Europe produces 50 million tons
of sewage sludge per year
We shower, flush our toilets and wash our dishes every day. But what happens to all that wastewater after it's discharged into the sewer system? It ends up in sewage treatment plants, where it is purified.
Millions of tons of sewage sludge are left behind.
Due to the use of phosphorus as a fertilizer in agriculture, it is present in high concentrations in the wastewater and thus in the sewage sludge. In addition, there are also various environmental toxins (e.g. heavy metals such as copper and zinc, pharmaceutical residues, microplastics, etc.). At EU and national level, new directives and regulations are therefore intended to restrict the direct agricultural use of sewage sludge in the future.
The alternative is incineration, but this also involves burning the valuable phosphorus. Several new regulations aim to ban "complete incineration" and require the recovery of the phosphorus. Operators of wastewater treatment plants are therefore challenged to find new ways to dispose of sewage sludge and to ensure that the phosphorus is recovered.