title: The effect of trace element addition to mono-digestion of grass silage at high organic loading rates.
abstract: This study investigated the effect of trace element addition to mono-digestion of grass silage at high organic loading rates. Two continuous reactors were compared. The first mono-digested grass silage whilst the second operated in co-digestion, 80% grass silage with 20% dairy slurry (VS basis). The reactors were run for 65weeks with a further 5weeks taken for trace element supplementation for the mono-digestion of grass silage. The co-digestion reactor reported a higher biomethane efficiency (1.01) than mono-digestion (0.90) at an OLR of 4.0kgVSm(-3)d(-1) prior to addition of trace elements. Addition of cobalt, iron and nickel, led to an increase in the SMY in mono-digestion of grass silage by 12% to 404LCH4kg(-1)VS and attained a biomethane efficiency of 1.01.
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; School of Engineering, University College Cork, Cork, Ireland; Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Dunsany, Co. Meath, Ireland.
authors.forename: David M
authors.initials: DM
authors.lastname: Wall
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; School of Engineering, University College Cork, Cork, Ireland.
authors.forename: Eoin
authors.initials: E
authors.lastname: Allen
authors.affiliation: Department of Agricultural, Food and Environmental Science, Perugia University, Perugia, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Straccialini
authors.affiliation: Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Dunsany, Co. Meath, Ireland.
authors.forename: Padraig
authors.initials: P
authors.lastname: O'Kiely
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; School of Engineering, University College Cork, Cork, Ireland. Electronic address: jerry.murphy@ucc.ie.
authors.forename: Jerry D
authors.initials: JD
authors.lastname: Murphy
mesh_terms: D001421:Bacteria, Anaerobic / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D008372:Manure / Q000382:microbiology; D008697:Methane / Q000378:metabolism*; D006109:Poaceae / Q000382:microbiology*; D012037:Refuse Disposal / Q000379:methods; D012820:Silage / Q000382:microbiology*; D014131:Trace Elements / Q000378:metabolism*
chemical_list: D008372:Manure; D014131:Trace Elements; D008697:Methane
keywords: Biogas; Grass silage; Slurry; Trace elements