Carbon neutrality of wastewater treatment - A systematic concept beyond the plant boundary.

Recently, every industry has been working to achieve carbon neutrality, and the wastewater sector is no exception. However, little research focuses on the carbon accounting of wastewater treatment and the roadmap to carbon neutrality. Here, to systematically perform accounting, we provide a sketch that describes three boundaries of the wastewater system and propose that the carbon neutrality of the wastewater system is far beyond the plant boundary.