separation.

Optional: For deep drilling into bedrock, screen and crusher are used.

Vibratory Feeder (Transport)

Parameter Value
Drive Electromagnet
Principle Tray vibrates finely (50 Hz), material “flows”
Advantage No bearings or friction parts

Electromagnetic Vibrator Operating Principle

An electromagnet is a coil with an iron core. When current flows, a magnetic field is created that attracts the armature.

Operating cycle (50 Hz AC):

  1. Current in coil -> magnet attracts armature -> tray shifts
  2. Current = 0 -> springs return tray
  3. Current reverses sign -> attraction again (magnet works on |I|)
  4. Result: 100 oscillations/sec (frequency doubles)

Why material “flows”: - When tray moves up-forward, particles are thrown - When tray moves down-backward, it moves away from under the particles - Particles land slightly ahead -> micro-jumps sum into flow

Design for Mercury

Vacuum advantages: - No friction wear (no atmosphere = no oxidation) - No bearings - nothing to lubricate - Simple control - voltage adjustment changes amplitude

Earth analogs: Eriez, Syntron electromagnetic feeders - standard in food, pharmaceutical, and mining industries since the 1950s.

Melting and Separation

Hot zone - VACUUM.

The chemical reactor sits on open ground. Vacuum serves as ideal thermal insulation.

Magnetic Separation

Operating Principle

Material separation by magnetic properties. Mercury regolith contains two types of minerals:

Type Share Minerals Magnetic Properties
Magnetic 5-6% Ilmenite (FeTiO₃), troilite (FeS) Paramagnetics - attracted to magnet
Non-magnetic 94% Silicates (Si, Al, Mg, Ca, O) Diamagnetics - weakly repelled

In a 0.5-1.5 T magnetic field, paramagnetic minerals (containing Fe) are attracted to the magnet, while silicates are not. This allows stream separation.

Drum Separator Design

flowchart TD
    subgraph INPUT["FEED"]
        R[/"Regolith<br/>25 t/hour"/] --> VJ["Vibratory Feeder<br/>(electromagnetic)"]
    end

    subgraph SEPARATOR["DRUM SEPARATOR"]
        VJ --> DRUM["Drum dia 800x1200mm<br/>rotation 20 rpm"]
        DRUM --> |"electromagnets<br/>inside drum"| MAG["Magnetic Zone<br/>0.5-1.5 T"]
        MAG --> SCRAPER["Scraper<br/>(magnetic fraction removal)"]
    end

    subgraph OUTPUT["SEPARATION"]
        SCRAPER --> M[/"Magnetic Fraction<br/>FeS + FeTiO3<br/>1.5 t/hour"/]
        DRUM --> |"falls down"| NM[/"Non-magnetic Fraction<br/>silicates -> MRE<br/>23.5 t/hour"/]
    end

    style SEPARATOR fill:#e8d4a8
    style M fill:#c0c0c0
    style NM fill:#f5deb3

Parameters

Parameter Value
Type Drum with electromagnets
Drum diameter 800 mm
Drum length 1200 mm
Field strength 0.5-1.5 T
Rotation speed 20 rpm
Capacity 25 t/hour (600 t/day)
Mass 500 kg
Power 20 kW

Electromagnetic scraper: Metal strip moves left-right on electromagnetic guides. No friction, no bearings - nothing to wear.

Earth analogs: Eriez DR Drum Separator, STEINERT MT - used in mining for magnetite and ilmenite separation.

Processing Lines

After magnetic separation, material is distributed to specialized lines.

Flow Splitter

Non-magnetic fraction (564 t/day) is distributed between glass and MRE lines by a simple mechanical splitter:

  • 5% (28 t) -> narrow outlet -> glass fiber line
  • 95% (536 t) -> wide outlet -> MRE line

The 1:19 ratio is set by outlet geometry. No electronics - pure mechanics.

Lines Summary Table

# Line Input t/day Output
3.1.1 Glass Fiber Silicates (5%) 28 SiO₂ fiber
3.1.2 MRE Electrolysis Silicates (95%) 536 O₂ 250t, Fe/Si 35t, slag 251t
3.1.3 Distillation MRE slag 251 Al 42t, Mg 48t, Na 20t, K 3t, slag 138t
3.1.4 Titanium Line Magnetic fraction 36 TiO₂ 3t, S 18t, Fe 10t, waste 5t
3.1.5 Carbon (opt.) LRM regolith 200 Graphite ~6t

*Distillation processes slag from MRE, not input regolith - this is a sequential, not parallel line.

Wall Transit

Circulatory system.

How to transfer melt (1500C) through a cold crater (-150C) into the factory without losing atmosphere?

Electromagnetic Input with Active Insulation

A pipe with liquid metal passes through the dome’s airlock panel.

Physics: Pipe is a “sandwich” (Ceramics + Inductors + MLI).

