Sustainable and innovative wastewater treatment with bioelectrochemical-based sensor and aerobic granular sludge

Gryaab, which operates one of Scandinavia’s largest wastewater treatment plants, plans to install aerobic granular sludge (AGS) technology in an ongoing expansion of the plant.

AGS can accomplish removal of phosphorus, nitrogen, and organic material in the same reactor, potentially without the need for external chemicals.

This reduces the environmental impact of wastewater treatment and provides opportunities for recovery of resources such as phosphorus.

However, the function of the process depends on access to volatile fatty acids (VFA), which are generated during hydrolysis of the influent wastewater.

VFA production and uptake are difficult to measure in real-time, which means reactor operation is typically based on experience and past measurements.In this project, we will implement an innovative bioelectrochemical sensor to monitor VFA uptake in real-time.

This information will be used to control the duration of pre-hydrolysis of the influent or the anaerobic feeding period of the AGS.

We expect that the innovative control strategy will ensure stable reactor performance, eliminate the need for external chemicals, and minimize energy requirements and climate impact of the process. The control strategy will be tested in pilot-scale reactors at Gryaab and implemented in full-scale.

It will also be tested by other wastewater treatment plants in Sweden, and we will use Chalmers innovation support system for commercialization and further dissemination of project results.