17 Poop is used to power treatment plants
Once it’s sent swirling down the toilet, human waste embarks upon a recycling journey that might see it end up back on your plate. The first stage of turning poop into power is filtration. Passing through filters and sieves in our sewage system, organic waste is separated from larger materials such as wipes, sanitary products and even oil. Continuing on to holding tanks, this slurry of waste and water is then stirred to allow ‘flocs’ to form, whereby poo particles clump together and fall to the tank floor. Removing the majority of water for separate treatment, the remaining sludge is heated to completely dry out. Anaerobic bacteria is then added to biologically break down waste, and as a result high levels of methane gas are produced. As a highly flammable gas, methane is collected and burnt to produce electricity, enough to power the treatment plant that processes the waste. Once broken down, the remaining dried waste is sent to the agricultural industry to be used as fertiliser. So the next time you’re tucking into your homemade salad, there is a chance you helped to grow the ingredients.