Water Filtration With a Tree Branch

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unruly

Member
Jan 8, 2014
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0
Suthriganaweorc
Approximately 3x3x3 cm of sapwood can filter water at the rate of several litres per day.

An MIT team has discovered that this low-tech filtration system can produce up to four litres of drinking water a day.

I've not tried this yet but apparently if you break off a branch from a pine tree, peel away the bark, and slowly pour water through the stick. The improvised filter should trap any bacteria, producing fresh, uncontaminated water.

The researchers have published a paper summarised in this article.

I'm not sure if this is a new idea but its the first time I've heard about it. Has anyone tried this?
 
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Teepee

Bushcrafter (boy, I've got a lot to say!)
Jan 15, 2010
4,116
4
Northamptonshire
Fascinating, thanks for posting.

Easy to have a play with too. I'm wondering if a jubilee clamp or string tourniquet and some large tubing would adequately seal to the stick but still allow a flow. Maybe pine resin could seal the join.

I need to have a play with this for curiosities sake.
 

Jared

Bushcrafter (boy, I've got a lot to say!)
Sep 8, 2005
2,548
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Wales
Very interesting.

Claiming at least a 99.9% success rate removal of bacteria.

But still means you have to deal with viruses by a further stage.
 

Macaroon

A bemused & bewildered
Jan 5, 2013
7,115
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SE Wales
Very interesting article indeed, but seems it needs a bit more research before becoming a reliable real-time solution..............

Good find, thanks for posting this :)
 

British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
25,534
407
Mercia
Considerably easier than pouring water through a stick though!
Break off a branch from the nearest pine tree, peel away the bark, and slowly pour lake water through the stick.
is so stupid as to be laughable
 

unruly

Member
Jan 8, 2014
47
0
Suthriganaweorc
Thanks for the replies.

I was thinking of making a tapered plug and wedging it into a hole in the bottom of something like a bucket.

Teepee I think your idea of sealing it with pine resin is a great one.

I may try this out to see if it removes food colouring before commiting to drinking the results.
 

British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
25,534
407
Mercia
Bear in mind, that improvising a water filter in the field would be an act of extreme desperation. Even microscopic gaps at the side of a "plug" would be sufficient to pass microbes through to the "filtered" water. It would be much safer to simply filter the water through a few layers of cloth and then boil it. The idea of using wood as a filter medium is a good one - but I personally don't consider it a viable "emergency" technique
 

Macaroon

A bemused & bewildered
Jan 5, 2013
7,115
270
70
SE Wales
Bear in mind, that improvising a water filter in the field would be an act of extreme desperation. Even microscopic gaps at the side of a "plug" would be sufficient to pass microbes through to the "filtered" water. It would be much safer to simply filter the water through a few layers of cloth and then boil it. The idea of using wood as a filter medium is a good one - but I personally don't consider it a viable "emergency" technique
I agree - this is pure theory, and seems to me to be likely to stay so for a good while to come..................
 

Teepee

Bushcrafter (boy, I've got a lot to say!)
Jan 15, 2010
4,116
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Northamptonshire
Is Unrulys fist post in this thread missing for anyone else?

I see the sealing around the stick as the issue too. Epoxy was used because it's a very 'wet' fluid and will soak into the wood fibres effectively, making a seal. This needs replicating to force the water through the wood without microscopic gaps.

The plug forced into a bucket may work with some additional sealing.

It's not got much merit for a survival situation, I agree. Much more efficient to just boil water (If you have a container) but the ease of which a stick can be shaped to fit a union, it's ease of availablity, knowledge that the pine stick is reasonably clean and it's need to have the knife shown to it gives it some merit for having a play with.

I think I'm going to rig my drinking bladder up and mate a stick into it to see how it compares to my normal gravity fed system. :)
 

Frazer

Tenderfoot
Dec 18, 2009
64
0
Highlands
I'm going to assume it was one of these articles: https://www.google.co.uk/search?q=water+filtration+with+a+tree+branch&tbm=nws

Break off a branch from the nearest pine tree, peel away the bark, and slowly pour lake water through the stick. This improvised filter will trap any bacteria, producing fresh, uncontaminated water. An MIT team has discovered that this low-tech filtration system can produce up to four liters of drinking water a day — enough to quench the thirst of a typical person.
In their, the researchers demonstrate that a small piece of sapwood can filter out more than 99 percent of the bacteria E. coli from water. They say the size of the pores in sapwood — which contains xylem tissue evolved to transport sap up the length of a tree — also allows water through while blocking most types of bacteria.
From http://www.science20.com/news_articles/mit_makes_water_filter_sapwood_tree_branches-130604

Makes sense. I'll have to whip up a demo/test piece.
 

unruly

Member
Jan 8, 2014
47
0
Suthriganaweorc
I think my original post disappeared for a while because I edited it. I'm a new poster so it probably needs to be mod checked before it reappears.
 

mrcharly

Bushcrafter (boy, I've got a lot to say!)
Jan 25, 2011
3,246
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North Yorkshire, UK
you need two bits of pipe, one on each end of the wood. Then it doesn't matter if a bit seeps past the edge of the first bit, because the only water going into the second bit of pipe is that passing through the wood.

Sounds like some scientist went to a beer festival and saw them tapping the barrels with the soft plugs, if you ask me.