Dehydrated Water?

[Asperion]

Here is a strange concept that recently came up. As humans move into space everything that we that take with us must be reduce to its smallest state, including air and water. We have already gotten a start in this department by dehydrating most of our food and even going beyond food into other things this still holds true. We are even continuing the trend by eliminating paper (at least there are those who would like to) and putting anything currently on paper onto electronic form. However, if we could remove most of the mass of water, then imagine what that would do to the travel off-planet (or in general). Lets hear any thoughts about what you may think about how this would impact any part of society, not just travel.

[Hyper-Man]

Re: Dehydrated Water?

 

NASA already does this. It's called a Hydrogen Fuel Cell.

 

Proton exchange membrane fuel cells

 

In the archetypical hydrogen–oxygen proton exchange membrane fuel cell[10] (PEMFC) design, a proton-conducting polymer membrane, (the electrolyte), separates the anode and cathode sides. This was called a "solid polymer electrolyte fuel cell" (SPEFC) in the early 1970s, before the proton exchange mechanism was well-understood. (Notice that "polymer electrolyte membrane" and "proton exchange mechanism" result in the same acronym.)

 

On the anode side, hydrogen diffuses to the anode catalyst where it later dissociates into protons and electrons. These protons often react with oxidants causing them to become what is commonly referred to as multi-facilitated proton membranes. The protons are conducted through the membrane to the cathode, but the electrons are forced to travel in an external circuit (supplying power) because the membrane is electrically insulating. On the cathode catalyst, oxygen molecules react with the electrons (which have traveled through the external circuit) and protons to form water — in this example, the only waste product, either liquid or vapor.

[Xavier Onassiss]

Re: Dehydrated Water?

 

Here is a strange concept that recently came up. As humans move into space everything that we that take with us must be reduce to its smallest state' date=' including air and water. We have already gotten a start in this department by dehydrating most of our food and even going beyond food into other things this still holds true. We are even continuing the trend by eliminating paper (at least there are those who would like to) and putting anything currently on paper onto electronic form. However, if we could remove most of the mass of water, then imagine what that would do to the travel off-planet (or in general). Lets hear any thoughts about what you may think about how this would impact any part of society, not just travel.[/quote']

 

...why, do you realize that 70% of you is water? And as human beings, you and I need fresh, pure water to replenish our precious bodily fluids.

- General Ripper (Dr. Strangelove, 1964)

 

Eliminating most of the water mass would drastically cut the requirements for crewed spacecraft, in terms of both crew mass and consumables. This would make them a bit easier to design, in terms of weight, especially for long-duration missions.

 

It would also give rise to endless conspiracy theories about how "The Process" used to reduce the mass of water in the human body was, in fact, a communist/socialist/alien/terrorist/facist/capitalist/corporatist/freemason/illuminati/boy scouts plot to sap and impurify all of our precious bodily fluids.

[Folded]

Re: Dehydrated Water?

 

Okay, I have to get pedantic here. A molecule of water consists of two atoms of Hydrogen and one of Oxygen. This cannot be changed, altered or reduced. Even if you're carrying the Hydrogen and Oxygen separately, their combined mass does not change relative to the amount of water you can make out of them. If the trip requires one hundred thousand kilograms of water, then you have to carry that total amount of mass in Hydrogen and Oxygen.

 

The way to reduce the mass associated with water is to recycle it. This is the focus that NASA and other agencies worldwide have been working on, to improve the filtering and recycling of water in the systems on board a ship to reduce the overall mass that needs to be carried. Steel can be replaced with aluminum or carbon compounds to reduce mass. There is nothing you can do to reduce the mass of a molecule of water without invoking a general ability to reduce the mass of an atom or molecule (which we can't do, yet).

[Lucius]

Re: Dehydrated Water?

 

Okay, I have to get pedantic here. A molecule of water consists of two atoms of Hydrogen and one of Oxygen. This cannot be changed, altered or reduced. Even if you're carrying the Hydrogen and Oxygen separately, their combined mass does not change relative to the amount of water you can make out of them. If the trip requires one hundred thousand kilograms of water, then you have to carry that total amount of mass in Hydrogen and Oxygen.

 

The way to reduce the mass associated with water is to recycle it. This is the focus that NASA and other agencies worldwide have been working on, to improve the filtering and recycling of water in the systems on board a ship to reduce the overall mass that needs to be carried. Steel can be replaced with aluminum or carbon compounds to reduce mass. There is nothing you can do to reduce the mass of a molecule of water without invoking a general ability to reduce the mass of an atom or molecule (which we can't do, yet).

 

Mass aside, can the bulk be reduced?

 

Gas, unlike liquid, is compressible.

