title: Environmental assessment of nutrient recycling from biological pig slurry treatment--impact of fertilizer substitution and field emissions.
abstract: Pig slurry treatment is an important means in reducing nitrogen loads applied to farmland. Solid phase separation prior to biological treatment further allows for recovering phosphorus with the solid phase. The organic residues from the pig slurry treatment can be applied as organic fertilizers to farmland replacing mineral fertilizers. The environmental impacts of nutrient recycling from aerobic, biological pig slurry treatment were evaluated applying the life cycle assessment (LCA) methodology. LCA results revealed that direct field emissions from organic fertilizer application and the amount of avoided mineral fertilizers dominated the environmental impacts. A modified plant available nitrogen calculation (PAN) was introduced taking into account calculated nitrogen emissions from organic fertilizer application. Additionally, an equation for calculating the quantity of avoided mineral fertilizers based on the modified PAN calculation was proposed, which accounted for nitrogen emissions from mineral fertilizer application.
authors.affiliation: INRA, UR050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne, F-11100, France. Electronic address: doris.brockmann@supagro.inra.fr.
authors.forename: Doris
authors.initials: D
authors.lastname: Brockmann
authors.affiliation: INRA, UR050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne, F-11100, France.
authors.forename: Mary
authors.initials: M
authors.lastname: Hanhoun
authors.affiliation: INRA, UR050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne, F-11100, France.
authors.forename: Ophélie
authors.initials: O
authors.lastname: Négri
authors.affiliation: INRA, UR050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne, F-11100, France; Montpellier SupAgro, 2 Place Viala, 34060 Montpellier Cedex 1, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Hélias
mesh_terms: D000818:Animals; D005308:Fertilizers; D008372:Manure; D019216:Metals, Heavy / Q000032:analysis; D009589:Nitrogen Oxides / Q000032:analysis; D013552:Swine
chemical_list: D005308:Fertilizers; D008372:Manure; D019216:Metals, Heavy; D009589:Nitrogen Oxides
keywords: Field emissions; Life cycle assessment; Mineral fertilizer equivalent; Nutrient recycling; Pig slurry treatment