Author Topic: Proposed ITS Cargo Modules to Initiate a Chemical Industry on Mars  (Read 16631 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)

Online 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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Online 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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Online 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.

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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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Offline 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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Offline Ionmars

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Update:
A hurricane crossing Florida prompted the American Institute of Aeronautics and Astronautics to cancel the meeting SPACE 2017 that was planned to be held in Orlando. The paper was never presented, but all 400 papers are available to the public for the next 3 months at no charge.

To download, go to AIAA.com. On the home page, click on Aerospace Research Center (ARC), then select "Meeting Papers" and click on AIAA Space Forum(s). Go down the list to 2017 Space and Astronautics Forum and Exposition. Then go down the list of sessions to SYS-05 Systems Architecture and Analysis, where you will find paper AIAA 2017-5335 is the first one.
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Offline Ionmars

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I have the slides for the presentation, so here they are in the attached file. You may have to read some of the paper to fill in the gaps because the slides are not accompanied by the talk.
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Offline Llian Rhydderch

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Will be interesting to see what sort of scale your chem processing might be able to do in the much smaller cargo spaceships that Musk outlined last week at IAC2017.

Can your processes scale down and fit in the smaller modules, just at a lessened chem ops capability?  Or would some of your processes require the larger process line, say distillation towers, etc.?
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Offline Ionmars

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Will be interesting to see what sort of scale your chem processing might be able to do in the much smaller cargo spaceships that Musk outlined last week at IAC2017.

Can your processes scale down and fit in the smaller modules, just at a lessened chem ops capability?  Or would some of your processes require the larger process line, say distillation towers, etc.?
Yes, we used a linear volumetric model to scale from the ISS prototype Sabatier reactor to the large ITS/BFS module. We would just use a different volume for the scaled-down version. The projection factors are just ratios of volume (module) / volume (prototype) times propellant production rate (prototype). The propellant tanks to be filled would also scale linearly by volume; so the number of modules required to fill them should remain about the same, even though their size is different.

This is something I had planned to do, but I am working heavily on the next paper. If you wish, you could look at the volumetric factors in the paper and give it a shot. I would be interested also.
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Offline Robotbeat

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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...
Polyurethane is aromatic, so you're going to have to make Benzene or similar at some point.

Polyurethane or epoxies are probably essential for industry. Much harder to make than polypropylene, etc, though.
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Offline Katana

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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...
Polyurethane is aromatic, so you're going to have to make Benzene or similar at some point.

Polyurethane or epoxies are probably essential for industry. Much harder to make than polypropylene, etc, though.
PU could be aliphatic instead of aromatic, quite common. But manufactuing either needs many steps, including polyols and isocynates.

Bitumen from soot and tar is already strong enough in freezing environment.

Offline CW

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Is polyurethane photo-stable under sunlight? I mean, would it be damaged by sunlight? Couldn't find any info on that so far.. .
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Offline speedevil

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Is polyurethane photo-stable under sunlight? I mean, would it be damaged by sunlight? Couldn't find any info on that so far.. .

It will be damaged somewhat, various additives, going all the way to as simple as soot help with that.

Offline ThereIWas3

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Semiconductors are more than Silicon.  There also carefully controlled amounts of other elements and maybe minerals.  (I did take a course in this 45 years ago and have forgotten the details.  All I remember is hairy math involving the concentration probabilities of subatomic particles and quantum stuff.  Probably different now anyway.). It is real nano manufacturing.

I can not think of any reason these elements would NOT be present on Mars, especially in volcanic regions.  But they have to be found and extracted.
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Offline speedevil

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Semiconductors are more than Silicon.  <snip>
I can not think of any reason these elements would NOT be present on Mars, especially in volcanic regions.  But they have to be found and extracted.
Modern fabs cost well over a billion dollars.
Yes, you can possibly do interesting useful things with a lower cost fab, but the earth fab has the free availability of all perfectly refined substances essentially free, as well as being mass unconstrained, and easy servicing of machines.

The actual active parts of a chip are ~0.3mm thick at most, so ~0.06g/cm^2, and cost perhaps $20/cm^2. Or $300/g. $300000/kg.

