wastewater purification creates a greener water circuit

25.05.2021

EasyMining, an innovation company in the Ragn-Sells Group, is part of an EU LIFE-funded project aiming to develop a new, innovative purification and recovery process that removes ammonium nitrogen from wastewater. Following purification, the ammonium nitrogen is recovered and used as fertilizer. COWI assists EasyMining with detailed design of the mobile pilot plant, which will be put to work outside Stockholm, Sweden, and Copenhagen, Denmark.

Late February, the detailed design of LIFE RE-Fertilizer began – a R&D project headed by EasyMining which aims to remove ammonium nitrogen from wastewater. The technology enables a greener circuit by recovering ammonium nitrogen to use as fertilizer.

The advantages of this method are that it can prevent overfertilization while offering a circular process. The project will result in a pilot plant that is energy-efficient, resource-efficient and climate-friendly.

“It’s a rather challenging project since we have to carry out detailed design, in all disciplines, for a pilot-scale plant on very limited space and within a short timeframe of six months. In such a project, our close cooperation with COWI is absolutely important,” says Ruben Marshall, Lead Mechanical Engineer with EasyMining and Technical Project Manager of RE-Fertilize.

The technology targets water treatment plants among others, and it is attracting vast interest. As technical consultant, COWI provides detailed design in all disciplines such as process, piping, electrical and instruments as well as construction.

“This is an exciting project where participants representing a range of disciplines get to work closely together with a very knowledgeable and committed customer. We also contribute to increasing resource recovery and the green transition, which is an added bonus,” says Annelie Albertsson, Project Manager with COWI's Industry unit.

MOBILE PILOT PLANT

The project will result in a mobile pilot plant, which will initially be located at Ragn-Sell’s landfill Högbytorp outside Stockholm at the end of 2021, where it will be used to purify landfill leachate. Early 2022, the facility will be moved to Denmark, to the BIOFOS wastewater treatment plant where it will remove ammonium nitrogen from reject water resulting from the sludge dewatering before returning the water to the main outflow.

The RE-Fertilize project will also verify the suitability of nitrogen products generated in the process, such as fertilizer. On this part of the project, EasyMining had teamed up with Swedish agricultural cooperative Lantmännen.

The technology is expected to be ready for commercial use in the autumn of 2022, following assessment of the pilot runs and any improvement of the process.