Refueling the fleet

[HG_B]

I
If you take a meter thick piece of ice, 100 meters wide, it's 5.6Km long. That's a lot of ice. And it's only 0.7% Hydrogen,

???

The density of H in H2O is higher than L-Hyd.

 

[aramis]

???

The density of H in H2O is higher than L-Hyd.

Also in several other chemicals. LHyd is a very inefficient way to store hydrogen, especially long term.

 

[Carlobrand]

Also in several other chemicals. LHyd is a very inefficient way to store hydrogen, especially long term.

Yeah, but it's ... but ... umm ...

I got nothing. That was just a silly oversight on their part. They coulda used water, stored the O2 after cracking free the hydrogen, then used the O2 to combine with H2 when refueling to improve storage efficiency.

 

[Carlobrand]

...But ice mining? That needs some specialized gear. It's not parts of the crew walking off the shuttle with picks and wheel barrows. ...

It's an engineering problem. At the small end of the ship scale, the 100 dT scout's dumping heat from a power plant generating more power than we use here in the second largest city in New Mexico - which admittedly doesn't trend toward large cities, but you get the idea.

My sniggling suspicion is that between the available power and the heat output of these ships, solving the ice mining problem with the resources available to the typical ship is not going to create a major engineering hurdle at TL 9+.

 

[mike wightman]

Has anyone considered looking at the actual rules for mining asteroids?

CT Beltstrike boxed adventure.

 

[aramis]

Yeah, but it's ... but ... umm ...

I got nothing. That was just a silly oversight on their part. They coulda used water, stored the O2 after cracking free the hydrogen, then used the O2 to combine with H2 when refueling to improve storage efficiency.

There's one reason of import for a fusion system to store hydrogen as LHyd rather than other hydrogen-bearing compounds... mass efficiency. 1 Ton of Hydrogen as LHyd masses 1 ton plus container, and 14.1±0.1kL, exact volume varying by pressure and temperature.

1 Ton of Hydrogen as dihydrogen monoxide (water) masses 9 tons plus container... but loses almost none to container penetration, and takes only 1±0.02 kL, and can be stored at room temperatures.

 

[HG_B]

but loses almost none to container penetration, and takes only 1±0.02 kL, and can be stored at room temperatures.

I'll try to find the link but there was an interesting, accidental materials discovery this year. A molecular thin carbon coating was made that totally stopped He atoms and only allows H2O to freely pass. (very weird needless to say) One of the scientists "capped" a bottle of liquor for kicks to further distil it as water passed but the alcohol couldn't penetrate.

By TL 9 or 10 I'm pretty certain that we'll be able to stop Hy migration in a similar fashion.

Just an interesting aside.

 

[McPerth]

There's one reason of import for a fusion system to store hydrogen as LHyd rather than other hydrogen-bearing compounds... mass efficiency. 1 Ton of Hydrogen as LHyd masses 1 ton plus container, and 14.1±0.1kL, exact volume varying by pressure and temperature.

1 Ton of Hydrogen as dihydrogen monoxide (water) masses 9 tons plus container... but loses almost none to container penetration, and takes only 1±0.02 kL, and can be stored at room temperatures.

(emphasis is mine)

Just for clarity, This is the volume for 1 metric ton of water. To have the full ton of hydrogen, being 9 tons of water, you need 9 times this volume (still less than 1 ton of LHyd).

 

[whartung]

It's an engineering problem. At the small end of the ship scale, the 100 dT scout's dumping heat from a power plant generating more power than we use here in the second largest city in New Mexico - which admittedly doesn't trend toward large cities, but you get the idea.

Of course it's an engineering problem, but it's not simply a power problem.

Seems to me that mining water in vaccum has distinct challenges.

How do you break the ice? How do you convert it to water? How do you pump the water?

Water doesn't stay liquid very long at -100 degrees in a vaccum. And it's not like you can suck it up. And working in a low or zero G environment doesn't help.

I can see erecting a pressurized vessel on top off ice. You then heat a melt the water. But that seems pretty dangerous. Much less getting a vaccum tight seal in to the surface.

Then there is simply the volume involved. It's a lot of ice that needs to be processed. I don't see random scout ship having the crew or gear to perform the process. Maybe on a normal world (like in the Arctic). But not on a random asteroid.

 

[Greylond]

Here's a link to an article called The Deimos Water Company which discusses mining Mar's moon Deimos for water. A good part of the article is about the delta-V needed to get from LEO to Mars orbit but it has a good part about mining for water.
http://www.spacefuture.com/archive/the_deimos_water_company.shtml

I came across it due to playing a board game called High Frontier which was designed by a Rocket Scientist who has studied space exploration for a few decades.

High Frontier entry at Board Game Geek;
http://boardgamegeek.com/boardgame/47055/high-frontier

 

[HG_B]

Then there is simply the volume involved. It's a lot of ice that needs to be processed. I don't see random scout ship having the crew or gear to perform the process. Maybe on a normal world (like in the Arctic). But not on a random asteroid.

Probably the way it would be done in an emergency situation is: EV with laser rifle/carbine. Slice off manageable chunks & pack the cargo hold. Turn on grav & melt. Floor drains to fuel purif plant.