[ExI] Lunar dirt

Adrian Tymes atymes at gmail.com
Fri Jan 7 03:01:59 UTC 2011


On Thu, Jan 6, 2011 at 5:21 PM, Keith Henson <hkeithhenson at gmail.com> wrote:
> Will someone enlighten me about what remote manipulators on the moon
> are going to be doing?
>
> You don't have a lot to work with; lunar dirt is about as far from
> useful objects as I can imagine.
>
> I have followed this topic since the mid 1970 and, far as I know,
> there was never a believable flow chart with rock going in and useful
> stuff coming out the other.
>
> Take solar cells.  Anyone have an idea of what sort of plant it takes
> make silicon?  What inputs the plant takes?  What has to be frequently
> replaced?

Materials processing is a bit of a science in its own, but fortunately, it is
well enough established in this regard that the details rarely need to be
looked at.  (Still, it's a good question to ask, to make sure that there is a
solution here.)

For one example, take olivine, a material native on the moon.  From
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B984K-4W0SFYG-SF&_user=10&_coverDate=02%2F28%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1598942661&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=7530ee67e2981bcaba741394c3faeb26&searchtype=a
we see that water and carbon dioxide can catalyze its breakdown into
silicon dioxide (silica) and magnesium oxide (a waste product as far
as this example process is concerned, but with potential side uses).

Silicon dioxide can be reacted with carbon - in coal or charcoal form -
and heat like so: SiO2 + C -> Si + CO2

This provides the carbon dioxide for the previous step.  Water, in the
form of ice, has been found on the moon - though it may be precious,
it is usable for this.

Carbon dioxide, further water, and sunlight can be reacted in plants
to split the carbon from the oxygen.  Excess plant material can be
burned (preferably in a low-oxygen process) to make more charcoal.

There are probably better ways to do it, and certainly olivine is not the
only type of rock that can be processed, but this gives you one example
of inputs and outputs.

Energy is, of course, consumed at various stages of this process.  A
power source will be needed at first, but possibly not a very long lived
one, if this process can make and place (with those manipulators)
solar panels to power itself further.  (It is likely that such a factory
would be its own first customer, as a practical matter.)




More information about the extropy-chat mailing list