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#1 2012-01-07 01:49:29

JoshNH4H
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Carbon and Carbon Monoxide

We say it so much that it has practically become a mantra.  "Mars has Carbon!  Mars has Carbon!"  But this isn't true; or at least, it's not entirely true.  Mars certainly has prodigious amounts of the element Carbon, fairly accessibly in the atmosphere and as ice at the poles, somewhat less accessibly as carbonate minerals locked up in the regolith.  However, it does not have elemental Carbon just lying around, not in significant quantities.  There is some Carbon Monoxide in the atmosphere, at a concentration of 0.07%, a partial pressure of .005 mb.  This is essentially not obtainable, especially when one considers how similar most of the properties of CO are to N2 and O2, which are both found in greater quantities in the martian atmosphere.

My question:  What is the best way to produce Carbon and Carbon monoxide, both of which will be necessary for a wide variety of industrial processes* in a Martian colony?

Now, there is no question that it can be done.  An inefficient way to do so would be to electrolyze water, and then use the hydrogen to react with the CO2 to produce Carbon Monoxide, or with more H2 and at potentially higher temperatures, Carbon.  It is also possible to make Carbon monoxide disproportionate into Carbon dioxide and carbon, with the right catalysts.  This is a Boudouard Reaction.

My problem with this:  Efficiency.  It would be necessary to split one mole of water molecules to get one mole of carbon monoxide, and two moles of water molecules to get two moles of carbon.  The energy required for these reactions (CO2->CO+1/2 O2 and CO2->C+O2), at 100% efficiency is 283 kJ/mol and 393.5 kJ/mol, respectively.  The minimum input you would need if you're using a hydrogen intermediate is 286 kJ/mol and 572 kJ/mol respectively.  Electrolysis machines will be less than 100% efficient; We're probably looking at more like 75% or perhaps somewhat less.

So if you want to make Carbon monoxide and then disproportionate when you need Carbon (if you can get that to work; I would think it would coat your catalyst pretty easily, unless you could find a solvent which will get the carbon soot off.  To my knowledge there is not anything known in which carbon is appreciably soluble), you've got a fairly efficient reaction.  On the other hand, if you can't get this to work you're taking a significant efficiency hit.  I heard about Carbon Dioxide electrolysis a couple years ago, though I don't know any specifics.  Anyone know anything about the process?

*Off the top of my head, Carbon or CO for smelting, C for alloying with Fe to make steel, CO for reaction with Hydrogen to produce Formaldehyde (for polymers) and methanol, CO for the production of Carbonyl Iron, which will probably be the method of choice for purifying and concentrating Iron, graphite for electrolysis electrodes, graphite for indoor lubricant (it doesn't work outside, on Mars, though) and indubitably a bunch of other things which did not occur to me at the moment.


-Josh

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#2 2012-01-07 21:16:33

SpaceNut
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Re: Carbon and Carbon Monoxide

The capture of CO2 is one that is also used in the sabatier reactor for another form of making water with hydrogen. There is also the fischer process.. so on and so depending on the catylist in the reaction chamber..I think that the CO2 is first pressurized to cause it to be liquified and then electrolysis is used to free up the Oxygen molecule such that when mixed with hydrogen generates water with a waste gas of CO which is a shame to release when as uyou meantion it is ideal for iron smelting....

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#3 2012-01-08 15:13:17

GW Johnson
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Re: Carbon and Carbon Monoxide

At 2-6 mbar pressures,  it is energetically very,  very unfavorable to utilize the Martian atmosphere as a source of CO2 carbon,  although it certainly CAN be done.  Compressing gas from low density to high density is very,  very,  very,  very energetically inefficient,  and we are talking final processing pressures here measured in tens of atmospheres,  or tens of thousands of mbar.  That is one whale of a compression ratio.  We've never built machines like that before.  The ones here going from 1 atm to 10's of atm are AT MOST 70% efficient.  Efficiency decreases SHARPLY as required pressure ratio rises. 

