Author Topic: Proposed ITS Cargo Modules to Initiate a Chemical Industry on Mars  (Read 6841 times)

Offline Ionmars

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NSF Post 1-16-2017 (Updated May 5, 2017)
Proposed ITS Cargo Modules to Initiate a Mars Chemical Industry

Previous NSF threads in SpaceX Mars:

Thread: “Standardized Cargo Container System for Cargo ITS”
https://forum.nasaspaceflight.com/index.php?topic=40454.0

Thread: “ITS Tankers for ISRU/storage”
https://forum.nasaspaceflight.com/index.php?topic=41329.0

Thread: “Passenger MCT as a potential Mars Habitat”
https://forum.nasaspaceflight.com/index.php?topic=37995.0

If you would like to read certain parts of the paper, here is a TOC:

                       Table of Contents (Updated May 5, 2017)
Abstract
Nomenclature
I. Introduction
II. ITS Cargo Vessel as a Standard Pressurized Module
   A. Size and Configuration of the Cargo Module
        B.Six Methods for Delivering a Cargo Module to Mars
   C. Alternative Methods for Unloading the Cargo Module
   D. Estimated Volumes of Alternative Modules
III. Priorities for the Mars Chemical Industry
IV. Example Modules
   A. A Standard Module for Chemical Storage
   B. An Atmospheric CO2 Cleaning Process
   C. A Sabatier Reactor and Electrolysis (SE) Module
   D. Production Rate of the SE Module
   E. An Oxygen-Generating Module
   F. An Atmosphere Separation Module
V. The Initial Chemical Industry
   A A Propellant Tank Farm
   B. . Required Propellant Production and Storage Modules for a Propellant Tank Farm
VI. Summary and Conclusions

To review the new draft, please go to the new thread in L2 by the same title.
« Last Edit: 05/05/2017 10:28 PM by Ionmars »
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Offline Ionmars

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UPDATE
Lamontagne, Bsenna, and I are coauthors on this paper with the help of reviews by sghill and Rei, all participants in NSF forums. An abstract was formally submitted to AIAA for a paper to be presented at SPACE 2017 Conference this year. (See attached file.)

Comments are very welcome and will be considered for the draft paper, which is under vigorous development.
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Offline Port

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on that note O2, CH4, H2O, H2 are all fine but where is all the bio aviable N2 (in the form of NH3 or NO3-salts) coming from? the atmosphere barely contains CO2 if anything, usually you can't find it rock formations..so where to get it from? (and you would need lots for chemistry and especially agroculture)

Offline guckyfan

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on that note O2, CH4, H2O, H2 are all fine but where is all the bio aviable N2 (in the form of NH3 or NO3-salts) coming from? the atmosphere barely contains CO2 if anything, usually you can't find it rock formations..so where to get it from? (and you would need lots for chemistry and especially agroculture)

A mix of nitrogen and argon will be a byproduct of fuel ISRU. Plenty of it as there is plenty of propellant needed. Gaseous nitrogen can be processed into bio availabe compounds. The amounts needed for agriculture would be miniscule compared to fuel production.

Offline Ionmars

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Yes, one of the example applications is a four-step atmospheric CO2 cleaning process, whereby the third step is CO2 freeze-out. After separating out most of the CO2 the reming airflow has high concentrations of Ar and N2. We save these byproducts in a module used for chemical storage for exactly the applications you mentioned. [edit:] Plus make-up air for habitats when mixed with O2 and a few other ingredients.
« Last Edit: 03/05/2017 10:03 PM by Ionmars »
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Offline lamontagne

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I think the availability of N2 in the Martian atmosphere is one of the greatest selling point of the planet.
Does anyone know anything about small local fertilizer plants?  I'm hoping there is a market for local production of NH3 for fertilizer, possibly using some other technology than the Haber process that could serve as a precursor for a Martian production system of NH3.
Bioreactors fixing nitrogen directly into 'soil' in large volumes would be nice, perhaps, if the bug don't need overly exotic foods...

Otherwise a mini Haber process plant would have to do.






Offline Ionmars

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In the paper we have "33 essential chemicals for the chemical industry." Haber process could be done in one module to produce nh3.
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Offline meekGee

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Awesome thread.

Under Calcium Carbonate, I was expecting to see "Cement" as a product.

-------
I think Si should be on the short list.

It's the basis for glass (which is a great engineering material), and for many "pasty" materials for construction.  It should be available in the soil of course, in various compounds.

