Generating Air / Oxygen

[Chris Holmes]

Hi All,

I am thinking about building s space station….

How would I go about generating breathable air.

Or eould you recommend regular deliveries of oxogen / air?

[Pancho]

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

The ISS uses magnet monopoles to create a magnet funnel, which can scoop
up the extremely rarefied oxygen that exists in near earth orbit. This
is similar to the idea of a Bussard ramjet, but obviously less
sophisticated.

No deliveries of oxygen are required.

[Sam Plusnet]

Post by Pancho

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

The ISS uses magnet monopoles to create a magnet funnel, which can scoop
up the extremely rarefied oxygen that exists in near earth orbit. This
is similar to the idea of a Bussard ramjet, but obviously less
sophisticated.
No deliveries of oxygen are required.

Get it delivered, and then auction off the supplies to the highest
bidder amongst the on-board crew. It could be a profitable venture.

[Adrian Caspersz]

Post by Sam Plusnet

Post by Pancho
The ISS uses magnet monopoles to create a magnet funnel, which can
scoop up the extremely rarefied oxygen that exists in near earth
orbit. This is similar to the idea of a Bussard ramjet, but obviously
less sophisticated.
No deliveries of oxygen are required.

Get it delivered, and then auction off the supplies to the highest
bidder amongst the on-board crew.  It could be a profitable venture.

Amazon. Then tax it.

[Roger Mills]

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

I think that would be the least of your worries!

[ChatGPT]

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Building a space station presents a huge challenge in sustaining a
breathable atmosphere. You have two main approaches: closed-loop air
recycling and regular resupply missions. A combination of both is
typically the most practical.

1. Methods for Generating and Recycling Breathable Air
A space station must maintain a mix of approximately 21% oxygen and 78%
nitrogen at 1 atmosphere (14.7 psi) or lower for human comfort. Here’s
how you can generate and recycle breathable air:

A. Oxygen Generation

1. Electrolysis of Water (Primary Method)
- Uses electricity (usually from solar panels) to split H2O into O2 and H2.
- The O2 is released into the crew cabin.
- The H2 is usually vented into space or used in a Sabatier reaction
(see below).
- Example: NASA’s Oxygen Generation Assembly (OGA) on the ISS.

2. Chemical Oxygen Candles (Backup)
- Solid oxygen generators like "chlorate candles" or "peroxide-based
candles".
- Used as emergency oxygen sources.
- Example: Vika system on Russian spacecraft.

3. Stored or Delivered Oxygen (Backup)
- Oxygen tanks or liquid oxygen can be periodically resupplied.
- This is not sustainable for long-term missions but serves as a backup.

B. Carbon Dioxide Removal

Exhaled air contains CO2, which must be removed to avoid poisoning the
crew. Several methods exist:

1. Lithium Hydroxide (LiOH) Scrubbers (Consumable)
- Absorbs CO2 chemically.
- Used in spacecraft like Apollo and early ISS modules.
- Not regenerable, so it requires constant replacement.

2. Molecular Sieve CO2 Scrubbers (Regenerable)
- Uses zeolite materials to absorb CO2, which is later vented into space.
- Example: ISS’s Carbon Dioxide Removal Assembly (CDRA).

3. Sabatier Reaction (Best for Long-Term Missions)
- Reacts carbon dioxide (CO2) with hydrogen (H2) to produce methane
(CH4) and water (H2O).
- The water is recycled into the electrolysis system to generate more
oxygen.
- Reduces waste and increases efficiency.
- Example: ISS Sabatier System.
- Reaction: CO2 + 4H2 -> CH4 + 2H2O

4. Algae or Plants (Experimental)
- Algae (like Chlorella) or plants can absorb CO2 and produce O2 through
photosynthesis.
- NASA has tested plant-based life support, but it requires significant
space and light.
- Might be useful for long-term deep-space habitats.

[Andy Burns]

Post by Chris Holmes
I am thinking about building s space station….
How would I go about generating breathable air.

If you suck-up to Putin, maybe he has a couple of warehouses full of
new-old-stock oxygen candles he'll let you have?

[John Rumm]

Post by Andy Burns

Post by Chris Holmes
I am thinking about building s space station….
How would I go about generating breathable air.

If you suck-up to Putin, maybe he has a couple of warehouses full of
new-old-stock oxygen candles he'll let you have?