You'd have to be barking mad to try to make them on Mars, for the forseable future. (When you have several million people perhaps).

Even lightweight assembled electronics, are often well over $1000/kg, and it's questionable even in the medium term.

The actual weight of silicon in the active parts of your computer is probably several grams.

(you can thin the silicon to under a tenth of this thickness, microSD cards, for example are typically ten chips laminated on top of each other.)

Offline Robotbeat

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Computer chips are so small that, with BFR doing logistics, shipping costs are essentially free and there's no reason to make computer chips on Mars.

Different story for power electronics and solar cells, though. A low-resolution fab is just fine for those. It'll be a while until that's necessary, tho.

As far as self-sufficiency, you could fit about a trillion computer chips (not counting packaging, which could be done on Mars) as powerful as the Apollo guidance computer in your pockets. Just stock up! And the low-res power electronics fab could make computer chips in a pinch, but there's no reason to do that.
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Offline ThereIWas3

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Big complex chips, maybe, but here is a YouTube video of engineer Jeri Ellsworth .  Maybe something Mark Watney would know how to do...
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Offline speedevil

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Big complex chips, maybe, but here is a YouTube video of engineer Jeri Ellsworthorth

I'm aware of Jeris work. She has made unreliable low-current, poor performance chips, using commercially produced pure silicon wafers.
This is very similar to the 1952 demonstration of the first IC.

It's as helpful to general electronic use as a black powder rocket is to getting to Mars.

As a general point, modern processes make not only better, but smaller area chips, that are lower power.
A ton of fabricated silicon chips will last a small colony for many years.

Even solar cells are not hideously expensive to ship.
A ton of solar cells will (on earth) cost you $.50/W or so, which is ~$70/m^2 , at .3mm thick, $210K/m^3, or $80K/ton. $80/kilo or so, which is somewhat indicative of how hard they are to make.

You'd want to be able to make the glass on Mars, if using conventional panels - but even at .3mm thick (thinner ones are now generally used, and are worst case), it's quite sane to ship.


Offline Ionmars

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 So many chemicals. So many industries. Here is Lamontagne's rendering of a chemical complex on Mars:  :)

Edit: spelling
« Last Edit: 02/05/2018 01:25 PM by Ionmars »
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Offline biosehnsucht

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If there's some kind of crane assembled to remove / move the chemical processing units, then the satellite deploying version of BFS as cargo to Mars would work pretty well for landing large containerized units like described in the paper/slides.



It seems the jaw would have to open up more than 90 degrees, and the containerized unit removed somewhat horizontally initially, to clear the top of the BFS, before it can be lifted. Or perhaps only partially as depicted, but the crane would have to unload it both horizontally and vertically at the same time? I'm going to assume the hinge working in Martian gravity will be fine as it would need to work in Earth gravity to load it in the first place before launching things in Earth orbit from it (though possibly assisted externally with support, that could be arranged by assembling similar mechanisms at Mars).
« Last Edit: 10/06/2017 03:37 AM by biosehnsucht »

Offline Ionmars

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If there's some kind of crane assembled to remove / move the chemical processing units, then the satellite deploying version of BFS as cargo to Mars would work pretty well for landing large containerized units like described in the paper/slides.
...
...
It seems the jaw would have to open up more than 90 degrees, and the containerized unit removed somewhat horizontally initially, to clear the top of the BFS, before it can be lifted. Or perhaps only partially as depicted, but the crane would have to unload it both horizontally and vertically at the same time? I'm going to assume the hinge working in Martian gravity will be fine as it would need to work in Earth gravity to load it in the first place before launching things in Earth orbit from it (though possibly assisted externally with support, that could be arranged by assembling similar mechanisms at Mars).
I also noticed that image in the presentation. Lamontagne posted that same in-space release of a cargo vessel on NSF some time before IAC 2017, but I don't recall which thread.
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Offline Ionmars

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The purpose of the unhinged lower panel is to allow the entire heatshield side of the spaceship to be produced as one piece. When we proposed this as an option in the paper, we didn't know that SpaceX would want to develop this capability. Apparently they do.

