Water-purifying cup makes drinkable water from creeks and streams(cockrell.utexas.edu)
cockrell.utexas.edu
Water-purifying cup makes drinkable water from creeks and streams
https://cockrell.utexas.edu/news/archive/9720-water-purifying-cup-makes-drinkable-water-from-creeks-and-streams-in-minutes
41 comments
I don't think it's a product so much as a proof of concept. The use of electricity will definitely not make this a must-have for backpackers, but maybe the technology can be leveraged for larger scale filtration systems (or just the one you use in your house).
I can see this as a product given the trend of failing infrastructure. Right now, we’re only seeing things like poorly maintained roads & bridges, and failing power grids depending on your area. I predict that water purification issues will go beyond the rust belt if it hasn’t emerged already.
most issues with failing water infrastructure involve non-biological contaminants like lead.
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require replaceable filters, though. I could see that as a tradeoff.
True, but those filters last a very long time. The Sawyer Squeeze (what I use) produces ~1000 gallons of filtered water before needing replacement[1]. I assume others using the same technology perform similarly.
It also filters the water much more quickly. As fast as you can drink it.
[1] Assuming you properly maintain it by backflushing every so often, which is quick and easy, but still necessary.
It also filters the water much more quickly. As fast as you can drink it.
[1] Assuming you properly maintain it by backflushing every so often, which is quick and easy, but still necessary.
warranty is actually lifetime:
https://www.sawyer.com/lifetime-warranty
i think you would need more than the syringe and arm power backflush to really restore a good flow over years, but hey it's only 30 bucks and mine has been working for 4 years
i think you would need more than the syringe and arm power backflush to really restore a good flow over years, but hey it's only 30 bucks and mine has been working for 4 years
True, and they also claim that the filter is good for at least 100,000 gallons. That may be correct and I'm just doing something wrong, but my experience with it is more in line with what most reviewers claim: about 1,000 gallons before I can no longer restore reasonable flow.
As you say, they're inexpensive, so I don't sweat this too much.
As you say, they're inexpensive, so I don't sweat this too much.
I have always kept a pair of Sawyer Mini SP128 water filters in my first aid and travel kits. We were able to use them when we went to South America to filter out stuff in the water that could have made us sick. They’ve been proven to be more effective than the life straw portable water filters. They’re about $20-30 on Amazon.
> the device was able to remove 99.997% of E. coli bacteria from 2- to 3-ounce samples taken from Waller Creek in Austin in approximately 20 minutes, with the capacity to do more.
Though necessary, is that the only metric needed to label water potable?
Though necessary, is that the only metric needed to label water potable?
Not at all.
For instance, in the forests around where I live, there's very high lead levels in certain brooks and ground water reservoirs because of an old shooting range out there where no one ever bothered to clean up the slugs left behind.
For instance, in the forests around where I live, there's very high lead levels in certain brooks and ground water reservoirs because of an old shooting range out there where no one ever bothered to clean up the slugs left behind.
Where is this?
In CA, giardia is a big concern.
There's generally nowhere on Earth where it's safe to drink from moving freshwater because of a lack of evidence (testing) and probable contamination upstream from wildlife. If you were dying of thirst, then sure, take a chance on C. parvum, V. cholerae, and G. duodenalis with glamping toys.
99.997% of doctors agree that it's the .03% that get you.
Sorry, this is press release journalism lacking in a fully-developed, practical application.
In this case, it's still pre-alpha and unable to assure removal of enough viruses, bacteria, protists, and fungi to result in potable water.
In the category, LifeStraw and such are worthless apart from absolutely clear water. They don't have the pressure delta or surface area to do much. One hit of brackish water and you're tossing filters because they become completely clogged. If you want clean water, perhaps ~13 stages with large filters before reverse osmosis via electric pump.
In this case, it's still pre-alpha and unable to assure removal of enough viruses, bacteria, protists, and fungi to result in potable water.
In the category, LifeStraw and such are worthless apart from absolutely clear water. They don't have the pressure delta or surface area to do much. One hit of brackish water and you're tossing filters because they become completely clogged. If you want clean water, perhaps ~13 stages with large filters before reverse osmosis via electric pump.
well, this is literally a press release/announcement from the university, not a work of journalism, so relax.
I'll stick to boiling water and purification tabs thanks. If I'm feeling like I haven't done a good job, I guess I can run it through your filter.
Boiling water remains the most effective way of clearing the water of microorganisms (better than any filter), but does nothing for nonbiological contaminants.
