“Urine separation is alive and well – along with other ways to recover useful compounds from sewage”
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Many years ago, I wrote a feature for New Scientist about an innovation in waste-water treatment called urine-separation toilets, which, at the time, looked like becoming a desirable accessory for the eco-conscious. To cut a long story short, the Western habit of flushing urine away using clean water then separating it out again in sewage plants is extremely wasteful. Toilets that collect undiluted urine separately and send it off for processing into fertiliser save large amounts of energy and water.…