The release of the vessel may be easier on Mars surface. We proposed a "vessel grappler" that could remove the vessel from the side. Also the half-fairing is a removable panel rather than hinged, so it is removed and set aside.

Edit: spelling
« Last Edit: 10/06/2017 12:56 PM by Ionmars »
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Offline Ionmars

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Lamontagne has already suggested a method for releasing the vessel into space. The half-fairing would be hinged as depicted in the presentation and the vessel attached to it. When the hinged panel opened, the vessel would come with it. When the vessel cleared the nose of the heatshield side, pusher rods would discharge it away from the ship.
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Offline Llian Rhydderch

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Seems like if the large containers have high usefulness on Mars, the 50 tonne return payload to Earth might be contained in ISS/Shuttle/Drago-type cargo bags and safely secured using some type of military-type strap-down system.  All of that gear could be carried to Mars collapsed and compressed.  Example:
Re arguments from authority on NSF:  "no one is exempt from error, and errors of authority are usually the worst kind.  Taking your word for things without question is no different than a bracket design not being tested because the designer was an old hand."
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Offline lamontagne

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Latest version of the vessel in Gator configuration.

Volume of pressure vessel payload is about 700 m3, mass of about 16 tonnes.
If used om Mars, I expect a crane could be used to remove the door, and then used to remove the payload.
« Last Edit: 10/07/2017 03:13 AM by lamontagne »

Offline Ionmars

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Seems like if the large containers have high usefulness on Mars, the 50 tonne return payload to Earth might be contained in ISS/Shuttle/Drago-type cargo bags and safely secured using some type of military-type strap-down system.  All of that gear could be carried to Mars collapsed and compressed.  Example:
...
...
Good idea. On Mars, just fill up packing bags with CO2.
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Offline Lar

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See also this thread entitled "Water, Methane, and Oxygen ISRU on Mars"

https://forum.nasaspaceflight.com/index.php?topic=40308
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Offline Ionmars

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See also this thread entitled "Water, Methane, and Oxygen ISRU on Mars"

https://forum.nasaspaceflight.com/index.php?topic=40308
Thanks, Lar.
To give an update, we are currently working on a sequel to the cargo modules paper. It is entitled "A Proposed BFS Greenhouse for an Initial Mars Base." Here we will suggest that an entrepreneur lease or purchase one of the super-sized  cargo modules and convert it into a multipurpose greenhouse. It would utilize well-tested growing techniques that are relatively easy to transport and set up on Mars.

 We have a review panel for the paper consisting of NSF members who participated in another forum "Scaling Agriculture for Mars." The panel has given the paper an early look-over, which led to an extensive rewrite. We should have something for you to look at by May. In the meantime, I an deep-diving into the work with occasional emergence for a breath of air.
« Last Edit: 02/05/2018 11:38 AM by Ionmars »
* Mars' orbit: a convenient service station for an asteroid-sized spaceship en-route to Ceres. *

Offline aero

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Has anyone considered or have there been orbital searches for crude oil on Mars?

Consider that some think that millions of years ago, Mars was a luxuriant planet with an atmosphere, plant life and all that entails. There are current theories about the origin of petroleum on Earth, and wouldn't those same theories apply to Mars?

 If oil were discovered deep under the Mars surface, it would give Mars bases chemical industry a real shot in the arm! Not to mention being a source of methane.

https://en.wikipedia.org/wiki/Mars
« Last Edit: 02/07/2018 06:01 PM by aero »
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Online AC in NC

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Has anyone considered or have there been orbital searches for crude oil on Mars?

Talk about wildcatting!!!   :o

Offline fortynineundefeated

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The purpose of the unhinged lower panel is to allow the entire heatshield side of the spaceship to be produced as one piece. When we proposed this as an option in the paper, we didn't know that SpaceX would want to develop this capability. Apparently they do.

The release of the vessel may be easier on Mars surface. We proposed a "vessel grappler" that could remove the vessel from the side. Also the half-fairing is a removable panel rather than hinged, so it is removed and set aside.

