Gas giant mining

[abomination]

It strikes me that most large ships (the space going equivalents of container ships, super tankers & especially Queen Mary sized liners) won't waste time visiting the local gas giant to scoop & refuel. On top of that the local hi tech world will have many uses for fusion power aside from space travel. Therefore a plentiful supply of hydrogen needs to be obtained.

Therefore I'm currently working up plans for an orbital gas mining rig, and would welcome your thoughts & input.

Basically we're talking about a platform with a pump sucking up a very long straw (8000km or so) feeding through the mother of all purifiers into a large detachable tank.

This really shouldn't be beyond 3I capabilities; after all we were laying 3000km undersea cables in the 1860s.

I've settled on a 200000 kilolitre hull with a 75x75m maximum floor plan and about 5 decks high. As this is the standard size for my modular cargo ships. A standard fuel tank is a sphere just under 75m diameter, and everything else follows this size.

The ships themselves are essentially a ladder with accommodation & control at one end & a huge engine at the back. The fuel / cargo units are slotted in the gaps between the rungs. The largest of these ships may have as many as twenty modules.

The Platform would be accompanied by some sort of rack to keep the spare fuel tanks in. And a tug to move them between the rig and the storage facility, as well as to occasionally reposition the rig as its orbit decays due to atmospheric drag on the straw.

Periodically a tanker will arrive from the main world to swap empty tanks for full ones or just pump fuel from one to the other. (I haven't done a risk assessment)

 

[hdan]

What a great idea! TONS of potential for adventure, with hastily contracted supply runs, emergencies, terrorist/hostage situations, etc. If the fuel rig is far enough from the main world, it's possible that transit to/from is not as safe as one might like.

Some random thoughts:

Any world with Starport B+ seems likely to have some sort of orbital refueling station, and a Gas Mining Rig like you describe might a great place to get that fuel.

Ships (especially military ships) might go directly to the rig to refuel, and maybe save a little money in the process. The advantage over skimming (which would probably be illegal in a system with fuel rigs) would be that the fuel was already refined, and refueling might take less time that actually diving in to skim for yourself, provided that access to the rig was easy.

I don't know if a surface-synchronous orbit "beanpole" tube or a continuously grav-lifter suspended station (or maybe even a huge surface area "floating" station that rides the dense lower atmosphere?) would be best.

There isn't really a "surface" on a gas giant of course, so you'd be matching up with the equatorial wind speed. The advantages of being in a high orbit like this would be that the fuel barges wouldn't need to be streamlined to retrieve fuel.

A "floating city" (either grav or lighter-than-atmo) would have an easier time collecting the gas since it wouldn't need as long a hose, but fuel barges and customers would have more difficulty accessing the rig.

Another option for a system without easily accessible gas giants is to tow a comet into a Lagrangian point between the star and main world, and build an "ice cracking station" there. The same type of fuel barges would be useful, and could return oxygen as well as hydrogen, maybe processing the collected water on the way back to the high port. I suppose such a place wouldn't really need an operator on-location, especially if the fuel barges just collected ice, but having a small station opens up more adventuring possibilities, so there should at least be a "scraper station" that pre-packs the ice for transit, and naturally a small craft of some sort that keeps it supplied.

 

[Dragoner]

I don't know if I have written about this someplace else here, IMTU I have a company called Fuel Star that maintains refueling stations at gas giants, in empty hexes for transportation points, even near worlds so one doesn't have to go to the starport to refuel. The dropping a hose into the Gas Giant is a good idea, I hadn't thought of that.

 

[Xerxeskingofking]

It strikes me that most large ships (the space going equivalents of container ships, super tankers & especially Queen Mary sized liners) won't waste time visiting the local gas giant to scoop & refuel. On top of that the local hi tech world will have many uses for fusion power aside from space travel. Therefore a plentiful supply of hydrogen needs to be obtained.

Therefore I'm currently working up plans for an orbital gas mining rig, and would welcome your thoughts & input.

Basically we're talking about a platform with a pump sucking up a very long straw (8000km or so) feeding through the mother of all purifiers into a large detachable tank.

This really shouldn't be beyond 3I capabilities; after all we were laying 3000km undersea cables in the 1860s.

I've settled on a 200000 kilolitre hull with a 75x75m maximum floor plan and about 5 decks high. As this is the standard size for my modular cargo ships. A standard fuel tank is a sphere just under 75m diameter, and everything else follows this size.

The ships themselves are essentially a ladder with accommodation & control at one end & a huge engine at the back. The fuel / cargo units are slotted in the gaps between the rungs. The largest of these ships may have as many as twenty modules.