You will have to prize the orange oaf off his butt hole first!
--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[Chris Holmes]

Post by John Rumm

Post by Andy Burns

Post by Chris Holmes
I am thinking about building s space station….
How would I go about generating breathable air.

If you suck-up to Putin, maybe he has a couple of warehouses full of
new-old-stock oxygen candles he'll let you have?

You will have to prize the orange oaf off his butt hole first!

ROTFLMAO!!

[fred]

Post by Chris Holmes
Hi All,
I am thinking about building s space station
.
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

The kids did this recently in the back garden, the difficulty was getting
the cardboard boxes from the supermarket before they were crushed.
Oxygenated air appeared to be readily available, perhaps being filtered
along the length of the corrugations.

[Bernard Peek]

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

There are plenty of icy comets that occasionally get kicked out of the Oort
cloud. You can use either electrolysis or photolysis to get the oxygen out.

[N_Cook]

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

more a Q for uk.rec.gardening

ala film Silent Running

[TimW]

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.

TW

[Jim the Geordie]

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.
TW

I think fighter-pilots sometimes use pure oxygen. It makes no difference
to speech.
I had access to a bottle at work, and it's great for clearing your head
after a night on the town. :)

[SteveW]

Post by Jim the Geordie

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.
TW

I think fighter-pilots sometimes use pure oxygen. It makes no difference
to speech.
I had access to a bottle at work, and it's great for clearing your head
after a night on the town. :)

Back in the '80s, our deputy-headmaster/chemistry teacher, used to
breath the Oxygen from the bottle at the front of the lab, during
lessons. He did have an alcohol problem and took some months off drying out.

[Tim+]

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen?

Until one caught fire on the launch pad…

Post by TimW
I was trying
to imagine what that would be like to breathe and to speak.

You probably wouldn’t notice any difference. It’s not helium…

Tim

[Max Demian]

Post by Tim+

Post by TimW

Post by Chris Holmes
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen?

Until one caught fire on the launch pad…

That's because it was at 20 psi to simulate the condition in space when
it would be at 5 psi. Almost anything will burn in oxygen at that pressure.

[Tim Streater]

Post by TimW

Post by Chris Holmes
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.

Not after Apollo 1 they didn't.

[Chris Hogg]

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.
TW

Yes, they did. It accelerated the combustion of the flammable contents
of the first Apollo space capsule in 1967 and resulted in the deaths
of three astronauts during a practice run.
https://tinyurl.com/3y75dh28

I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen. Oxygen does not have such a big difference in
molecular weight from air (or rather the mixture of oxygen and
nitrogen that constitutes air), compared with the difference in
molecular weight between hydrogen and air, which is responsible for
the difference in the velocity of sound through the two gases, and
hence the 'squeaky voice' effect. Sound travels roughly three times
faster in hydrogen than in air, bit its speed in oxygen is virtually
the same as in air.

Velocities of sound in various gases:
Air 331m/sec.
Oxygen 330m/sec.
Helium 973m/sec.

https://www.engineeringtoolbox.com/speed-sound-gases-d_1160.html

[jon]

Post by Chris Hogg

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.
TW

Yes, they did. It accelerated the combustion of the flammable contents
of the first Apollo space capsule in 1967 and resulted in the deaths of
three astronauts during a practice run. https://tinyurl.com/3y75dh28
I doubt if they had the 'squeaky voices' of those of us who played with
inhaling hydrogen. Oxygen does not have such a big difference in
molecular weight from air (or rather the mixture of oxygen and nitrogen
that constitutes air), compared with the difference in molecular weight
between hydrogen and air, which is responsible for the difference in the
velocity of sound through the two gases, and hence the 'squeaky voice'
effect. Sound travels roughly three times faster in hydrogen than in
air, bit its speed in oxygen is virtually the same as in air.
Air 331m/sec.
Oxygen 330m/sec.
Helium 973m/sec.
https://www.engineeringtoolbox.com/speed-sound-gases-d_1160.html

Inhaling Helium a noble gas.

[Tim+]

Post by Chris Hogg

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.
TW

Yes, they did. It accelerated the combustion of the flammable contents
of the first Apollo space capsule in 1967 and resulted in the deaths
of three astronauts during a practice run.
https://tinyurl.com/3y75dh28
I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen.

Hydrogen? Don’t you mean helium? Certainly much easier for Joe Public to
get hold of.

