Biofertilisers with high nutrient and carbon retention capacity to accelerate circular bioeconomy

The overall objective of SoilBoost project is to produce a new type of nutrient- and carbon-rich biofertiliser, solely by recycling of organic waste, i.e. domestic animal slurry waste and forest-based residue biomass. In contrast to current chemical fertilisers’ production routes, the SoilBoost consortium wishes to completely avoid the use of fossil fuels (e.g. natural gas) and only use sustainable and locally sourced organic waste as feedstock. When applied to the soil, our biofertiliser’s high nutrient and carbon retention capacity can improve soil health and quality and boost crop growth yields more efficiently (up to 50% more) than today’s fertilisers, which suffer from high leaching losses of toxic elements. The latter entails that farms need to apply more fertilisers (double amount typically), hence further endangering soil health and leading to biodiversity decline, while wasting water unnecessarily. Regarding the latter, our biofertiliser has a microporous structure, which enables to retain water up to 50% more vs. conventional fertilisers and thus prevent overapplication of water to fields. The SoilBoost bioferiliser is biochar based with a nano-sized organic biofilm-amended surface that acts as a biofilter for the controlled adsorption of nutrients from feedstocks. The synthesis process is based on several related patents. The project is composed of a multi-actor project consortium covering the whole value chain, i.e., from local (“zero-km”) feedstock supply to fertiliser end-users/customer, that will demonstrate a pilot-scale production plant, located in Lleida (Spain), with 15 kilotons (kt) biofertiliser production capacity. Thanks to the avoidance of natural gas and utilisation of locally sourced organic feedstocks instead, as well as the deployment of low-power off-the-shelf equipment, SoilBoost can reduce the fertiliser production costs by ~41%, compared to today’s energy-intensive production processes, located mainly outside Europe.