Slashdot Mirror
Don't Eat The White Snow Either
loteck writes "An interesting article about an Australian ski resort that is converting human waste into freshly driven snow. The waste is converted "through a three-step purifying process of UV light filtration, ozonation and ultra-filtration", and they say it's "even cleaner than that made from nearby creek water." I think that says more about the creek than it does the waste."
I've heard of another project that uses semi-processed waste water to make snow. The process of making snow, in which the water is mixed with some other stuff ("chemicals", they are called, I think ?), then sprayed under very high pressure. As the water emerges from the spray nozzel, the sudden depressurization causes the cells of any living organizims (say , germs, or bacteria) to burst, effectively disinfecting the water on a microscopic level.
And they swore you couldn't tell it was sewage...
-------------------------
A person of moderate zeal
My other thought is, I'd imaging there must be some sort of minimum standard for the cleanliness of the water to make snow (no, there probably isn't a national standard like there is for drinking water), but there's probably some maximum amount of crud allowed in the water to not clog up the snowmaker machines. I've never been skiing, but don't you generally have several layers of clothing on, and nearly every part of your body covered? I don't think too many people are getting sick from the quality of the water used in snowmaking. Plus, are you eating it? Maybe the guy in the footage from ABC's Wide World of Sports (" .. and the agony of defeat... ") ate some snow, but most skiers probably don't ingest the snow.
I'm glad to see that they're purifying their sewage that much, but wouldn't it have been treated properly before this system was put in palce, and then discharged into a creek for other users (human, plant, and animal alike) downstream to use?
just thoughts from a non-skier, non sewage plant operater..
i agree...the concept i'm referring to though, is the concept of water purified through man-made means, as opposed to nature which most people are more used to. in singapore's case, they're currently pumping the purified water into reservoirs, just to let it sit in the open so the birds and fish can crap into it and let nature do a bit of its thing, before purifying it again to pump into the water supply. all this, just to satisfy the odd inhibitions that a lot of people have to consuming purified sewage. weak-minded people really do bother me sometimes.
"even cleaner than that made from nearby creek water." I think that says more about the creek than it does the waste.
A typical knee-jerk reaction that nearly all of us have, myself included. But perhaps quite an unfair one.
This is going to seem a little off-topic. Bear with me!
We seem to be quite often short of water these days, and since we don't have a lot of new water catchment possibilities, it would seem that it can only get worse as the population increases.
Saving water seems to be the key here. Not only through more efficient appliances, but also through multiple uses of our water. How much sense does it make to be flushing our toilets with drinking water?
Some houses already capture "grey water" and use it for tasks where drinking water is not required. Obviously there's some filtering required. I've heard of other projects which are completely water self-sufficient. Yes, you end up boiling your potatoes in recycled piss!
Pretty revulsive to us today, but who knows? Maybe our grandkids will find it completely normal.
I saw a show on TLC or Discovery about 6 months ago about a project in Southern California that was taking treated water that would normally go into the Pacific and re-distributing it to homes on a second water main. Water coming off of this "second main" would be used for toilets and outdoor spigots. While this water was just as clean (if not cleaner) than the water coming in on the primary main, people couldn't get over the idea that the water was once (recently) in someone's toilet.
--Mike
I can't find exact figures, but I guess that each guest could easily produce 100 litres of waste 'liquid' each day, once you've taken into account all the water that is used in washing your teeth, showering, washing the plates you used for brekfast etc, etc.
If you could reclaim 95% of that water at a reasonable cost/efficiency then you're looking at 700,000 litres over water a day. Which would make quite a bit of snow.
Even if the resort saved just 1 cent per litre by not having to have more piped in that'd be a saving of $7000 dollars a day, definitely not to be sniffed at (or tasted
"Free software as in beer, copy protection as in racket" - Telsa Gwynne
Avogadro, urine and eternal recycling
:-)
A calculation of what would happen if we'd dilute all the urine from one days urination of the world population into all the 1.4 billion trillions litres water on earth. Yes, thank god for the internet putting questions like these into rest.
Beware: In C++, your friends can see your privates!
Back in the early 90's my dad was on some summer program where professors would go and do work for NASA and then during the year be the regular profs that they were.
He was an analytical chemistry professor and then for NASA worked on the water filtration system for the Space Station.
The basic concept being that water is heavy at 8lbs/gal and so if they can limit how much they take up, they can use that saved weight towards carrying something else.
So they wanted to bring up a small fixed amount and then recycle out the waste - so when you took a leak, it would recover that and clean it out (with very similar methods to this article interestingly enough), and then... according to my dad - was usually cleaner than the water they brought on.
I was always puzzled at why they didn't just bring on cleaner water - but I suppose he was also hinting at the astronauts bringing some inside themselves as well... don't know.
There are some odd things afoot now, in the Villa Straylight.
Cells tend to rupture when frozen, either because the ice inside expands and bursts them (fast freezing) or because long, sharp, pointy ice crystals inside form and pierce the cell membrane (slow freezing). The temperatures typically found on ski slopes (within a few degrees of zero Celsius) are ideal for the formation of large ice crystals. There are also dehydration processes at work. Finally, cells left outside in slightly warmer weather still don't do well, because they'll starve to death. (Researchers who want to preserve cells long-term store them at liquid nitrogen temperatures to stop all metabolism.)
Recent research has suggested that freezing and thawing will also disable many viruses--apparently it damages the surface proteins they use to bind to our cells. Experiments conducted on freezing whole blood for storage revealed that freezing also inactivated much of the HIV in test samples. Some jurisdictions are now considering freezing all donated blood as an additional safety precaution before transfusion.
Not so say that freezing is a panacea--there are a number of nasties that will survive the process (encysted bad guys are often reisistant) but the frozen stuff is significantly cleaner than what came in, and it may well be cleaner than what's in most rivers.
Yes, I read the article, and yes, I realize that they filter and treat the water extensively before turning it to snow...but all that work might be overkill.
~Idarubicin
Not entirely accurate, but it has a factual basis.
It should be remembered that the percentage of household waste water that is urine is actually very small. e.g. more water is used to flush away a piss than is actually piss. Then there are people showering, having baths, washing clothes, washing dished, cooking etc etc etc.
It's not all that bad when you look at it closely.
What actually bothered me when I lived in London was that the base amount of oestrogen (spelling?) was climbing due to the huge number of women on the pill. This was then linked to rising male infertility in the London area.
To be safe - I drank only bottled water. Now my nuts have produced offspring - I don't mind so much.