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Water Filtration With a Tree Branch
Taco Cowboy writes "Dirty water is a major cause of mortality in the developing world. 'The most common water-borne pathogens are bacteria (e.g. Escherichia coli, Salmonella typhi, Vibrio cholerae), viruses (e.g. adenoviruses, enteroviruses, hepatitis, rotavirus), and protozoa (e.g. giardia). These pathogens cause child mortality and also contribute to malnutrition and stunted growth of children.' People have been working on engineering cheaper and cheaper filtration systems for years, but now a group of researchers has found a promising and simple solution: a tree branch. 'Approximately 3 cm^3 of sapwood can filter water at the rate of several liters per day, sufficient to meet the clean drinking water needs of one person.' 'Before experimenting with contaminated water, the group used water mixed with red ink particles ranging from 70 to 500 nanometers in size. After all the liquid passed through, the researchers sliced the sapwood in half lengthwise, and observed that much of the red dye was contained within the very top layers of the wood, while the filtrate, or filtered water, was clear. This experiment showed that sapwood is naturally able to filter out particles bigger than about 70 nanometers.' The team tested E. coli-contaminated water, and the branch was able to filter out 99 percent of the bacterial cells."
If this is true, then this is a really profound discovery that could help millions of people.
What I'm wondering, is why no other society, that we know of, has discovered this low-tech, yet seemingly incredibly useful thing previously?
I don't respond to AC's.
"It's so beautiful. It's hard to believe these spores could kill me."
...I hope it leads to cheap and widely accessible drinking water.
Coca Cola and Pepsi will do all they can to make sure that never happens. Water is big business. That is why access is so difficult.
“He’s not deformed, he’s just drunk!”
Filtering out "99%" of harmful bacteria may be like filtering out 99% of bullets fired at you....
Trees are great at dealing with bacteria.
http://faculty.vetmed.ucdavis....
Filtering out "99%" of harmful bacteria may be like filtering out 99% of bullets fired at you....
So, I take it you're not a fan of Lysol or Purell?
What a silly thing to say; as if not filtering 99% of something harmful is a better idea...
An enigma, wrapped in a riddle, shrouded in bacon and cheese
"Somebody probably thought of that" is more likely to be untrue than true. You probably are the first person to think of that. And even if you aren't you might be the first person to act on the idea. And even if you aren't you might be the first person to succeed where others have failed. And even if you aren't, you might learn something. So don't ever say that, "somebody probably thought of that."
Filtering water through wafers of wood is not obvious to me. I do engineering for a living. If you are wondering why no one ever discovered something before, go back to paragraph one and repeat.
Take what? Take their money to the bank when their plastic funnels and tree-branch-filtration kits sell like hotcakes to the very folks hoping to, ahem, "stick" it to the man?
Account -> Discussions -> Disable Sigs
Well, it's not completely free -- someone likely owns those trees. And people living in desert regions of the world don't have easy access to sapwood -- nor do people in parts of the world where the sapwood is of the wrong consistency in local trees (hardwoods, for example).
The article quoted above points to a paper that has some diagrams that shows how water would go through a branch -- no hoax here.
In brief, find a stalk of sappy wood -- my Dad showed us every spring how to make a whistle out of alder branches that look what the picture shows -- peel it, whittle it to size and then plug it into the end of a tube and gravity feed water through it.
simple...ank
Still hoping for Gentle Treatment...
If you'd RTFA, you'd know they put branch into a tube (fit tightly) and fed the water thru it that way.
Yes, it is. And I'd rather be hit by the one bullet than all 100 of them. I'd stand a much better chance of living.
Especially since there's a much better chance of your body's natural defenses defeating that 1%
Do not meddle in the affairs of sysadmins, for they are subtle, and quick to anger.
There already are low-cost, natural water filtration techniques being used across the world that produce clean water at a higher rate, like biosand filters. For water projects i have previously worked on, how quickly water is purified has been a significant practical concern for the folks who would benefit from the project. That was the reason that solar stills were dismissed, for example; they require more effort and materials to construct, but even then have a higher flow rate than the xylem filter. Also, how often the filter must be replaced is another big practicality issue.
Maybe so, but do you blend bleach into all of your drinking water?
He's getting rather old, but he's a good mouse.
I'm pretty sure that law enforcement (in the US) and military (anywhere) would frenetically jump at the idea of body armor capable of reducing the probability of bullet injury by 99%.
Ezekiel 23:20
You can make a pretty decent biofilter simply by folding a piece of cotton cloth such as an old Indian sari a few times - it'll remove 99% of cholera and many other particularly nasty infectious agents. Yet people are still getting infected because they don't know about the simple solution - it's not a technology problem, it's a public information problem. And spreading public service announcements among a population where where most people don't even own a radio is a serious challenge. Doable, but expensive and there's no profit in it, so it usually falls to small humanitarian organizations that do their best to make the information go viral, and usually fail. Getting a meme to go viral is a lot more difficult when it can only spread through face-to-face interactions.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Water-borne pathogens in the kingdom Animalia are usually called "predators" rather than "pathogens". But yes, pathogens such as A. Mississippiensis can be filtered from the water with an appropriately-sized tree branch.
Maybe so, but do you blend bleach into all of your drinking water?
What, you don't?
If hydrating doesn't result in debilitating stomach cramps, you're doing something wrong, bro.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Welcome pedant, thank you for joining the party. Note how you had to pretend you didn't know the intention of the writer, that's the part where you can tell you've added no value to conversation.