title: Optimisation of substrate blends in anaerobic co-digestion using adaptive linear programming.
abstract: Anaerobic co-digestion of multiple substrates has the potential to enhance biogas productivity by making use of the complementary characteristics of different substrates. A blending strategy based on a linear programming optimisation method is proposed aiming at maximising COD conversion into methane, but simultaneously maintaining a digestate and biogas quality. The method incorporates experimental and heuristic information to define the objective function and the linear restrictions. The active constraints are continuously adapted (by relaxing the restriction boundaries) such that further optimisations in terms of methane productivity can be achieved. The feasibility of the blends calculated with this methodology was previously tested and accurately predicted with an ADM1-based co-digestion model. This was validated in a continuously operated pilot plant, treating for several months different mixtures of glycerine, gelatine and pig manure at organic loading rates from 1.50 to 4.93 gCOD/Ld and hydraulic retention times between 32 and 40 days at mesophilic conditions.
authors.affiliation: Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782 Santiago de Compostela, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: García-Gen
authors.affiliation: Institute Center for Water and Environment (iWater), Masdar Institute of Science and Technology, PO Box 54224, Abu Dhabi, United Arab Emirates. Electronic address: jrodriguez@masdar.ac.ae.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rodríguez
authors.affiliation: Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782 Santiago de Compostela, Spain.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Lema
mesh_terms: D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis
keywords: ADM1; Anaerobic co-digestion; Biogas; Linear programming; Optimisation