From waste to field: LANDFEED advances bio-based fertilizer innovation across five European use cases

As the LANDFEED project marks its second year, the consortium reports substantial advances across its five use cases. LANDFEED is developing innovative solutions to produce bio-based fertilisers and bio-stimulants from diverse organic waste streams, contributing to a more circular and sustainable approach to nutrient management in European agriculture. 

Spain: From Catering Waste to Crop Nutrition 

In Spain, the team led by AZTI, together with AUSOLAN, KOLLVIK FR, and FERTINAGRO, has demonstrated that waste from hotels, restaurants, and catering (HORECA) can be converted into high-quality fertiliser ingredients through an optimised solid-state fermentation process. Pilot trials revealed enhanced protein and amino acid content, improved mineral availability, and a significant reduction in the Carbon/Nitrogen ratio, all of which increase the agronomic value of the resulting product. Semi-industrial systems are currently under development, and further pilot and field trials will validate the scalability and performance of the process. 

France: Converting Animal Waste into a Zero-Waste Fertiliser Process 

The French use case focuses on converting a mix of undervalued animal waste, from fish farming, the shellfish industry, sheep breeding, and slaughterhouses, into bio-based fertilising products with balanced agronomic compositions. An optimised sequence of twin-screw extrusion and enzymatic hydrolysis transforms these mixed streams into three distinct outputs: a high-value fish oil, a liquid bio-stimulant, and a solid organic fertiliser, achieving a zero-waste process. During the first 24 months, the input materials were selected, collected, and characterised, and the process was successfully developed and optimised from laboratory scale to near-commercial scale. A field trial on wheat is currently ongoing to assess the agronomic efficiency of the resulting bio-based fertiliser, and the quality of the fish oil has already been recognised. The approach contributes to strengthening the European fertiliser value chain whilst complying with the EU Fertilising Products Regulation (EU) 2019/1009. 

Greece: Unlocking the Potential of Olive Oil Residues 

In Greece, the use case focuses on the circular valorisation of olive oil mill residues through an integrated biorefinery approach. Over the first 24 months, the team completed extensive feedstock characterisation and process optimisation activities. The pilot-scale infrastructure at NTUA's Lavrion Technological and Cultural Park has been fully commissioned, integrating drying, biomass combustion, oil extraction, CO₂ capture, and algae cultivation units. Results demonstrated the potential to recover energy, bio-oil, nutrients, and carbon from two-phase olive pomace, producing nutrient-rich ash and algal biomass suitable for fertiliser applications. Greenhouse and field trials are planned for the next phase of the project. 

Italy: Industrial Symbiosis at the Heart of Fertiliser Innovation 

The Italian use case applies an output-based design approach to multi-waste bio-based fertilisers, combining diverse organic and inorganic streams, including wastewater sludge, agro-industrial residues, and volcanic ash through a territorial Industrial Symbiosis model. During the first 24 months, the team sourced and characterised all input matrices, assessed regulatory, logistical, and stakeholder aspects, and tested pretreatment routes, primarily composting at an industrial facility. Bio-augmented formulations are now being developed using selected microbial consortia to enhance agronomic performance. Pot trials and field trials are ongoing to identify the most effective and sustainable final formulations. 

Poland: From Dairy Waste to Bio-stimulants and Granular Fertilisers 

In Poland, the team is valorising dairy waste into a bio-based solid organo-mineral fertiliser and a liquid bio-stimulant. Following detailed characterisation of the raw material, chemical hydrolysis processes were optimised to minimise nitrogen losses and increase the bioavailability of nutrients. The resulting products showed promising compliance with the EU Fertilising Products Regulation (EU) 2019/1009, and initial germination tests ruled out phytotoxic effects. Pot tests and field trials, conducted in collaboration with the Institute of Soil Science and Plant Cultivation (State Research Institute), are currently under way. Scaling-up activities are also in progress to prepare the technology for potential future implementation. 

Looking Ahead 

Together, the results from LANDFEED's use cases demonstrate that organic waste streams from catering leftovers to dairy residues and olive oil byproducts, hold significant potential as sources of plant nutrition. As the project moves into its next phase, the consortium will focus on validating formulations through field trials and preparing results for regulatory assessment and market uptake.