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#51 2018-12-12 19:47:05

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

Constant flow of the Amine solution from the bubbler tank to the heating chamber  via pumps once saturated for releasal and then back through a cooling heat exchanger before send it back into the bubbler chamber to capture more co2. Pump the co2 gas from the heated chamber to be pressurized and cool as we will want to liquify it. Night time would have a cool loop to save the night cold for day time cooling use for both the co2 stage and for cooling the Amine solution for reuse.

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#52 2018-12-13 18:42:45

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

http://www.tcmda.com/en/Technology/Amine-technology/

http://science.sciencemag.org/content/3 … /1652.full

Amine scrubbing has been used to separate carbon dioxide (CO2) from natural gas and hydrogen since 1930. It is a robust technology and is ready to be tested and used on a larger scale for CO2 capture from coal-fired power plants. The minimum work requirement to separate CO2 from coal-fired flue gas and compress CO2 to 150 bar is 0.11 megawatt-hours per metric ton of CO2.

https://web.anl.gov/PCS/acsfuel/preprin … 2_0012.pdf

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#53 2018-12-13 21:07:24

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

People produce carbon dioxide while breathing and it is a the major pollutant in the premises. A typical human exhales about 1 kg of carbon dioxide per day. During sleeping in the high altitude chamber or tent one person produces(exhales) about 5,27 gallons /24 l CO2 per hour. During training in the high altitude training chambers and tents  CO2 hour production rate can be 50 gallons /240 l of pure carbon dioxide(CO2) or even more. That is why CO2 level in the high altitude training facilities in most cases reaches 0,5% or even 1% CO2. ASHRAE recommends indoor CO2 levels not exceed 0,1%. During training/ exercise, the CO2 breath out from the athletic is more than 5000ppm. Without the CO2 scrubber, the CO2 level in the chamber can goes to 7000ppm in very short time. It is not health to athletic. Normal accepts level during exercise is <2000ppm.

https://www.bre.com/PDF/The-Use-of-MDEA … emoval.pdf


Example of what would be used in a room on a mars surface.
http://www.aminescrubber.com/images/AmineScrubber.pdf

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#54 2018-12-13 21:37:09

kbd512
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Registered: 2015-01-02
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Re: In-Situ Propellant Production, design a opensource demonstrator

SpaceNut,

I'm not sure how these atmospheric scrubbers translate into something we can use to liquefy CO2 if the primary power consumption issue is with the pump itself.  Is there a practical way to adsorb and then release enough gaseous CO2 for the LOX/LCH4 plant to operate continuously when the propellant production rate is around 1 ton per day?,  Those scrubbers indicate a cycle time is 2 to 4 hours.  If there is, then why don't any of the ISPP plants purport to use gaseous CO2?  I think we have to bite the bullet on this one and supply enough power.

I was hoping there was a free lunch somewhere in our new technology, but there never seems to be one available.

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#55 2018-12-13 22:20:09

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

Still searching for what will be the best options.
https://ntrs.nasa.gov/archive/nasa/casi … 016419.pdf
Compact and Lightweight Sabatier Reactor for Carbon Dioxide Reduction

https://ntrs.nasa.gov/archive/nasa/casi … 007818.pdf
Mars Atmospheric Conversion to Methane and Water: An Engineering Model of the Sabatier Reactor with Characterization of Ru/Al2O3 for Long Duration Use on Mars

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#56 2018-12-14 17:13:40

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

The inlet to a sabatier reactor is 5 to 7 bar or 75 psi to 100 psi for the CO2 going into it and it should be warm so as to allow the chamber temperature to be in the 200 to 400 range for best conversion. So we are as you put it need to solve for how to get what we need at less energy.

For a mars day we will have 9 hours of daylight and 16 hours of night temperature to make use of give or take and we can use concentrators for the day to elevate the temperatures on the chambers being used for co2 compession and pressurization. Sure its a slow cycle but its free energy.

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#57 2018-12-15 09:25:00

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

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#58 2018-12-15 19:51:13

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

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#59 2018-12-16 19:00:50

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,118

Re: In-Situ Propellant Production, design a opensource demonstrator

Scientists identify new minerals for carbon capture

The minerals, members of the hydrotalcite group, are the first outside of the carbonate family to naturally capture atmospheric CO2 in mine waste, important as society continues to forge ways to lower our carbon emissions and combat climate change.

"This research confirmed that hydrotalcites are capable of sequestering atmospheric CO2 in mine waste," said Connor Turvey, who conducted this research during his PhD studies under the supervision of Sasha Wilson. "Hydrotalcites are trapping the CO2 deeper into the tailings where carbonate minerals were unable to form."

Low-cost catalyst boosts hydrogen production from water

"Our new catalyst is made from copper, nickel and chromium, which are all more abundant and less costly than platinum," says Cao-Thang Dinh, a co-lead author on the paper along with his fellow postdoctoral researchers Pelayo Garcia De Arquer and Ankit Jain. "But what's most exciting is that it performs well under pH-neutral conditions, which opens up a number of possibilities."

Seawater is the most abundant source of water on earth, Dinh points out. But using seawater with traditional catalysts under acidic conditions would require the salt to be removed first, an energy-intensive process. Operating at neutral pH avoids the high cost of desalination.

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