FeSi is combustible in pure oxygen with the Fe burning with about 3000 BTU/lb. and the silicon with about 13,000 BTU/lb. If ground up it could make a powerful fuel that's easily stored. LOX would also have to be stored underground. Most metal smelting systems also produce oxygen, and what will we do with it all?
Thermite was once used to smelt chromite. If there are chromite deposits in the Moon we might, just might use thermite because we could produce thermite with direct application of solar energy to make aluminum by solar carbothermal reduction and FeO can literally be boiled out of regolith at 1200 C. There are other thermite compositions, some of them made with magnesium another metal we can make by direct app. of solar energy. Thus, we might find this to be more efficient than an electric arc furnace. Chromite could also be smelted with direct app. of solar energy.
If dayspan producion of Al, Mg and FeO is high enough, we could do some smelting at night. Of course, the economics of this must be determined thru actual experience on the Moon.
Some might think burning ferrosilicon, FeSi, is wasteful and foolish. Rather than do something so primitive we are likely to have superconducting energy storage systems for nightspan power in coming decades. Ferrosilicon is actually a very useful substance. It can be used for 1) transformer cores 2) MgO reduction 3) possibly as a Moon makeable cathode for magma electrolysis furnaces* and 4) corrosion resistant chemical vessels, pump rotors, etc. |