Sources of solid-CO2 dry ice near or at the poles would be a whole lot easier to utilize:  you just mine it.  You do have to be careful of sublimation in uncovered deposits,  that's all.  Once indoors and warmed up,  it's a gas at atmospheres to tens of atmospheres.  Very little inefficient gas compression is required,  IF you plan your process correctly.  This sort of thing WILL NOT be possible at all the interesting landing sites,  only those at or near the poles,  where the dry ice is hidden amongst the water ice (the OTHER very thing we are looking for). 

This is exactly what I keep writing about.  No two sites are alike in resources.  The point of "exploration" is to go and find out for sure (1) what all is there,  and (2) where exactly is it?  This is to support any possible future activities utilizing those very same ill-distributed resources.  What if there once was life on Mars?  There might be coal,  oil,  and gas deposits.  Who knows?  Nobody,  yet!

It would be just about as easy and expensive to tote all your propellants for the first mission(s) from Earth,  as it would be to try to make carbon-based chemical propellants (methane,  etc) in-situ from such a thin atmosphere,  local ice deposits notwithstanding.  That's because of the 10^4 compression ratios required.  Ridiculous prospect,  technologically. 

Now,  hydrogen and oxygen from water only,  that's a different picture.  Ease and feasibility depends on ice deposit THICKNESS and PURITY.  If favorable,  then how easy and efficient that process might be!  Even if restricted to solar PV efficiencies under 10%.  You do not learn about thickness and purity from orbit,  or by scratching the surface 10 cm deep. 

GW

Last edited by GW Johnson (2012-01-08 15:16:50)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#4 2012-01-08 18:01:15

JoshNH4H
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Re: Carbon and Carbon Monoxide

GW-  I'm not talking about a mission.  I'm talking about a colony.  The colony absolutely needs to get these elements, and since it will certainly be equatorial it will not be able to go to the poles and get them.

That said, there has got to be a way of getting the CO2 in the martian atmosphere up to 1 bar and above; it is simply inconceivable that there wouldn't be.  Further, it is my understanding that the primary loss in terms of pressurizing a gas is in the form of heat.  On frigid Mars, heat is only lost energy if one does not use it properly.  The excess heat from compressing that gas can be used to melt water or to heat buildings or make a chemical reaction go.  Intelligent design of the ventilation system in a Mars colony can potentially keep it at a nice temperature without any additional energy expenditure.  This is one venture in which the laws of thermodynamics are potentially on our side.  That's good engineering and efficient living. 

Further, even if compression fails (which I doubt that it will), it's always possible to simply have a freezer and freeze the CO2 ourselves. 

Spacenut, I assume you were referencing the Fischer-Tropsh process, which can be used to produce heavier hydrocarbons from CO and H2?  I was not aware of this process previously, but it solves a very important problem that the colony will have, namely where it will get its hydrocarbons from.  It's probably not going to use them in the same way we do on Earth (For example, vehicle fuel where such is needed will probably be methanol and NO2), but they will still definitely find uses within the colony. 

I guess my primary question is if CO2 electrolysis machines are as simple to build as water electrolysis machines, which can easily be built at home, albeit probably not very efficiently.  If it is as simple as liquifying Carbon dioxide, adding an ionic or acidic solute, and creating a voltage difference between two electrodes, and then collecting the gases produced that would certainly be worth it.  That would have the additional benefit of releasing the Nitrogen, Argon, Oxygen, and Carbon monoxide in the atmosphere (In order to make this safe for breathing, it would probably be necessary to heat this mix to a fairly high temperature in order to get the Oxygen to react with the Carbon monoxide, which at that concentration would certainly be toxic.  I suppose one could alternatively cool it down first to 86 K, which will liquify the Argon and Oxygen but not the CO or the N2, and then further cool it down until the CO condenses out, and finally, once that has been removed, collect the nitrogen.  I'm not sure which will be less resource and labor intensive.  I would guess heating it to combustion, for the simple reason that you can use thermal and not electrical energy for that.


