Resource-Efficient Removal of Nutrients from Wastewater in Cold Climate

Many treatment plants in northern Sweden are facing a major challenge when nitrogen removal requirements are being updated, new goals for climate neutrality and separation of micropollutants are introduced and wastewater volumes are expected to rise as a result of the ongoing industrialization. The availability of chemicals for phosphorus precipitation is also uncertain in future.

Wastewater treatment plants in northern Sweden may need to be rebuilt from scratch to meet these challenges.

This offers a possibility to choose efficient and resource-efficient process solutions that reduce dependency on chemicals, minimize climate impact and increase the possibilities for nutrient recovery.

The goal of the project is to design a resource-efficient wastewater treatment process with low climate impact adapted to Norrland conditions with periodically cold water temperatures.

The project will focus on testing technical solutions for wastewater treatment from nitrogen and phosphorus, modeling these processes as well as optimization for resource efficiency, reduction of nitrous oxide emissions and removal of pharmaceutical residues.

The project will also look at nutritional conditions in the Gulf of Bothnia to motivate for what level of treatment is reasonable to target.

The process solution studied in the project consists of biological phosphorus and nitrogen removal in moving bed biofilm reactors (MBBR) combined with hydrolysis of primary sludge for internal carbon source production.