title: Modelling a demand driven biogas system for production of electricity at peak demand and for production of biomethane at other times.
abstract: Four feedstocks were assessed for use in a demand driven biogas system. Biomethane potential (BMP) assays were conducted for grass silage, food waste, Laminaria digitata and dairy cow slurry. Semi-continuous trials were undertaken for all feedstocks, assessing biogas and biomethane production. Three kinetic models of the semi-continuous trials were compared. A first order model most accurately correlated with gas production in the pulse fed semi-continuous system. This model was developed for production of electricity on demand, and biomethane upgrading. The model examined a theoretical grass silage digester that would produce 435kWe in a continuous fed system. Adaptation to demand driven biogas required 187min to produce sufficient methane to run a 2MWe combined heat and power (CHP) unit for 60min. The upgrading system was dispatched 71min following CHP shutdown. Of the biogas produced 21% was used in the CHP and 79% was used in the upgrading system.
authors.affiliation: MaREI Centre, Environmental Research Institute (ERI), University College Cork (UCC), Ireland; School of Engineering, UCC, Ireland.
authors.forename: R
authors.initials: R
authors.lastname: O'Shea
authors.affiliation: MaREI Centre, Environmental Research Institute (ERI), University College Cork (UCC), Ireland; School of Engineering, UCC, Ireland. Electronic address: david.wall@ucc.ie.
authors.forename: D
authors.initials: D
authors.lastname: Wall
authors.affiliation: MaREI Centre, Environmental Research Institute (ERI), University College Cork (UCC), Ireland; School of Engineering, UCC, Ireland.
authors.forename: J D
authors.initials: JD
authors.lastname: Murphy
mesh_terms: D000818:Animals; D056804:Biofuels / Q000032:analysis; D001709:Biotechnology / Q000295:instrumentation / Q000379:methods*; D002417:Cattle; D003612:Dairying; D004560:Electricity; D005260:Female; D005502:Food; D007700:Kinetics; D007795:Laminaria; D008372:Manure; D008697:Methane / Q000096:biosynthesis*; D008962:Models, Theoretical; D006109:Poaceae; D012820:Silage; D018505:Waste Management / Q000295:instrumentation / Q000379:methods
chemical_list: D056804:Biofuels; D008372:Manure; D008697:Methane
keywords: Biomethane; Demand driven biogas; Food waste; Grass silage; Renewable energy