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There's dirt in that there dirt - living off the land on Mars.


KSK

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Hey folks,

As per Nibb31's request, I've started a new thread for discussing Martian colonisation, agriculture, living-off-the-land etc.

A couple of observations to start. Perchlorates aren't neccesarily bad and could be quite useful provided they can be extracted and processed safely. Perchlorate candles, for example, are a well known emergency oxygen supply. Plus you get sodium chloride as a reaction product, so you get some lovely Martian salt to go on those Martian potatoes. :) Also Martian regolith wouldn't make a bad starter for making soil. It'll need a load of water and organic material for sure but it's got plenty of vital minerals.

Edited by KSK
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Mars smells like a swimming pool.  Considering all the horrible things an alien planet could smell like, I don't think this is a bad result.

On second thought this is a really great result, with all those people living indoors for entire lives, in close quarters, with limited fresh water the disinfecting nature of the Mars environment will probably help quite a bit.

Also, Mars appears to be loaded with Calcium Carbonate, which is great because it is the magic bit in CO2 scrubbers for air handling systems.

Sodium, Nitrogen and phosphates have been found in abundance on Mars as well.

Ok, I only have chemistry 101, and it was many years ago.  But heating on mars will be achieved with Acetylene gas, because it will be a byproduct of just about every reaction you do on Mars to make useful stuff out Mars dirt.  The reason that Acetylene gas is used is that ethylene is produced during oil refining, and will be unavailable.  Methane however will be readily available and there will be large scale production of Methane, and can be readily converted into Acetylene as a precursor chemical.

 

Gregs Mars dirt public domain PVC recipe - Elon, are you reading?  I get my name in the credits because of this, right?

Electrolysis of perchlorides, recovery of chlorine and Oxygen.

React chlorine with hydrogen to get HCL.

Synthesize Acetylene gas by getting some methane from the rocket fuel factory, and reacting it in an oxygen constrained environment.

Mix Acetylene gas and HCL gas with a  mercuric chloride catalyst and get vinyl chloride.

Add water to the vinyl chloride and an initiator (all wildly out of my chemistry ability but only a tiny amount is needed as it is a chain reaction) and you get a vat of PVC, which only needs to be dried and sieved before use.

This yields a product that is similar in consistency to vinyl siding, not as flexible as PVC pipe for example.  It loses strength at 140C, and is very cold resistant.  It will however degrade over time if exposed to certain types of bacteria and fungus.

Edited by GregA
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Ok I slept on it a little bit.  One of the rovers on mars found clay.  That means is should be possible to simply build soil up from Hydroton growth media, and fabricate fertilizer from local elemental nutrients, nitrates, phosphates and calcium, while only needing to import a small amount of micro-nutrients from Earth..  Colonists could even spin rockwool from silicates that are freely available everywhere on mars...

Hydroton works out great because the clay is fired sealing the growth media into a fired clay ball, rending it inert as a nutrient (or contaminant) source. 

IMO, it is easier to grow with hydroponics on mars than fabricate earth like topsoil.

I just about have poly-carbonates from Mars soil worked out as well.

I think we can conclude the first settlers are all going to be chemists...

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9 hours ago, GregA said:

Mars smells like a swimming pool.  Considering all the horrible things an alien planet could smell like, I don't think this is a bad result.

On second thought this is a really great result, with all those people living indoors for entire lives, in close quarters, with limited fresh water the disinfecting nature of the Mars environment will probably help quite a bit.

Also, Mars appears to be loaded with Calcium Carbonate, which is great because it is the magic bit in CO2 scrubbers for air handling systems.

Sodium, Nitrogen and phosphates have been found in abundance on Mars as well.

Ok, I only have chemistry 101, and it was many years ago.  But heating on mars will be achieved with Acetylene gas, because it will be a byproduct of just about every reaction you do on Mars to make useful stuff out Mars dirt.  The reason that Acetylene gas is used is that ethylene is produced during oil refining, and will be unavailable.  Methane however will be readily available and there will be large scale production of Methane, and can be readily converted into Acetylene as a precursor chemical.

 

Gregs Mars dirt public domain PVC recipe - Elon, are you reading?  I get my name in the credits because of this, right?

Electrolysis of perchlorides, recovery of chlorine and Oxygen.

React chlorine with hydrogen to get HCL.

Synthesize Acetylene gas by getting some methane from the rocket fuel factory, and reacting it in an oxygen constrained environment.

Mix Acetylene gas and HCL gas with a  mercuric chloride catalyst and get vinyl chloride.

Add water to the vinyl chloride and an initiator (all wildly out of my chemistry ability but only a tiny amount is needed as it is a chain reaction) and you get a vat of PVC, which only needs to be dried and sieved before use.

This yields a product that is similar in consistency to vinyl siding, not as flexible as PVC pipe for example.  It loses strength at 140C, and is very cold resistant.  It will however degrade over time if exposed to certain types of bacteria and fungus.

Great, now how do we turn a chem-lab process into an industrial one?

