State of Knowledge of Scope 1 emissions from Sewage Treatment Plants

Before wastewater, (which includes sewage), can be recycled or released to the environment, it must be treated to remove harmful microorganisms and pollutants. The problem is that this treatment process generates methane and nitrous oxide, and both are even more potent greenhouse gasses than carbon dioxide. Some water utilities capture methane and use it to generate electricity, then use this to run the wastewater treatment plants, but nitrous oxide emission and capture is more of a problem. Nevertheless, accurate greenhouse gas accounting and reporting is required by law (the National Greenhouse and Energy Reporting Act 2007). This project aims to review and collate information about the influence of wastewater treatment technologies, and their operation, on greenhouse gas production. This will be combined with the installation of a gas analyser at a wastewater treatment plant in Australia, and the subsequent measurement of greenhouse gas emissions that are directly related to operating conditions. Outcomes from this project have the potential to modify treatment plant operating conditions in ways that will reduce greenhouse gas production.