CHAR RIMEDIO: Use of biochar to reduce ammonia and GHG emissions from pigs livestock

The introduction of biochar from gasification in the livestock effluent management chain is interesting for the valorisation of biochar in agriculture as a soil improver enriched in N, P and micronutrients, thanks to the interaction with pig slurry and as a means to sequester CO2 in the soil . The application of biochar to pig slurry contributes to reducing the carbon footprint only if the subsequent valorisation in the field is considered. Theses with biochar field application allow to sequester more CO2 in the soil than they emit in the analyzed process: -8352 kg CO2eq/ha (FiltChar), - 8597 kg CO2eq/ha (AeroChar), -15433 kg CO2eq/ha (MatChar) and +7830 kg CO2eq/ha for control. The most suitable solution in reducing ammonia emissions is the covering of the pig slurry storage by MatChar solution which reduces emissions by 32% compared to uncovered storage. The AeroChar N/DN biological treatment was effective in reducing methane and nitrous oxide emissions (-17% and -10% respectively) compared to the control. Slurry filtration by biochar (FiltChar) is less promising in mitigating emissions. After interaction with pig slurry, biochar is more suitable for subsequent agronomic use for fertilizing purposes (pH, C/N and TOC) and the N and P content is significantly increased. The critical point for large-scale development is the availability of biochar on the market and the high price due to the still undeveloped production chain. The economic sustainability of the biochar application could become positive if the procurement price fell to €80/t.