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Sadly, it's terrible to use some clean tap water for processing poo, it uses a lot of energy and resources to clean that water afterwards.

Dry toilets/compost make a lot more sense




Smell problems aside, how do you transport the compost away from the toilet?

Expecting people to shovel their shit is almost reasonable in a setting where you live in a house with a yard and could actually use the compost, but what about an apartment building, or a high rise office building?

I really like the idea of using grey water to flush toilets, which at least takes 1 level of water cleaning out of the equation. I used one of those toilets that fills the tank after you flush, through a tap that drains into the tank. You washed your hands while the tank filled and eventually flushed. It was pretty neat.


> Smell problems aside, how do you transport the compost away from the toilet?

The Night Soilman (https://en.wikipedia.org/wiki/Night_soil) or dunny man in Australia would come and collect it once a week. It really wasn't that long ago in some parts, Brisbane Australia had them until the 70's and it's still within living memory of much of the developed world. In many older cities you'll still see little lane ways between rows of houses that were used to give the carts access to the outhouse, most have been converted to footpaths/bikepaths these days.

I wouldn't want to go back because the smell in the summer heat was legendary, but flushing toilets are incredibly recent.


In centuries past, night soil was used as fertilizer and there was a business case for collecting it. Today, human waste is avoided as fertilizer for a number of reasons (hormones and other medication residues, pathogens), and so there is no more business case for collecting it. One would have to advocate solid waste collection as a new public utility, and that might be an uphill battle.


I haven't read the article yet, so apologies if this is covered, but the new Bloomberg office in London has vacuum toilets, like on an aeroplane, which don't use any clean water:

https://www.bloomberg.com/careers/blog/eco-friendly-features...


If you think the link is an article you're in for a pleasant surprise and a very huge rabbit hole. I really suggest you take a look.


How right you were. I started, as one does, with Hitler and Lady Gaga, and continued naturally from there.


Wait, my visit was Lady Gaga- and Hitler-free. Just blockading about their (admittedly fascinating) new building.


I think klez was referring to the Toilets of the World site, not the Bloomberg puff piece.


Or lookup incinerating toilets. Then you just get ash afterwards to cleanout weekly.

Seems to take about a kilowatt per flush.

If you have property, graywater isn't hard to handle in for landscaping/gardening.

Too bad fancy ones cost $5k. I think if we can get them for $500, we could see homes without any sewer connections at all.

https://www.cinderellaeco.com/ca


> Seems to take about a kilowatt per flush.

That's a meaningless statistic without the duration of the flush.


I meant 1 kWh. Dunno how long each cycle takes. They recommend running only one cycle at a time.


That is a lot of energy.


Vaporizing water is hard.


> Then you just get ash afterwards to cleanout weekly.

If you only have to clean out your ash hole weekly, then getting rid of the toilet paper is not a big issue.


I'm interested in full time RV living and some people change their toilet for compost ones, and then turn their black tank (toilet flushes) into a extra grey tank (sink, shower water... Washer or dishwasher if you have a fancy rig with it)

Was watching and reading about them, but not sure If I'd like them... Someone kept a spray bottle to help clean the inside after each use if messy inside (think poop or maybe period blood).

Then there's a little fan that is sorta like a PC fan... but was reading somewhere someone's went out and their RV got invaded by fruit flies!

I like the idea of saving water when boondocking, but seems like some huge cons.


Composting human fecal matter seems like a very bad idea hygienically, because of parasites (flatworms, roundworms, protozoa, etc.).


Right, people have very different diets, more or less natural, some have many parasites, or are on some drugs, so their fecal matter are much less easy to process.

But there are already problems with traces of drugs in tap water, so it can't be that bad, there are many things like mushrooms, or bacteria at a smaller scale, capable to recycle toxicity


It is not a bad idea per se, just harder to do vs. non-human waste composting. Temperatures have to be more tightly regulated and obviously the handling of the raw waste carries an increased risk for workers but it is not working with dynamite levels of risk, it is relatively safe.


You seem to be more knowledgeable on the matter than me, do you know how long parasitic worm eggs or protozoan cysts need to compost in the worst case before ceasing to be viable?


Doesn't industrial composting use heat to deal with pathogens?


I am far from an expert, but for biodegradation you need bacteria, earthworms, etc.; which would die, too, if you killed the harmful worms and bacteria; meaning you would need to mix in other ones. That whole process of killing almost everything and then colonizing again seems like quite an overhead.


Sure but you really do not need that high temperatures, you get enough heat in a humanure compost (aerobic and active) to kill the common pathogens dangerous for humans.


Source needed.

Firstly, I doubt heat alone is what kills those pathogens that do die.

Secondly, parasitic worm eggs and especially some parasitic protozoans are more resistant than pathogenic bacteria.


Septic systems need a fair amount of water with the waste to work correctly - more than one flush worth. (washing hands, showering, and other water uses more than makes up the difference)




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