Carbon balance and energy potential for a novel wastewater treatment process

Municipal wastewater treatment plants (WWTPs) are facing stricter effluent requirements expected from the future EU wastewater directive. Meanwhile, it is desirable to decrease the utilization of resources and energy.

Background

A novel process for biological wastewater treatment called CELLA™ is being developed, where microorganisms grow as biofilm on bio-based carriers and remove organics and nutrients from the wastewater. It can be applied for both enhanced biological nitrogen and phosphorus removal. The influent wastewater composition and its content of easily degradable organics is important for a well-functioning denitrification (nitrogen removal) and enhanced biological phosphorus removal (EBPR).

In the ongoing pilot project FramBliK, VA SYD, Sweden Water Research and AnoxKaldnes (Veolia Water Technologies) combine a novel pre-treatment with the CELLATM technology to further enhance the process, and to minimise the use of both energy and chemicals. The pilot is operated at Källby WWTP (Lund). A post-treatment for the effluent from the biological nutrient removal is needed to capture particles, and to precipitate remaining phosphate. The organic particles which are removed in the pre-treatment and post-treatment contain chemical energy and can be used for biogas (methane) production through anaerobic digestion. The energy potential and the environmental gain for the wastewater treatment is greatly improved if more organics can be turned into energy and replace fossil fuels.

Objectives

The aim is to evaluate the biomethane potential in the pre- and post-treatments, and to give an overview of the carbon balance and energy potential of the novel wastewater treatment.

Method

Since the post-treatment is not included in the pilot plant, it will be tested in the lab through experiments with flocculation and filtration in a parallel master thesis project “Post-treatment for a novel wastewater treatment process”. The two projects can be done in cooperation and with synergy between the studies, since the separated particles in the post-treatment study can be used for bio-methane potential measurements in this master thesis. The experimental work on methane potential is combined with calculations of the carbon balance, which also includes the carbon utilisation for denitrification and biological phosphorus removal in the CELLA process. The work will be carried out in Lund, both at AnoxKaldnes and at VA SYD.

Interested to perform this master´s thesis? Please contact:

Maria Piculell, AnoxKaldnes, maria.piculell@veolia.com
Elin Ossiansson, VA SYD, elin.ossiansson@vasyd.se

Learn more about the project here.

FramBliK – The future biofilm process, still with continuous operation