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I guess when I was born, background CO2 was around 330 ppm. Is there anything I can do to breathe air like that again in my house?
by rufus_foreman 4y ago
I guess when I was born, background CO2 was around 330 ppm. Is there anything I can do to breathe air like that again in my house?
- batch12 4y agoOpen a window?
- rufus_foreman 4y agoIt's 420 ppm outside now.
- ad404b8a372f2b9 4y agoBackground ppm is no longer at 330, so opening a window would not get you there. You would need to keep the window closed and remove more CO2 than you produce.
- batch12 4y agoFair point. I wonder if there is a big difference depending on where one lives. For instance, if one were to live in the country, surrounded by trees...
- rufus_foreman 4y agoYeah that's my question. How would I remove more CO2 than I produce. I've got the window closed, I have a few houseplants, and I am already considering getting rid of Mr. Tiddlesworth, my cat. Is there some sort of machine I can buy? Like direct air capture? I only need this in like two rooms of the house.
- ad404b8a372f2b9 4y agoI don't think so. I guess what you want is a CO2 scrubber like they had in Apollo 13, but I don't know of any consumer, room-scale, ones. Plants make basically no difference sadly, in my room it gets to 1600ppm in under an hour just from me and my cat Gazpacho, although I've admonished him for breathing so much.
- rufus_foreman 4y agoGets to like 1200 here. I think you might have a bad cat. Wasn't Apollo 13 pretty much room sized?
- OJFord 4y agoCertainly wasn't 'consumer'.
- HyperSane 4y agoI will never understand how people can just get rid of their pets.
- rufus_foreman 4y agoYou just drive it up to the country and open the door and let it free. You know? Like, run free!
- lucb1e 4y agoI really don't think they were serious.
- stuaxo 4y agoJust checked my Aranet 4, in a room no one has occupied for a few hours, it's at 497
- pfdietz 4y agoIf the window opened onto 1980, sure. I guess you could try to live in a place where the plants are photosynthesizing vigorously.
- rufus_foreman 4y agoIs that like an actual thing? Like you would have a CO2 meter somewhere and it would be down to 330 because of all the vegetation?
- pfdietz 4y agoWith no wind, a corn field in full sunlight will become CO2 limited in just 10 minutes or so.
- MobiusHorizons 4y agoThat’s fascinating. How do you know? (Research? Personal experience?)
- pfdietz 4y agoI was told that, but I can't find a link for that specific claim. However, I can find a link to some old research that shows CO2 falling during the day in low wind: https://joannenova.com.au/2013/09/plants-suck-half-the-co2-out-of-the-air-around-them-before-lunchtime-each-day/ https://joannenova.com.au/2013/09/plants-suck-half-the-co2-o...
- MobiusHorizons 4y agoThanks for digging that up. Looks very interesting.
- pfdietz 4y agoThis suggests using a greenhouse to absorb CO2 to keep the air you breath fresher. To absorb CO2 at night, plants using the CAM photosynthetic system could be used. These plants absorb CO2 at night for use during the day, storing the CO2 temporarily as malate. https://en.wikipedia.org/wiki/Crassulacean_acid_metabolism https://en.wikipedia.org/wiki/Crassulacean_acid_metabolism
- layer8 4y agoUnlikely: https://imageio.forbes.com/specials-images/imageserve/629c7ef77e1b1a5c654fcbbb/NOAA-carbon-dioxide-level/960x0.jpg https://imageio.forbes.com/specials-images/imageserve/629c7e... That’s in the middle of the Pacific Ocean.
- tpmx 4y ago> background CO2 was around 330 ppm. When were you born and where did you get that number from?
- rufus_foreman 4y agoAround 50 years ago. I was looking at this chart: https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide https://www.climate.gov/news-features/understanding-climate/...
- tpmx 4y agothanks!
- ThrowawayTestr 4y agoGet a co2 scrubber or a bunch of plants.
- rufus_foreman 4y agoIs that a thing? Like a CO2 scrubber you can run at home? That's what I want.
- ThrowawayTestr 4y agoThey exist but you'd have to contact a commercial HVAC supplier. Easier just to get a bunch of plants.
- MertsA 4y agoThere's not an HVAC vendor on the planet selling a CO2 scrubber for a building. All commercial HVAC manages CO2 levels via ventilation with outside air. They'll often use economizers and such to avoid losing all the energy put into conditioning the air for heat and humidity but none of them can ever bring CO2 levels down below outside atmospheric conditions. The only HVAC applications that actually try to reduce CO2 instead of just ventilate are submarines and spacecraft, so good luck trying to make that practical for a house. If I for some reason wanted to try something crazy like this I'd probably look at some of the carbonate solution carbon capture projects out there and try to make that work. As others have already pointed out, plants are a bit of a fools errand here. You'd need to live inside a large greenhouse.
