Talk:2982: Water Filtration

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On the activated carbon filter, that's a double entendre, referencing both activated charcoal filters often used in filtration systems and the nearby neutron source, which is radioactivity activating the carbon. 172.71.254.23 04:32, 7 September 2024 (UTC)Corsac

There are a bunch of processes shown that are real, but not actually used in water filtration. For example, electrolysis is used to make hydrogen and oxygen gas, and reverse electrolysis is used in fuel cells to produce electricity, but the electricity cost of doing these steps to purify a useful amount of water would be prohibitive. 162.158.159.14 06:18, 7 September 2024 (UTC)

On the other hand, it would be a kind of "extra-intense distillation". We already basically have been "distilling water", as I see it, with the autoclave/condenser pairing that would certainly leave any remaining dissolved minerals or particulates behind. By splitting then recombining the component elements (and some basic gas-chromatography process, not shown) then you'd inarguably get water out that's about as pure as you can hope for in even the most paranoid fantasies about the need for clean water.
...of course, here it's not even the most energetic attempt to further 'refine' the components of "watery matter", with the assumed luxury of having energy (and indeed water) to burn... 172.69.194.219 06:39, 7 September 2024 (UTC)
Yes; I'm wondering if we should be a bit more specific than just "real" vs. "fake". Some of the processes would work, but wouldn't make the water purer; some are impractical but feasible; some aren't possible at all. BunsenH (talk) 16:10, 7 September 2024 (UTC)

Regarding condensers: Condensers are a real method of purifying water, although perhaps not commonly used to demineralize household well water. I frequently buy "purified" water that has been distilled which is simply boiling the water and then condensing the steam into pure water. This is great for use in tea pots or egg cookers or humidifiers to avoid mineral buildup inside the pots. Rtanenbaum (talk) 14:35, 7 September 2024 (UTC)

Regarding adding the well-water back in at the end: "Purified" water is often sold in the baby aisle for use in mixing baby formula, but the labels indicate that minerals have been readded to the water, which of course means it is no longer pure, and would not be useful if I want to avoid mineral buildup in a tea pot. Rtanenbaum (talk) 14:35, 7 September 2024 (UTC)

This comic made me realize how to fund space exploration: selling "artisinal space water" to gullib- I mean, discerning rich people. 172.69.246.151 15:48, 7 September 2024 (UTC)

I have silt, iron, manganese, and microbes in my well.

In a real life, the first step will be mechanical filters: frog-screens, leaf nets, sand or paper media. In my well-water this takes most of the yuck out (as brown sludge).

Home-scale UV treatment is commonly sold (and apparently used; spares available) for spot-treating rural well water. Industrial UV exists for very expensive 'pure water' which must not make anybody sick. ALL water gets germs; UV may have less side-effect than Chlorine or Bromine.

Condensing (and distilling!) are standard household appliances for DIY distilled water. 'Activated' Carbon elements are VERY widely sold for taking taste/smell out of tap water.

"Water softening" (several types) is bog-standard technology out beyond the city mains. (PRR (talk) 19:08, 7 September 2024 (UTC) ...cntd below)

Please sign your comments. And yes, it is. But not immediately before filtering by reverse osmosis. Reverse osmosis should remove almost all solutes, so the resulting pH should be very close to 0 and the concentration of no chemical except water should be significant. Water softening before or after is unnecessary. Don't get me wrong; RO is not perfect. But water softening is only ever necessary to remove large amounts of minerals that can leave scale, and that isn't an issue with high-purity water. EebstertheGreat (talk) 08:03, 8 September 2024 (UTC)
NB, the comment was signed, if you check. This was fifth of sixth straight 'level zero indented' comments. Personally, if I'm not replying (sitting after any number of ":"s, per line) I prefer to add a <br>-tag to force the linefeed (that isn't rendered, otherwise), rather than make it double-LF and potentially look like separate contributors.
It also helps if it's written to look like it's the same contributor (disjointed paragraphs switch narratives seemingly at random don't help... especially), but it isn't foolproof (and unsigned+signed contributions can look like one slightly rambling contributor, hence why signing does need to be added wherever necesary).
But it's all in the eye of the beholder, some of whom may be the posters concerned and be absolutely sure that the future confusion won't exist. And sometimes (very occasionally), there'll be a wish to interleave a comment specifically against an 'inner paragraph' of the wider message you're replying to. You can perhaps copy the 'official' signature of the original flow, like I did here. Can get messy any which way, of course.
Some people might even think it better to (at least in non-reply additions, zero-coloned) just stick to one long rambling no-break paragraph. But I usually find that inelegent both in reading the Talk page and in its edit-source. Being terse and to the point perhaps helps, though, if possible. Not that I'm good at being laconic, as you can see! 172.70.163.48 11:35, 8 September 2024 (UTC)