The Platform would be accompanied by some sort of rack to keep the spare fuel tanks in. And a tug to move them between the rig and the storage facility, as well as to occasionally reposition the rig as its orbit decays due to atmospheric drag on the straw.

Periodically a tanker will arrive from the main world to swap empty tanks for full ones or just pump fuel from one to the other. (I haven't done a risk assessment)

classic gas giant fuel skiming is done by a hypersonic pass though the upper atmosphere to ram feed low pressure gasses into the fliters (or rather, the tanks, to be run though the fliters later). I can think of a few problems iwth you idea, plus a few suggestions:

1) the "rig" would need to be sat on a 1-3G drive or simmilar to compensate for the GG large gravity ("surface" gravity for a Jupiter sized GG is 2.5g, the other 3 giants in our solar system are 1.14-0.8 G.)

2) it would be easier to make a longer, geostationary rig, either housed in a astroid at geostationary height, or with a counterweight that far out and the rig proper lower down (to reduce the power needed for pumping (since every meter you lift it is a meter you need to activly pump it). having it move relitive to the GG would add massive extra wind strains on the feed pipe the pipe is gonna be under massive strain anyway, and likey made out of some form of Bonded Superdense or other super material.

3) current science thinking is that, after a certian depth, the pressure and tempature reach levels where hydrogen changes into a "metallic" liquid. this is much closer to the surface that previously thought (for Jupiter, we think it's about 12,000 km below the "surface", or about 25% of it's radius in form the surface). It may, using advanced traveller tech, be able to push a pipe down thier (that pipe would be need to be longer than the diamiter of the earth, but hey, its sci-fi, and that's an engineering problem).

Now, if you keep the pressure inside the pipe low (comparred to an outside pressure of over a million atomspheres), you could get a serious decompression rush of metallic hydrogen reverting back into normal hydrogen. play it right, you might be able to get the pressure release to do all the hard work for you, In other words, you'd get a nice, old school oil plume, with the hyrdogen speeding past the rig stand, which, using mocleuar scale fliters, siphons off the non-h2 gases and vent them safely (or some them for sale later as a bi-product, if their is a demand for them).

one advantage of this would be that the pipe would have, for all intents, an unlimited supply of MH to draw on, and the high pressures at the pipe head would be effectivly grounded solidly, meaning that the pipe is unlikey to "wander" dispite high winds in the middle atmosphere.

in all likeyhood, you going to be getting H2 out of my MH rig much faster than you can process it, or even box it, so a lot of the plume is gonna have to be vented and left to fall as ice crystals. the only real limit is how wide you can make the pipe, and by extension how many tons of unrefined fuel you can capture in a day.

for arguements sake, say 1 ton of refineable fuel a second. thats 60 tons a minute, 3,600 tons a hour, and 86,400 tons of fuel every day. assuming 20 tons a day per ton of processor (how MgT plays it) you'd need about 4,320 to processor to keep up with that demand.


you know what? screw the tankers, freeze the H2 into a 90,000 ton asteriod of pure h2. stick a solar shade between it and the sun, and it should be alright (space is about 3K without solar heating, and h2 is solid up to about 14K), strap a drive on it, point it at the mainworld and send it on it;s way. park it in orbit around the planet, and a then lob off H2 as required, thaw, and bingo! you have fuel!



....


I'm sorry, i let my imaginaton run away with me for a while thier......

 

[fusor]

Presumably you're using magical antigrav tech to pump up tons of gas up an 8000km pipe, without having to work against the GG's strong gravitational field?

I think a skyhook-type structure might work better to be honest.

 

[abomination]

Sorry maths fail. There should be 11 & a bit decks in a standard cargo holder.

@ Xerxes, some nice ideas.

I think the height of the rig will be a compromise between being geostationary and having a really long pipe or lower down where you'll have to deal with greater drag.

Might it be possible to orbit at the same average speed of weather systems.

I like the idea of the flying hydrogen lolly. I have to admit one of the reasons for the tankers is that traveller gives you rules to build 1,000,000 ton ships so I wanted to build one. Although this is just the sort of ship you need for supplying deep space / trans rift dumps.

I thought about adding a manouver drive, but I figured the tug would be enough to keep it from splashing down. Mostly I had in mind something unable to move under it's own power like a north sea oil rig.

 

[Xerxeskingofking]

Presumably you're using magical antigrav tech to pump up tons of gas up an 8000km pipe, without having to work against the GG's strong gravitational field?