-Josh

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#5 2012-01-08 20:09:00

SpaceNut
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Re: Carbon and Carbon Monoxide

That is correct advance CRS for me but in either case have a look at The Mars Homestead: a Mars Base Constructed from Local Materials
http://www.spacearchitect.org/pubs/AIAA-2006-7472.pdf

http://www.marshome.org/files2/MarsHome … sPlant.ppt

http://www.authorstream.com/Presentatio … owerpoint/

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#6 2012-02-07 22:24:02

GW Johnson
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Re: Carbon and Carbon Monoxide

If you are building colonies,  build more than one.  I'd put them in the northern lowlands,  which were once ocean beds.  There will be whopping amounts of water ice buried deep.  That's ice mining.  Put one colony much nearer the north pole for dry-ice mining,  and build a railroad between them.  Use local ice/basalt fiber/local rock aggregate to form the concrete track for the rail line.  Use rubber tires on the train cars.  If you can ensure by careful design that the tracks never see much bending or tension,  then plain ice-aggregate unreinforced "concrete" will do.  (Basalt fiber manufacture is likely to be rather energy-intensive,  unless you can find a local active volcano with a basaltic type of lava,  not the silicic type.) 

To quickly and easily get CO2 gas at 1-10 atm,  haul in mined dry ice by rail to your processing plant,  and put it in a pressurizable space of limited volume,  then apply solar heat,  and vaporize the dry ice.  It will pressurize the closed space quite easily,  no machinery required!  Use that pressure to transport the gas down a pipe to where you do whatever you want to do with it. 

If you just want raw solid carbon,  I've heard tell that Phobos is a carbonaceous chondrite.  There's a carbon mine.  But you do have to fly it down to the surface to use it. 

It's some kind of iron ore,  plus a massive energy source,  that will be needed longer-term.  I'm thinking steel-making,  which is extremely energy-intensive.  But steel is the key to the future of any viable technologically-based society.  Steel and concrete.  We've already seen it here.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#7 2012-02-08 09:26:59

Rune
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Re: Carbon and Carbon Monoxide

Errr... you know, if energy is too expensive to make a metal-making infrastructure stick, we might as well pack up and go home. But (there's always a but):

You can import that energy! A few kilograms of highly enriched Uranium would keep a megawatt-sized (or gigawatt, if built locally, it's the optimum size on Earth) power plant running for a VERY long time. If you need carbon and your options are to build two bases far away from each other so one can supply CO2 ice to the ore-producing one, then you are way better off just building more powerplants, importing high-density nuclear fuel, and accepting a high(er) energy price for you steel and aluminum, and pay it by not having to import two whole bases and a transportation system to go from one to the other. Talking about importing steel or any construction material from earth when they can be made using energy is nuts, IMO. Energy, using nuclear systems, can be packaged so densely that it makes importing any other thing, even rare platinum-group metal to use as catalysts, a waste of payload mass by comparison.

Plus, all of a reactor main components can be built locally if you have a healthy heavy metal-making industry, so you have potential for expansion and truly big, 1GW commercial powerplants with decades of life. Imagine the kind of industry those powerplants could sustain. And the reactors can keep it running almost no matter the final energy price of the metal. The only problem would be how to get Mars unhooked from the expensive nuclear fuel from Earth. One solution is for someone to make fusion work economically, but I won't hold my breath for that one. Even if I have some short of hope for polywell still. Plenty of Deuterium on all ice, I'm sure.

IMO, the energy price is a nice consideration to have in mind, because the less energy that has to be imported, the tighter your energy budget is, the better in general. But if you have to pay the mass bill somewhere, if you are going to add significant complexity or a big number of processes/specialized machinery to save a few kilowatts, then think twice, since energy is one of the few thing that could be imported from Earth "economically".


Rune. Of course, it would be nice if the energy budget of local solar power turned out positive, manufacturing and maintenance energy costs included. I won't hold my breath on that either.


In the beginning the universe was created. This has made a lot of people very angry and been widely regarded as a "bad move"

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#8 2012-02-08 18:50:20

JoshNH4H
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Re: Carbon and Carbon Monoxide

On power generation:

While I've been stressing the minimizing of power, I don't think that there will be an actual shortage of electrical (or thermal) energy, or that the costs of using that energy will be prohibitive.  Though what record there is (seeing as this is a point which imo has not been touched upon much) will probably find me arguing for the relative scarcity of power and energy, this is most likely due to the fact that much of the record is me in conversation with louis who, be he right or be he wrong, is usually more optimistic than I am.

