Waste Not, Want Not: The Future of Toilets


Turning waste into fertilizer in Boston

We have written before about the need to change our waste water system that mixes black and gray water and flushes it away; commenters were not impressed and wrote "Composting toilets are NEVER going to make it into the main stream market. Debating it is silly." But the debate is happening anyways; Rebecca Tuhus-Dubrow writes an excellent article in the Boston Globe on the subject.

"IN A WORLD of rapidly diminishing resources, there's one we tend to overlook. It's easy to produce and extremely abundant. But instead of viewing it as an embarrassment of riches, we're more likely to see it as just an embarrassment.

This neglected treasure is human waste. Urine is rich in nitrogen, potassium, and phosphorus, the three main ingredients in artificial fertilizer. Feces contains these nutrients, too, in smaller doses, and the methane it produces can be harnessed as biogas, a green energy source."
ecosan vacuum toilets

She describes the awful numbers: "Annually, each of us produces about 13 gallons of feces and 130 gallons of urine, which is instantly diluted into the 4,000 gallons we use to flush it. This large quantity of contaminated liquid further mixes with "greywater," the water from the laundry, shower, and sink, tripling or quadrupling the amount of water that must be treated as sewage in energy-intensive plants. In effect, the system takes a relatively small amount of pathogenic material - primarily the feces - and taints enormous amounts of water with it. Especially in regions struggling with freshwater scarcity, many observers have come to see this system as highly inefficient. "It's a totally insane idea," says Arno Rosemarin.[ the research and communications manager at the Stockholm Environment Institute]


vacuum toilet

We are also throwing away valuable phosphorus with our urine, a key fertilizer. "Don't mix what God separates," says one researcher. In Sweden, toilets are being installed to divert urine, which can be used as fertilizer with almost no treatment. Pilot projects have been started where vacuum toilets suck waste away for use in biogas plats to generate energy.


Separating toilets

"There are, however, obstacles to widespread implementation of unorthodox toilets. Space limitations make compost toilets infeasible in most urban areas. Vacuum toilets require a different plumbing system. And there may be psychological barriers to changing habits in the bathroom." ::Boston Globe May require stupid free registration

But we have to start looking at these habits and changes in our plumbing systems. Ten years ago nobody handled their garbage; it all went in one can and some guy in green overalls took it away. Then we learned to separate our recyclables, and in many areas learned the often yucky task of separating our compostables.

We treat our body waste the same way, putting everything into a single pipe, mixing it with industrial waste and pumping it to some distant unknown location. We may have to change our ways and learn how to separate and recycle this as well.

TreeHugger on Composting Toilets
Thinking about Crap: Should Houses Have Composting Toilets ...
Composting toilets: Ready for Prime Time?
TreeHugger Tips: How-to Manage Humanure Composting
TreeHugger Tips: Hacking a Composting Toilet
Composting Toilets Work, Even in Antarctica
The Hot Poop on Alternative Toilets
TreeHugger On Phosphorus
P is for Phosphorus (As Well As Human Urine)
I.P. Freely - On The Organic Cabbages

Treehugger on Separating Toilets

Hot Poop on Composting Toilets: Separett

Tags: Boston | Composting Toilets | Fertilizer | Toilets | Zero Waste

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