Component Function
MHD pump Magnetic field pushes metal. No moving parts inside the pipe
Plug Made of the metal itself - provides sealing

U-shaped Hydraulic Seal (Siphon)

The pipe makes a deep bend downward.

Element Function
Principle At the bottom of the U-tube there is always a “plug” of heavy liquid iron, blocking gas escape from the dome
Emergency system Ceramic gate valve (slide gate) automatically cuts the channel when metal level drops

Casting Unit

Buffering and dosing - INSIDE DOME.

Critical problem: electrolysis runs continuously, but casting is batch. A buffer is needed.

Tundish

Intermediate vessel between MHD input and crystallizer.

Parameter Value
Capacity 2-3 tonnes of melt
Material Steel shell + refractory lining (magneite MgO)
Heating Induction (maintaining 1550C temperature)
Function Buffering, composition averaging, inclusion flotation

Localization: Magnesite (MgO) is produced from local regolith magnesium (8% content, ~48 t/day). Steel shell - from local Fe-6%Mn iron.

Appendix: Screen and Crusher

Optional equipment for working with bedrock during deep drilling.

Vibrating Screen

The “Mole” robot dumps material onto an inclined grate.

Parameter Solution
Drive Unbalanced motors (inertia)
Dust Does not hang as a cloud - falls straight down (ballistics). Filters not needed
Cooling Conductive (through frame metal)

Why Dust Does Not Float in Vacuum?

On Earth, fine particles “float” in air due to aerodynamic drag - air molecules slow the fall. In vacuum there is no air, so:

  • All particles (from boulders to micron dust) fall with the same acceleration
  • On Mercury g = 3.7 m/s² - a particle travels 1 meter in ~0.7 seconds
  • Trajectory is a pure parabola (ballistics), like a thrown stone
  • Dust does not form clouds - it simply falls

Consequence: Filters and dust suppression systems are not needed. This radically simplifies equipment.

Analogy: Apollo experiments showed that lunar dust behaves like sand - it pours and settles instantly.

Unbalanced Motors

The simplest way to create vibration is to attach an eccentric weight to the motor shaft.

Component Function
Electric motor Standard induction, ~3000 rpm
Eccentric Asymmetric weight on shaft
Centrifugal force F = mw²r - creates vibration

Principle: During rotation, the eccentric’s center of mass is offset from the axis -> centrifugal force arises -> motor housing “shakes”. Two motors rotating in opposite directions create directed vibration.

Advantages:

  • No wearing parts except bearings
  • Works in vacuum without modifications
  • Amplitude is adjusted by changing eccentric mass

Earth analogs: Martin Engineering, VIBCO vibrators - used in mining for decades.

Induction Motor Design

The induction motor is the workhorse of industry. On Mercury, it is adapted to local materials and vacuum:

  • Windings from aluminum - no copper on Mercury (MESSENGER), Al has 60% conductivity of Cu -> motor is 20-30% heavier
  • Bearings ceramic Al₂O₃ (corundum) - work without lubrication in vacuum, 100% local production
  • Cooling conductive - fan not needed, no convection in vacuum

Factory capacity: Producing ~10 t iron and 42 t aluminum per day, the factory can produce hundreds of motors/day - significant surplus.

Conductive Cooling

In vacuum there is no air -> no convection. Heat escapes only two ways:

  1. Radiation - radiators “shine” into space
  2. Conduction - heat flows through solid body contact

For the screen, the second method is used:

Element Temperature
Motor (operating) +80…+150C
Frame (massive) Intermediate
Crater floor ground -150C (permanent shadow)

Heat flow: Motor -> bolts -> frame -> supports -> ground. Cold ground works as infinite heat sink.

Alternative: Radiator panels radiating toward space (3 K). But for mechanical equipment, conduction is simpler.

Jaw Crusher

Parameter Value
Principle Mechanical plate compression
Plate material Low-alloy steel (Fe-6%Mn)
Vacuum advantage No corrosion - longer service life
Plate life ~2-3 months, then replacement

Manganese in Mercury Iron

Parameter Value
Mn content in crust ~0.1% (MESSENGER data)
Mn output ~600 kg/day (from 600 t regolith)
Mn content in iron ~6% (600 kg Mn / 10000 kg Fe)

Conclusion: Iron from Mercury already contains ~6% manganese - this is low-alloy steel with improved mechanical properties. Manganese is reduced together with iron during MRE electrolysis (Mn density is similar to Fe), requiring no separate process.

Crusher plate consumption:

Parameter Value
Plate set mass ~400 kg
Replacement Every 2-3 months
Consumption ~1.6 t/year
Share of Fe production 0.04% (at 3650 t Fe/year)

Conclusion: Fe-6%Mn plates wear faster than Hadfield steel, but consumption is so low (0.04% of iron production) that metallurgy complexity is not justified.

Equipment (Screen and Crusher)

See Also