- ThrowawayTestr 4y agoOk, not HVAC. But air scrubbers exist. https://www.alfaintek.com/products/air-scrubber/ https://www.alfaintek.com/products/air-scrubber/
- Reason077 4y agoWhat you really want is a heat exchange / heat recovery ventilation system. Brings in fresh, filtered air from outside, and warms it up by swapping heat with the stale, warm air that it removes.
- yourMadness 4y agoYou could add 80% nitrogen and 20% oxygen to dilute the CO2 to the desired level. But that's not exactly easy or cheap. And dangerous when done wrong.
- rufus_foreman 4y agoHow exactly would I do that? I'm OK with not easy, not cheap, dangerous, and done wrong.
- samatman 4y agoAs long as you're okay with not cheap, Alfaintek has you covered.
- rufus_foreman 4y agoDo I have to relocate to the EU?
- lucb1e 4y agoIncreased social equality and mobility, happiness index, etc. are a free bonus I hear, so I guess one could generally recommend that. Depends a bit on where you're coming from, Norway/Switzerland/Iceland are also not EU for example.
- kragen 4y agoyes but it's nontrivial whitewash curing (lime carbonatation) is the easiest process and the one most used in scuba, anesthesia, and hyperbaric chambers; though it's less energy efficient and involves higher temperatures than amine scrubbers, you can hopefully outsource that part of the process to something outside your house the overall reaction is cao + co₂ → caco₃ caco₃ is 44% co₂ by weight so each kg of co₂ you remove from the air consumes 1.27 kg of quicklime and creates 2.27 kg of chalk with only water as a catalyst this typically takes about three months; without even water it takes about three years. as i understand it, with a few percent of lye as a catalyst it can be complete in under a second, which is how soda-lime cartridges for scuba rebreathers work suppose your house is sealed except for 100 ℓ/s ventilation (212 cfm in medieval units). you're going to be exhaling into it, so maybe you want to reduce the co₂ content from 420 ppm (duude) to 250 ppm, 40%, so you run 40% of the air through a lime scrubber, 40 ℓ/s, which outputs effectively co₂-free air this intake scrubber has to soak up 17 mℓ co₂ per second (420 ppmv of 40 ℓ/s); at 1 atm and 20°, pv/rt gives us 7.1 millimoles per second, which turns out to be 31 mg of co₂ per second, about 2.7 kg co₂ per day, consuming 3.4 kg per day of quicklime and producing 6.1 kg per day of chalk if you're doing this without an alkali catalyst you probably need about 300–400 kg of slaked lime (whitewash or whatever) exposed to air. if we roughly estimate that as 200 ℓ at a 1-mm-thick paint layer it's 200 m² of freshly whitewashed walls. this will probably occupy a cubic meter or two in your house. soda-lime is probably a better option either way you're left with about 190 kg per month of chalk waste (maybe with sodium carbonate in it) that you need to dispose of and replace with a bit over 100 kg per month of quicklime. you could conceivably handle this yourself by burning it in a lime kiln yourself a couple of times a year, but a more pragmatic approach might be to buy four 25-kg bags of quicklime every month (about US$150) or a one-tonne pallet every 10 months. a tonne of quicklime exposed to the atmosphere will probably absorb about a kg of co₂ per day even without water you can reduce this a little by reducing the flow rate but pretty soon your own co₂ breath starts to build up in the space, especially if you're getting jiggy with your husband in bed if instead of scrubbing your intake air you try to hermetically seal your house like a submarine you only need to remove 1 kg co₂ per day (per person) but you have some new problems one is that by removing 1 kg of co₂ per day from the air you are effectively removing [edited] 0.73 kg of oxygen from the air per day, so your oxygen concentration will fall. when it falls by 50000 ppm (50 times through the filter) it starts to become a serious problem. you can do things to replace the oxygen but you can't detect this problem at all without oxygen sensors and it can cause you to fall asleep and never wake up the other is that, with such a sealed life-support system, co₂ is far from the only gas you need to actively manage. water vapor, h₂s from farts, methane from belches, mercaptans from bad breath, and butyric acid from your gym socks all require attention. the life support systems on the iss are publicly documented and i recommend reading the reports to see how they deal with these issues on the other hand you won't be breathing diesel smoke from the semis passing by and you'll be totally set if there's a poison gas attack see also https://news.ycombinator.com/item?id=33579810 https://news.ycombinator.com/item?id=33579810 for the scale required to do this with a greenhouse instead of a lime scrubber, but if you garden you know that's also nontrivial