Full-scale production of mineral concentrates from pig slurry using reverse osmosis

摘要: When the amount of livestock manure on land is legally limited by phosphate many farmers will have to apply additional nitrogen meet need for optimal crop production. The use chemical fertilizer can be reduced if recovered from surplus. This paper presents results two years monitoring 5 full-scale processing plants production mineral concentrates that are used replace fertilizer. process includes chemo-mechanical separation and reverse osmosis as final step. streams treatment involved in were monthly sampled contents total solids, volatile solids main nutrients measured. Results showed studied a reliable performed at farm-scale well regional scale. A concentrate constant quality produced managed. observed differences composition between explained raw slurry operational management process, especially concerning applied cleaning regime. RO-concentrates qualified nitrogen-potassiumfertilizer with average concentrations 7.1 g/kg N 7.8 K. Nitrogen present mainly ammonia (90-95% N) which implies risk loss evaporation during after spreading.