Edit: spelling

Sorry if this was answered elsewhere, but how would these grapplers or the crane in your paper be delivered to the surface?

Offline speedevil

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The purpose of the unhinged lower panel is to allow the entire heatshield side of the spaceship to be produced as one piece. When we proposed this as an option in the paper, we didn't know that SpaceX would want to develop this capability. Apparently they do.

What are you basing this on?
Just the pictures of the hinged 'fairing' of the cargo vehicle?

Offline Valerij

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From my point of view, the concept of the proposed cargo module has two very serious problems. The first is that the production of fuel on Mars must be deployed as quickly as possible, since it is necessary to return the ITS to Earth for the next flight. To allocate a large number of ITS ships exclusively for the delivery of modules of the fuel complex will be difficult. The second problem is that to start working with such a large cargo module it is necessary to have heavy and bulky equipment on Mars. At the initial stage of development of Mars, the availability of such equipment there is unrealistic.
   
According to the attached scheme, to ensure the flights of twelve ITS it is necessary to have a complex of twenty-eight cargo modules. And twenty-four of them are used exclusively for the storage of products and intermediate materials. And this does not include the necessary energy source and infrastructure for the construction and maintenance of the complex.
   

   
It seems to me that most of the elements of the fuel complex are better mounted on the Earth, under the fairing 2-3 copies of the ITS, leaving a passage in the middle. In the central pass, load a nuclear reactor on a cart, a universal transport and construction rover and materials for assembling a fuel complex. For their unloading a small crane, located above the entrance hatch, is necessary. As technological capacities of a fuel complex to use fuel and oxidizer tanks of these ITS, their other capacities.
   
Produced fuel can be directly loaded into the ITS, standing on the launch pad. To this end, next to each of them will need to place a small heat exchanger and supply them with a coolant. As a result, it will be possible to create a fuel complex on Mars in just 2-3 flights of ITS, while ensuring further development of the colony by the energy of the reactor and a small construction and transport infrastructure.

Offline Lar

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I don't see this "build a chemical industry" proposal as being how the first ISRU fuel is produced, but rather how to ramp up an industry once your (single load?) ISRU plant is producing fuel and oxidizer. The diagram you show is at a relatively late stage, and there is useful propellant produced well before that many loads are required.

Your organization certainly makes sense as a possible configuration for the first load pilot plant, though. Whether it's exactly right would be a matter of working the trades and trying to engineer it, but it struck me as not that far off.
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Offline Valerij

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The diagram you show is at a relatively late stage, and there is useful propellant produced well before that many loads are required.
So I'm talking about this. It seems to me that it would be justifiable to sacrifice two or three ITS at the first stage to build a complex for the production of fuel at the first stage. And there is no point in bringing to Mars 24 huge storage tanks for fuel storage while expanding this complex. The complex for the production of fuel simultaneously produces raw materials, from which it is possible to make fiberglass and carbon plastics. Using this material it becomes possible to build a building such as a huge hangar for an airship. And in this hangar, it will be possible to build both fuel storage tanks and other large modules necessary for the construction and maintenance of the colony.
   
Large reservoirs with effective thermal insulation will be a mass product for the Martian industry. Therefore it is necessary to learn as soon as possible how to do them locally, from local materials, and not to bring them from Earth.
   

Offline DaveH62

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Wouldn’t it be ironic if Musk started an oil and gas industry on Mars, while trying to replace it on earth.

Great thread. You guys are doing great stuff.

Offline Lar

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The diagram you show is at a relatively late stage, and there is useful propellant produced well before that many loads are required.
So I'm talking about this. It seems to me that it would be justifiable to sacrifice two or three ITS at the first stage to build a complex for the production of fuel at the first stage. And there is no point in bringing to Mars 24 huge storage tanks for fuel storage while expanding this complex. The complex for the production of fuel simultaneously produces raw materials, from which it is possible to make fiberglass and carbon plastics. Using this material it becomes possible to build a building such as a huge hangar for an airship. And in this hangar, it will be possible to build both fuel storage tanks and other large modules necessary for the construction and maintenance of the colony.
   