I think a skyhook-type structure might work better to be honest.

hey, we're already assuming a magically strong pipe longer than the width of the earth (on the order of 12,000-15,000 km, for a jupiter sized GG), able to withstand pressures of a million atmospheres. adding gravitc plates to the inside of the pipes to push the H2 up isn't that much more of a strech, especially since grav plates are already a commonplace tech in Traveller.

the idea was to use a expansion of the hydrogen into a lower pressure area (inside the pipe) to push as far as possible. i;d aggree that getting 12,000Km isn't really lilkey, but i havn't done the maths, and it sounds cool.

I like the idea of the flying hydrogen lolly. I have to admit one of the reasons for the tankers is that traveller gives you rules to build 1,000,000 ton ships so I wanted to build one. Although this is just the sort of ship you need for supplying deep space / trans rift dumps.

make it. I'll run up a 1G, J0 gigaton design for MgT, moving fuel form the GG to the mainworld (doesn't need to be fast).

also, think Depot systems. a Tigeress class superBB takes 174,000tons of fuel. even a million ton supertanker couldn't move enough for a whole Batron. you'd need several running form the GG to their parking orbits.

 

[hdan]

Sorry maths fail. There should be 11 & a bit decks in a standard cargo holder.

@ Xerxes, some nice ideas.

I think the height of the rig will be a compromise between being geostationary and having a really long pipe or lower down where you'll have to deal with greater drag.

Might it be possible to orbit at the same average speed of weather systems.

I like the idea of the flying hydrogen lolly. I have to admit one of the reasons for the tankers is that traveller gives you rules to build 1,000,000 ton ships so I wanted to build one. Although this is just the sort of ship you need for supplying deep space / trans rift dumps.

I thought about adding a manouver drive, but I figured the tug would be enough to keep it from splashing down. Mostly I had in mind something unable to move under it's own power like a north sea oil rig.

You can get pretty crazy with high-tech (but semi-realistic) physics if you're willing to push things a bit:

Obviously, the "Straw" won't "suck itself" (so to speak), so you'd need some sort of magnetic tube and a way to ionize the gas you want to lift. (LOLs - turn the H2 into plasma at the base, use magnetic tubes to lift it, then refrigerate it back at the top, capturing the heat to power your grav lifter plates!)

Plus if your hose is conductive, it might generate electricity for you as it passes through the planet's magnetic field. (Or you could use the hose for propulsion through the opposite effect - push electricity through it and use the planet as a giant electric motor to keep you in orbit.)

If you're lifting plasma and you decide that the heat+pressure of the plasma is enough to lift it, then the plasma itself could generate the EMF you need to keep your station in orbit, but your hands might get tired from all the waving you'd have to do.

I can imagine the engineers stationed on such a rig would have their hands full maintaining the plasma ducts, monitoring the magnetic flux lines and navigating the storm winds for optimal positioning. Decent computers would be essential, as would talented and experienced personnel.

Plus the vision of approaching a city-sized artificial platform floating in the thin upper atmosphere of a gas giant, covered in spherical tanks and humming/pulsing machinery with a giant plasma bearing "stem" below (crackling with spin-off lightning) and occasional plasma flares above as the refinery cooks off impurities is an awesome one.

I sure hope that the lower platform doesn't disturb some previously unknown native wildlife, or that the planet's storms are shifting too rapidly to get the platform out of the way....

 

[Xerxeskingofking]

You can get pretty crazy with high-tech (but semi-realistic) physics if you're willing to push things a bit:

Obviously, the "Straw" won't "suck itself" (so to speak), so you'd need some sort of magnetic tube and a way to ionize the gas you want to lift. (LOLs - turn the H2 into plasma at the base, use magnetic tubes to lift it, then refrigerate it back at the top, capturing the heat to power your grav lifter plates!)

Plus if your hose is conductive, it might generate electricity for you as it passes through the planet's magnetic field. (Or you could use the hose for propulsion through the opposite effect - push electricity through it and use the planet as a giant electric motor to keep you in orbit.)

If you're lifting plasma and you decide that the heat+pressure of the plasma is enough to lift it, then the plasma itself could generate the EMF you need to keep your station in orbit, but your hands might get tired from all the waving you'd have to do.

I can imagine the engineers stationed on such a rig would have their hands full maintaining the plasma ducts, monitoring the magnetic flux lines and navigating the storm winds for optimal positioning. Decent computers would be essential, as would talented and experienced personnel.