Tim

[Chris Hogg]

Post by Chris Hogg

Post by TimW

Post by Chris Holmes
Hi All,
I am thinking about building s space station?.
How would I go about generating breathable air.
Or eould you recommend regular deliveries of oxogen / air?

Didn't early spaceships use an atmosphere of pure Oxygen? I was trying
to imagine what that would be like to breathe and to speak.
TW

Yes, they did. It accelerated the combustion of the flammable contents
of the first Apollo space capsule in 1967 and resulted in the deaths
of three astronauts during a practice run.
https://tinyurl.com/3y75dh28
I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen.

Hydrogen? Don’t you mean helium? Certainly much easier for Joe Public to
get hold of.
Tim

Well, I did mean hydrogen, as we had a cylinder of it in the uni
chemistry lab that was a source of post-examinations stress relief and
fun. But the effect and 'squeaky voice' with helium would be much the
same as with hydrogen, and safer, too. Less likely blow yourself up! .

[Jeff Layman]

Post by Chris Hogg

Post by Tim+

Post by Chris Hogg
I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen.

Hydrogen? Don’t you mean helium? Certainly much easier for Joe Public to
get hold of.
Tim

Well, I did mean hydrogen, as we had a cylinder of it in the uni
chemistry lab that was a source of post-examinations stress relief and
fun. But the effect and 'squeaky voice' with helium would be much the
same as with hydrogen, and safer, too. Less likely blow yourself up! .

I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and getting
a deep voice!

[Andy Burns]

Post by Jeff Layman
I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and getting
a deep voice!

I think the goto gas for a deep voice is sulphur hexafluoride?

[Max Demian]

Post by Andy Burns

Post by Jeff Layman
I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and
getting a deep voice!

I think the goto gas for a deep voice is sulphur hexafluoride?

That's the one. Either way you've got to breathe air (or at least
oxygen) at the same time or you just stop breathing, pass out and
probably die. The same with nitrous oxide, which is why they call the
stuff that paramedics use "gas and air". (Actually I think it's nitrous
oxide and oxygen - I don't know whether the operators can adjust the ratio.)

This is because it's the presence of carbon dioxide in the lungs which
stimulates breathing, not the absence of oxygen.

[Bob Eager]

Post by Max Demian

Post by Andy Burns

Post by Jeff Layman
I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and
getting a deep voice!

I think the goto gas for a deep voice is sulphur hexafluoride?

That's the one. Either way you've got to breathe air (or at least
oxygen) at the same time or you just stop breathing, pass out and
probably die. The same with nitrous oxide, which is why they call the
stuff that paramedics use "gas and air". (Actually I think it's nitrous
oxide and oxygen - I don't know whether the operators can adjust the ratio.)
This is because it's the presence of carbon dioxide in the lungs which
stimulates breathing, not the absence of oxygen.

I understand that helium is a preferred method of suicide. Small cylinder,
tube, bag over head.

[Bernard Peek]

Post by Jeff Layman

Post by Chris Hogg

Post by Tim+

Post by Chris Hogg
I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen.

Hydrogen? Don’t you mean helium? Certainly much easier for Joe Public to
get hold of.
Tim

Well, I did mean hydrogen, as we had a cylinder of it in the uni
chemistry lab that was a source of post-examinations stress relief and
fun. But the effect and 'squeaky voice' with helium would be much the
same as with hydrogen, and safer, too. Less likely blow yourself up! .

I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and getting
a deep voice!

There should be lots of reports of people breathing Xenon. It's used as an
anaesthetic gas.

[Tim+]

Post by Bernard Peek

Post by Jeff Layman

Post by Chris Hogg

Post by Tim+

Post by Chris Hogg
I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen.

Hydrogen? Don’t you mean helium? Certainly much easier for Joe Public to
get hold of.
Tim

Well, I did mean hydrogen, as we had a cylinder of it in the uni
chemistry lab that was a source of post-examinations stress relief and
fun. But the effect and 'squeaky voice' with helium would be much the
same as with hydrogen, and safer, too. Less likely blow yourself up! .

I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and getting
a deep voice!

There should be lots of reports of people breathing Xenon. It's used as an
anaesthetic gas.

Um, where/when? It’s been a few years since I last gave an anaesthetic but
xenon was never on the menu.

A quick search shows that it has been trialed/used but has a very high
incidence of post-op nausea and vomiting. I imaging the number of
hospitals with xenon supplies is vanishingly small.

