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#1 2006-11-04 14:08:55

jjcmarsh7
Member
From: Boston, MA
Registered: 2006-11-04
Posts: 1

Re: Thermal Depolymerization / thermal conversion process

Prompt:

Could this be the next closest step to "ultimate recycling" onboard a mars bound manned space mission?

Wikipedia description:

Technology Sketch:

Changing World Technologies (CWT)

Private Company founded in August 1997 by Brian S. Appel
Purpose: to develop and commercialize the "thermal depolymerization" technology AKA "thermal conversion process"

Thermal depolymerization (TDP) is a process for the reduction of complex organic materials (usually waste products of various sorts, often known as biomass and plastic) into light crude oil. It mimics the natural geological processes thought to be involved in the production of fossil fuels. Under pressure and heat, long chain polymers of hydrogen, oxygen, and carbon decompose into short-chain petroleum hydrocarbons with a maximum length of around 18 carbons.

Link: http://en.wikipedia.org/wiki/Thermal_depolymerization
http://www.mindfully.org/Energy/2003/An … 1may03.htm

Questions:

1.  Will this process kill microbacteria living in the waste products onboard the life support module?

2.  Could a proof of concept closed system be created with wastes being directed to the depolymer device and products from that device being redirected into fuel containers, water reverse-osmosis for drinking, and carbon solids containers?

3.  Investigate how the output of such a device could be further used on a life support system onboard a spacecraft.

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#2 2006-11-04 14:14:37

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Thermal Depolymerization / thermal conversion process

Trouble is there isn't much need for crude oil on a space ship.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#3 2006-11-04 14:39:24

cIclops
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Registered: 2005-06-16
Posts: 3,230

Re: Thermal Depolymerization / thermal conversion process

Trouble is there isn't much need for crude oil on a space ship.

Perhaps it could be refined into Kerosene for rocket fuel smile


Let's go to Mars and far beyond -  triple NASA's budget !   #space channel !!    - videos !!!

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#4 2006-11-04 15:54:55

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,162
Website

Re: Thermal Depolymerization / thermal conversion process

It's a useful technique to recycle plastic. Many forms of plastic can be melted and moulded to make new parts, but once it's undergone polymer scission and cross-linked from UV exposure, it's pretty useless. That turns plastic into yellow, brittle stuff. This process can break down ruined plastic to make oil that can be used to make new plastic, or fuel, or lubricating oil, or any other use for oil.

A local guy is building a pyrolysis device to use the same principle, but rather than capturing oil and gas he intends to burn everything. It'll be a high-tech incinerator, able to destroy BSE or West Nile Virus infected carcasses.

This is useful on Earth, but completely useless on a spacecraft. It requires a lot of energy, and that comes form burning some of the oil and gas produced. It consumes oxygen, but a spacecraft has to recycle all its oxygen. The heat produced has to be eliminated with each cycle, a lot of energy lost. A spacecraft has excess heat from human bodies and electronics, it requires an active cooling system as it is.

Look, let me put it simply. In a sealed environment where you have to recycle oxygen, you can't afford to burn anything. Thermal depolymerization is a fancy furnace.

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#5 2006-11-04 16:30:51

Ian Flint
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From: Colorado
Registered: 2003-09-24
Posts: 437

Re: Thermal Depolymerization / thermal conversion process

You forgot the last option:

3) No!  Definitely not!

I admit I haven't researched the process much, but it seems a bit too energy intensive and gives little immediate returns for a mere manned mission.  Including it in a colonization effort makes more sense.  I'd add a test model sometime after mission 3.

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#6 2006-11-05 13:37:22

neviden
Member
Registered: 2004-05-06
Posts: 99

Re: Thermal Depolymerization / thermal conversion process

oil is useless in space for burning, but we use oil on earth to make plastics.. once you have plastic feedstock, you can use rapid prototyping machine to make plastic parts..

http://en.wikipedia.org/wiki/3D_printing
http://en.wikipedia.org/wiki/Rapid_prototyping

and since you can use trash/organic material/broken plastics/human and especialy organic waste (waste from growing food) there is enough of it to make it usefull (to get more oil just grow more food).. maybe for spare parts at first (important because the first shop is millions of miles away), later means of self sufficiency /reduced resuply costs from earth..

how soon this would be used in space depends of course on how big all of this would get and how advanced 3D printing will be.. first missions will probably not have this, but this could be very usefull to have in any premanent base.. (we will see this on moon first i guess)

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#7 2006-11-05 14:46:58

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Thermal Depolymerization / thermal conversion process

Please note that not all oils are created equal, and it also takes quite a bit of chemistry to go from raw alkanes to anything besides simple polyethylene or polypropylene.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#8 2006-11-05 15:17:11

C M Edwards
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From: Lake Charles LA USA
Registered: 2002-04-29
Posts: 1,011

Re: Thermal Depolymerization / thermal conversion process

IMHO, there's nothing wrong with polypropylene and polyethylene.  However, we don't need thermal depolymerization products to make those.  The equipment for making these plastics can be sent with the first missions, and is both simpler and a lot less energy intensive than the process suggested.