For PVC, lets go down your steps...

Step 0: separating the perchlortes from the soil and other nutrients. Washing it out is easy, but how do you purify the perchlorates?

Electrolysis of a dissolved base, what kind of equipment is needed for this, and to capture and separate chlorine and oxygen? (cant be too hard, I saw a documentary saying that this was how potasium was discovered, shortly after the battery was invented)

"Burning" chlorine and (water-electrolized) hydrogen. Likely to be violently exothermic, so design may bemore complicated than first glance suggests.

Acetylene production- looks to be straightforeward with the right equipment

Mercuric Cloride catalyst- is the quantity small enough that it's worth bringing from earth, or is it easier to make on site?

"Initiator"- Need the final special sauce.

Presumably you should also have extrusion equipment to make useful stuff from the PVC.

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I've got an alternative route to hydrochloric acid, Greg which might be a bit easier on Mars. Might. :)

Step 1. Direct iron reduction. 

Natural gas is partially oxidized (with heat and a catalyst
2 CH4 + O2 → 2 CO + 4 H2
These gases are then treated with iron ore in a furnace, producing solid sponge iron:
Fe2O3 + CO + 2 H2 → 2 Fe + CO2 + 2 H2O
Silica is removed by adding a limestone flux.

Step 2. Perchlorate candles

4NaClO4 + 4Fe ---> 4NaCl + 2Fe2O3 + 5O2


Step 3. Electrolysis of brine to hydrochloric acid.

 

Rationale. 

Iron is generally useful for lots of things (as a catalyst in the Haber process if nothing else) and its also heavy. Producing it in-situ rather than hauling it from Earth is probably going to happen somehow. Reducing iron ores with carbon isn't ideal - making coke on Mars might be tricky. :)  On the other hand we have boatloads of methane, assuming that we're going with the SpaceX plan of using methalox engines for our Mars vehicles. Carbon monoxide and hydrogen (aka syngas) are also useful to have around if we're bored of using them to reduce iron oxide.

Not sure if there's much to choose between brine electrolysis and perchlorate electrolysis. The latter sounds nastier to me but I don't have anything other than gut feel to back that up. Brine electrolysis does at least have the advantage that we've been doing it forever and so have plenty of experience with it. Also, the perchlorate candle step produces iron oxide which can be recycled through Step 1.

 

 

 

 

 

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Problem is that apparently mars has a lot more Calcium Perclorate and Magnesium Perchlorate than sodium or alunimum perchlorate.

 

" Unexpected though was the presence of ~0.6% by weight perchlorate (ClO
4
), most likely as a mixture of 60% Ca(ClO4)2 and 40% Mg(ClO4)2 "

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I don't think that will be a problem. Calcium perchlorate should work OK in a candle (?), giving you calcium chloride rather than sodium chloride and calcium chloride solution can be electrolysed, although brine is more usual on Earth.

I'm spitballing here though, don't know how well calcium perchorate will react with iron.

Edited by KSK
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Basic science question for the real life chemists out there...  Where did the fixed nitrates on Mars come from?  I thought fixed nitrates on Earth came from biological processes?

Anyhow, here is a device that makes pure water and enriched brine, and pure water is going to be an issue on Mars with all the salts everywhere..

 

https://www.google.com/patents/US5458781

Edited by GregA
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2 hours ago, KSK said:

I don't think that will be a problem. Calcium perchlorate should work OK in a candle (?), giving you calcium chloride rather than sodium chloride and calcium chloride solution can be electrolysed, although brine is more usual on Earth.

I'm spitballing here though, don't know how well calcium perchorate will react with iron.

Counter ion shouldn't be a problem, as far as I know. Instead of using methane, you can go direct from CO2 to CO, safe a step.

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What I'm wondering about is how the settlers will grow all their food.  Obviously hydroponics will be a big part of it, but some plants don't do well in hydroponic systems, and of course how will they get the necessary protein.  I am of the opinion that at some point someone will have to bring some form of livestock to help supplement their diet.  Rabbits would be the best choice in my mind because they breed quickly and have a versatile diet, e.g. vegetable scraps or grass.  The offal from the butchering process could be composted with the waste from the toilet facilities (because you wouldn't just throw that out).  Really the only way the whole thing will even work is with a recycling/composting mindset.

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3 minutes ago, Thor Wotansen said:

What I'm wondering about is how the settlers will grow all their food.  Obviously hydroponics will be a big part of it, but some plants don't do well in hydroponic systems, and of course how will they get the necessary protein.  I am of the opinion that at some point someone will have to bring some form of livestock to help supplement their diet.  Rabbits would be the best choice in my mind because they breed quickly and have a versatile diet, e.g. vegetable scraps or grass.  The offal from the butchering process could be composted with the waste from the toilet facilities (because you wouldn't just throw that out).  Really the only way the whole thing will even work is with a recycling/composting mindset.

Here is a video of what I think it will probably look like...  Except it will be indoors, with high intensity lights...  These guys are using Tilipia fish as their protein.

