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#1 2014-11-18 11:39:09

Void
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Registered: 2011-12-29
Posts: 3,011

Atmospheric Separations

Atmospheric separations.

A process I think could work on Mars to separate/concentrate components of Martian atmosphere would use water or brine.

http://www.kgs.ku.edu/PRS/publication/2 … P1-05.html

CO2 dissolves with significance in water or brine.

The primary variables affecting the process are temperature, pressure, and salinity.

I seem recall GW Johnson saying that methods to pressurize Martian atmosphere to high pressures  are lacking.

So I propose to pressurize it to a significant attainable pressure, into a cold brine tank where an aerator process might be helpful to promote the dissolution of CO2 into the brine.

This should leave behind a residual gas depleted to a significant degree of CO2, O2, and CO.  It might be possible to make it largely depleted of CO2, leaving behind a concentrate of Argon and Nitrogen, perhaps still containing some CO2.

That mix could go into a greenhouse to clean out the remainder CO2 by plants.  If you wanted to purify it more without plants you could have several stages of brine tanks.

That then leaves brine with lots of CO2 disolved in it, and a small amount of O2 and CO.

It may or may not be possible to extract the O2 and CO with electrical force.  Not water splitting, but "Electroplating"?

The next step would be to pull a partial vacuum on the tank of CO2 and Brine, and Degass the CO2 out, and collect it in some manner desired.  Pressurized gas, Liquid, or Dry Ice.

Note: This process would actually be likely to accumulate a small amount of water from the atmosphere.


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#2 2014-11-20 16:09:56

knightdepaix
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Posts: 225

Re: Atmospheric Separations

Void wrote:

That then leaves brine with lots of CO2 disolved in it, and a small amount of O2 and CO.
It may or may not be possible to extract the O2 and CO with electrical force.  Not water splitting, but "Electroplating"?
The next step would be to pull a partial vacuum on the tank of CO2 and Brine, and Degass the CO2 out, and collect it in some manner desired.  Pressurized gas, Liquid, or Dry Ice.

How about combusting the small amount of CO and O2 to recover some energy for the whole process? In other words, only CO2 and CO or CO2 and O2 would be extracted as end products but not both CO and O2.

Last edited by knightdepaix (2014-11-21 16:53:19)

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#3 2014-11-20 19:08:22

SpaceNut
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Re: Atmospheric Separations

The chamber that the CO2 is placed into needs to be near earth pressure and heated in order to use the water to pull the co2 from the mars air contained in the chamber. This is akin to the CO2 scrubbers for a smoke stack here on Earth. Where by the water is then heated in another chamber to drive up the CO2 pressure and allow for it to be pumped into the holding tanks at high pressure for later use.

Anything else in the initial chamber then captured and stored in a seperate tank for later concentrating.

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#4 2014-11-21 10:55:59

Void
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Re: Atmospheric Separations

Happy to reply to a very nice bunch of contributors.

I would suggest on the limits of my abilities that first the tank be pressurized to the level that practical methods can offer, with Mars atmospheric gasses, and then a spray of atomized water be added to absorbable gasses that can be absorbed into a water liquid.  That then further pressurizing the chamber, and separating the component gasses.

Last edited by Void (2014-11-21 10:59:58)


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#5 2014-11-21 11:12:12

Void
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Re: Atmospheric Separations

knightdepaix

The biggest of all possible wins would be to be able to capture Oxygen and CO, and get more energy from the chemical recombination, than it takes to extract the Oxygen and CO.  I have thought about blood, where it can absorb Oxygen and CO, but of course the CO clogs the method.  It would almost have to be a wet process, which is contrary to the nature of Mars.

