The race is on to develop innovative, cost-effective ways to extract value from waste water instead of just dumping it, writes Sadhbh Walshe
>In a conventional treatment process, ammonia is converted back into nitrogen gas, a non-harmful gas which can be safely released into the atmosphere. The conversion process is expensive, however, and energy prohibitive.
What the Stanford team do, instead, is to use a less energy-intensive process to convert the ammonia into nitrous oxide (N2O), a powerful substance that is typically used to turbo-boost cars or fire rockets.
Normally, N2O is discouraged from forming because it is a harmful greenhouse gas, but when it is burned along with methane it becomes an energy source that can be used to power the treatment facility. According to Scherson, there is a double energy-saving benefit.
“Our process reduces energy input in nitrogen treatment and then the energy from nitrous oxide can potentially be used to power the plant making it energy neutral or even energy positive.”<
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