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Comment by deepdriver | Hacker News Reader

Are there effective best-practices to sanitize human waste for manuring? I’ve skimmed the “Humanure Handbook” which suggests a combination of composting (aerobic decomposition) and time (about one year). Are quicker and more energy-intensive options, like charring, equally effective at sanitization without removing plant nutrition?

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Best practices are that you really shouldn't. The potential value of human waste as an additive to growing food is (vastly) overwhelmed by the potential for pathogen spread, pharmaceutical pollution, the whole nine yards.

The longest-running project I'm aware of is https://en.wikipedia.org/wiki/Milorganite , which is similar to what you are asking, if you want to go for a deeper dive in the subject.

Thanks! Had never heard of Milorganite. My interest is purely one of curiosity, specifically how waste might be recycled in a Mars or Moon colony. The Chinese regenerative life support project Lunar Palace 1 claims 41% nitrogen recapture from solid waste, using a "bioreactor" i.e. flippable compost bin:

https://en.wikipedia.org/wiki/Yuegong-1

https://pubmed.ncbi.nlm.nih.gov/27912029/

It's unclear from the published results whether the crew ate food grown from this compost, or just measured the output's nitrogen content.

In Sweden "milorganite" like processes are as far as I know fairly common, but there is controversy around heavy metal and antibiotics content.

Municipal sewage is pretty commonly added to green waste compost products, in an industrial facility the temperature can be brought up pretty high quickly so I don't reckon the process is more time consuming than processing any the green waste itself

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