NEEP602 Course Notes (Fall 1996)
Resources from Space

Extraction Techniques for Minerals in Space


Extraction Methods
Orebody shape is function of its mode of formation:

Mining depends on:

Open Pit/ Quarry


Broken ore occupies 30-50% more volume than parent material Cut and Fill: fill mined area with waste rock or cemented tailings
Sublevel or Block Caving Mining either by advancing from or retreating to the point of access In-situ recovery: possible for oil shale (burn front)
Borehole Extraction; Heap Leaching

Milling: "bust it up and classify it"
Resource Recovery in Space

Unconsolidated material at the Surface: Lunar regolith

Before going any further consider weight, mass, inertia, friction, traction
Asteroidal Mining:
Problems with automation or teleoperation Mining in zero gravity Possible solution:
  1. Cable the mining equipment to the small asteroid.
  2. The cable holds both the fracturing/removal equipment and the collecting `bag' to the surface of the asteroid. The bag maintains its shape because the asteroid is spinning; this spinning also helps collect the broken material into the bag.
  3. Material needs to be boosted with enough energy to pass the synchronous orbit limit so that centripetal force collects it into the bag.
  4. Blasting could be an alternative but would have to be done very carefully.

Extraterrestrial Mining Problems for Research:
  1. How should mechanical equipment be modified for operation in reduced gravity? (excavation, loading, moving)
  2. Remote and automated mining. What progress has been made on Earth?
  3. Environmental effects: extremes of heat and cold
  4. Applicability of terrestrial techniques to low gravity, no atmosphere situations.
  5. Rock drilling:
  6. conventional drilling: drilling mud? friction?
  7. melting and vaporization; chemical reaction; heat induced spalling; mechanical stress; spark cratering
  8. Changes in traction and how to compensate:
  9. traction is function of gravity and friction
  10. Changing role of blasting in low gravity settings; vacuum will also affect blast
  11. Wear resistant materials
  12. Particle size reduction in low gravity settings
  13. design of crushers; substitute for wet grinding and separating?
  14. classifiers


W. H. Dennen and B. Moore (1986) Geology and Engineering

W. H. Dennen (1989) Mineral Resources: Geology, Exploration, and Development

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