Tim

[Thomas Prufer]

Post by Jeff Layman

Post by Chris Hogg

Post by Tim+

Post by Chris Hogg
I doubt if they had the 'squeaky voices' of those of us who played
with inhaling hydrogen.

Hydrogen? Don’t you mean helium? Certainly much easier for Joe Public to
get hold of.
Tim

Well, I did mean hydrogen, as we had a cylinder of it in the uni
chemistry lab that was a source of post-examinations stress relief and
fun. But the effect and 'squeaky voice' with helium would be much the
same as with hydrogen, and safer, too. Less likely blow yourself up! .

I reckon many people have tried breathing helium and got a squeaky
voice. I've never heard, however, of anyone breathing xenon and getting
a deep voice!

I have tried it the other way round. No, not that way, but blowing helium in one
ear canal. Very odd experience. I think that the difference in the speed of
sounds shifts the acoustically perceived source of sound to the side of the seen
source of sound. So someone talking will be heard off to their side.


Thomas Prufer

[Scott]

On Thu, 6 Mar 2025 12:49:24 -0000 (UTC), Chris Holmes

Post by Chris Holmes
Hi All,
I am thinking about building s space station….
How would I go about generating breathable air.
Or would you recommend regular deliveries of oxogen / air?

I would like to generate it here on earth, at scale, to dilute the
carbon dioxide in the atmosphere.

[Tim Streater]

Post by Scott
On Thu, 6 Mar 2025 12:49:24 -0000 (UTC), Chris Holmes

Post by Chris Holmes
Hi All,
I am thinking about building s space station

.

Post by Scott

Post by Chris Holmes
How would I go about generating breathable air.
Or would you recommend regular deliveries of oxogen / air?

I would like to generate it here on earth, at scale, to dilute the
carbon dioxide in the atmosphere.

Then you'll be diluting the nitrogen, too. And once the O2 content is
increased to more than 35% or so, due to your O2 generation activities, the
shit will hit the fan - namely, wet wood and wet vegetation will burn nicely
and you'll have fires all over the planet.

NB - that wouldn't be the first time in the Earth's history that O2 will have
been at 35%. It will crank up the CO2 levels, nicely, too, to historical
levels.

[Tim Streater]

Post by Scott
On Thu, 6 Mar 2025 12:49:24 -0000 (UTC), Chris Holmes

Post by Chris Holmes
Hi All,
I am thinking about building s space station

.

Post by Scott

Post by Chris Holmes
How would I go about generating breathable air.
Or would you recommend regular deliveries of oxogen / air?

I would like to generate it here on earth, at scale, to dilute the
carbon dioxide in the atmosphere.

Furthermore, once the O2 content reaches some level (dunno what, but this
certainly applies to 100% O2 at atmos pressure), breathing it will cause
serious lung damage.

[Sam Plusnet]

Post by Tim Streater

Post by Scott
On Thu, 6 Mar 2025 12:49:24 -0000 (UTC), Chris Holmes

Post by Chris Holmes
Hi All,
I am thinking about building s space station

.

Post by Scott

Post by Chris Holmes
How would I go about generating breathable air.
Or would you recommend regular deliveries of oxogen / air?

I would like to generate it here on earth, at scale, to dilute the
carbon dioxide in the atmosphere.

Furthermore, once the O2 content reaches some level (dunno what, but this
certainly applies to 100% O2 at atmos pressure), breathing it will cause
serious lung damage.

Not breathing is also a health hazard.
You can't win.

[Paul]

Post by Sam Plusnet

Post by Tim Streater

Post by Scott
On Thu, 6 Mar 2025 12:49:24 -0000 (UTC), Chris Holmes

Post by Chris Holmes
Hi All,
I am thinking about building s space station

.

Post by Scott

Post by Chris Holmes
How would I go about generating breathable air.
Or would you recommend regular deliveries of oxogen / air?

I would like to generate it here on earth, at scale, to dilute the
carbon dioxide in the atmosphere.

Furthermore, once the O2 content reaches some level (dunno what, but this
certainly applies to 100% O2 at atmos pressure), breathing it will cause
serious lung damage.

Not breathing is also a health hazard.
You can't win.

Not always.

https://www.cbc.ca/radio/thecurrent/lemons-diving-survival-story-1.7487922

Paul