I would like to think of dry gills for Mars.  You have hinted that there might be a possibility of getting more out of chemical recombination than it takes to extract.  I don't hold you at risk on this.  To take a chance and sacrifice pride on a hope is not to be held in shame.  We take our pain if we have to.  It is our duty.  But if there was a way to find the mercy that Mars offers, then we should seek it I think.  Could we consider the Martian atmosphere a fluid?   I do think I read that it has conductive characteristics.  What if the (Historical and all inclusive we) could extract coal and Oxygen from the atmosphere of Mars?  If it took less energy to extract then what it could offer, then the humans or whatever that lived there could have a source of energy, and indeed a source of biological activity which would survive dust storms, and winters.

Dry gills on Mars.


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#6 2014-11-21 17:01:16

knightdepaix
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Re: Atmospheric Separations

Void wrote:

knightdepaix [...]
You have hinted that there might be a possibility of getting more out of chemical recombination than it takes to extract.

Assuming the CO2 recovered will be much more than CO and O2 combined for the whole process, the combustion merely recover some energy used for pressurizing the CO2. Maybe I don't fully understand what you meant; I don't think in the first place getting more than extraction

Fishy ?

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#7 2014-11-21 17:40:26

Void
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Re: Atmospheric Separations

Oh, well I was extending.  Supposing it were actually possible to extract Oxygen and CO from a mixture dissolved in a water solution, (Which I am not sure of yet), then we could consider the atmosphere of Mars another solution, with components dissolved into it.

If it were possible to plate naturally produced Oxygen and CO from the atmosphere of Mars using electrical force, then would the chemical recombination of it into CO2 justify the effort?  Fishy's  smile extract their Oxygen from a solution and get by with it.

But intellectually, I belong in the shallow end of the pool on this and my footing may be very uncertain.  Still, I am not afraid to splash around and see if there is a chance of obtaining a power supply from the atmosphere of Mars.  I understand that the content of Oxygen and CO is very very small.  However, as I said, if "Dry Gills" could extract it from the wind blowing over them, then this is something to consider.

I do understand that there is a very good chance the answer is no!, but if it were yes, then Manna from heaven smile

CO2 is to a degree electrically conductive just as impure water is.

Last edited by Void (2014-11-21 17:42:10)


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#8 2014-11-25 09:24:59

Void
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Re: Atmospheric Separations

I was looking for any notions on the web that might support the idea that you could electroplate CO and Oxygen dissolved into the atmosphere onto a Cathode and Anode.

I did not succeed in finding anything so far.

However, Supercritical CO2 is interesting.  A solvent which might allow the extraction of needed materials from the soil.

http://science.nasa.gov/science-news/sc … iticalco2/

So, that could be pretty great, Magnesium as your fuel, and I think you could use CO2 Oxygen substitute?  I'm going to check on that.  It's been around since 2003.

So yes;

http://www.youtube.com/watch?v=2oQ_9nFe9HU

So Dry Ice and Magnesium.  That would indicate to me that spacecraft based on Mars could reasonably carry materials to orbit, to create a thriving orbital industrial culture, once humans were established on Mars.

And interestingly, it appears that this will get you Carbon from the Atmosphere.  Carbon is useful, and further you could superheat it with a solar concentrator, and blow very hot water steam across it to get coal gas, which could be the basis for a hydrocarbon output process.  (Plastics as well).

I still would like to find out if you could electroplate Oxygen and CO from the atmosphere with a dry process.

Last edited by Void (2014-11-25 09:46:07)


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#9 2014-12-03 11:55:49

Void
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Re: Atmospheric Separations

I did not get any answers on the idea of plating anions and cations to two electrodes (+) and (-).  I was hoping someone would straiten me out on that.  Anyway for such a process to work, perhaps UV light would help.

Here are some other processes for separations which are interesting:

http://physics.stackexchange.com/questi … centrifuge

To answer Your question: yes, it is possible to extract nitrogen from the air via a centrifuge, or rather - it is possible to increase the concentration of nitrogen in a gas mixture, there are always going to be some impurities. Whether anybody does it? Probably not, since it's not the most efficient way, as it was noted. In nuclear applications it is used because the requirement is to separate two isotopes of the same chemical element, and since they have exactly the same chemical properties, the only way to separate them is to make use of the mass difference between them. Nitrogen and other air components differ in chemical properties, so probably it's cheaper to use chemical methods here.