True, actual breakdown products in thermal depolymerization of complex organic materials can be distilled for more than just diesel oil and can be used to make other plastics.  It offers a good means of recycling, too, but only if you have a lot of feedstock.  An entire colony of 30 or more people might (might) go through enough material each day to make the process worthwhile.  A half dozen prospectors staying a year or less would have no need of it, though.

So, the desirability of this type of recycling depends on how many people intend to live at the base.  It's simply not worth the effort for less than 30 to 60 people.

Since I'm all in favor of bases with 60+ crew size, I'm happy to vote "Yes" for this idea.  Don't settle for LDPE - go for Kevlar and Viton.


"We go big, or we don't go."  - GCNRevenger

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#9 2006-11-05 19:26:16

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Thermal Depolymerization / thermal conversion process

Kevlar is hard enough to make on Earth, might want to focus on something simpler, like Polyethylene terephtalate  (PET) or Polytrimethylene terephtalate (PTT) for inflatables and textiles/carpet, butyl rubbers for O-rings or pressure bladders, that sort of thing. Viton and Teflon unfortunately require Fluorine and Polyvinylchoride (PVC) needs Chlorine which isn't readily available on Mars or the Moon.

Spectra fiber is a special superhigh grade polyethylene that might handy... inflatable modules reinforced by Spectra or something perhaps.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#10 2006-11-05 22:02:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,721

Re: Thermal Depolymerization / thermal conversion process

So I take it that you rember not any of this:

SpaceNut
Pioneer Member
Joined: 22 Jul 2004
Total posts: 4543
Location: New Hampshire
Gender: Unknown Posted: Sat Sep 23, 2006 6:56 pm    Post subject:       

--------------------------------------------------------------------------------

GCNRevenger wrote:

spacenut wrote:

It needs to have a complement of manufacturing capability to at least turn what would be garbage into useful items in order to make it grow in size, maybe repair or create shielding and to salvage junk for other uses. 

No, because the garbage isn't worth much. The trouble of reprocessing it into useful materials is so difficult that it would be much easier just to launch new stuff. 


Whats one of the items we are constantly needing for the station, you guessed it rocket fuel to reboost it.

You may recall this: Bacteria Eat Human Sewage, Produce Rocket Fuel

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RobertDyck
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Joined: 20 Aug 2002
Total posts: 1642
Gender: Unknown Posted: Sun Sep 24, 2006 12:11 am    Post subject:       

--------------------------------------------------------------------------------

SpaceNut wrote:
Whats one of the items we are constantly needing for the station, you guessed it rocket fuel to reboost it.

You may recall this: Bacteria Eat Human Sewage, Produce Rocket Fuel

From that same article:Quote:
But don't expect the bacteria to supply NASA with rocket fuel to launch a spacecraft.

"It costs [the bacteria] a lot of energy, and they get return on their investment by consuming it again," Strous explained. "They are dependent on it, so it can't be removed."

From WikipediaQuote:
Methanogenesis or 'biomethanation' is the formation of methane by microbes. This is an important and widespread form of microbial metabolism. In most environments, it is the final step in the decomposition of organic matter.

The two best described pathways involve the use of carbon dioxide and acetic acid as terminal electron acceptors:

This means you can use normal anaerobic bacteria in a digester. To burn methane in rocket engines, you'll need oxygen. You can split  to recover oxygen, direct  electrolysis will only convert 80% into CO and oxygen so you'll need something better. A little hydrogen in RWGS can convert  into water and carbon soot, then split water with water electrolysis. Use the oxygen for rocket fuel, recycle the hydrogen. Even if the process is 100% efficient, it'll only produce 1 molecule of oxygen for every molecule of methane. Burning  requires 2 molecules of  to produce 1  and 2 . You're short oxygen, and the equipment is complex. Is it worth it?

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SpaceNut
Pioneer Member
Joined: 22 Jul 2004
Total posts: 4543
Location: New Hampshire
Gender: Unknown Posted: Sun Sep 24, 2006 5:45 pm    Post subject:       

--------------------------------------------------------------------------------

Researchers Find New Pathway To Making Methane

Quote:
Developed by Berndt and Juske Horita of the chemical and analytical sciences division of Oak Ridge National Laboratory, the new process produces methane from bicarbonate ions and hydrogen at temperatures up to 400 degrees C. The catalyst for the conversion was an iron-nickel alloy found in certain parts of the oceanic crust. Berndt said the methane produced was chemically difficult to distinguish from organically produced methane. 


