Goal
- Agriculture: Cut GHG, Boost Yield via nitrification of Biogas Digestate
- Demonstrate nitrification of digestate converts ammonium to a nitrate fertilizer
- Validate elimination of ammonia evaporation and indirect N₂O emissions from nitrate fertilizer
- Prove 20% increased crop yields through more efficient plant uptake of nitrogen and sulfate
- Quantify scalability and sector climate impact for agriculture by 2030
Plan
- Run continuous, automated nitrification on digestate at Rybjerg Biogas to confirm stable
ammonium → nitrate conversion at two 10 m³ tanks. - Optimize oxygen dissolution, foam control, pH regulation, and dry-matter removal using improved MBBR tank design and efficient O₂ dissolving methods.
- Produce 3 nitrate fertilizer products (NO₃, PKNO₃, +50 NO₃-N) for agronomic tests.
- Measure nutrient/carbon mass balances, quantify GHG impact, validate economics, and present results to agriculture and biogas stakeholders to prove scalability and 2030 climate potential.
Expected results
- 200 L/h throughput with >95% NH₄→NO₃ conversion over continuous automated operation
- Prove near-zero ammonia evaporation and reduced indirect N₂O from the nitrate fertilizer
- 25% higher grass yields and nitrogen-use efficiency from nitrate fertilizer vs untreated digestate.
- Verified climate impact, if the technology is used at biogas digestate in agriculture by 2030