Ideally, you do both. Personally, I'm comfortable with just the filter. In hundreds of trips into the wilderness, the only time I've suffered from contaminated water (giardia -- don't recommend) was when I accidentally drank some unfiltered water. Fortunately, I didn't develop any symptoms until I was back from the trip.
Ideally, you do both. Personally, I'm comfortable with just the filter. In hundreds of trips into the wilderness, the only time I've suffered from contaminated water (giardia -- don't recommend) was when I accidentally drank some unfiltered water. Fortunately, I didn't develop any symptoms until I was back from the trip.
Is this better than my Steri Pen UV sterilizer? Not that I've used it, since I've never had a water emergency.
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It’s been a looong time, but I [barely] remember camping in the 1970s, and having water filters that we used on creek water. These were replaceable units that fit into a sort of bicycle pump kind of thing.
Similar. Not exactly the same, but it has been, like, over forty years.
I thought water from creeks and streams was drinkable anyway, without any filtering. Purification is supposed to be required only for still water, like a lake or pond.
What benefits does this offer over a Brita/ZeroWater filter?
Brita/ZeroWater filters make potable water cleaner such that it tastes better.
This filter makes non-potable water cleaner such that it won't kill you/make you seriously ill.
This filter makes non-potable water cleaner such that it won't kill you/make you seriously ill.
> This filter makes non-potable water cleaner such that it won't kill you/make you seriously ill.
I'd hesitate to even say that much; there are a lot of dangerous contaminants (like organic toxins or heavy metals) which this filter won't touch.
I'd hesitate to even say that much; there are a lot of dangerous contaminants (like organic toxins or heavy metals) which this filter won't touch.
ZeroWater hover filters bacteria, virus and even heavy metals so I would guess that it's better than this solution.
Although you have to change the filters regulary
Where do you get that from? According to https://zerowater.com/pages/frequently-asked-questions,
> Does the ZeroWater® 5-stage filter reduce bacteria?
> The current system is meant to be used with municipally treated, potable water as the current filter will not remove microbiological contaminants.
> Does the ZeroWater® 5-stage filter reduce cryptosporidium?
> At this point ZeroWater® 5-stage filters have not been tested for the removal of cryptosporidium(microbiological cysts).
Both ZeroWater and Brita are explicit that their filters are meant to be used with water that the government has already deemed safe to drink.
> Does the ZeroWater® 5-stage filter reduce bacteria?
> The current system is meant to be used with municipally treated, potable water as the current filter will not remove microbiological contaminants.
> Does the ZeroWater® 5-stage filter reduce cryptosporidium?
> At this point ZeroWater® 5-stage filters have not been tested for the removal of cryptosporidium(microbiological cysts).
Both ZeroWater and Brita are explicit that their filters are meant to be used with water that the government has already deemed safe to drink.
I didn't check my sources correctly. I googled and blindly repeated a non reputable site.
Mea culpa
How do you "filter" heavy metals? They would, I think, be in solution, so it should not be possible to remove them with a filter. (I know the ZeroWater company claims that, but I'd have to know what the basis is for that claim.)
ZeroWater uses a mixed bed ion exchange resin (anion and cation) to attract and hold dissolved ionized solids. Mixed bed resin is very effective and will remove nearly 100% of dissolved solid content which will includes all heavy metals.
The downside of mixed bed resins is that they are not selective and water with high dissolved content (TDS) will deplete the resin at very fast rate. Price per gallon is comparable to bottled water with moderate to high TDS. They are simple and very effective as long as the filter is replaced as needed.
The downside of mixed bed resins is that they are not selective and water with high dissolved content (TDS) will deplete the resin at very fast rate. Price per gallon is comparable to bottled water with moderate to high TDS. They are simple and very effective as long as the filter is replaced as needed.
Ion exchange resin, I imagine.
Gravity-driven carbon granule filters won't protect you from anything apart from making a face when drinking crappy city water. For actually clean water, RO and steam distillation are the main games in town.
I'm genuinely curious about this. What about non-granular-carbon filters, like the sub-.5-micron extruded ceramic-and-carbon pump filters from someone like (the non-Microsoft) MSR? My understanding is those were significantly different from Britta-likes, and were generally a solid choice for deep backcountry backpacking stuff. At least that was what I used doing 40 miles on Isle Royale's interior trails, where nearly 100% of the readily accessible water is wicked-nasty non-moving water, with giardia and cyanobacteria blooms.
Those don't require electricity, are as good at ridding the water of microorganisms, and also filter out many harmful non-biological contaminants.