23 May 2024| EasyMining and Gelsenwasser, partners in the joint venture Phosphorgewinnung Schkopau GmbH (PGS), have committed to a significant investment to establish world’s first plant for phosphorus recovery based on the Ash2Phos technology in Schkopau, Germany. The plant is scheduled to start operations in early 2027.
According to the partners, the plant represents a paradigm shift in phosphorous technology.
“At EasyMining, we view the establishment of the first plant for phosphorus recovery based on our Ash2Phos technology, as a great opportunity to pioneer circular solutions for essential nutrients like phosphorus”, says Christian Kabbe, Managing Director at Phosphorgewinnung Schkopau and EasyMining Germany.
With a targeted capacity of 30,000 tonnes of sewage sludge ash annually, equivalent to 10% of Germany’s current sewage sludge ash volume, the new facility will play a pivotal role in securing a stable and locally sourced supply of high-quality phosphorus within Europe.
The Ash2Phos technology, developed by EasyMining, boasts an impressive phosphorus extraction rate exceeding 90% from the ash of incinerated sewage sludge. Furthermore, the plant will not only recover phosphorus but also yield valuable co-products including ferric chloride, sodium aluminate, and sand, positioning them as indispensable commodities crucial for various societal applications.
The principle of phosphorous recycling according to the Ash2Phos process
Ash from the mono-combustion of dried sewage sludge serves as feed material. It contains about 7 – 10 % phosphorous, 10 – 15 % iron and 1,-10 % aluminum. In the first of three treatment steps acid (HCl) is added to cause chemical digestion of the ash. The acid reaction is followed by a separation step to remove non-soluble residues. The valuables phosphorous, iron an aluminum remain in the solution, so they are available to be recovered as Calciumphosphate, iron hydroxide and aluminum hydroxids in a second, caustic reaction step with lime. In a third refining step these intermediates are converted to phosphoric acid and super phosphate, iron chloride and aluminum sulfate and aluminum chloride respectively. In all, recovery rates of 90 – 95 % for phosphorous, 60 – 80 % for aluminum and 10 – 20 % for iron can be achieved.
process details