Farm2Export: Ammonia. Farm2Export Guidance Document Series.

The Farm2Export project, launched in 2023 under the Sustainable Utilisation of Livestock Slurry programme and partly funded by the Department of Agriculture, Environment and Rural Affairs (DAERA), is developing an integrated nutrient recovery system for Northern Ireland.

This system combines on-farm slurry management with processing at anaerobic digestion plants to recover and redistribute nutrients efficiently. At the farm, a mobile screw press is used to separate slurry into a liquid fraction, which remains on site and supports the use of Low Emission Slurry Spreading Equipment (LESSE), and a dryer, solid fraction, which is transported to anaerobic digestion facilities. After anaerobic digestion, the resulting digestate is further separated and dried to remove additional liquid. This secondary liquid can also be applied locally as a nutrient source, while the dried solid digestate is processed into a bio-based fertiliser with concentrated stabilised nutrients that can be easily exported from nutrient-rich areas.

The purpose of this report is to:

• Model the Farm2Export process by tracking material flows through the nutrient supply chain, to determine the scale of biomass recovery required to supply one bio-based fertiliser plant.
• Quantify ammonia emissions across the entire supply chain relative to conventional manure and digestate management practices.
• Discuss the potential challenges and opportunities associated with the deployment of the Farm2Export nutrient recovery supply chain.

This report is intended to be useful for policymakers, regulators, researchers and stakeholders in agriculture and environmental management, providing evidence and guidance on nutrient recovery and sustainable manure management.