Close this search box.


Topic "Nutrient recovery processes (N and P)"

A few words

Nutrient recovery processes for Nitrogen and Phosphorus

Nutrient recovery from wastewater is a major challenge to improve the sustainability of our wastewater management systems and to produce fertilizers for bio-based food products. This is all the more necessary as the traditional production of nitrogen fertilizers is energy intensive, and phosphorus is a non-renewable mining resource.

The SYMBIOSE team develops innovative processes to transform mineral forms into a valuable form and extract them at acceptable costs. Our ambition is to obtain processes with low energy requirements and reduced environmental impacts.

We work with sludge from biological treatment plants, digestates from anaerobic digestion, or specific effluents such as urine.

The transformation of wastewater treatment plants into resource recovery plants is studied both for metropolises (Paris and the MOCOPEE program) and for small and medium-sized wastewater treatment plants in rural areas (collaboration with Réseau31). Our approach aims to equip current small wastewater treatment plants with specific automatic control solutions to reduce costs, and to consider centralized recovery solutions.

Ongoing projects

OMIX Project


Fractionation of digestates into irrigation water and renewable fertilizers for a sustainable methanization.

The project is a winner of the GRAINE call for projects from ADEME and is co-financed by the Occitanie Region. The challenge of the project is to propose the experimental development and the demonstration of a total transformation of digestates, coming from a methanization site treating mainly biowaste, to obtain on the one hand various fertilizers (organic, organo-mineral, mineral) ensuring the return of nutrients to the soils, and on the other hand water for irrigation or reuse, at a territorial scale. The technical demonstration of the OMIX system will be carried out by the company CLER-VERTS, the company NEREUS and the laboratory TBI. The work carried out within the team is focused on transmembrane chemosorption (TMCS). This innovative and promising technology can be applied to digestate supernatants and urine from source separation (DESIGN project) where this technology is combined with phosphorus recovery by struvite precipitation.)



This project is financed by the SIAAP via the MOCOPEE research and innovation program. The aim is to develop phosphorus recovery processes in wastewater treatment plants in which iron salts are used.

The work includes (1) an analysis of the speciation of phosphorus and iron in sludge (2) an analysis of the kinetics of biological reduction of iron under anaerobic conditions, (3) a study of iron phosphate (vivianite) recovery processes.

CircRural 4.0


Winner of the Interreg Sudoe call for projects, the project brings together international actors from Spain, Portugal and France with the main challenge of undertaking the conversion of small and medium-sized wastewater treatment plants (WWTP) in rural areas into facilities for resource recovery. The axis of the project developed in the team consists of building automatic control algorithms for the optimization of phosphorus removal and energy consumption in small and medium-sized wastewater treatment plants.

DESIGN Project


The DESIGN project is funded by the French National Research Agency (ANR) on the main societal challenge: Mobility and sustainable urban systems. It aims to develop and evaluate innovative scenarios for source separation and wastewater recovery. The challenge of the project is to evaluate the real benefits and constraints of these alternative approaches by integrating different criteria:

  • on the environmental level, by evaluating the different solutions through life cycle analysis;
  • d’un point de vue technologique et économique : en développant des technologies clés pour les nouvelles filières, i.e. des toilettes à séparation sous vide qui n’existent pas actuellement, une nouvelle technologie de récupération de l’azote ammoniacal pour produire un fertilisant ;
  • from a sociological point of view, by measuring the capacity of appropriation of these new devices of management of human discharges and decentralized systems by the communities, the users and the professionals of the urban environment;
  • finally, from an urban planning point of view, by assessing the suitability of source separation scenarios for different urban typologies.

The DESIGN project brings together two research laboratories, two design offices specialized in the environment, and two companies developing innovative equipment.