Circular economy: Bridging the gap between phosphorus recovery and recycling

Abstract

Circular economy for nutrients! How to transfer buzzwords into solid results? So far the potential to recover and recycle phosphorus remains untapped or is just inefficiently used as in the case of sewage sludge, manure and food waste. To provide alternatives to argued traditional nutrient recycling routes, various technical solutions have been developed in recent years. They allow recovery of phosphorus minerals suitable as raw material for industries like fertilizer production or even as ready-to-use renewable or next-generation fertilizer. This contribution focuses on mineral phosphorus-containing materials recovered from wastewater. It discusses legal aspects and market opportunities regarding their valorization in Europe. It has to be kept in mind that there are many other recovery/recycling options out there to allow sustainable nutrient management, especially when it comes to organic wastes and their recycling. A frequently updated inventory is provided on the European Sustainable Phosphorus Platform's website (http://www.phosphorusplatform.eu/). The current revision of the European fertilizer regulation within the European Commission's circular economy package provides a concrete example, what issues have to be coped with and what measures have to be taken to create a level playing field for both primary- and secondary-based materials destined for fertilizer use. Some EU member states have started to enforce phosphorus recovery from relevant wastes but are lagging behind in enabling efficient recycling, be it in mineral or organic form. Still, the so-called technical nutrient recovery is missing a demand-side driven market pull for recovered (secondary) nutrients and the biggest challenge will be bridging the gap between supply (recovery) and demand (recycling), especially when it comes to new types of materials or products, not already established on the market. Whereas in the past, the focus of nutrient recovery technologies was laid upon high recovery rates for single nutrients, now energy efficiency, synergies and cost become more and more important. What about value chains? We have to look for easy to implement rather integrative solutions instead of reinventing the wheel, creating fancy parallel (infra)structures.