The presentation addresses the topic of energy neutrality in wastewater treatment plants, analysing strategies and innovations for reducing the carbon footprint. The material and energy balance in sewage treatment processes is examined, with a focus on optimising consumption in the sludge line.
The role of anaerobic digestion as a key solution to improve energy efficiency, maximise biogas production and reduce the volume of sludge for disposal is highlighted. Different scenarios are compared, from traditional aerobic stabilisation to the combination of anaerobic digestion and thermal hydrolysis, analysing their respective impacts on energy consumption and greenhouse gas emissions.
Another relevant aspect concerns the recovery of energy and materials from sludge, through valorisation processes that allow sewage treatment plants to be integrated into the circular economy model. The importance of monitoring N₂O and methane emissions is also emphasised to ensure that the adoption of more sustainable energy solutions does not lead to negative environmental impacts.
Finally, the need to consider not only energy consumption, but also factors such as emissions, operating cost and waste management, for a complete assessment of the carbon footprint of plants is emphasised.
