31–40 of 48 posts
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That feels super dangerous. CO2 is mostly fine to breathe, but it triggers the impulse to breathe. Without it you won't feel that you're running out of oxygen.
With real-time detection (I'd expect that exists, but don't know for sure) you can divert some of the airstream through this scrubber to target a particular concentration of CO2.
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That's CO2 IN the blood that "triggers breathing". Unless you plan to inject the powder, that's not really an issue.
What I mean is that scrubbing the CO2 leaves you in a scenario where the air is just as dangerous as before (no oxygen) but you don't have any reflexes or senses letting you know of the danger.
So it acts like a reusable CO2 trap, then releases said CO2 at the cost of heating it up to 140F. Which then releases it. It doesn't really talk about how you would sequester the gaseous CO2 other than "put it underground."... But if you put a gas underground it will eventually leak out. Even a liquid is prone to leak out eventually due to plate techtonics, but a liquid doesn't immediately turn into gaseous CO2. So t…
The other day I was wondering how people always talk about sending undesirable material (garbage, spent radioactive fuel, etc.) on a one way trip to the sun. Why not send things to the surface of Venus? It has an ultra dense atmosphere that pulverizes anything that reaches the surface. In the case of this material, it's just more C02, which is what the atmosphere of Venus is already primarily composed of. We aren't going to ever explore the surface of Venus, or at least we won't for thousands, if not millions of years, barring we can easily convert co2 into energy, so is this a bad idea?
So it acts like a reusable CO2 trap, then releases said CO2 at the cost of heating it up to 140F. Which then releases it. It doesn't really talk about how you would sequester the gaseous CO2 other than "put it underground."... But if you put a gas underground it will eventually leak out. Even a liquid is prone to leak out eventually due to plate techtonics, but a liquid doesn't immediately turn into gaseous CO2. So t…
What I'm about to say may sound absurd and an attempt to be funny, but I'm being serious. The other day I was wondering how people always talk about sending undesirable material (garbage, spent radioactive fuel, etc.) on a one way trip to the sun. Why not send things to the surface of Venus? It has an ultra dense atmosphere that pulverizes anything that reaches the surface. In the case of this material, it's just mor…
35 billion metric tons.
What's your back of the envelope energy figure for extracting that weight of a gas from the atmosphere, pressurising it, and lifting it to orbit and sending it to Venus?
Got a rough notion of the number of trips, fuel and resources that would need every single year?
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This is definitely a real problem, but it's not caused by higher outdoor CO2 levels. The levels outside are typically in the 400-500ppm range. When you're enclosed with not enough ventilation, the issue is you (and other breathing organisms) and the lack of ventilation, not the outdoor level. The outdoor level has absolutely risen, it's just not the important factor here. You're very lucky that you can keep windows o…
I disagree- many people, especially in Europe are still using buildings designed in pre-industrial times, when CO2 levels were as low as half what they are in urban areas now. Those buildings now will have much higher CO2 levels indoors than when first built, with the same amount of air exchange. One could estimate exactly how much higher with some differential equations, but certainly in some cases it is possible to…
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You produce the CO2 that causes the impulse to breathe. That's what you are exhaling.
Right, and you want that. Scrubbing the CO2 without adding oxygen leaves you in a state where the air is useless and your body can't tell.
Earlier quoted context omitted.
That's CO2 IN the blood that "triggers breathing". Unless you plan to inject the powder, that's not really an issue.
What I mean is that scrubbing the CO2 leaves you in a scenario where the air is just as dangerous as before (no oxygen) but you don't have any reflexes or senses letting you know of the danger.
Earlier quoted context omitted.
You produce the CO2 that causes the impulse to breathe. That's what you are exhaling.
Right, and you want that. Scrubbing the CO2 without adding oxygen leaves you in a state where the air is useless and your body can't tell.
If you go into an area with no oxygen, you will pass out very quickly with little warning except being dizzy, but you will not fail to feel like you need to breathe.
It might be slightly more safe to enter into a room full of co2 than a room full of nitrogen, because you might be alerted by the high co2 a few seconds before the dizziness takes over, but that doesn’t make rebreathers dangerous because you will forget to breathe. If you run out of oxygen, you’re unconscious in a few seconds anyway, co2 or no co2.
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> Plants do it, after all. It's not impossible. The problem is that to reverse CO2 -> C + O2 you need the same amount of energy that you get burning coal C + O2 -> CO2. But burning coal, like half of the energy is lost as unuseful heat. The reaction of plants is different, but plants only has a 2% of efficiency. The chemical reaction of plants is more complicated, so let's be optimistic and assume this reaction has a…
There are reasons you would want to use fossil fuels and use renewables to reverse the process. Fossil fuels have high energy density, can be transported and stored with minimal losses, and consumed anywhere anytime. There are lots of things that are difficult to directly electrify like say planes. You can't simply stick a bunch of batteries on a plane to replace a jet engine and its fuel tanks. But building an exces…