New Scientist: A newly-discovered type of bacterium that converts ammonium into nitrogen and methane could drastically reduce the amount of energy needed to process sewage.
Researchers from the Delft University of Technology have developed a technique using this new bacterium that by-passes one of the most energy-intensive processes in sewage treatment. In conventional sewage treatment, bacteria convert solid waste into methane and a liquid waste containing ammonium. This ammonium is then digested by other bacteria that require a constant supply of oxygen, which must be pumped in, consuming megawatts of power.
The new technique cuts out this second stage, as the newly-discovered bacteria process ammonium directly into nitrogen gas and methane gas, the latter of which can be collected and used to generate power. So instead of consuming power, this new treatment process could generate it.