I don't want to jump to semiconductor ideas (solar cells, etc) since the industrial base required to support such plans is very deep, but at a later point, this will happen too, and power is at the basis of everything on Mars.
« Last Edit: 03/05/2017 03:46 PM by meekGee »
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Offline guckyfan

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I think the availability of N2 in the Martian atmosphere is one of the greatest selling point of the planet.
Does anyone know anything about small local fertilizer plants?  I'm hoping there is a market for local production of NH3 for fertilizer, possibly using some other technology than the Haber process that could serve as a precursor for a Martian production system of NH3.
Bioreactors fixing nitrogen directly into 'soil' in large volumes would be nice, perhaps, if the bug don't need overly exotic foods...

Otherwise a mini Haber process plant would have to do.

NSF member sghill is running a company that develops such a system. Suitable for farmers to produce their own nitrogen fertilizer instead of buying it from industry using the Haber Bosch process.

Quote
Plasma activated water nitrate synthesis is possible though.

Offline Ionmars

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Awesome thread.

Under Calcium Carbonate, I was expecting to see "Cement" as a product.

-------
I think Si should be on the short list.
...
...
I also think silicon will be a valuable material. I probably would put it on a priority list of (solid) minerals to develop, rather than here, just because the paper addresses pressure vessels to be employed in industry, which generally means liquids and gases.

I will see if cement was mentioned by CICE, which is the source of the priority list. Remember, though, that regular water-based cementitious products won't work on Mars because the water will sublimate faster than the cement can cure, according to industrial sources.

Edited: grammar
« Last Edit: 03/05/2017 09:55 PM by Ionmars »
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Offline meekGee

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Awesome thread.

Under Calcium Carbonate, I was expecting to see "Cement" as a product.

-------
I think Si should be on the short list.
...
...
I also think silicon will be a valuable material. I probably would put it on a priority list of (solid) minerals to develop, rather than here, just because the paper addresses pressure vessels to be employed in industry, which generally means liquids and gases.

I will see if cement was mentioned by CICE, which is the source of the priority list. Remember, though, that regular water-based cementitious products won't work on Mars because the water will sublimate faster than the cement can cure, according to industrial sources.

Edited: grammar
Yes, that makes sense. A lot of construction might occur under pressure though, plus I am not sure you can solve the sublimation problem.

$20 says there's a Mars environmental chamber at SpaceX and that it is busy.
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Offline CuddlyRocket

Under Calcium Carbonate, I was expecting to see "Cement" as a product.

I will see if cement was mentioned by CICE, which is the source of the priority list. Remember, though, that regular water-based cementitious products won't work on Mars because the water will sublimate faster than the cement can cure, according to industrial sources.

Yes, that makes sense. A lot of construction might occur under pressure though, plus I am not sure you can solve the sublimation problem.

Water evaporates, ice sublimates! :)

In order for the cement to cure, liquid water needs to react with the calcium oxide in the cement, and the whole process takes well over a day. So, apart from the water evaporating (boiling?) in the low atmospheric pressure, it also rapidly freezes in the low temperatures, stopping the curing process. You could no doubt overcome both problems with temporary pressure and heating, but it adds to the effort required. Plus, water has a lot of other valuable uses on Mars.

There have been experiments with using liquid sulfur as the binding agent to make concrete (arXiv paper) with promising results. The main problem is that it's flammable, though this doesn't matter for most purposes on Mars. Presumably, a module for the production of sulfur would  come in handy!

Offline meekGee

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Under Calcium Carbonate, I was expecting to see "Cement" as a product.

I will see if cement was mentioned by CICE, which is the source of the priority list. Remember, though, that regular water-based cementitious products won't work on Mars because the water will sublimate faster than the cement can cure, according to industrial sources.

Yes, that makes sense. A lot of construction might occur under pressure though, plus I am not sure you can solve the sublimation problem.

Water evaporates, ice sublimates! :)

In order for the cement to cure, liquid water needs to react with the calcium oxide in the cement, and the whole process takes well over a day. So, apart from the water evaporating (boiling?) in the low atmospheric pressure, it also rapidly freezes in the low temperatures, stopping the curing process. You could no doubt overcome both problems with temporary pressure and heating, but it adds to the effort required. Plus, water has a lot of other valuable uses on Mars.

There have been experiments with using liquid sulfur as the binding agent to make concrete (arXiv paper) with promising results. The main problem is that it's flammable, though this doesn't matter for most purposes on Mars. Presumably, a module for the production of sulfur would  come in handy!

That, it does.

I was thinking of cement in the context of the often-discussed tunnels, or general construction of the sort - under normal temperature and pressure.  I don't think water will be a problem underground.  Too much water might be.

For outdoor structures such as pads - glass?  Energy intensive, but easy to make.  (not just landing pads - any base for heavy equipment.)

However - the talk is deviating from the gas-based processes that the thread founders have envisioned.  I think there's a cement thread somewhere already on the non-SpaceX Mars threads.
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Offline guckyfan

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We had the concrete discussion on Mars threads and on the Amazing Martian Habitats threads. There is Marscrete, that solves all these problems, with materials easier sourced than our cement based concrete and less energy to produce.


