Dynamic effect of leachate recirculation on batch mode solid state anaerobic digestion: Influence of recirculated volume, leachate to substrate ratio and recirculation periodicity

• Published in: Bioresource technology Vol. 216; pp. 553 - 561
• Main Authors: Degueurce, Axelle, Trémier, Anne, Peu, Pascal
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2016; Elsevier
• Subjects: Anaerobiosis; Animals; Batch Cell Culture Techniques; Bioreactors; Cattle; Cattle manure; Environmental Sciences; Equipment Design; Experimental design; Leach bed reactor; Manure; Methane - biosynthesis; Methane production kinetics; Models, Theoretical; Waste Disposal, Fluid - instrumentation; Waste Disposal, Fluid - methods; Experimental design; Cattle manure; Leach bed reactor; Methane production kinetics; LEACH BED REACTORS; LEACH BED REACTOR; METHANE PRODUCTION KINETICS; LEACHATE RECIRCULATION; SUBSTRATES; CATTLE MANURE; BOS; CENTRAL COMPOSITE; THREE PARAMETERS; SOLID-STATE ANAEROBIC DIGESTIONS; DYNAMIC EFFECTS; METHANE; CATTLE MANURES; MANURES; EXPERIMENTAL DESIGN; FERTILIZERS; METHANE PRODUCTION; ANAEROBIC DIGESTION; DESIGN OF EXPERIMENTS
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2016.05.113

•The periodicity of leachate recirculation has the most influence during SSAD.•A long period without recirculation reduces moisture and therefore SSAD performance.•Volumes of recirculated leachate can counteract the effect of periodicity.•High L:S ratios dilute nutrients and metabolites.•Several recirculation practices lead to similar SSAD performances. Performances of batch mode solid state anaerobic digestion (SSAD) were investigated through several leachate recirculation strategies. Three parameters were shown to particularly influence methane production rates (MPR) and methane yields: the length of the interval between two recirculation events, the leachate to substrate (L:S) ratio and the volume of leachate recirculated. A central composite factor design was used to determine the influence of each parameter on methane production. Results showed that lengthening the interval between two recirculation events reduced methane yield. This effect can be counteracted by recirculating a large volume of leachate at a low L:S ratio. Steady methane production can be obtained by recirculating small amounts of leachate, and by lengthening the interval between two recirculations, regardless of the L:S ratio. However, several combinations of these parameters led to similar performances meaning that leachate recirculation practices can be modified as required by the specific constraints SSAD plants configurations.