producing metal in space
byblow
produce steel (in space) from ores found on NEOs?
Would there be a need to add carbon (as a reducing agent) during the
refining process, or something with characteristics similar to
limestone (I believe calcium oxide is the "active ingredient" in
limestone)? Would oxygen be needed for a blast furnace? Would water
be needed to quench the hot steel?
Another question I have is, How would something like a mini-mill be
modified to function in zero-G and vacuum?
I had thought something like an electric arc furnace would be all
that's needed to refine pure iron/steel from NEO ores, but from what I
can find, EAFs appear to be used almost exclusivly for refining scrap
steel.
Keith Henson
> What equipment, materials and amount of electricity are needed to
> produce steel (in space) from ores found on NEOs?
It depends on the object. Some of them, 1986 DA for example, are
thought to be solid nickel-iron. Depending on what you wanted to do
with it, the material could be melted using an open ended induction
furnace, electromagnetically pumped out and rolled into I beams.
If you wanted the nickel, roll the metal into thin strips, and run it
though a number of gas lock stages into a 15 Bar (750 psi) long
chamber with warm flowing carbon monoxide. The nickle, iron and
cobalt carbonals can be sorted out of the gas stream and reduced back
to metals. See Mond process. The dust contains the rest of the
elements, including platinum group metals, gold and copper. Dr. John
Lewis, http://en.wikipedia.org/wiki/John_S._Lewis, has done a lot on
this topic.
> Would there be a need to add carbon (as a reducing agent) during the
> refining process, or something with characteristics similar to
> limestone (I believe calcium oxide is the "active ingredient" in
> limestone)? Would oxygen be needed for a blast furnace? Would water
> be needed to quench the hot steel?
Depends on what you are starting with, but generally no.
> Another question I have is, How would something like a mini-mill be
> modified to function in zero-G and vacuum?
Vapor deposition is one way to make sheet metal or other fabricated
items.
Sorting out non metallic inclusions may take some kind of induced g
forces.
> I had thought something like an electric arc furnace would be all
> that's needed to refine pure iron/steel from NEO ores, but from what I
> can find, EAFs appear to be used almost exclusivly for refining scrap
> steel.
I think induction is a better way to heat metal in space.
Keith Henson
byblow
> On Aug 25, 6:59 pm, byblow <pstur...@gmail.com> wrote:
>
> > What equipment, materials and amount of electricity are needed to
> > produce steel (in space) from ores found on NEOs?
>
> It depends on the object. Some of them, 1986 DA for example, are
> thought to be solid nickel-iron. Depending on what you wanted to do
> with it, the material could be melted using an open ended induction
> furnace, electromagnetically pumped out and rolled into I beams.
So the nickel-iron on a metallic NEO (like 1986 DA) is totally pure
and doesn't need to be refined? Does it become nickel *steel* after
it's melted?
Do you happen to know how many kilowatt hours it would take to melt a
tonne of nickel-iron using induction heating? How about to melt 100
tonnes?
Keith Henson
> On Aug 26, 8:30 pm, Keith Henson <hkeithhen...@gmail.com> wrote:
>
> > On Aug 25, 6:59 pm, byblow <pstur...@gmail.com> wrote:
>
> > > What equipment, materials and amount of electricity are needed to
> > > produce steel (in space) from ores found on NEOs?
>
> > It depends on the object. Some of them, 1986 DA for example, are
> > thought to be solid nickel-iron. Depending on what you wanted to do
> > with it, the material could be melted using an open ended induction
> > furnace, electromagnetically pumped out and rolled into I beams.
>
> So the nickel-iron on a metallic NEO (like 1986 DA) is totally pure
> and doesn't need to be refined?
It's hardly pure in the sense that it's got lots of different elements
in it and we don't yet have samples so we are not certain about what's
in it. As for needing to be refined, it depends on what you want to
use it for. Construction grade I beams, probably not.
> Does it become nickel *steel* after it's melted?
It's been melted, billions of years ago. As for what you call it,
steel is what we call iron reduce from ore and refined to specific
composition.
> Do you happen to know how many kilowatt hours it would take to melt a
> tonne of nickel-iron using induction heating? How about to melt 100
> tonnes?
It's easy enough to figure out. Iron is close enough to 56 g/mol. A
kg would be 17.8 mols. The specific heat is 25 J/mol/deg K. or 446 J/
kg/deg K. Iron melts at 1800 deg K. so figure heating it 1600 deg.
That would take ~714 kJ/kg. The heat of fusion is 13.8 kJ/mol or 246
kJ/kg, around 960 kJ/kg to heat and melt.
Given this is rough use 1000 kJ/kg. A kJ is a kW-s, so a 1000 kW (a
MW) would heat and melt a kg/s. Over an hour it would melt 3600 kg or
3.6 tons per MW per hour. 100 tons would take 27.8 MWh to melt.
This doesn't consider the thermal radiation loss from the induction
furnace.
In the context of a serious mining project, a kg/s doesn't amount to
much. The Morenci mine in Arizona processes a million tons per day or
around 11,000 kg/s.
A 5 GW power satatellite using 1 GW for the induction furnace would
melt 1000 kg/s. The estimated mass is 2 x 10^13 kg so at this rate it
would take 2 x 10^10 s to use it up or 634 years.
Dr J R Stockton
bn.googlegroups.com>, Mon, 29 Aug 2011 23:07:23, byblow
<pstu...@gmail.com> posted:
>So the nickel-iron on a metallic NEO (like 1986 DA) is totally pure
>and doesn't need to be refined? Does it become nickel *steel* after
>it's melted?
>
>Do you happen to know how many kilowatt hours it would take to melt a
>tonne of nickel-iron using induction heating?
The figures necessary for a reasonable estimate are easily found in
<http://en.wikipedia.org/wiki/Iron>.
> How about to melt 100
>tonnes?
About a hundred times as much.
There ought to be research on what useful can be made just by casting
from a melt of metallic or stony asteroid material. For many purposes,
ISTM, refining would be an unnecessary refinement.
--
(c) John Stockton, nr London, UK. ?@merlyn.demon.co.uk Turnpike v6.05 MIME.
Web <http://www.merlyn.demon.co.uk/> - FAQqish topics, acronyms and links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News.
lindajamison76
'Dr J R Stockton[_127_ Wrote:
> ;1172044']In sci.space.tech message
> abcbfb6e-6d12-4cb1-b7a5-2459d2c2d030@l2g2000v
> bn.googlegroups.com, Mon, 29 Aug 2011 23:07:23, byblow
> pstu...@gmail.com posted:
> -
> and doesn't need to be refined? Does it become nickel *steel* after
> it's melted?
>
> Do you happen to know how many kilowatt hours it would take to melt a
> The figures necessary for a reasonable estimate are easily found in
> http://en.wikipedia.org/wiki/Iron.
> About a hundred times as much.
>
>
> There ought to be research on what useful can be made just by casting
> from a melt of metallic or stony asteroid material. For many purposes,
> ISTM, refining would be an unnecessary refinement.
>
> --
> (c) John Stockton, nr London, UK. ?@merlyn.demon.co.uk Turnpike v6.05
> MIME.
> Web http://www.merlyn.demon.co.uk/ - FAQqish topics, acronyms and
> links;
> Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm,
> etc.
> No Encoding. Quotes before replies. Snip well. Write clearly. Don't
> Mail News.
--
lindajamison76