Anyway, a couple of things to consider with imported energy in the form of enriched Uranium, in what I feel to be the order of their importance:

1) Imported Uranium does not implicitly represent free energy any more than sunlight does.  Now, obviously there are potential benefits to nuclear power compared to solar. But just because you imported a few kilos of fissile Uranium does not mean that you can just plug your colony right into the metal and get limitless energy.  I'm not accusing you of suggesting that, but it is very important to keep in mind what would actually be different between Nuclear and Solar power for an early colony. 

So we ask ourselves: What would be different?  The technological limitations for an early colony mean that going from heat energy to electrical energy will be by pretty standard means regardless of what is actually creating the heat.  I know nuclear is at least has the potential to be a higher grade heat source than concentrated solar power, and this might lead to savings in terms of turning the energy from heat into electricity, but it also might not.  It's also possible that the materials available to the colony will lend themselves best to the relatively lower temperatures of a concentrated solar power unit.  I can't say. 

Power in a CSP plant is generated using parabolic trough mirrors.  In a nuclear reactor, it's generated using a small but complex core region.  The reactor core will probably be cheaper than the large number of mirrors, but once again I cannot say by how much.

2) Radiation.  While many of the people here will probably agree with me that modern fears of radiation are excessive and mostly unnecessary, this is a complicating factor in the construction of nuclear power plants.  The radiation in the nuclear power plant serves to limit the service life of the core region and makes it impossible to do real service work on it because it has a tendency to become radioactive. 

3) Energy independence and safety. Earth is a long way away, and if for whatever reason the ships get grounded, the colony is screwed.  There's also the possibility that Earth will become resistant to sending over fissile uranium, and in that case the colony will be SOL.  Breeder reactors do not get around this because the reserves of Thorium and Uranium are probably not accessible to an early colony. 

Now, there is one incredible benefit to nuclear power that might make all of this worth it: 24.6/7.  If you have a constellation of a few nuclear power plants providing energy for your colony, you will have electrical energy or high-quality heat energy literally all the time.  With solar, you can get power for 8, maybe 10 hours of the day.  This makes the idea of having two shifts per day and halving the amount of equipment needed moot.  It also necessitates the colony investing in extensive energy storage schemes in case of dust storms.  With nuclear, you bypass all of that quite nicely and the colony becomes almost entirely independent of the external situation.

For an early colony, I don't think it's worth it.  On the other hand, when we get to the point where we can comfortable refine thorium, Mars will likely convert to nuclear power in very short order.


-Josh

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#9 2012-02-08 21:33:37

SpaceNut
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Re: Carbon and Carbon Monoxide

http://www.marsdrive.com/forums.aspx?g=posts&t=309

There was some descusion about Thorium reators on the MarsDrive site but the actual core of any of the reators need a working medium to capture the heat in and to allow for its transfer to the electrical creation unit. This was in the Habitation of Mars in Salt Domes with the intention of moderate terraforming topic....

http://www.marsdrive.com/forums.aspx?g=posts&t=293

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#10 2012-02-08 23:57:11

JoshNH4H
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Re: Carbon and Carbon Monoxide

Spacenut- I note that the first link suggested that the efficiency of their proposed splitter was still just 1%.  15% was "possible," but that is a far-future kind of thing.  Meanwhile, even if Cerium is the most common of the rare earth elements, it is still pretty uncommon and -more importantly in my understanding- it does not tend to be concentrated by geological processes.

The second link seemed somewhat dubious.  After all, the average thorium concentration on Mars is significantly lower than it is on Earth.  I don't doubt that it is the kind of thing that is possible in the long run, but in the short run of an early colony I don't think we'll be looking at extracting thorium too start up a local nuclear industry quite yet.  Long term is is absolutely something that the colony should look at and I think that after maybe 20-25 years martian settlements will all be nuclear powered, using some kind of Molten Salt Reactor.


-Josh

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#11 2012-02-10 14:54:04

GW Johnson
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Re: Carbon and Carbon Monoxide

I don't know a lot about the details of nuclear reactors,  but I have heard of the U-233/Thorium-232 breeder cycle.  The Indians are actually trying to do this.  You have to use a normal enriched-uranium reactor (involves U-235 fission and the inevitable U-238 breeding to Pu-239) with Th-232 also inserted,  to be bred into U-233.  You do this until you accumulate enough U-233 to shut down the uranium plant and just go with a straight U-233 reactor,  breeding its own fuel from Th-232.  This may take a small number of years (I dunno exactly).  The waste products of U-233/Th-232 are much more benign than the U-235/238-Pu-239 cycle. 