Plus the vision of approaching a city-sized artificial platform floating in the thin upper atmosphere of a gas giant, covered in spherical tanks and humming/pulsing machinery with a giant plasma bearing "stem" below (crackling with spin-off lightning) and occasional plasma flares above as the refinery cooks off impurities is an awesome one.

I sure hope that the lower platform doesn't disturb some previously unknown native wildlife, or that the planet's storms are shifting too rapidly to get the platform out of the way....

I just realised this is starting to turn into bespin........

 

[hdan]

A quick follow up on the "straw sucking itself" - the gas at lower altitudes isn't going to just shoot up the pipe because one end is in a lower pressure area - the reason the gas is down there is because of gravity, not the weight of the gas above it.

Otherwise, gas would ALWAYS spew away from a planet, since the entire outer atmosphere is lower pressure than the inner atmosphere.

 

[hdan]

I just realised this is starting to turn into bespin........

LOL! I guess that is the prototypical gas mining operation. I wasn't picturing anything quite that habitable or well appointed. Sort of more like the Nostromo in appearance.

 

[fusor]

hey, we're already assuming a magically strong pipe longer than the width of the earth (on the order of 12,000-15,000 km, for a jupiter sized GG), able to withstand pressures of a million atmospheres. adding gravitc plates to the inside of the pipes to push the H2 up isn't that much more of a strech, especially since grav plates are already a commonplace tech in Traveller.

the idea was to use a expansion of the hydrogen into a lower pressure area (inside the pipe) to push as far as possible. i;d aggree that getting 12,000Km isn't really lilkey, but i havn't done the maths, and it sounds cool.

You don't need any of that at all though. There's plenty of hydrogen in the uppermost part of the atmosphere where the pressure is about 1 earth atm. You could just have a station sitting there sucking up/processing the hydrogen/helium "air" around it. There's way more gas in the planet than anyone could possibly use after all, it's not going to run out or anything.

Heck, have many similar stations scattered around the planet. You won't need any high pressure protection or ridicutech "pipes" (why have a pipe anyway? You'd just be limiting the amount of stuff you can process to what fits in the pipe, rather than use the stuff that's all around you).

Have the station in the atmosphere of a smaller gas giant where the gravity at the cloudtops is more like 1G and you won't even need grav plates (for human comfort anyway. You'll still need them to allow the station to hover, unless you want to use warmed up hydrogen balloons to use as buoyancy).

 

[aramis]

the idea was to use a expansion of the hydrogen into a lower pressure area (inside the pipe) to push as far as possible. i;d aggree that getting 12,000Km isn't really lilkey, but i havn't done the maths, and it sounds cool.

Unless you use gravitics or lots of boost fans, won't happen, as the gravity of the planet is what holds it there in the first place.

make it. I'll run up a 1G, J0 gigaton design for MgT, moving fuel form the GG to the mainworld (doesn't need to be fast).

also, think Depot systems. a Tigeress class superBB takes 174,000tons of fuel. even a million ton supertanker couldn't move enough for a whole Batron. you'd need several running form the GG to their parking orbits.

It needs 2G or more simply to survive the GG...

 

[Rigel Stardin]

Here is my thoughts.

I've already thought about it and the slang term I use for these stations is a Syphon. It's basically a small station (5-100 personal) depending on the size. It either runs refueling shuttles or a hydrogen scoop with refining equipment on a tether (Cable or remote controlled).

Now the tether idea would work in my eyes because it doesn't need to go very deep into the atmosphere because all it has to do is run the same ranges as a Gs 1 ship during a refuelling pass. We all assume that an aerobraking manuver by a starships is all that is required to gather fuel during a refuelling pass. You could simply park the tether at or near the altitude where the maxium effectives for refueling takes place.

Since Traveller has really never discuss the effective range of a hyd-scoop, it is also possible that the scoop could be placed even further out and just suck the hydrogen out of the atmosphere without even entering it?

Another location for such a station would be in close orbit around a star...

 

[abomination]

I think the challenges of sucking up metallic hydrogen deep within a GG would out weigh the benefits of doing so. It's just so much easier to harvest hydrogen in the upper atmosphere where fuel skimming happens, why would you bother?

The idea was to have constant supply of commercial amounts of fuel at a safe altitude. Rather than relying on huge armoured skimming vessels with the crews on danger money.

Atmospheric refineries, while very stylish would still need to get the fuel up the gravity well. But would represent the kind of inattention to H&S that Gerry Anderson used to set up Thunderbirds plots.

The only item at risk would be the straw. Clearly this would have to be streamlined in some way. And the end would need to be steerable & therefore probably powered.

