Stanford researchers propose using anaerobic bacteria to break it down, producing nitrous oxide or laughing gas. Then, use the nitrous oxide as rocket fuel, of course, which burns leaving only harmless oxygen and nitrogen as byproducts. Rather than running needless rockets round the globe, the researchers propose that we use rocket-thruster technology to power sewage processing plants, creating a closed loop.
Clean energy from poop to clean up more poop. I like it.
This confused me: Nitrous oxide, aka laughing gas or N2O, is an oxidant not a fuel. Like oxygen it won’t burn, but it will help a fuel to burn faster and hotter. Other oxides of nitrogen have similar properties, but are highly toxic. N2O happens to be nontoxic. Wiki notes that Nitrous can also be catalyzed into an exothermic decomposition reaction. Technically this isn’t burning because burning is the oxidation of a fuel, whereas this is the decomposition of an oxidizer into its components.
The Stanford site has a better explanation. It appears that the benefit of the process is twofold: getting nitrogen out of the water and into the atmosphere where it does no damage, and increasing the amount of methane that can be produced from the sewage sludge. If they can run the plant on N2O, then all the methane is available for consumption by the community.