I kinda think that's something we ought to bootstrap into operation down here right now,  and just ship U-233 product to space settlements,  for direct breeding of local thorium into U-233 fuel.  It saves having to ship two breeder reactors,  if we could just get it started here first.  Thorium is a lot more plentiful here on Earth than uranium,  and I rather suspect that's true elsewhere,  too. 

Also,  a U-233 reactor could also be a nuclear rocket.  Even in open-cycle gas core designs,  the radioactive plume is a lot less objectionable than a uranium or mixed-oxide reactor basis. 

Just a thought. 

There's a a natural timing here.  If we could get the technology started now,  it would be ready as we plant settlements soon,  and they need atomic power for whatever the local industries might prove to be,  not long after. 

After all,  you simply cannot make steel powered by solar energy.   

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#12 2012-02-10 20:46:19

JoshNH4H
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Re: Carbon and Carbon Monoxide

GW, yeah, that's the fuel cycle I was talking about with the Thorium reserves on Mars.  Reactor cores will use a lot of Uranium, though.  An early colony (~500 people) is not going to want to either pay for importing it or for develop all the infrastructure required to get that uranium when the infrastructure required to build solar collectors is very simple and, just as importantly, not all that different from the infrastructure that will be used to build basically everything else that will be used by the colony.  This website suggests that costs on Earth could be as low as $.07/kWh (Average US energy price $.0983/kWh.  I trust the government to give existing costs, but not so much to project them.  Elsewhere I have seen quoted prices be somewhat higher, but the basic point here is that it is possible to generate a fair amount of energy at relatively reasonable cost using CSP.  Keeping in mind that it is a simpler technology than Nuclear power, I think that its relative cost will be lower because the Martian economy, by and large, will not be fitted out to do that kind of high-tech work.

More directly:  The statement that "you simply cannot make steel with solar energy" is categorically false.  You, of all people, know that nothing is impossible.  We will have electricity (The solar energy will be focused with mirrors and then transported to a Brayton turbine, where it will be turned into rotational and then electrical energy).  This electrical energy can then be used to electrolyze water to Hydrogen and oxygen, which then smelts with the Iron just like we do on Earth- just a bit simpler, seeing as we don't have to first react coke with oxygen to get CO gas.

The question is cost.  I think that this will not be prohibitively expensive in terms of energy.  It is my understanding that this kind of design, on Earth, gets about 15% efficiency.  That's not too bad.  With the exception of dust storms, Mars tends to be a fair bit clearer than Earth, so you don't lose as much sunlight as you would suspect.  We're also going to be on the equator or right near it, so the sunlight will probably be somewhat more than [Intensity near whoever reads my post]*[Relative clarity of Martian Atmosphere]*[Relative levels of sunlight at Mars orbit].

It's definitely possible, I think.  Might not be easy, but what is?


-Josh

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#13 2012-02-11 09:48:34

GW Johnson
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Re: Carbon and Carbon Monoxide

The electric furnaces they use for steel-making are using scrap steel as an input.  That just a remelting thing. 

Making steel directly from pig iron and coke is an enormously power-hungry combustion-driven process.  There is a hollow furnace stack fed compressed air and fuel at the bottom,  which burn to create heat at the bottom,  percolating up through the stack with lots more air injection.  There are alternating layers of pig iron,  coke,  and limestone filling the stack.  The coke and the added air burn,  the 3000+F temperature melts the pig iron and the limestone,  and the molten limestone is a liquid slag coating the puddles of iron so that it does not oxidize. 

That's the slow,  relatively "energy-efficient" way  (LOL).  For the fast,  not-so-efficient way,  look at a Bessemer converter.  It's really quite spectacular when they turn on the oxygen lance to burn out the excess carbon.  Those processes don't sound very amenable to solar PV to me.  It'd be hard to make that kind of chemistry happen at 1200 MWe direct from a nuclear plant here on earth. 