 

[Xerxeskingofking]

I think the challenges of sucking up metallic hydrogen deep within a GG would out weigh the benefits of doing so. It's just so much easier to harvest hydrogen in the upper atmosphere where fuel skimming happens, why would you bother?
.

Rule of Cool.

The idea was to have constant supply of commercial amounts of fuel at a safe altitude. Rather than relying on huge armoured skimming vessels with the crews on danger money.

Atmospheric refineries, while very stylish would still need to get the fuel up the gravity well. But would represent the kind of inattention to H&S that Gerry Anderson used to set up Thunderbirds plots.

The only item at risk would be the straw. Clearly this would have to be streamlined in some way. And the end would need to be steerable & therefore probably powered

A mid atomsphere refineary, processing H2, to be loaded onto mid sized tankers to be brought up to a high orbit storage rig for transfer to a supertanker for transport whereever would be more feasible than the "straw" design, and certianly within the bounds of traveller tech.


Maybe use something like the modular cutters, where you can just swap out a full tank for a empty one and dive back down to fill it. build the tanks for quick change over, you could move quite a few in a day.

I think that we want the stoage area to be well out, at say a GG-moon L point, to keep the supertankers and non gas minering craft out of the way.

It needs 2G or more simply to survive the GG...

depends, like i said, Saturn, Uranus and Neptune all have "surface" gravities of about 1G (1.14-0.8 G). The latter two aren't really suitable for skimming (thier a different composition to juptier and saturn), but Saturn could be skimmed by a 1G ship with a only a slight overclock of the engine.

Unless you use gravitics or lots of boost fans, won't happen, as the gravity of the planet is what holds it there in the first place.

true, but you can get oil to run straight up a pipe due to pressure on earth, and even to use pressure to do almost all the work, so it is possible to use pressure to help you move fluid agianst gravity.

 

[HG_B]

true, but you can get oil to run straight up a pipe due to pressure on earth, and even to use pressure to do almost all the work, so it is possible to use pressure to help you move fluid agianst gravity.

The oil moves because it is inside a "sealed" container under pressure. Not the case for a gas giant. You can't drop a hose from orbit into a planet's atmosphere and "suck" it up into space. Think of how a glass tube barometer works.

 

[fusor]

Rule of Cool.

Cool != Practical

Nobody would even think about investing in a platform consisting of a thousands of km long pipe that sucked up hydrogen from deeper in the atmosphere. It'd be like proposing a solar power station in a sun-baked desert that got its sunlight entirely through a 1ft-square window.

 

[Rigel Stardin]

Does the hose have to be the size of an oil drigging rig Pipe? Couldn't it be smaller?
There was also the suggestion of turning the hydrogen into plasma?
Why not use the vacum of space to pull up the hydrogen through the pipe to the tanks?

There is also a secondary issue concerning the use of Syphons:

The first being a planetary government/corporation control of the Gas Gaint and using it for economical reasons. By controling this natural resource it also controls ship traffic in their system.

Military use: Instead of ships having to 'dive' for their fuel, syphons provide a quick way to refuel ships and get them back into combat.

Syphons may also foster interstellar trade because they reduce wear and tear on the ships using them as long as the fuel cost stay reasonable.

 

[hdan]

Does the hose have to be the size of an oil drigging rig Pipe? Couldn't it be smaller?

The bigger the hose, the more gas it can move.

There was also the suggestion of turning the hydrogen into plasma?
Why not use the vacum of space to pull up the hydrogen through the pipe...

I suggested plasma, since you could use magnetic fields in the tubes to "pump" it up. But mostly because I thought a giant pulsing tube of plasma would look cool, and the whole gas mine idea has "Rule of Cool" written all over it.

You can't actually use the vacuum of space to pull up the hydrogen because things don't work that way. I'll explain:

The reason a straw works is because when you reduce the pressure in the straw, the atmospheric pressure on the top of your drink pushes the drink into the straw. If you sealed your cup and had only the straw coming out, you couldn't suck up any liquid. (Unless your glass was flexible, like when you use those little milk cartons and close the top on your straw, or when you suck on a water bottle that doesn't have a good enough vent - when you suck in, the sides of the container collapse.) Likewise, if you were in a vacuum, you couldn't drink an unsealed container with a straw, though you could squeeze the container, effectively providing your pressure through mechanical means instead of gas pressure.

Another way to think about it - if a tube in space could suck away a small amount of atmosphere, then a really big tube could suck away a whole lot of atmosphere. What if the tube were as big as the whole planet? Since we still have an atmosphere, empirically the vacuum of space won't suck away an atmosphere.