New Life for Biowaste as a sustainable Soil Improver

With a share of 34 %, bio-waste is the largest single component of municipal waste in the EU. Recycling of bio-waste is key for meeting the EU target to recycle 65 % of municipal waste by 2035.

Bio-waste can significantly contribute to a more circular economy, delivering valuable soil-improving material and fertiliser as well as biogas, a source of renewable energy.

Biochar is a pure, high carbon form of charcoal, obtained through the pyrolysis of biomass, such as bio-waste. Biochar helps regenerate soils by enhancing water-holding capacity, nutrient uptake, soil fertility stimulating microbial activity and diversity and acts as a carbon sink.

However, a lack of understanding and evidence of the agronomic benefits and economic returns mean that biochar faces barriers to become a widespread soil improver.

Biogas from anaerobic digestion (AD) is a renewable energy source. Yet the cost of disposal of its effluents (digestates) reduces profitability and uptake of new AD projects, even though the digestate is rich in nutrients and can be used as a biofertilizer.

Research shows that the combination of digestate and biochar creates a biofertilizer with increased fertility, improved stability and excellent soil regeneration properties. Furthermore, biochar could be a powerful additive to enhance microbiological activity in AD plants.

The FENIX project will optimise Biochar for different soils using AD digestate. FENIX will demonstrate the agronomic and economic returns of its soil improver in field tests (TRL 8) in three countries in the West and South of Europe. FENIX brings together partners that cover the full value chain and with entrepreneurs that will be ready to take up the project results.

Successful completion of the project will contribute to the recovery of abandoned poor soils, increase EU’s soil quality and water retention capacity, climate change mitigation, secure and independent energy supply, and sustainable bio-waste management.