What's needed on Mars is a different set of chemistries reflecting the availability of atmospheric CO2 instead of O2.  No one knows what that is yet.  Maybe we'll be lucky and the yet-to-be-defined process won't be such an energy hog.  I wouldn't hold my breath about that,  though. 

Do we yet know if Mars has both uranium and thorium reserves in deposits accessible on the surface?  If there are deposits like that,  the entire thorium breeder cycle could be bootstrapped into operation locally with HEU as the starter.  The machinery to refine the materials would either have to be imported or built from parts and supplies locally.  The smarts to do it is intellectual property shipped electronically from earth.  The whole thing is dependent upon supplies of alloy steels locally. 

Sort of a chicken-and-egg thing.  Those situations always require a kick-start of some kind. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#14 2012-02-11 18:31:24

JoshNH4H
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Re: Carbon and Carbon Monoxide

Important points:

1. First of all, I am not talking about generating power using Solar Photovoltaic Panels.  I'm talking about using Concentrated Solar Power (CSP).  These are two entirely different systems.  The latter is a lot more like the way we generate energy in our power plants now, the only difference is that the source of the heat is not coal or natural gas or oil or a nuclear reactor core but sunlight that has been focused using a parabolic mirror onto a target.  Wikipedia has a pretty decent article on Concentrated Solar Power, if you want to read up a little more on it.  It's an interesting technology, and it definitely has applications both on and off Earth.

2. I am aware of the fact that Iron production on Mars will not be as cheap as it is on Earth (however you would actually do that calculation; If you really think about it it'll be harder than you would think seeing as there will be very little currency exchange and the exchange rate in this case need not necessarily be closely tied to the actual Purchasing Power Parity (PPP) rate, which will actually vary between industries), it will certainly not be impossible.  Production of Iron on Mars will be somewhat more analogous to the production of Aluminium on Earth, in that it will require the input of electrical energy (albeit indirectly).  In an ironic turn of events, if my preferred production method for Aluminium [I'm in the process of writing a post right now] involves mostly, but not exclusively, thermal input.  In any case, there's nothing impossible about electrolyzing water to get hydrogen, and then heating the hydrogen with Iron ore in a solar furnace.  It takes a minimum of 237 kJ/mol to electrolyze water at STP, so that's 711 kJ of electrical energy/2 mol of Iron, plus the energy required to heat the mixture.  I think we can expect efficiencies around 70%- right in line with what we see on Earth.  Source.  The reaction would start occurring at 812 K (539 C) based on calculation of delta G, but I think we would be looking at somewhat higher temperatures in reality, probably right about on par with blast furnaces. 

For a mental comparison: Think of it as being something like the production of Aluminium here on Earth.  Energy intensive but not prohibitively so.  If CSP can supply energy for the colony (which it can), then there is no reason to believe that production of Iron will be prohibitively energy intensive.

3. I don't know about Uranium on Mars, but results have been released for thorium.  The Gamma Ray Spectrometer aboard Mars Odyssey provided some nice results for a number of different elements.  Thorium Concentration:

Th_040305_NG_5x5_SmB10_016_EQ75_with2Logos_web.jpg

Average concentration of Thorium in crustal material on Earth is 12 ppm, according to Wikipedia.  This indicates that Mars has a comparatively small amount of thorium relative to Earth.  This doesn't mean that there won't be ores to be found but it does mean that they will be harder to find and that there won't be as much of them.  Or at least that's my interpretation; I am not a geologist and if someone has good reason to believe otherwise based on the specifics of the evolution of the planet Mars then I am more than willing to admit that I am just guessing.

In other words, I don't think that scouting around for the indubitably rare reserves of thorium is going to be worth it.


-Josh

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#15 2012-02-12 10:03:13

SpaceNut
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Re: Carbon and Carbon Monoxide

The last posts of GW Johnson and JoshNH4H triggered another topic to come to mind over on Marsdrive..

The post can be found in Void's postHere ignore the title...

The desire is for high heat, and a mix of water vapor and Carbon Dioxide Vapors:
Here is a reference, refering to a method of producing a high heat, which can generate Hydrogen and I presume under some circumstances Methane.

http://en.wikipedia.org/wiki/Solar_furnace

It actually is not the reference I would prefer, but it may help. The refrence I prefer involves a solar concentrating mirror with a quartz window where focused light enters a chamber through a quartz window, and Carbon Dioxide and Water Vapor are introduced, and the great heat produces some hydrocarbons, if a catalyst is provided.