Of course I would be expecting the Martian atmosphere to be much better for centrifuging, since CO2 weights quite a lot more than the other gasses in the Martian atmosphere mix it.

That hopefully would leave a mix where all the other component gasses had been enriched, and the CO2 content reduced.

http://en.wikipedia.org/wiki/Artificial_gills_(human)

Another potential source of oxygen generation is plastron respiration.[6] A foam with hydrophobic surfaces immersed in water becomes superhydrophobic, which provides a water-air interface across which oxygen can diffuse into the foam. In nature, this method is used by some aquatic insects (such as water boatman, Notonecta) and spiders (such as Dolomedes triton) to breathe underwater without a gill. This method was experimentally proven by professor Ed Cussler on his dog.[7]

I am interested in this last one both for water.

Also for CO2 as the "Fluid" instead of water (Don't know if an analog process for CO2 as the main fluid component is possible, but it would be good.).

I would be interested if some type of Sponge "Plastron" could be put out in the Martian atmosphere and repel CO2, and CO, but allow other gasses such as Oxygen into it.
Similarly I would like to exclude CO2 and Oxygen and get mainly CO. 
But those are wishes.  I have no idea if it can be done.

Last edited by Void (2014-12-03 12:12:23)


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#10 2014-12-03 13:36:43

Antius
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From: Cumbria, UK
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Re: Atmospheric Separations

I didn't find this thread until I had already posted the 'atmospheric air breathing engine thread'.  I apologise for the duplication.

It would appear that typical Martian temperatures are close to the CO2 triple point.  This means that compressing the CO2 into a liquid can be accomplished with very little compressor work.

Gas separation by centrifuge certainly does work - it is how centrifugal uranium enrichment works.  And in that case, the mass difference between heavy and light uranium hexaflouride is <1% and there is no difference in boiling point or specific density.

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#11 2014-12-03 15:00:42

Void
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Re: Atmospheric Separations

Oh, that's fine.  Your thread is very specific, and this is very general.  Plenty of room I think.

Can you support/refute/don't know, if Oxygen and CO put into a water mixture with significant CO2 and N2 would plate out on two electrodes one (+), one (-).

I am not thinking of electrolysis but rather electroplating.

Last edited by Void (2014-12-03 15:03:33)


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#12 2014-12-03 15:48:09

Antius
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Re: Atmospheric Separations

I am not a chemist, but none of these molecules is ionic.  All bonds are covalent.  The Co2 will form a weak acid in the water (which is ionic) and could presumably be electrolysed.  The CO is mildly polar, but only weakly soluble in water.  The CO, O2 and CO2 would form clathrates, although I do not see how that would be useful for separating them.

The CO and O2 will bond to transition metal surfaces and would require moderate heating for release.  Maybe some sort of noble metal coated power could be used to concentrate the CO/O2?

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#13 2014-12-03 16:09:44

Void
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Re: Atmospheric Separations

Thanks for the help.

I am aware of a process with water in soil which might point a way.  In that case the Germans in WWII used electricity to dry up boggy soil so that they could drive tanks over it.
A negative electrode attracts water in soil.  This I think may be because in a solution, electrons are shared off of the water, and the water molecules themselves then have a positive charge and so flow to the negative electrode.

I would hope to do similar for O2 or CO in a solution of water or CO2, but as you have indicated this may not be realistic. Even if it did work, then does it attract both the O2 and CO molecules to the negative electrode?  Maybe not.

