The Tricky Economics of Human Waste

Marketplace reports that an effort in Chicago to turn human waste into fertilizer has run into local opposition due to higher-than-expected costs. The actual practice isn’t that unusual: “Chicago’s not alone; lots of municipalities all over the country, all over the world actually, recycle human and industrial waste heavily treated into little pellets that are fertilizer.” Further reading here.[%comments]


Eric Hamilton

Back in the 70's I was in Chicago at the annual flower show. They had a booth that was giving away "nu-earth", or some similar name, for free. (I got some and was goint to give it the next person thant gave me any s***.) They said that it was the output of their sewage treatment plant and they would give away to anyone that wanted it. That included that they would fill up a dump truck if you came to the sewage treatment plant. There was a note with it that said "May get an earthy smell when wet"!

ACW

Our ancestors used to use "night soil" on their farmland and gardens. I thought, though, that it was nearly impossible to render human excrement safe for such use nowadays, because of high concentrations of heavy metals. (Which isn't reassuring, because, um, what comes out must have, in some form, gone in.) Possibly a treatment method that makes it usable has been developed since that factoid came my way.

Drill-Baby-Drill Drill Team

Ironically the Salmon caught in Puget Sound, the bay off Seattle, is caffeinated. Caffeine is not naturally occuring in the ocean. But a lot of Seattle residents are Starbuck's addicts. You do the math.

I am sure the Salmon also has high levels of Prozac and Viagra.

Doctor: Take One Fish and Call me in the morning.

Teach a Man to Fish and he is energetic, happy and doesn't suffer from EDS.

Ron

As I understand it, Milorganite is one such product, converting the sewage from the breweries into pelleted fertilizer. The problem with all of these, as mentioned, is that the municipal waste stream includes heavy metals and all manner of industrial and medical waste.

By baking the sewage at very high temps (800 degrees, if I remember?), it renders a pelleted product and kills off any pathogens. The levels of heavy metals are within the guidelines put forth by the EPA, although not recommended for vegetable gardens (comforting, eh?).

If we could stop mixing all the 'waste' streams together, the end product could be much higher quality and safer... something we'll need to think about as potable water supplies dwindle in many areas, fertilizer (petroleum) becomes more expensive, and the consequences of our current 'treatment' methods continue to become more apparent.