Remondis Aqua: extracting phosphoric acids from sewerage sludge

Sewerage plant image
Type of organisation or company
Language for original content
Submitted by
Technopolis Group

Remondis Acqua Group is a company specialising in systems for the production of high-quality water. They have developed new methods to protect raw materials – and new ways to treat wastewater.

In order to do so, they have come up with a new model of municipal sewerage treatment plant. Their philosophy is to see sewerage treatment plants as places to recover clean water, energy and minerals. With their new method, the sewerage sludge ash is dissolved not in hydrochloric acid – the standard procedure – but in phosphoric acid. The phosphoric acid is enriched with the phosphorus contained in the ash and then processed in a number of different stages.

This procedure produces a number of final products including phosphoric acid, used in the production of phosphates (inc. fertilisers), gypsum for the building supplies trade, and iron and aluminium salts. These salts can be returned to the sewerage treatment plant to be used as a precipitating agent to treat wastewater and eliminate phosphorus. Overall, this is an efficient and cost-effective way to reclaim materials.

Main results
  • Helping recover the precious resources contained in sewerage sludge.
  • Reducing the amount of resources going to landfills.