Anyway for an electrode, I might want to try this:
http://en.wikipedia.org/wiki/Artificial_gills_(human)


Another potential source of oxygen generation is plastron respiration.[6] A foam with hydrophobic surfaces immersed in water becomes superhydrophobic, which provides a water-air interface across which oxygen can diffuse into the foam. In nature, this method is used by some aquatic insects (such as water boatman, Notonecta) and spiders (such as Dolomedes triton) to breathe underwater without a gill. This method was experimentally proven by professor Ed Cussler on his dog.[7]

If this does not work, then I have to wonder if you did do electrolysis, that is drive a splitting process where the mix is water, Co2, O2, and CO, what would happen.  Would you get Oxygen and Hydrogen at a discount of electrical force needed?  Or something else.

Finally, I wonder what happens if UV is allowed to shine in the mix and help ionize it?  Might that help?


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#14 2014-12-04 13:52:00

Void
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Re: Atmospheric Separations

I would like to borrow from your work, if my previously suggested water method of separation is inferior in results to it:

From: Index
» Planetary transportation
» New idea for Mechanical CounterPressure suit

http://www.newmars.com/forums/viewtopic.php?id=5856&p=2

Antius wrote:


The Martian atmosphere contains a small percentage of oxygen:

Atmosphere of Mars.
Chemical species    Mole fraction[1]
Carbon dioxide    96.0%
Argon            1.9%
Nitrogen    1.9%
Oxygen    0.145%
Carbon monoxide       0.0557%
http://en.wikipedia.org/wiki/Atmosphere_of_Mars

While this is a low percentage, it's a much higher percentage than that of CO2 in the Earth's atmosphere on which all plant life on Earth is dependent, and therefore on which all animal life is also dependent.

Because of the presence of free O2 in Mars atmosphere, conceivably you could have unlimited spacesuit time on Mars with the oxygen drawn from the surrounding atmosphere. However, the amount of O2 on Mars is so small you would need a fan to draw in more atmosphere. How much air flow would there have to be to get the required amount of breathable oxygen for a person?

  Bob Clark

Going off topic significantly - Martian air appears to contain both a combustible gas (CO) and an oxidiser (O2).  Looking at the phase diagram for CO2 reveals that the triple point is about -58C and 7bar pressure.  This is close to Martian daytime temperatures and significantly above nightime temps.  With this is mind, it should be possible to compress Martian air, remove liquid CO2 and then burn what's left in a gas turbine.  The energy needed to compress the CO2 can mostly be recovered in the expander.

No need for nuclear reactors or solar panels, Mars appears to have its own 'fossil fuel' stored within its atmosphere.

Don't we also need to know the temperatures at which CO and O2 become liquified? They might be mixed in with the liquid CO2 rather than existing as separate gases, though probably as liquids we could still separate all of them by centrifuge.


  Bob Clark

If your separation methods work and the CO2 could be removed, what is left could drive a Chemosynthetic Biosphere.

Then I would attempt to add what would dissolve into cold water into a ice covered reservoir.  I would expect all of the Oxygen and CO to dissolve, and perhaps only some of the Nitrogen and Argon.

Then it is just a matter of finding micro-organisms which can feed off of CO and Oxygen.

Biomass should be produced.  Some heat as well, but I think that will be a small effect.

Interestingly though if this keeps occurring, then the Oxygen content should build up to saturation of the gas in water.  If the CO is digested and not allowed to accumulate, then;

http://en.wikipedia.org/wiki/Artificial_gills_(human)

Artificial Gills, Oxygen from the Martian atmosphere?

What do you think?

Quote:

Like-A-Fish[edit]

Like-A-Fish Technologies, an Israeli business founded by Alan Bodner in 2001, is currently testing an artificial gills prototype.[8] Like-A-Fish's technology uses a centrifuge causing lower pressure at the center, where dissolved air comes out of the water.[9]

As with any artificial gill using dissolved oxygen, air from a huge volume[quantify] of seawater would have to be extracted to provide enough for breathing, requiring large amounts of power for pumping. Therefore, a key issue remaining is battery life. Currently, a 1-kg battery would only last for one hour,[8] whereas a regular scuba tank can last longer (depending on depth). Regular scuba gear is also far simpler, and thus safer, with less to go wrong.