 

Lucius Alexander

 

Dehydrated palindromdary

[Lord Liaden]

Re: Dehydrated Water?

 

Another possibility is to harvest water as needed during one's trip through space. There are many sources of water-ice in our solar system: comets, asteroids, moons, planets. Permanent "rehydrating" stations could eventually be set up on some of the larger bodies.

[Folded]

Re: Dehydrated Water?

 

Another possibility is to harvest water as needed during one's trip through space. There are many sources of water-ice in our solar system: comets' date=' asteroids, moons, planets. Permanent "rehydrating" stations could eventually be set up on some of the larger bodies.[/quote']

 

That is, in fact, the plan. One of the exciting things to come out in the last decade or so is that there is water ice on the Moon. That changes the profile for an interplanetary journey enormously. Not having to lift all those kilos of water out of Earth's gravity well is a big savings in fuel and expense, and makes a permanent Lunar base a real possibility.

 

To answer Lucius' question, I don't think you can compress water vapor into a smaller volume than the same mass of liquid water. But bulk is just an engineering issue, mass is one of economics. More mass equals more fuel, more bulk doesn't usually increase your fuel consumption (at least not significantly).

[Lucius]

Re: Dehydrated Water?

 

That is, in fact, the plan. One of the exciting things to come out in the last decade or so is that there is water ice on the Moon. That changes the profile for an interplanetary journey enormously. Not having to lift all those kilos of water out of Earth's gravity well is a big savings in fuel and expense, and makes a permanent Lunar base a real possibility.

 

To answer Lucius' question, I don't think you can compress water vapor into a smaller volume than the same mass of liquid water. But bulk is just an engineering issue, mass is one of economics. More mass equals more fuel, more bulk doesn't usually increase your fuel consumption (at least not significantly).

 

I was not talking about vapor, but refering to this post

 

NASA already does this. It's called a Hydrogen Fuel Cell.

 

In which Hyper Man describes taking hydrogen and oxygen as fuel for a hydrogen fuel cell that produces water as a "waste" product.

 

Lucius Alexander

 

Ask a palindromedary

[Hyper-Man]

Re: Dehydrated Water?

 

That is, in fact, the plan. One of the exciting things to come out in the last decade or so is that there is water ice on the Moon. That changes the profile for an interplanetary journey enormously. Not having to lift all those kilos of water out of Earth's gravity well is a big savings in fuel and expense, and makes a permanent Lunar base a real possibility.

 

To answer Lucius' question, I don't think you can compress water vapor into a smaller volume than the same mass of liquid water. But bulk is just an engineering issue, mass is one of economics. More mass equals more fuel, more bulk doesn't usually increase your fuel consumption (at least not significantly).

 

Water/Ice on the Moon is exciting and certainly would make setting up a lower gravity well refueling station there a more economical way to explore the rest of the solar system since we could drink it or apply electricity via solar cells and make Oxygen to breath and Hydrogen to combine with it for rocket fuel.

 

However, the far more valuable resource (if ever found) would be significant deposits of Helium 3 due to its extremely higher potential efficiencies in nuclear fusion (and the fact that it throws off charged Protons instead of Neutrons).

It is literally one of the few resources that would make economic sense to go to the Moon and bring back to earth.

 

Some fusion processes produce highly energetic neutrons which render reactor components radioactive with activation products through the continuous bombardment of the reactor's components with emitted neutrons. Because of this bombardment and irradiation, power generation must occur indirectly through thermal means, as in a fission reactor. However, the appeal of helium-3 fusion stems from the aneutronic nature of its reaction products. Helium-3 itself is non-radioactive. The lone high-energy by-product, the proton, can be contained using electric and magnetic fields. The momentum energy of this proton (created in the fusion process) will interact with the containing electromagnetic field, resulting in direct net electricity generation.[16]

[Folded]

Re: Dehydrated Water?

 

I was not talking about vapor, but refering to this post

 

 

 

In which Hyper Man describes taking hydrogen and oxygen as fuel for a hydrogen fuel cell that produces water as a "waste" product.

 

Lucius Alexander

 

Ask a palindromedary

 

Ah, I was looking at the "Gas can be compressed" comment you had made. Using fuel cells to generate water and power at the same time is part of extending the water cycle on long voyages, and a very important one. Any consumable you can get to do two or more jobs at once is a good thing. So yes, Hyper Man is absolutely correct, and I suspect he knows a lot more about this stuff than I do (fuel cells, at least).

[McCoy]

Re: Dehydrated Water?

 

I was not talking about vapor, but refering to this post

 

 

 

In which Hyper Man describes taking hydrogen and oxygen as fuel for a hydrogen fuel cell that produces water as a "waste" product.

