Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Separating urine from sewage could mitigate some environmental problems

nature.com

Post reply on HN
Print view View original

71–80 of 120 posts

Re: Separating urine from sewage could mitigate some environmental problems

#71

Post by p1mrx »

mschuster91 wrote: post #67
p1mrx wrote: post #66

Earlier quoted context omitted.

Let's stop putting sugar in water; that should solve most of the problem.

The "sugar in water" is not a problem, rather a symptom: it is a very effective and cheap way to get calories into a human. Way too many people lack a combination of access to fresh groceries (they live in "food deserts" [1]), enough money to afford these groceries [2], enough time to cook healthy food [3], or skills to cook food [4] - and most often these issues collide in poor and otherwise disadvantaged people...…

I don't think we should ban cheap sugar, just keep it in solid form. The human brain never evolved in an environment where thirst leads to calories.

If you split soda into water and candy, then at least candy intake is visible and controllable.

Re: Separating urine from sewage could mitigate some environmental problems

#72

Post by Raidion »

pie42000 wrote: post #39
cute_boi wrote: post #37

Earlier quoted context omitted.

This is me to be honest. There are so many things we can do, but it seems we are focusing on thing that may only have superficial benefits.

This is by design. Paper straws are meant to distract your limited focus from things that actually matter.

Alternately, there are a lot of things we can improve, and doing something small that's easily accomplished gets something done now, increases visibility, and add momentum to do bigger things. I know some states are banning (or limiting) plastic bags now.

Does that solve the big problems of container ships burning bunker fuel, oil wells leaking methane, and the huge amounts of plastic caused by drink companies? No, but it definitely makes them look worse, and adds pressure to help make bigger change.

Re: Separating urine from sewage could mitigate some environmental problems

#73

Post by scythe »

jcranberry wrote: post #50
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…

Finish reading the article. >According to Simha’s estimates, humans produce enough urine to replace about one-quarter of current nitrogen and phosphorus fertilizers worldwide; it also contains potassium and many micronutrients (see ‘What’s in urine’). On top of that, not flushing urine down the drain could save vast amounts of water and reduce some of the strain on ageing and overloaded sewer systems. >In a study[1]…

I don't see how that addresses the GP's key point about the cost of replacing wastewater systems in literally every household. If I imagine, say, replacing all the walls in every house with modern insulated walls, windows with double-pane glass, roofs with solar panels, etc, a variety of environmental and economic objectives can be achieved. With regard to the very shiny "up to 47%" reduction in GHGE, this appears to be relative to the wastewater system, not the economy as a whole:

>Urine diversion consistently provides improved environmental performance relative to the conventional system for each scenario for all impact categories, except AP, as shown in Figure 2 (see Table S17 for data plotted in this figure). Both diversion alternatives reduced the GWP, CED, freshwater use, and EP categories from anywhere between 24 and 63%.

As a reality check, there are still tens of thousands of homes in the United States using lead pipes for drinking water. The current regulatory and economic climate has made it infeasible to replace infrastructure that literally poisons people. Any reform that proposes to alter the physical structure of the vast majority of existing residential buildings must necessarily be situated in the context of laws, costs and politics that define what is possible for those buildings, and compared in terms of realistic costs and impact to the scores of other proposals to do similar things.

This is a painful and depressing reality that anyone who has studied American urban development for more than a few months comes to understand.

Re: Separating urine from sewage could mitigate some environmental problems

#74

Post by chrisco255 »

cultofmetatron wrote: post #48
988747 wrote: post #44

Earlier quoted context omitted.

Quoted post unavailable.

and where does the energy and fertilizer come from to do that? right, fossil fuels. Last I checked, there's a currently an existential threat linked to use of those that are the main driver for why all these initiatives are going on. I'm not happy about it either but its a choice between each individual's footprint going down or reducing the amount of individuals.

What exactly is the existential threat? If population is at all time highs, if lifespans are at all time highs, if crop yields are at all time highs, if deaths from natural disasters are at all time lows, what is the existential threat?

Re: Separating urine from sewage could mitigate some environmental problems

#75

Post by i_am_proteus »

jcranberry wrote: post #50
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…

Finish reading the article. >According to Simha’s estimates, humans produce enough urine to replace about one-quarter of current nitrogen and phosphorus fertilizers worldwide; it also contains potassium and many micronutrients (see ‘What’s in urine’). On top of that, not flushing urine down the drain could save vast amounts of water and reduce some of the strain on ageing and overloaded sewer systems. >In a study[1]…

Yeah this here's a good post by j cranberry.