 

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1 hour ago, Thor Wotansen said:

What I'm wondering about is how the settlers will grow all their food.  Obviously hydroponics will be a big part of it, but some plants don't do well in hydroponic systems, and of course how will they get the necessary protein.  I am of the opinion that at some point someone will have to bring some form of livestock to help supplement their diet.  Rabbits would be the best choice in my mind because they breed quickly and have a versatile diet, e.g. vegetable scraps or grass.  The offal from the butchering process could be composted with the waste from the toilet facilities (because you wouldn't just throw that out).  Really the only way the whole thing will even work is with a recycling/composting mindset.

I would vote for sheep and pigs. Pigs are great at eating trash basically, and sheep also give you milk and wool products. 

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The main problem with larger animals is just getting them there.  Try to imagine something like a pig in 0g.  The other option is to have a centrifuge big enough to house breeding stock for the 6ish month trip and some kind of seat/couch to support them during high G maneuvers.  Rabbits, on the other hand, can be housed in a much smaller space and take a lot less time to be fruitful and multiply.  You can also generally eat an entire rabbit in one meal, which makes food storage easier.

Fish are something I have very little little experience with.  I'll look into them a bit more though.

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There is lab grown meat, it is already at a stage where it is edible and you have 15-20 years to develop into being palatable.

Then ofcourse there is insects, massive protein density, minimal volume/mass rapid breeding rate.

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1 hour ago, Thor Wotansen said:

The main problem with larger animals is just getting them there.  Try to imagine something like a pig in 0g.  The other option is to have a centrifuge big enough to house breeding stock for the 6ish month trip and some kind of seat/couch to support them during high G maneuvers.  Rabbits, on the other hand, can be housed in a much smaller space and take a lot less time to be fruitful and multiply.  You can also generally eat an entire rabbit in one meal, which makes food storage easier.

Fish are something I have very little little experience with.  I'll look into them a bit more though.

Apparently science has frozen trout for multiple years, thawed, fertilized the eggs and produced viable offspring...  That has to be the lowest mass way to get Livestock to Mars initially.

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29 minutes ago, todofwar said:

Really it will probably be a vegetarian diet with a specially modified bacteria or yeast that will produce essential nutrients that are hard to get from plant sources. 

Well that is the beautiful part of the SpaceX plan.  Anyone who can afford a ticket can go and do whatever they want.  The colony will be designed by capitalist forces, not a bunch of bureaucrats deciding that there should be nothing in the way of creature comfort with some crazy political agenda like "in the 22nd century all humans should be vegetarians", or "free college for everyone."

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23 minutes ago, GregA said:

Well that is the beautiful part of the SpaceX plan.  Anyone who can afford a ticket can go and do whatever they want.  The colony will be designed by capitalist forces, not a bunch of bureaucrats deciding that there should be nothing in the way of creature comfort with some crazy political agenda like "in the 22nd century all humans should be vegetarians", or "free college for everyone."

Looking forward to that one colonist who will bring some weapons and have everybody else "volunteer" to feed him.

I'm not sure if the plan “and everybody has to figure out for themselves how they are going to provide air, water and food for themselves” is the ticket for success for a thriving Mars colony. Maybe it is. But I wouldn't bet on it.

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42 minutes ago, Kerbart said:

Looking forward to that one colonist who will bring some weapons and have everybody else "volunteer" to feed him.

 Wonder if this qualifies as a viable "Do whatever you want" option. lol

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36 minutes ago, Talavar said:

 Wonder if this qualifies as a viable "Do whatever you want" option. lol

The IRS paperwork quite clearly states that paying taxes is voluntary.  lol.  If anything I bet living in a society where airlock accidents are a daily possibility, folks will be hyper polite to one another.

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6 hours ago, todofwar said:

Pigs are great at eating trash basically, and sheep also give you milk and wool products. 

 

6 hours ago, GregA said:

Chickens will just be there.

Chickens eat whatever even the pigs feel disgusting. Brainless reptiles, by all means.
So, why pigs?

Also, as the chickens will live in a dome, in warm artificial conditions, they don't need feathers.
(Which take a lot of energy and food to grow, as any protein structure, but are absolutely useless, unless to make cushions.).

They will live in a very stretched room, so they don't need wings and legs. Even more, these parasite structures only decrease the biocycle efficiency.

Their only food will be an organic pulp made of algae and biological wastes. So, they don't need nibs or teeth.

As the pulp can be pre-digested before feeding the chickens, they don't need digesting system, only the absorbing one. No need in stomach and liver.

Of coursem they absolutely don't need any sensors. Eyes, brains, ears, other inedible trash.

So, a Martian chicken would should must ought to be a genetically modified piece of flesh intubed from front and rear ends with pulp lines.

Next step: monocellular culture of chicken algae. Then even no pulp lines, just a vat with pump.

P.S.
Not joking.

P.S.S.
About perchlorates.
Physics beats chemistry. Set a powerplant and set the sand on fire.
 

 

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