Like-A-Fish currently holds patents in Europe for its system.

Of course there are other methods mentioned in the link.

Last edited by Void (2014-12-04 13:59:53)


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#15 2014-12-04 14:22:55

Void
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Re: Atmospheric Separations


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#16 2014-12-21 20:29:20

SpaceNut
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Posts: 17,747

Re: Atmospheric Separations

Carbon-trapping 'sponges' can cut greenhouse gases

carbon-capture-material-particles-nitrogen-containing-porous-carbon-lg.jpg


The most common carbon capture method today is called amine scrubbing, in which post-combustion, carbon dioxide-containing flue gas passes through liquid vats of amino compounds, or amines, which absorb most of the carbon dioxide.

The researchers have been working on a better, safer carbon-capture method since about 2008, and they have gone through several iterations. Their latest consists of a silica scaffold, the sorbent support, with nanoscale pores for maximum surface area. They dip the scaffold into liquid amine, which soaks into the support like a sponge and partially hardens. The finished product is a stable, dry white powder that captures carbon dioxide even in the presence of moisture.

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#17 2015-08-21 13:15:25

Void
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Registered: 2011-12-29
Posts: 3,011

Re: Atmospheric Separations

Supposed better method to split CO2 into CO & O:
http://phys.org/news/2015-08-porous-mat … oxide.html

Organisms that might eat CO and breath O2:
http://www.popularmechanics.com/space/m … -monoxide/

So I have always wondered about the lack of interest in Chemosynthesis for Mars.
https://en.wikipedia.org/wiki/Chemosynthesis

I don't see it as a complete substitute.  Greenhouses with Photosynthesis are also desired, and also just gardens to amuse humans.

So, as I see it if you have a power grid, and it is large enough to supply the peak power demands, and perhaps have a bit more in case of damage to the system, during off peak times that energy could be used to split CO2.

This would provide you with potential food, and a feedstock for fuels and plastics.

It would also reduce the amount of transparent "Glass" that you would need.  That is always vulnerable and expensive in my opinion, since it generally has to withstand differential pressures of significance, and not leak significantly.  It is also a source of thermal variations.  Heat loss at night, and overheating during the day (Potentially).


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#18 2015-08-21 15:56:01

Void
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Re: Atmospheric Separations

I'm not prepared to vouch for life on Venus (Clouds), but an interesting read.

http://solstation.com/life/ven-life.htm

What I am after is;

(such as hydrogenogens, diverse bacteria and archaea that grow anaerobically utilizing CO as their sole carbon source and water as an electron acceptor to produce carbon dioxide and molecular hydrogen as waste products).

So anaerobic matts where hydrogenogens is present.

http://www.ncbi.nlm.nih.gov/pubmed/22011721

So this is another twist, separate CO and O from CO2 using a process such as in the previous post, and have lower pressure greenhouses with algae matts.  Feed the hudrogenogens water and CO, and it produces Hydrogen for you.

Feed the algae matts to fish as well.  Use some Oxygen to let them breath.


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#19 2015-11-30 20:14:17

Void
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Re: Atmospheric Separations

So, NASA did this apparently, it is similar to what Antius and some others have proposed.  If economical very exciting.