Ceramic Microreactors Developed For On-Site Hydrogen Production

Quote:
reforming of hydrocarbon fuels, such as propane, into hydrogen for use in fuel cells and other portable power sources. When reforming hydrocarbons such as propane, temperatures above 800 degrees Celsius prevent the formation of soot that can foul the catalyst surface and reduce performance.


At this point the Elektron system once the oxygen is removed from the waste water is expelled out of the station as being of no value.

There may even be other ways of doing this.

The other materials being plastic can be used on the moon for making steel if they were sent to its surface. We have a thread I think under technology for this as I recall.

While the expense may not be justifiable getting to technology to advance makes the effort to prove them and to use them as intended allows for a continual progress towards one day having it ready for Mars.

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#11 2006-11-06 08:53:30

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Thermal Depolymerization / thermal conversion process

Why would you bother with steel on the Moon? The surface is littered with aluminum ore. In fact, raw low-grade aluminum may well be a waste byproduct of oxygen production.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#12 2006-11-06 10:16:15

dicktice
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From: Nova Scotia, Canada
Registered: 2002-11-01
Posts: 1,764

Re: Thermal Depolymerization / thermal conversion process

I wonder what will be found on the Moon, when we have the capability to do deep drilling straight down towards the centre?

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#13 2006-11-06 10:46:44

C M Edwards
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From: Lake Charles LA USA
Registered: 2002-04-29
Posts: 1,011

Re: Thermal Depolymerization / thermal conversion process

Why would you bother with steel on the Moon?

The same reason you bother with it on Earth - it's tough as nails, strong as hell, and (if you're able to do real metallurgy with it and not just turn out a few low grade castings) you can use it in almost anything.  For any aluminum alloy you can come up with, there's usually a better steel alloy for the same application. 

That's why you bother with steel.

Aluminum has only two advantages over steel: it's lighter, and it's easier to melt.  If you're not going to fly your moonbase, use steel instead of aluminum.


"We go big, or we don't go."  - GCNRevenger

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#14 2006-11-06 13:04:52

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Thermal Depolymerization / thermal conversion process

Yes for specialty things like nuclear reactor parts, rover axles, and mining drills steel is the obvious choice. But the ready availability of aluminum, literally just piling up, and the ease of forging make it the obvious choice for general purpose construction. Steel manufacture also requires carbon, which is in very short supply, steel is the obvious wrong choice for bulk structural material.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

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#15 2006-11-06 13:54:42

Grypd
Member
From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,862

Re: Thermal Depolymerization / thermal conversion process

Still there is also the mineral Ilmenite which will give you Titanium if you need stronger alloyed parts. Certainly we will have a lot on hand as we will be looking for ilmenite so that we can extract the oxygen from it.

Titanium combined with Aluminium should make decent strength alloyed components. And there is also the iron from it too though less in quantity.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#16 2006-11-06 18:44:58

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,162
Website

Re: Thermal Depolymerization / thermal conversion process

There is chlorine on the Moon and Mars. The Moon may not have much, but Mars soil is quite salty.
The Apollo and Luna Samples
Chemistry of Mars Pathfinder Samples Determined by the APXS

Since everything else appears to be on Mars, now we need to prospect for fluorine mineral. Teflon, PCTFE, and Goretex (expanded PTFE) would be really, really, good in the cold on Mars.

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#17 2006-11-06 21:14:29

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,721

Re: Thermal Depolymerization / thermal conversion process

Other uses for plastic on the moon or for mars.
Mars ship Needs Radiation shielding just another reason to not throw out everything that we would label as garbage when it can be just what we need to expand.

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#18 2006-11-07 08:32:25

C M Edwards
Member
From: Lake Charles LA USA
Registered: 2002-04-29
Posts: 1,011

Re: Thermal Depolymerization / thermal conversion process

Mars ship Needs Radiation shielding just another reason to not throw out everything that we would label as garbage when it can be just what we need to expand.

Perhaps the lowly bagworm might be a biomechanical model for a mars mission spacecraft.

Does anyone have any figures for how much garbage the ISS ejected and/or sent back to Earth last year, including liquid wastes?

If this approach to radiation shielding is practical, thermal depolymerization may yet be useful for first missions.

Hmm...


"We go big, or we don't go."  - GCNRevenger

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#19 2007-01-13 18:25:29

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,721

Re: Thermal Depolymerization / thermal conversion process

Its funny how we want to have earth on mars even to the point of creating grand processes of simular scale.

Polymer Synthesis & Manufacturing Systems

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#20 2007-01-13 20:30:32

C M Edwards
Member
From: Lake Charles LA USA
Registered: 2002-04-29
Posts: 1,011

Re: Thermal Depolymerization / thermal conversion process

Its funny how we want to have earth on mars even to the point of creating grand processes of simular scale.

Polymer Synthesis & Manufacturing Systems

What's wrong with that?  wink


"We go big, or we don't go."  - GCNRevenger

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