 

Lucius Alexander

 

Ask a palindromedary

This is in response to many post, most of which were referenced leading to yours.

 

Recycling gets the mass to a minimum.

 

The mass required is the mass required.

 

"Packing," on the other hand, getting the water (hydrogen hydroxide) into the smallest volume, Probably at this point in time the most efficent system is taking liquid hydrogen and oxygen. Let me run some numbers and get back to you.

 

That was the plot point that had me throwing things at the screen during the original "V" mini-series, the aliens had traveled intersteller distances to steal from Earth -- the most abundant substance in the universe. Guess that solves the Fermi paradox, no inteligent life out there.

[Folded]

Re: Dehydrated Water?

 

Both HyperMan and McCoy have it right. There are ways you can reduce the amount of water you need to bring along, but once you have that number figured out, that's the mass. Now, figure out a way to reduce the amount of water a human needs in order to survive, and you've really got something.

[Christopher]

Re: Dehydrated Water?

 

Okay' date=' I have to get pedantic here. A molecule of water consists of two atoms of Hydrogen and one of Oxygen. This cannot be changed, altered or reduced. Even if you're carrying the Hydrogen and Oxygen separately, their combined mass does not change relative to the amount of water you can make out of them.[/quote']

Actually, they get heavier when carried separate:

http://en.wikipedia.org/wiki/Binding_energy#Mass_defect

But apparently what we save in volume/energy production and thus mass is much more than what it costs to carry them seperate.

 

Aside from seperating it, I heard about using alternative forms of Ice, that are way denser than the common "Freezer Ice":

http://en.wikipedia.org/wiki/Very_high_density_amorphous_ice#Very-high-density_amorphous_ice

[Cancer]

Re: Dehydrated Water?

 

Water has a complicated equation of state, but if you want to store it as that high density amorphous ice, you need to maintain it at that low temperature (not hard) and high pressure (that's a trick). That 1 to 2 GPa mentioned there is 10,000 to 20,000 times atmospheric pressure, and unless you have force field technology, there is no way to maintain that pressure without a rather massive, immensely strong, pressure vessel. In that article you cite, it mentions a density of 1.26 g/cm^3, which is only a 26% gain over liquid water at 1 atmosphere and 4 Celsius. More effort that it's worth to do that aboard a spacecraft.

[McCoy]

Re: Dehydrated Water?

 

Both HyperMan and McCoy have it right. There are ways you can reduce the amount of water you need to bring along' date=' but once you have that number figured out, that's the mass. Now, figure out a way to reduce the amount of water a human needs in order to survive, and you've really got something.[/quote']

All depends on how efficent you can get your recycling. Which may have psychological effects as well as engineering limits. I feel reasonably safe in assuming every atom of oxygen in the atmosphere has been through at least one kidney since the kidney evolved, so we evolved drinking and breathing recycled pee, but for some people, even trained scientists, there's an "ick" factor when it becomes too obvious it's their own recycled pee.

 

I may have spoken too quickly before. Can someone check my math on this? Barring exotic isotopes for a moment, by weight water is 16/18th's or roughly 89%, oxygen, which means the remaining 2/18ths, ~11%, is hydrogen. The density of liquid oxygen is 1.14, so to yield a gallon of liquid water we would need (1*.89/1.14), or about 0.78 gallons of LOX, correct so far? Now we need enough liquid hydrogen to react with that, so we need um, just over 416 grams of liquid hydrogen, so at a density of 0.07 grams/cc that's 5.94 liters or -- over a gallon and a half? You have to react over two gallons of liquid hydrogen and oxygen to get one gallon of liquid water?

 

Did I get the math wrong or is liquid water actually the most space-efficent storage?

[Folded]

Re: Dehydrated Water?

 

All depends on how efficent you can get your recycling. Which may have psychological effects as well as engineering limits. I feel reasonably safe in assuming every atom of oxygen in the atmosphere has been through at least one kidney since the kidney evolved, so we evolved drinking and breathing recycled pee, but for some people, even trained scientists, there's an "ick" factor when it becomes too obvious it's their own recycled pee.

 

I may have spoken too quickly before. Can someone check my math on this? Barring exotic isotopes for a moment, by weight water is 16/18th's or roughly 89%, oxygen, which means the remaining 2/18ths, ~11%, is hydrogen. The density of liquid oxygen is 1.14, so to yield a gallon of liquid water we would need (1*.89/1.14), or about 0.78 gallons of LOX, correct so far? Now we need enough liquid hydrogen to react with that, so we need um, just over 416 grams of liquid hydrogen, so at a density of 0.07 grams/cc that's 5.94 liters or -- over a gallon and a half? You have to react over two gallons of liquid hydrogen and oxygen to get one gallon of liquid water?