At the end of the day, humans and animals are both part of a cycle of nutrient use and recycling those nutrients from waste, be that human waste or animal waste, is a way to cut down on synthetic fertilizer use.

Some bits from the USA [0] [1] [2] that y'all might find informative. Important part is that manure comes in different varieties and it's not all a 1:1 replacement for synthetics in the way farmers use them today.

Also of note is that, just like in Germany, parts of the USA that concentrate livestock have too much bull shit and that's bad for runoff from the livestock operations. But that's the expected result, ain't it? Concentrating feed from fields all over means you're concentrating what comes out of the animal also, which means you need to truck it off somewhere or end up with a local pollution problem.

One other upside of pursuing human waste streams is that we already have a lot of infrastructure in place to process human sewage. Have a look at [3] right here and you'll see the potential— but that's still less than half the phosphorous that Europe uses in the present day. Good news is that cutting back on fertilizer input doesn't result in a 1:1 linear reduction in cereal yields so a reduction in fertilizer availability (after the phosphates get mined out) doesn't necessarily lead to a bad famine.

These are complex systems here and there's no one-size-to-fit-them-all type solution.

[0] https://www.ers.usda.gov/webdocs/publications/42731/16741_ap...

[1] https://www.ers.usda.gov/webdocs/publications/42731/16744_ap...

[2] https://www.epa.gov/sites/production/files/2015-07/documents...

[3] https://www.nweurope.eu/projects/project-search/phos4you-pho...

Re: Separating urine from sewage could mitigate some environmental problems

#76

Post by dpark »

dumbfounder wrote: post #32
hiptobecubic wrote: post #23

Earlier quoted context omitted.

We could also stop producing so much dung...

You jest, but I have thought about this. If we all take fiber pills and probiotics will that reduce waste, and also toilet paper consumption? Should we be introducing these things into the water supply like fluoride? (the answer is no, but would be an interesting exercise to see what impact it could have)

> If we all take fiber pills and probiotics will that reduce waste

Fiber pills do not reduce waste. They increase it. That is the point of fiber. It increases stool. Fiber is also known as “bulk”.

> Should we be introducing these things into the water supply like fluoride?

This is like asking if we should put protein into the water supply. You can’t just dump a bunch of psyllium husk into the water supply. It won’t make it through the water supply and come out of the tap on customers’ homes. It will just gunk up the city pipes, pumps, etc.

If it did somehow work it would make the water supply disgusting to drink and unusable for many domestic purposes.

Re: Separating urine from sewage could mitigate some environmental problems

#78

Post by sgc »

ldiracdelta wrote: post #54
kingsloi wrote: post #42

Earlier quoted context omitted.

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…

One of the weird things about compost toilet is that septic systems exist. If you're on a well in Colorado, you pump up the water, do your business, filter the water through hundreds of feet of earth and then pump up the water again.

Probably not, the water will usually migrate quite a bit before hitting well depth, depending on underlying geology. Composting toilets are also useful in the mountains where septic systems need to be extremely deep or will freeze during the winter.

I do see the space for a septic system designed for rotation - ie that uses a pipe material designed to last X number of years that then itself biodegrades, and can be ploughed and the field used once a sufficient safety fallow period has passed.

Re: Separating urine from sewage could mitigate some environmental problems

#79

Post by causi »

jcranberry wrote: post #50
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…

Finish reading the article. >According to Simha’s estimates, humans produce enough urine to replace about one-quarter of current nitrogen and phosphorus fertilizers worldwide; it also contains potassium and many micronutrients (see ‘What’s in urine’). On top of that, not flushing urine down the drain could save vast amounts of water and reduce some of the strain on ageing and overloaded sewer systems. >In a study[1]…

Are they seriously arguing that fifty percent of a household's water usage goes into flushing urine? That sounds like bullshit.

Re: Separating urine from sewage could mitigate some environmental problems

#80

Post by mschuster91 »

causi wrote: post #79
jcranberry wrote: post #50

Earlier quoted context omitted.

Finish reading the article. >According to Simha’s estimates, humans produce enough urine to replace about one-quarter of current nitrogen and phosphorus fertilizers worldwide; it also contains potassium and many micronutrients (see ‘What’s in urine’). On top of that, not flushing urine down the drain could save vast amounts of water and reduce some of the strain on ageing and overloaded sewer systems. >In a study[1]…

Are they seriously arguing that fifty percent of a household's water usage goes into flushing urine? That sounds like bullshit.

According to [1], toilet usage accounts for ~24% of household water usage. The missing 26% to "about half" likely comes from removing the water usage caused by the production of synthetic fertilizer.

[1]: https://www.epa.gov/watersense/how-we-use-water

Post reply on HN