http://ntrs.nasa.gov/search.jsp?R=20040196381

A mechanical process was designed for direct extraction of molecular oxygen from the martian atmosphere based on liquefaction of the majority component, CO2, followed by separation of the lower-boiling components. The atmospheric gases are compressed from about 0.007 bar to 13 bar and then cooled to liquefy most of the CO2. The uncondensed gases are further compressed to 30 bar or more, and then cooled again to recover water as ice and to remove much of the remaining CO2. The final gaseous products consisting mostly of nitrogen, oxygen, and carbon monoxide are liquefied and purified by cryogenic distillation. The liquefied CO2 is expanded back to the low-pressure atmosphere with the addition of heat to recover a majority of the compression energy and to produce the needed mechanical work. Energy for the process is needed primarily as heat to drive the CO2-based expansion power system. When properly configured, the extraction process can be a net producer of electricity. The conceptual design, termed 'MARRS' for Mars Atmosphere Resource Recovery System, was based on the NASA/JSC Mars Reference Mission (MRM) requirement for oxygen. This mission requires both liquid oxygen for propellant, and gaseous oxygen as a component of air for the mission crew. With single redundancy both for propellant and crew air, the oxygen requirement for the MRM is estimated at 5.8 kg/hr. The process thermal power needed is about 120 kW, which can be provided at 300-500 C. A lower-cost nuclear reactor made largely of stainless steel could serve as the heat source. The chief development needed for MARRS is an efficient atmospheric compression technology, all other steps being derived from conventional chemical engineering separations. The conceptual design describes an exceptionally low-mass compression system that can be made from ultra-lightweight and deployable structures. This system adapts to the rapidly changing martian environment to supply the atmospheric resource to MARRS at constant conditions.

So, Antius should like this:
Liquid CO2, then;

Nitrogen, O2, and CO from the atmosphere.

Last edited by Void (2015-11-30 20:16:22)


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#20 2015-12-01 05:58:20

Antius
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From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Atmospheric Separations

Void wrote:

So, NASA did this apparently, it is similar to what Antius and some others have proposed.  If economical very exciting.

http://ntrs.nasa.gov/search.jsp?R=20040196381

A mechanical process was designed for direct extraction of molecular oxygen from the martian atmosphere based on liquefaction of the majority component, CO2, followed by separation of the lower-boiling components. The atmospheric gases are compressed from about 0.007 bar to 13 bar and then cooled to liquefy most of the CO2. The uncondensed gases are further compressed to 30 bar or more, and then cooled again to recover water as ice and to remove much of the remaining CO2. The final gaseous products consisting mostly of nitrogen, oxygen, and carbon monoxide are liquefied and purified by cryogenic distillation. The liquefied CO2 is expanded back to the low-pressure atmosphere with the addition of heat to recover a majority of the compression energy and to produce the needed mechanical work. Energy for the process is needed primarily as heat to drive the CO2-based expansion power system. When properly configured, the extraction process can be a net producer of electricity. The conceptual design, termed 'MARRS' for Mars Atmosphere Resource Recovery System, was based on the NASA/JSC Mars Reference Mission (MRM) requirement for oxygen. This mission requires both liquid oxygen for propellant, and gaseous oxygen as a component of air for the mission crew. With single redundancy both for propellant and crew air, the oxygen requirement for the MRM is estimated at 5.8 kg/hr. The process thermal power needed is about 120 kW, which can be provided at 300-500 C. A lower-cost nuclear reactor made largely of stainless steel could serve as the heat source. The chief development needed for MARRS is an efficient atmospheric compression technology, all other steps being derived from conventional chemical engineering separations. The conceptual design describes an exceptionally low-mass compression system that can be made from ultra-lightweight and deployable structures. This system adapts to the rapidly changing martian environment to supply the atmospheric resource to MARRS at constant conditions.

So, Antius should like this:
Liquid CO2, then;

Nitrogen, O2, and CO from the atmosphere.

A very interesting system.  The abstract does not elaborate as to how the system could be net energy producing.  Are they burning the CO over a catalyst or using a supplental solar energy source to add energy to the CO2?

The condensability of CO2 makes for a very useful energy storage system on Mars.  It suggests that a Martian wind turbine could be an entirely mechanical device, producing liquefied CO2 that can be stored until power is needed.  Solar energy systems could work the same way.  I estimate that 1m3 of liquid CO2 expanded to gas at Martian ambient pressure and temperature 300K would store ~300kWh of energy.  Longer term storage could be accomplished by freezing the CO2 into dry ice and burying it.  This gets around intermittency problems in a way that would not be possible on Earth.

