New technology boosts phosphorus recycling

Three plants recovering phosphorus from incinerated sewage sludge are being planned for Germany, Denmark and Sweden.

Danish engineering specialist COWI has been commissioned by EasyMining to develop facilities that will use the latter’s innovative technology, Ash2phos, to retrieve phosphorus from the incineration process of energy-from-waste plants. It is estimated that 25% of waste phosphorus goes to energy recovery. Ash is treated in a wet chemical process to recover phosphorus, aluminium and iron as clean commercial products.
‘The process for recovering phosphorus has been developed over a long period, and our partnership with COWI means that, with their help, we can now exploit our invention on a large scale,’ says Jan Svärd, ceo of EasyMining, which is based in Uppsala Sweden.

Environmental benefit

The need for such recycling received backing in a 2016 academic report into three primary phosphorus waste streams (human food waste, human excreta, and animal manure) and how they could be applied to corn production. The study found that just 37% of the phosphorus available in existing waste streams could support the annual phosphorus requirements of the entire US corn crop.
The new plants will help reduce the need for phosphorus mining and ease the environmental impact of such mining. The project is seen as a major step towards sustainable food production. The Swedish plant, for example, will have the capacity to supply 25% of the country’s demand for the mineral.

Operational by 2020

‘We are very dependent on phosphorus for our food production. But the Earth’s resources are finite, and the need to recover phosphorus is growing all the time,’ says Anna Berggren, who is head of bioenergy at COWI. ‘Being involved in developing this together with EasyMining while also tackling environmental problems makes this project incredibly exciting.’
COWI and EasyMining, a subsidiary of Ragn-Sells, have been working together on the development phase for two years. The first production facility is scheduled to go into operation in 2020.