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Instant water cleaning method ‘millions of times’ better: study

cardiff.ac.uk

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Re: Instant water cleaning method ‘millions of times’ better: study

#51

Post by wanderingmind »

icegreentea2 wrote: post #14
slownews45 wrote: post #5

Anytime you read things like 100,000,000 times more effective - you should be asking, what was the numerator or denominator in this. Or are they just describing some tiny part of the system. For example, normally you need to filter, do settling for sediment etc - how did they solve all this? Given the orders of magnitude involved here a 5 MGD plant could produce 500 trillion gallons per day of "commercial approach" w…

The specific measure appears to be in CFU/mL of E. Coli in their test sample before and after. As you suspected, this does not include filtering or settling, just clearing out bacterial contamination. I haven't read the paper yet (paywall)- just looked at their supplementary data. The increased effectiveness appears (guessing here a bit) to be in terms of bacteria load reduction given similar concentration of bacteri…

This is the trouble with most academic research which focuses on trying to maximize one aspect of the problem while a useful commercial application needs to simultaneously optimize multiple conflicting aspects. A similar stream of useless papers also are published in energy storage (beyond Li-ion batteries) which are not likely to be ever commercialized.

Re: Instant water cleaning method ‘millions of times’ better: study

#52

Post by icegreentea2 »

beerandt wrote: post #42
icegreentea2 wrote: post #32

Earlier quoted context omitted.

Right, I don't think these they were really gunning for developed commercial systems for this. Their pitch would be this would be more useful for situations where we might not want to be tied to a chemical supply line. Thanks to fellow poster, I have now started reading the paper. The last sentence of their intro reads: > This approach offers the potential for in situ water purification that could, we propose, be sui…

Part of what will prevent mass adoption is it ignores distribution, which will still require chemical residual treatment, like chlorination. If you have to install chlorinating equipment and operate it, then it becomes a matter of if the marginal savings in chlorine is worth it. However there's also a good chance that chlorine concentration is controlled by downstream factors more than initial treatment- which is bas…

I'm not very familiar with this field, why is chlorination required in addition to peroxide? Is it because it's pretty stable and so provides protection after the water has left the treatment plant?

If that's the case, I suspect that the type of decentralized system the authors think that this is useful for would be a nature where that's less of a concern. Smaller system leading to decreased time/distance between processing and use.

I'm REALLY going out on a limb here, but we hear about people who have to go and fetch their water supplies every day (perhaps multiple trips per day). I suspect that sources on that scale are where this might be useful.

Re: Instant water cleaning method ‘millions of times’ better: study

#53

Post by rdiddly »

wanderingmind wrote: post #51
icegreentea2 wrote: post #14

Earlier quoted context omitted.

The specific measure appears to be in CFU/mL of E. Coli in their test sample before and after. As you suspected, this does not include filtering or settling, just clearing out bacterial contamination. I haven't read the paper yet (paywall)- just looked at their supplementary data. The increased effectiveness appears (guessing here a bit) to be in terms of bacteria load reduction given similar concentration of bacteri…

This is the trouble with most academic research which focuses on trying to maximize one aspect of the problem while a useful commercial application needs to simultaneously optimize multiple conflicting aspects. A similar stream of useless papers also are published in energy storage (beyond Li-ion batteries) which are not likely to be ever commercialized.

Remember science is still just science; it's not necessarily for commercializing.

Re: Instant water cleaning method ‘millions of times’ better: study

#55

Post by [deleted] »

wanderingmind wrote: post #45
tristor wrote: post #4

Wow, that’s incredible. Since it uses electricity for it’s energy input, this could be readily adapted for use in remote areas powered by solar plus battery. Even in Western nations this is a boon to treat well water sources instead of shock chlorination. This combined with GAC filtration can produce very clean water anywhere you can get sunlight.

It needs gold and platinum catalyst. The trouble would be there would be no catalyst in the plant to process water, the day after it is deployed in a remote area.

[deleted]

Re: Instant water cleaning method ‘millions of times’ better: study

#57

Post by cpottamus »

grenoire wrote: post #2

It seems that for both desalination and sanitation (as discussed in the article) of water is now an energy issue. What are some other basic problems (food, water, temperature management, etc.) we're facing that are primarily energy-bottlenecked?

Per vaclav smil -- Energy is the only universal currency.

Everything is energy-bottlenecked.

Re: Instant water cleaning method ‘millions of times’ better: study

#59

Post by Kaibeezy »

rdiddly wrote: post #53
wanderingmind wrote: post #51

Earlier quoted context omitted.

This is the trouble with most academic research which focuses on trying to maximize one aspect of the problem while a useful commercial application needs to simultaneously optimize multiple conflicting aspects. A similar stream of useless papers also are published in energy storage (beyond Li-ion batteries) which are not likely to be ever commercialized.

Remember science is still just science; it's not necessarily for commercializing.

The researcher himself is directly quoted saying things like “revolutionising water disinfection technologies around the world”. If that’s not backed up by it being feasible or valuable commercially, then the criticism is spot on.

Re: Instant water cleaning method ‘millions of times’ better: study

#60

Post by pomian »

hazbot wrote: post #30
grenoire wrote: post #2

It seems that for both desalination and sanitation (as discussed in the article) of water is now an energy issue. What are some other basic problems (food, water, temperature management, etc.) we're facing that are primarily energy-bottlenecked?

This got me thinking about what we could and could not do if we had a magical a energy-unbottlenecker, say an infinite capacity battery with arbitrary power output. These become much cheaper: - Transport: synthesise fuel from CO2 + seawater. Or charge a battery. - Water: electrolysis of seawater. - Food grown anywhere: Light + water + fertiliser can be made from commonly available materials. Soil is a bit trickier, b…

Transportation. All of those above require it. Up front capital costs.
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