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#21 2015-12-01 09:02:48

Terraformer
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Re: Atmospheric Separations

Net producer of electricity, not net producer of energy. They're talking about using a heat source as part of it. Maybe solar heat could be used?


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#22 2015-12-01 13:55:28

Void
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Re: Atmospheric Separations

You have excellent minds, really, I quack like a duck when I try to get down to some real world situations.  Glad to have your generous collaboration on things that are very hard to make sensible with numbers and logic.  I do try to find where the hopes are, but can quite close the deal on my own.

For me, getting chemical energy from the atmosphere such as CO, might pay for the expense in initial energy, as it might allow us to do chemical manipulations, which of course might be achieved in other ways, but by the time you tally up the whole ledger, perhaps you can afford to play this game.  That is just a hopeful hunch.

Last edited by Void (2015-12-01 13:58:43)


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#24 2017-01-09 19:17:45

Void
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Posts: 3,011

Re: Atmospheric Separations

So, ya, I realize I am behaving in a bit of a manic manner just now.  Was going to back off, but this item is just too important in my opinion.  Must report on it.

http://phys.org/news/2017-01-crystalliz … pture.html

Crystallization method offers new option for carbon capture from ambient air

ORNL's Charles Seipp synthesized a simple compound known as guanidine that was found to bind strongly with carbon dioxide directly from the air and form insoluble carbonate crystals that are easily separated from water. Credit: Oak Ridge National Laboratory/Genevieve Martin

"Through our process, we were able to release the bound carbon dioxide by heating the crystals at 80-120 degrees Celsius, which is relatively mild when compared with current methods," Custelcean said. After heating, the crystals reverted to the original guanidine material. The recovered compound was recycled through three consecutive carbon capture and release cycles.

Guanidine:
https://en.wikipedia.org/wiki/Guanidine

Guanidine is the compound with the formula HNC(NH
2)2. It is a colourless solid that dissolves in polar solvents. It is a strong base that is used in the production of plastics and explosives. It is found in urine as a normal product of protein metabolism. Guanidine is the functional group on the side chain of arginine.

So it is speculated on the above text that CO2 can be separated from the other gasses of the Martian atmosphere by this process, leaving a residual.

It is not certain that the trace O2 and CO will not also be absorbed by the Guanidine.  I certainly don't know.

But even if you get "Tailings" of a N2 & Argon mix, it would still be useful.

Further the purified CO2 output might be more easily compressed to 5.5 bar and rendered as liquid CO2.

It sounds like a potentially useful industrial manipulation of Martian atmosphere.

If it only took the CO2 and left a "Tailings" of N2, Argon, O2, and CO, etc. then that could be put into a fermenter where micro-organisms would digest the CO and 1/2 of the O2, leaving a mix of N2, Argon, and O2(Trace).

That then could be liquefied and centrifuged to yield N2, Argon, and O2?  Maybe.

If somehow we would be that lucky, it would be literally bread from heaven.  (Photolysis), with a pinch of Oxygen to boot.

Of course if the O2 and CO/H2/CH4 were boosted by an artificial photolysis using metal oxides and a focus from heliostats, the effect might be much larger.  But natural photolysis actually makes the whole planet Mars a giant solar collector.

Hmm... Wasn't even thinking about the value this could be to maintaining an internal atmosphere in a spacecraft or habitat.  Maybe it's good for that also.

Last edited by Void (2017-01-09 19:39:45)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#25 2017-01-09 21:25:09

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 17,747

Re: Atmospheric Separations

It seems like we are using the martian chemistry to make this happen with the help of some clever baterial useage.

Martian surface chemistry...
https://upload.wikimedia.org/wikipedia/ … 4-crop.png

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