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Separating urine from sewage could mitigate some environmental problems

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Re: Separating urine from sewage could mitigate some environmental problems

#111

Post by clairity »

Panino wrote: post #95
clairity wrote: post #91

Earlier quoted context omitted.

what about contamination? urine is not always sterile upon elimination from the body, potentially bringing along bacterial, drug, and other contaminants.

The composting process destroys pathogens by several mechanisms. The first is heat: in the pile, thermophilic bacteria raise the temperature through their own biological heat, killing E. coli, Salmonella, etc. My current pile was 149F (65C) yesterday. In a compost pile, those temps will kill pathogens in less than an hour. As a general rule of thumb the following temps/times kill pathogens in compost piles: 140F/60C…

i can certainly believe that composting is amazing at dealing with all sorts of contaminants, but as @hedgehog sorta points to, i'd be worried that the sheer variety of contaminants you could get at a larger population level would present some significant unknown/unforeseeable risks. on a smaller scale, like a single family/household, i'd expect those risks would be more ascertainable and mitigatable.

Re: Separating urine from sewage could mitigate some environmental problems

#112

Post by wonder_er »

c0brac0bra wrote: post #68

Excellent book on the topic of "humanure": https://www.amazon.com/Humanure-Handbook-4th-Shit-Nutshell/d...

agreed! might be oversharing, but I've started this whole end-to-end process, since buying my house in a city. Going surprisingly well, surprisingly enjoyable.

No need to bring in outside fertilizer, not flushing hundreds of gallons of potable water per month into the sewer, and I get top-notch compost to use for growing veggies.

Re: Separating urine from sewage could mitigate some environmental problems

#113

Post by scotty79 »

hedgehog wrote: post #108
Panino wrote: post #105

Earlier quoted context omitted.

I don't know about lithium in compost, but in general, composting breaks down many pharmaceuticals (again, apart from certain chemo drugs). Composting does destroy some anti-cancer drugs like Salinomycin. PFCs may accumulate almost regardless, although I assume composting helps. After all, composting can break down gasoline, diesel, and TNT - though of course you shouldn't add them to a compost bin! Quoting The Human…

Lithium I picked as it's a heavy metal that wouldn't break down per se, though maybe the form it would exist in post-compost would be plenty benign. The sewage sludge issue I'm unfortunately aware of and have been following due to this case: https://www.mainepublic.org/environment-and-outdoors/2022-02... In my area the majority of contamination is from firefighting foams, and I think in the Bay area there's also a lo…

Lithium is not a heavy metal.

Re: Separating urine from sewage could mitigate some environmental problems

#116

Post by hedgehog »

scotty79 wrote: post #113
hedgehog wrote: post #108

Earlier quoted context omitted.

Lithium I picked as it's a heavy metal that wouldn't break down per se, though maybe the form it would exist in post-compost would be plenty benign. The sewage sludge issue I'm unfortunately aware of and have been following due to this case: https://www.mainepublic.org/environment-and-outdoors/2022-02... In my area the majority of contamination is from firefighting foams, and I think in the Bay area there's also a lo…

Lithium is not a heavy metal.

Hah, fair, it's actually light. I don't know to what degree it would get taken up by plants or other food organisms (chickens etc), but if it were then that could be a concern as it's a common medication and the net concentration could climb without removal.

Re: Separating urine from sewage could mitigate some environmental problems

#117

Post by netizen-936824 »

Panino wrote: post #105
hedgehog wrote: post #97

Earlier quoted context omitted.

I would also worry a bit about accumulation of drugs like lithium and other contaminants like PFCs. My suspicion is long term closed loop use of toilet compost for food crops could result in unsafe levels of contamination, have you done any research that direction?

I don't know about lithium in compost, but in general, composting breaks down many pharmaceuticals (again, apart from certain chemo drugs). Composting does destroy some anti-cancer drugs like Salinomycin. PFCs may accumulate almost regardless, although I assume composting helps. After all, composting can break down gasoline, diesel, and TNT - though of course you shouldn't add them to a compost bin! Quoting The Human…

These are all great points, however the issue with PFCs is that they are extremely nonreactive. Things like TNT, gasoline, and diesel are the exact opposite. Those compounds are reactive and quite easy to break apart.

Even so, there must be some sort of either precaution or processing steps that can be taken to minimize PFC concentration, although I don't quite know what they might be.

Re: Separating urine from sewage could mitigate some environmental problems

#118

Post by mschuster91 »

polskibus wrote: post #85
mschuster91 wrote: post #15

> That’s in part because urine is rich in nutrients that, instead of polluting water bodies, could go towards fertilizing crops or feed into industrial processes. Huh? We're already producing way too much fertilizer from farm animals, which leads to the situation that countries like the Netherlands [1] and Germany [2] experience a massive oversupply of dung that has to be shipped sometimes hundreds of kilometers beca…

Do you have a source in English?

I'm German, unfortunately not (and I highly doubt that there would be a market for English news about local German dung market issues anyway).

Re: Separating urine from sewage could mitigate some environmental problems

#119

Post by ThinkBeat »

Urin suitability may vary.

It can contain a lot of recreational drugs, alcohol, prescribed drugs, various other toxins that the kidney is able to sort out.

If a person gets really dehydrated the pee is not good at all. (The body can be pretty fantastic at retaining water if it goes all in. What you pee out in this condition is reasonably toxic and there is little of it. Drinking it "survival tip" is not a good idea since the pee is concentrated and toxic.

Large scale use of human pee may experience odd side effects due to these factors.

Re: Separating urine from sewage could mitigate some environmental problems

#120

Post by kingsloi »

kingsloi wrote: post #42
ciconia wrote: post #30

Drying urine, transporting it, this is extremely energy intensive. There's a much simpler solution: composting toilets. Easy to setup, requires very little input (basically just some dry material like wood shavings (i.e. waste from wood processing that you can sometimes get for free) and you're done. The "humanure" mixed with the dry material goes in a compost bin, sits there for two years, then can be applied to the…

My wife and I rented a Yurt in Fort Collins, CO, near the foot hills of Wyoming. The owner was super eco-conscious/zero-waste. I've not camped for a while, and haven't used anything other than a toilet for years, but something about doing my business in the out house really made the experience 10x better. I think maybe because I feel guilt whenever I flush a toilet that says "3.5-5 gal/flush"... that's a lot of water…

Oops, I meant 3.5-5L/flush.
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