Wastewater phosphorus recycling takes step forward
A pilot project to extract phosphorus from wastewater is underway in Denmark, which could open up commercial opportunities to recycle this increasingly scarce mineral.
The scheme involves a consortium of partners including Danish water authority, Aarhus Water, and Grundfos. It will seek to trial new technologies to recover the phosphorus, which already presents a problem as it forms deposits in wastewater pipes, causing blockages.
Aarhus Water has worked on removing phosphorus from wastewater since 2011, but the project only really gained speed when the utility firm discovered that a group in the US state of Oregon had made good progress on phosphorus recycling.
According to Aarhus Vand's department manager Claus Homann, extracting phosphorus from wastewater holds great potential.
"From our perspective, we can solve a problem and exploit an opportunity at the same time. We can avoid blockages in our pipes while extracting a valuable resource with commercial value - utilising a scarce resource in a sustainable manner at the same time," he said.
Vand believes the plant in Åby where the technology is being trialled can be developed to extract 60% of the phosphorus from wastewater.
The pilot scheme has the backing of the Danish government. Environment Minister Ida Auken said it was "an example of what green transition is all about".
"We develop solutions to environmental problems while also creating new products which can generate income in the future. Phosphorus discharge into the aquatic environment is not only a challenge in Denmark. It is a global problem, so there are great benefits in finding a method to solve it," he commented.
As one of the partners in the project, Grundfos will supply specialised components for phosphorus extraction in the form of dosing pumps, booster systems and control systems for the wastewater plant.