Offline Ionmars

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We had the concrete discussion on Mars threads and on the Amazing Martian Habitats threads. There is Marscrete, that solves all these problems, with materials easier sourced than our cement based concrete and less energy to produce.


Thanks for sharing. I appreciate Brandon Larson's progress toward practical Mars construction. (!)
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Offline AncientU

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This is exactly the type of project that is too complex to validate in situ with robotics, but early crews on Mars will be able to finish relatively easily.  You can only get so far in the lab... sounds promising with what has been done so far, but the proof will be in the development efforts by boots on the ground on Mars, using actual surface resources and environmental conditions.
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Offline Lar

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I would love to see a draft of this, happy to sign NDA, realise it's probably way too late for any suggestions, but just wanted to post that....

...AND that I think it's amazingly awesome that a web based resource like this (originally a bunch of shuttle huggers) is actually facilitating submission of meaningful scientific papers.
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Offline Ionmars

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I would love to see a draft of this, happy to sign NDA, realise it's probably way too late for any suggestions, but just wanted to post that....

...AND that I think it's amazingly awesome that a web based resource like this (originally a bunch of shuttle huggers) is actually facilitating submission of meaningful scientific papers.
Thanks.
Truth is, we love to do stuff that other people consider hard work. (Don't tell anyone.)

In a few weeks we should have a good draft for your review on this thread. (!) Sharpen your pencils.
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Offline sghill

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I think the availability of N2 in the Martian atmosphere is one of the greatest selling point of the planet.
Does anyone know anything about small local fertilizer plants?  I'm hoping there is a market for local production of NH3 for fertilizer, possibly using some other technology than the Haber process that could serve as a precursor for a Martian production system of NH3.
Bioreactors fixing nitrogen directly into 'soil' in large volumes would be nice, perhaps, if the bug don't need overly exotic foods...

Otherwise a mini Haber process plant would have to do.

NSF member sghill is running a company that develops such a system. Suitable for farmers to produce their own nitrogen fertilizer instead of buying it from industry using the Haber Bosch process.

Quote
Plasma activated water [PAW] nitrate synthesis is possible though.


The 2.7% nitrogen content on Mars will be separated out of the rarefied martian atmosphere for any fuel in situ scheme, so it is a given that it will be done (likely using cryogenic separation) and some levels of local sourced nitrogen will be available.

Turning collected the nitrogen gas into nitrite, nitrate, and peroxide then requires the addition of water and electricity using a PAW process.
« Last Edit: 03/06/2017 07:51 PM by sghill »
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Offline Ionmars

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PLEASE tell us about PAW.

Edit:  :)
« Last Edit: 03/06/2017 10:39 PM by Ionmars »
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Offline Lar

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might be proprietary or under patent review so he may not be able to give a lot of detail, but yes please
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Offline Ludus

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It would also be interesting to see how the different proposed Farings of an ITS Cargo Variant would work for alternative ITS missions and uses other than Mars. Like deploying satellite constellations, Bigelow modules or other spacecraft in earth orbit, outer solar system missions etc.

Offline sghill

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PLEASE tell us about PAW.

Edit:  :)

See attached white paper from one of the inventors. The table on page 5 is of particular interest. PAW isn't the only technology, but it's by far the simplest with the least damaging process. The electricity use is higher than Haber-Bosch, but in a martian context, electricity use isn't as big a factor as getting feedstock and not damaging your extremely small enclosed system.
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Offline CraigLieb

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Coming from a facilities maintenance perspective, pay attention to maintainability.

Filters have to be changed, pumps and such have to be replace, repaired and serviced.
Belt drives wear out, gears get fouled (especially in a dusty environment),  etc.
Consider space for access ladders, platforms, hoists to lift up equipment and lower down equipment.

The shell of the container creates a barrier to entry which helps protect against environmental issues, but also requires access doors to ingress and bring in/out equipment.

Unknowns are all around you like what does this equipment work like in a different atmosphere, with different gravity?  At least make a head-nod in the plan and diagrams to a pump/equipment room, access issues, etc. This would go a long way towards making the modules look more realistic.

Why have a separate half shell on ITS?  Would you consider making the side wall (top half) of the module the outer skin of ITS and have it be removable/replaceable. This makes access to the module much easier. The residents can use sheeting temporarily, and then material constructed on Mars from these other chemicals to enclose the open modules. The half shell is could then be replaced on the ITS and returned to Earth, saving the weight of double walls.  for that matter, the whole module could be more like a ribbed cage which has sections for securing the wrapped wall material which will be constructed on Mars. This saves a lot of weight.



Colonize Mars!

Offline Ionmars

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Coming from a facilities maintenance perspective, pay attention to maintainability.

