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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

#11

Post by riknos314 »

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.

The amount of electricity required wasn't mentioned, so while I'm hopeful that you're right I'm worried that the energy requirements will be prohibitive to adoption in many areas.

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

#12

Post by Someone1234 »

This sounds very cool.

Though I wish this article addressed some of the questions I had around commercialization, namely the cost of the gold + palladium, the expected lifecycle, and the expected maintenance routine (e.g. do they have to be regularly removed and cleaned?).

The article makes great arguments for why this should work (i.e. hydrogen peroxide is already being used, this just short-circuits how we get a known effective cleaning agent, reducing/removing logistics inefficiencies). So a lot of the question is: Is this cheaper/less hassle than buying stabilized hydrogen peroxide commercially?

A lot of these fantastic advances often end up in the black hole, wherein they work as advertised, but the financials/logistics never line up and therefore nobody uses them in anger.

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

#14

Post by icegreentea2 »

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 bacteriacidal agents in same volume of liquid.

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

#15

Post by throwaway316943 »

felixfurtak wrote: post #10
xfour wrote: post #3

Waiting for the inevitable explanation of why this is fatally flawed and won’t work at scale?

I guess electrolysis of hydrogen from water isn't really a very efficient process so would therefore need a lot of energy. It's the same reason that we're not all driving around in hydrogen powered cars.

Hence the catalyst

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

#16

Post by TheDudeMan »

gundmc wrote: post #8

How much gold and palladium are required? Those are massively expensive catalysts and it feels borderline disingenuous to talk about how this will bring clean drinking water to the masses without so much as mentioning cost.

"But your majesty, the people don't have any gold for their water catalysts."

"Let them use palladium."

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

#18

Post by osrec »

gundmc wrote: post #8

How much gold and palladium are required? Those are massively expensive catalysts and it feels borderline disingenuous to talk about how this will bring clean drinking water to the masses without so much as mentioning cost.

Given that they are catalysts, they're not being depleted in the cleaning process. Thus, they're a fixed one time cost, albeit a potentially high one.

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

#19

Post by gentleman11 »

gundmc wrote: post #8

How much gold and palladium are required? Those are massively expensive catalysts and it feels borderline disingenuous to talk about how this will bring clean drinking water to the masses without so much as mentioning cost.

> The catalyst-based method was shown to be 10,000,000 times more potent at killing the bacteria than an equivalent amount of the industrial hydrogen peroxide

Even if it required a fair bit, 10M is a really big number. Long term savings would be huge since the catalysts aren’t consumed in the reactions

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

#20

Post by rmah »

Yeah, the use of "millions of times better" just doesn't pass the sniff test. Given that current commercial methods kill 90%+ bacteria in water, thus, nothing can be even 2x better...and makes me suspicious of any claim in the article. Hopefully it can help people in areas that are currently without clean water, but I'm not holding my breath.
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