Recovery of fertilizer nutrients from materials - Contradictions, mistakes and future trends

Highlights: • The transition from the take-make-use-dispose linear to the circular economy through valorization of secondary raw materials enhances resource efficiency. • Sustainable development should embrace recovery of both materials and energy from optimised separate-municipal collection systems. • Plant-derived waste (biomass) reuse reduces dependence on fossil resources. -- Abstract: In circular economy an effective strategy with regard to material valorization for fertilizers is expected to substantially improve sustainability, save resources and offer significant environmental, social and economic benefits. Wastes – especially biomass – are a large reservoir of materials which can be recovered via different technologies and used for manufacturing various fertilizers. Increasing re-use of nutrients from waste biomass is very difficult and requires taking additional steps to effectively use the potential of waste. It is necessary to introduce selective waste collection, increase the efficiency of nutrient recovery, obtain a more concentrated form with good bioavailability. Biomass waste streams carry huge potential, the content of fertilizer components is estimated at approx. 22 million Mg/year for nitrogen and 1.3 million Mg/year for phosphorus. Waste streams with the highest potential are waste from the food chain, manure and sewage, which are further processed and can be used for the production of fertilizers. Further research and experiments should be done to develop technologies that will enable exploitation of materials of high added value from biomass. Careful consideration should be given to energy routes. There is an urgent need for new technologies with which stable market dynamics via new business models could be safeguarded.