Large reservoirs with effective thermal insulation will be a mass product for the Martian industry. Therefore it is necessary to learn as soon as possible how to do them locally, from local materials, and not to bring them from Earth.
   

I think the very first plant has to be a single load. That means power, any mining or drilling equipment, any preconditioning, reactors, and in process storage, as well as pumps, plumbing, etc. all have to fit in the cargo hold of a single BFS. The BFS itself can be the tankage, yes.

This proposal is for later. Even 2 or 3 loads is later than what you send first. IMHO.
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Online rakaydos

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The diagram you show is at a relatively late stage, and there is useful propellant produced well before that many loads are required.
So I'm talking about this. It seems to me that it would be justifiable to sacrifice two or three ITS at the first stage to build a complex for the production of fuel at the first stage. And there is no point in bringing to Mars 24 huge storage tanks for fuel storage while expanding this complex. The complex for the production of fuel simultaneously produces raw materials, from which it is possible to make fiberglass and carbon plastics. Using this material it becomes possible to build a building such as a huge hangar for an airship. And in this hangar, it will be possible to build both fuel storage tanks and other large modules necessary for the construction and maintenance of the colony.
   
Large reservoirs with effective thermal insulation will be a mass product for the Martian industry. Therefore it is necessary to learn as soon as possible how to do them locally, from local materials, and not to bring them from Earth.
   

I think the very first plant has to be a single load. That means power, any mining or drilling equipment, any preconditioning, reactors, and in process storage, as well as pumps, plumbing, etc. all have to fit in the cargo hold of a single BFS. The BFS itself can be the tankage, yes.

This proposal is for later. Even 2 or 3 loads is later than what you send first. IMHO.
If they think they can get decent landing accuracy, I could see having the mining/drilling bots, and piping in the second bfs, where they can unload and use it as extra tanks, but have all the fuelmaking equipment in the first ship.

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Since a major part of your plan is "wasting" upper stages on storage modules, would it be possible to use some kind of balloon arrangement? Instead of 24 essentially empty storage tanks, fill a ship with 50t of high tensile strength balloons and inflate them with the necessary gasses on mars. Maximum pressure for space efficiency isn't exactly an issue when you have the entire planet for yourself. Also, you could probably cut down on final product tanks and use the rocket itself for some. It's unlikely, at least in the short term, that a rocket would land and immediately take off again. As for longer term storage solutions, plastic tanks can be produced locally and even buried to enable liquefied storage without worrying about heat from the sun.

EDIT: Quick back of the envelope calculation shows that a 10m radius sphere stores about 6t of oxygen per bar of pressure at 0°. A single layer of mylar that size weighs just 12.5kg. A typical plastic at 1g/cm² and 1mm thickness would weigh 1250kg.
« Last Edit: 02/20/2018 11:11 AM by niwax »

Offline biosehnsucht

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To add onto the idea of inflatable / pop up tanks : you could probably build some kind of folded frame that unfolds / extends along with the tank to provide a bit more stability than the tank itself would have. It might significantly increase mass for the tank, but the starting mass is pretty low so it's probably not a big deal.

The hard part would be the mechanism for deploying / placing these since you can't simply just inflate them where they sit...

Well maybe you could a few. BFS lands, jaw pops open, you've got about half the payload volume exposed, so you could expand some inflatable tanks from the sides in a couple of places ...

However I think that inflatable tanks without some kind of Bigelow style protective layers might be a bad idea since it would be pretty high risk to chance not having any micrometeorites puncture them. Though even just having a fold out roof above the inflated tank would probably work fine, chances of damage from sideways seem pretty low.

Offline niwax

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Once there are humans there able to build larger infrastructure, protection becomes fairly simple. Dig a hole big enough to drop the bottom half in, cover up the top half with a sheet of plastic, possibly even made in-situ. Should reduce stresses on the tank significantly too.

Spherical gas tanks on earth are often just placed in a cradle, that could be an option. Build a four-armed foldable cradle with the deflated tank in the middle and valves at the center. Drop it and unfold, the balloon the expands to fill out the cradle.

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