 

Did I get the math wrong or is liquid water actually the most space-efficent storage?

 

I have absolutely no clue. Chemistry math was always one of my (many) weak points. I do physics better. However, I believe that LOX is actually liquid O2. It would mean that every molecule of LOX would contribute to two molecules of H2O, though I don't think that that changes your equations at all.

[McCoy]

Re: Dehydrated Water?

 

I have absolutely no clue. Chemistry math was always one of my (many) weak points. I do physics better. However' date=' I believe that LOX is actually liquid O2. It would mean that every molecule of LOX would contribute to two molecules of H2O, though I don't think that that changes your equations at all.[/quote']

Hydrogen and oxygen are both diatomic, liquid hydrogen and oxygen are H2 and O2. Two molicules of H2 reacts with one molicule of O2 to produce two molicules of water. Which doesn't affect my calculations. Water has a molecular weight of 18, oxygen an atomic weight of16, and hydrogen 1, so 16/18 of the mass of water is oxygen. The thing I didn't know that threw a monkey wrench into the works (and I checked several sources) was that liquid hydrogen only weighed 7% as much as the same volume of water.

 

Shades of flubber, now I'm wondering what a hypothetical lighter than air liquid would be like? Probably rapidly dissipating, among other things.

[Cancer]

Re: Dehydrated Water?

 

Shades of flubber' date=' now I'm wondering what a hypothetical lighter than air liquid would be like? Probably rapidly dissipating, among other things.[/quote']

 

It would taste like the bends.

[Old Man]

Re: Dehydrated Water?

 

Liquid water is the densest practical state. The amorphous solid might be denser but as cited above, the pressure requirements negate the marginal benefit. You can't compress a gas to a point where it is denser than the liquid state.

 

There really isn't much point to maximizing the density of the water anyway. Once you're in space, there's virtually no benefit to minimizing the overall volume of your craft. It might help you get it off the ground and through the atmosphere, but even then liquid water is going to be the best you can do.

[Christopher]

Re: Dehydrated Water?

 

Just for Fun, because it fit's the Threads Name:

http://www.youtube.com/watch?v=WpQej7M_HXw

[matthewcelis]

Re: Dehydrated Water?

 

Okay, I have to get pedantic here. A molecule of water consists of two atoms of Hydrogen and one of Oxygen. This cannot be changed, altered or reduced. Even if you're carrying the Hydrogen and Oxygen separately, their combined mass does not change relative to the amount of water you can make out of them. If the trip requires one hundred thousand kilograms of water, then you have to carry that total amount of mass in Hydrogen and Oxygen.

 

The way to reduce the mass associated with water is to recycle it. This is the focus that NASA and other agencies worldwide have been working on, to improve the filtering and recycling of water in the systems on board a ship to reduce the overall mass that needs to be carried. Steel can be replaced with aluminum or carbon compounds to reduce mass. There is nothing you can do to reduce the mass of a molecule of water without invoking a general ability to reduce the mass of an atom or molecule (which we can't do, yet).

 

Rave on, John Donne. Tell it like it is.

[Folded]

Re: Dehydrated Water?

 

Rave on' date=' John Donne. Tell it like it is.[/quote']

 

Um, thanks?

[Christopher]

Re: Dehydrated Water?

 

Did I get the math wrong or is liquid water actually the most space-efficent storage?

I think there is one big saving when usign Fuel cells: You need fewer reactors/solar panels/batteries. You get your drinking water and energy for mixing it.

 

Also, could we actually make the mass of water (or whatever else heavy we have) by storing it using this physical effect:

http://www.herogames.com/forums/showthread.php/87382-Quantum-Flux-Tube-model-railroad-with-superconductors!

 

I know the main issues is getting us a superconductor with suiteable operating temperature. But otherwise, could this help?

[Old Man]

Re: Dehydrated Water?

 

I'm not seeing how magnetic flux pinning could reduce mass.

[Christopher]

Re: Dehydrated Water?

 

I'm not seeing how magnetic flux pinning could reduce mass.

As far as I see it, the pinning is completely negating gravity/mass. Without any outside force directly working agaisnt gravity. It just makes the Mass a Non-Issue.

 

So, when I put a permanent magnet at the bottom of my spaceship and "pinned" my cargo in the magnetic field right over it - would the ship have to move

[Own Mass] + [Magnet Mass] + [Cargo Mass]

or

[Own Mass] + [Magnet Mass]

since the mass is "just pinned" there, and thus not impending the movement of the ship.