Hydrogen and Helium Mining

[AlexanderSen]

How would one go about mining hydrogen or helium in a realistic way given our current state of technology? I have read that there is an abundance of helium 3 on the surface of the moon, and Hydrogen is abundant through out the universe. Is one or the other of these elements more plausible and easier to mine than the other? Also, what kind of machines and processes are necessary for this to work?

 

[Serendipity]

Helium three is of most interest as it would be used for fusion reactions and hence energy generation. A lot of work has been done on the helium three - sweeping it up off the surface of the Moon and using spacecraft to skim the atmospheres of Uranus and Neptune to gather it (not Jupiter or Saturn because of their gravities).

There is a natural third place to look for it - but I'm keeping that up my sleeve as it's the subject of a short story I have written.

 

[SilentRoamer]

In SF you tend to see a lot of asteroid mining which might make sense given the following:

1. You don't need to worry about environmental damage.
2. You have a huge amount of resource in the Asteroid belt.
3. Probably the biggest plus would be fuel efficiency. Mining down a gravity well means a lot of resource is going to be used for entry and exit, even the smaller Gas Giants are going to take sufficiently more fuel to reach escape velocity.

Depending on the technology you are going to use the Sun could be a huge source of Hydrogen. Same with Jupiter.

 

[Venusian Broon]

Hydrogen - just look for water. And you get oxygen...and water as well. Very useful.

Helium three is apparently 'abundant' on the surface of the moon as a result of the solar wind being stopped by the moons surface. I see Wikipedia states however you would have to process 150 million tons of moon regolith to get one ton of Helium three. (although there may be pockets that only require 50 million tons of crunching rock!) Other sources of Helium three - such as on a large gas giant - would obviously require a different approach.

As for mining this stuff...I'm not really an engineer but I suspect that at the temperatures of deep space, you could just mine ice, opencast a bit like they do with ores and coal on earth? As for the helium three, you are trying to unlock the helium trapped in the rock, so possibly just crush it up nice and fine and extract the gases that come out - possibly heating it up as well? There are probably some more ingenuous solutions for both out there, so I bow in reverence to those that suggest them!

 

[Ray McCarthy]

abundance of helium 3 on the surface of the moon

compared to say surface here! There isn't much actually per ton of moon rock. The use for it is theoretical for reactors that don't exist. I don't know how it would be extracted.
Saturn may have much more and be more useful to re-fuel a spacecraft.
The helium sold today is mostly from pre WWII USA reserves. It was by product of oil and gas production and because of the selling of the US reserves no-one is bothering to collect any till that is used up. The Helium 3 isn't needed now, today. Any Helium is fine for Medical & Research cryogenics (cooling to have superconductors) or for balloons. There may be useful superconductors that work at liquid nitrogen temperatures.

Hydrogen is abundant through out the universe.

Plenty of hydrogen here (as water with Oxygen). There is plenty of Hydrogen in Solar system as water, ammonia, hydrocarbons and hydrogen.

The main difficulty is the cost of getting equipment to these places and cost of getting the stuff back. This applies to Asteroid mining. We are not going to run out of anything for many thousands of years (LPG and other hydrocarbons can be synthesised in unlikely event we use up all shale oil and shale gas etc using solar or nuclear plus water and waste carbon*). We can't even guess when it would be more economic to "mine" off world resources, probably never but they could be of use in 100s of years time for spacecraft built or fuelled off world.

[* LPG cars make more sense than hydrogen as it's safer to store, doesn't leak away, tank is lighter, petrol cars can use it and it's cheaper to transport than Electricity** or Hydrogen over long distances, so can be made using solar power in hot clear sky desert areas. Infrastructure to supply it to homes and petrol stations (which already sell it since 1970s in some places) across the world cheaply exists already]

[** LPG cars using internal combustion, fuel cell or turbine are more sensible than pure electric cars as more than 15% is lost in Electricity transmission from Power station***, Lithium battery life can be half existing car warranty life, environmental cost of batteries and 10% lost in charging. Also if electric cars were generally used the Grid would need a x4 upgrade. You'd also have to have swappable battery packs as charge time is too long]

[*** unless Power station is Gas, Solar, Nuclear or Hydro it makes more pollution and CO2 than LPG powered car!]

 

[SilentRoamer]

The main difficulty is the cost of getting equipment to these places and cost of getting the stuff back. This applies to Asteroid mining. We are not going to run out of anything for many thousands of years (LPG and other hydrocarbons can be synthesised in unlikely event we use up all shale oil and shale gas etc using solar or nuclear plus water and waste carbon*). We can't even guess when it would be more economic to "mine" off world resources, probably never but they could be of use in 100s of years time for spacecraft built or fuelled off world.

I agree with this - it's one of the main reasons I mentioned gravity wells. Essentially anything involving planetary mining is going to be very resource inefficient. This drives the cost right up and ultimately mining is about cost - if the mined materials don't cover the cost and there's a net loss then there is no economic viability.

There are plenty of resources on Earth so mining off planet for on planet resource gains seems counter productive. However in the scenario where you are mining things in space to use in space then, you definitely have an advantage. Sure the initial investment is higher (putting mining facilities into space) but then the costs rapidly decrease and the energy requirement becomes much lower. Having mining and manufacturing in space would possibly open other options such Zero-Gee manufacture and medical care. In this case it *could become viable but the stipulations are quite strong.

*Obviously extrapolating costs based on unproven technologies is not something I can do just presenting a possible option.

 

[chrispenycate]

Any helium molecules left in Earth's atmosphere have long since achieved escape velocity and gone off exploring the cosmos. They're barely heavier than hydrogen molecules, after all, and unlike hydrogen, show no tendency to enter into relationships. Any helium left on Earth has originated as alpha particles in the breakdown of radioactive nuclei. Which is why the second lightest element in the universe is found underground.

But solar wind contains a very high percentage of ionised helium (alpha particles again), albeit in wide separation. And there are places where it gets concentrated up ('compressed' would be a little eaggerated for a vacuum you could probably bottle to make electronic tubes/valves out of). Charged fishing nets in the Van Allen belts, compressed and either used in orbit or robotic gliders down to Earth? There should be all the isotopes in the mix.

I'm doing a story where they are collecting solar wind in orbit rather than lifting mass ot of Earth's gravity well for cold gas propulsion, though they have (at present) no intention of isotope separation and use as fusion fuel.