G.D. Vialle
Lunexus Space, LLC,
United States
Keywords: orbital recycling, orbital manufacturing, satellite reclamation, semiconductors
Summary:
Arachne Station concept presents a novel analysis and solution to recycling orbital debris to output metal wire, protective shield material for orbital stations and silane gas for on-orbit manufacturing of semiconductors. At present, orbital debris is primarily in the form of defunct satellites, their subassemblies, and parts, located in various Earth orbits. We target silicon photovoltaics (PV), primarily in Low Earth Orbit (LEO). Spacecraft comprise many materials. By a satellite’s end-of-life, many components will have been degraded by solar radiation, and most of the electronics technologically obsoleted. Arachne presents a cost effective infrastructure for satellite disassembly and reclamation of space grade metals, electronics and photvoltaics. With adequate processing, orbital materials can most economically be used in space by other space manufacturers, which relieves the high cost per kilogram of launching materials from Earth. The typical recycling process on Earth iterates cycles of mechanical separation, sorting, aggregation, and thermochemical refinement. On-orbit satellite reclamation will be similar, but can leverage the abundant solar power, vacuum environment and microgravity. Arachne’s novel process for metals recycling replaces billets, commonly used as an intermediate product in terrestrial wire production, with the beads-on-strand system (BOSS), which in a fashion mimics arachnid web spinning, and ouputs metal wire spools which may be distributed for use in additive manufacturing on orbit. After structural metals, the largest components of a typical satellite are most commonly PV, electronics, and batteries. Of these, PV is arguably the simplest to process. Most legacy PV (including the majority of ISS power systems) is silicon based and often has substrate and coating of silica glass (SiO2). Hence, this proposal targets silicon which can be manufactured readily into silane gas (SiH4), with a bulk byproduct where impurities are inconsequential: powdered silica filler (PSF). Silane gas is an essential and ubiquitous precursor in the manufacture of thin film semiconductors. Due to the abundance of vacuum in near earth space, semiconductor manufacturing (which utilizes vacuum in several of its essential processes) is a top candidate for orbital manufacturing. Silane gas will be a high demand feedstock for this industry. Semiconductor demand is currently (as of 2022) outstripping supply, and it is entirely conceivable that this may be a rare opportunity for an orbital product to find profit in a terrestrial market. In the nearer term, however, the essential demand will likely be for on-orbit manufacture of PV to power the growing manufacturing industry in space. The PSF byproduct (essentially sand) from the silane reactor can be captured into tubular aramide bags, which can be used on orbit for ballistic and radiation protection when attached to the outside of space stations.