However, I am looking for a remote method of terraforming Mars.
I suggest instead, Hydrogen Bombs introduced to a polar ice cap, not to melt them directly, but to act upon Carbon Dioxide (From the atmosphere or the ice cap), and water vapor primarly from the ice cap. The introduction of a catalyst is optional and hopefully will not be necessary.

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#16 2012-02-12 19:51:03

SpaceNut
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Re: Carbon and Carbon Monoxide

Here is another thread http://energyfromthorium.com/forum/view … 04d9838f1f where sanman has been posting.....

Also the start up for the Thorium reactor just might come from the very rover that is one its way to Mars as we speak...MSL.Curiosity..IIRC it has a RTG power source...plutonium-238

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#17 2012-02-13 16:38:57

JoshNH4H
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Re: Carbon and Carbon Monoxide

Spacenut- A solar furnace is definitely a good way to get up to high temperatures using solar energy directly.  I would imagine that in nearly every instance on a Martian colony where heating is necessary, using concentrated sunlight will probably be the go-to method, unless it's impractical for some reason.  Seeing as we're going to be using solar thermal power for a while, it's simply the most efficient.

Unfortunately, the Plutonium-238 used in RTGs cannot be used as fissile material.  I believe it is only Pu-239 and PU-241 which are fissile.  RTGs are based on normal radioactive decay, instead of fission chain reactions, unfortunately.  That said, I would imagine that what the colony initially imports from Earth will be nuclear powered and therefore there would be fissionables on-planet.  The issue would be more with dealing with them without causing nuclear disasters.


-Josh

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#18 2012-02-23 21:07:28

sanman
Member
Registered: 2012-02-23
Posts: 27

Re: Carbon and Carbon Monoxide

SpaceNut wrote:

Here is another thread http://energyfromthorium.com/forum/view … 04d9838f1f where sanman has been posting.....

Also the start up for the Thorium reactor just might come from the very rover that is one its way to Mars as we speak...MSL.Curiosity..IIRC it has a RTG power source...plutonium-238

Hi guys,

I was looking for some of my old posts on this forum, and I can't seem to find them. I know I had more than a few posts on here, but it's as if they've all been erased. I feel like a Stranger in a Strange Land. I'm scared.

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#19 2012-02-24 02:12:31

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,024
Website

Re: Carbon and Carbon Monoxide

If you have something from which to build the mirrors,  a solar concentrating furnace makes a lot of sense for melting things.   I know the ones here are made using mirrors of silvered glass,  and with a big-enough field of actively-steered mirrors,  can melt steel. 

Where do we get silvered glass,  or an effective substitute,  on Mars?  Where do we get the materials from which to fabricate mirror towers than can be steered?  Where do we get the electronic/electric controls?  We're talking substantial-horsepower electric motors here,  and gears to boot. 

Looks to me like,  initially at least,  a lot of this gear has to come from Earth.  Chicken-and-egg problem. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#20 2012-02-24 12:59:46

Rune
Member
From: Madrid, Spain
Registered: 2008-05-22
Posts: 191

Re: Carbon and Carbon Monoxide

sanman wrote:

Hi guys,

I was looking for some of my old posts on this forum, and I can't seem to find them. I know I had more than a few posts on here, but it's as if they've all been erased. I feel like a Stranger in a Strange Land. I'm scared.

Well, everything post-2008 got lost in... how are we calling it? The great crash of '11? Whatever you call it, you are in the same situation as all of us. In fact, I am thinking of making a blog just to archive my posts and not lose the gazillion of hours I invested in writing them up.


Rune. Also, welcome back!


In the beginning the universe was created. This has made a lot of people very angry and been widely regarded as a "bad move"

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#21 2012-02-24 19:59:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,978

Re: Carbon and Carbon Monoxide

That was funny sanman and welcome back....

As for the concentrating of solar with mirrors it could be done with reflective mylar thermal blankets as mars does not have the wind to distroy it.
Just make a backing for it to lay against to form the desired shape and look out.....

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