Of the radioactive treatments, Radon is not mentioned; surely this kills a few germs? PRR (talk) 19:08, 7 September 2024 (UTC)

Using radon would be a bad idea. Even if one got all of the radon out afterwards (e.g. by sparging), it would leave behind radioactive daughter products, as well as the lead at the end of the decay sequences. Granted, radium-enriched water was a commercial product, back in the day, but... still a bad idea. BunsenH (talk) 21:58, 7 September 2024 (UTC)
Yeah, the philosophy tended to be "if it fluoresces, it impresses!", in the pseudoscientific quackery of the time... 172.69.79.183 23:15, 7 September 2024 (UTC)
Wait ... you have filters which turn frogs to brown sludge? Is that legal? -- Hkmaly (talk) 05:24, 8 September 2024 (UTC)

So much that I didn't notice in my first forty minutes looking at the comic while thinking "uhmm wut no! ! !" Y'all are why I come here especially when I think I thought I understood it and didn't need it explained. BTW? Are some for which the explain cannot be complete. The user interactive recent one with squirrels, fans, balls and things that made it kinda a pinball game but most assuredly not (mostly) come to mind. Thank you all. (Edited for clarity}172.70.43.54 04:19, 8 September 2024 (UTC) 172.70.39.34 04:28, 8 September 2024 (UTC)

Are we talking about water treatment, water filtration, or water purification? Because blending water and using UV are useful tools in water treatment but are not filtration and are pointless for purification. Treatment is anything done to make the water healthier or more pleasant to drink or better for equipment. Filtration requires physical separation of water from contaminants (which would not count most of these processes, and some, such as electrolysis, kinda break the definition water systems use since they separate at too fine a level to really count as a water filter anymore, despite the comic name). Purification is the elimination of anything that isn't water. I thought part of the joke was that it was supposed to be treatment for home faucets for drinking purposes. I wouldn't care except it would change the classifcation of the columns. 172.70.178.122 10:49, 8 September 2024 (UTC)

Some references on how hypotonic water doesn't harm human beings: https://www.medicinenet.com/is_drinking_distilled_water_good_or_bad_for_you/article.htm https://www.medicalnewstoday.com/articles/317698#is-it-safe Nitpicking (talk) 12:58, 8 September 2024 (UTC)

There's degrees of harm. Generally agreed that the danger isn't anywhere as bad as the 'scare stories'. (As per edit-comments, you don't explode from osmotic pressure by trying even a squirt of the ultrapure water sat around in school chemistry labs, but it probably saved having to resupply so much if incautious pupils didn't glug it down constantly.)
For example, https://www.webmd.com/diet/distilled-water-overview certainly says that it's safe, but still does point out that...
Distilled water lacks even electrolytes like potassium and other minerals your body needs. So you may miss out on a bit of these micronutrients if you drink only the distilled stuff.
Some studies have found a link between drinking water low in calcium and magnesium and tiredness, muscle cramps, weakness, and heart disease. Also, distilled water may not help you stay hydrated as well as other kinds of water.
...and this is reflected in many of the respectable "is it safe/dangerous?" articles. (The medicinenet link you give actually goes into more detail on these points. Don't know about medicalnewstoday, as I can't even easily get past its "privacy notice" 'cookiewall', the way it's configured.) Thus if we're discussing why we're adding this at all (and end up with "isotonic" being a buzzword, because it sounds better than "flavoured sugar water with some mineral salts"), I had tried to explain why it could be thought necessary to proportionately undo basically the prior (often unnecessary/improbable) purification process. Couched in terms (I imagined) would not promote the "your body asplode!" myth, either. 172.70.91.90 13:33, 8 September 2024 (UTC)
I don't feel like an edit war, but in fact ions are not lost, period. The gut actively transports ions in, the osmotic pressure difference is nowhere near enough to remove ions that way. You don't get the ions in tap water, but they aren't actually nutritionally significant for essentially anyone.Nitpicking (talk) 01:54, 9 September 2024 (UTC)
I don't think you're arguing about quite the same thing, if you want my opinion. But - unlike you lot - I'll not expand huge paragraphs on this issue. 172.70.91.201 10:29, 9 September 2024 (UTC)
You may lose more ions in mouth than in gut. Nevertheless, it's not dangerous amount, and while ions in tap water can be handy and may allow you to survive longer without eating (especially when sweating), if you eat normally, balanced diet, you get much more nutrients in food than in water. -- Hkmaly (talk) 22:35, 11 September 2024 (UTC)

"It is unclear what happens to the neutrons present in the oxygen nuclei" They're used in the Neutron Source. Vkapadia (talk) 20:01, 11 September 2024 (UTC)