Filters have to be changed, pumps and such have to be replace, repaired and serviced.
Belt drives wear out, gears get fouled (especially in a dusty environment),  etc.
Consider space for access ladders, platforms, hoists to lift up equipment and lower down equipment.
...
...
You are right on target. We addressed the maintenance and acces issue in our Jan draft  Here is an excerpt from the section regarding a Sabatier-Electrolysis module:

"To extrapolate the production rate of a small Sabatier unit to an ITS reactor module, one requires a linear volumetric expansion factor (F). This assumes that a compact plumbing arrangement will be found for the SE Module that is comparable to the plumbing efficiency of the prototype unit. Any near-term advances in design technology are not considered. Of the 1860 m3 volume of the SE module one may allocate 600 m3 for crew access for maintenance and for additional plumbing to tie together multiple reactors (Estimate by the Author). Thus we have
FCH4 = 1260 m3 / 1.571 m3 = 802."

Do you think this is adequate?
I am updating this section III, subsections C and D this week with revised module volumes. Do you have ideas about how to arrange equipment for maintenance access? 
Edit: Does anyone?
« Last Edit: 03/10/2017 02:49 PM by Ionmars »
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Offline CraigLieb

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seems like a good start.
Maybe too early in concept to show it in diagrams too access, ladders, pump platforms.
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Offline Ionmars

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seems like a good start.
Maybe too early in concept to show it in diagrams too access, ladders, pump platforms.
You are right. When one of these types of cargo vessels is adopted by SpaceX there will be 33 module variations to design in detail!  :)
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Offline Ionmars

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The technical paper has now been approved for presentation at the AIAA Conference SPACE 2017. :)

Please see the updated info in Reply #1 or go to L2 - new thread of same title.
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Offline gospacex

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What about making polyurethane? It's a liquid, and requires only C, O, N.

I tried mixing polyurethane lacquer with sand - the result is a sort of "plastic concrete". Sand on Mars is readily available, even sorted by size in dunes...

Offline Ionmars

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As of this week, the final technical paper was uploaded to AIAA and accepted.
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Online tdperk

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What about making polyurethane? It's a liquid, and requires only C, O, N.

I tried mixing polyurethane lacquer with sand - the result is a sort of "plastic concrete". Sand on Mars is readily available, even sorted by size in dunes...

Can it cure in the Martian atmosphere?  (Or would it need baking and pressurization?)

Either way, add glass fiber and you've got a good engineering material.

Offline Ionmars

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What about making polyurethane? It's a liquid, and requires only C, O, N.

I tried mixing polyurethane lacquer with sand - the result is a sort of "plastic concrete". Sand on Mars is readily available, even sorted by size in dunes...
I really like your idea. Following tdperk, we should test it in a vacuum chamber.
If this works, the process would readily fit into the modular chemical industry described in the paper I mentioned above . The carbon and oxygen could be derived from an oxygen generator module and the nitrogen would be a byproduct of the 4-step CO2 cleaning process. The production of perc and plastic concrete could be a module unto itself.

Would you like to pursueyour idea? I could help.
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Offline Lar

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What about making polyurethane? It's a liquid, and requires only C, O, N.

I tried mixing polyurethane lacquer with sand - the result is a sort of "plastic concrete". Sand on Mars is readily available, even sorted by size in dunes...
I really like your idea. Following tdperk, we should test it in a vacuum chamber.
If this works, the process would readily fit into the modular chemical industry described in the paper I mentioned above . The carbon and oxygen could be derived from an oxygen generator module and the nitrogen would be a byproduct of the 4-step CO2 cleaning process. The production of perc and plastic concrete could be a module unto itself.

Would you like to pursue your idea? I could help.

I would think that this is a natural adjunct to ammonia production so it makes a lot of sense... other poymers may also be natural early products. My favorite one (ABS) , though, is a terpolymer that takes three precursor monomers. Still all  CHON but much more complex. Also much more variable material properties... but probably nont something produced early.


As of this week, the final technical paper was uploaded to AIAA and accepted.


Congrats to your team for the acceptance, well done. (and a thanks to the NSF reviewers that helped... )

That's two years in a row now right? What are you going to do next year? :)
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Offline Ionmars

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...
...
Congrats to your team for the acceptance, well done. (and a thanks to the NSF reviewers that helped... )

That's two years in a row now right? What are you going to do next year? :)
Thank you for the kind words.

The pot of ideas is boiling over, so there is no shortage of material. In this paper we cited a chart of 33 essential chemicals for the chemical industry that would eventually be required on Mars. This table alone could produce 33 PhD dissertations for the detailed designs of specialized chemical reactor modules.

I have two subjects in mind to discuss with potential authors. I can introduce them in due time, but you can bet the titles will contain the word "Proposed."

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