Montingelli
Dublin City University, Ireland
Title: Optimization of mechanical pretreatment and organic concentration of brown seaweed for methane production
Biography
Biography: Montingelli
Abstract
Recently, the European Commission has opened a discussion about limiting first generation food based biofuels in favour of advanced biofuels, such as those sourced from seaweed. It has been proposed to set at least at 2.5% of renewable energy supply in transport (RES-T) the use of this kind of biofuels. The main reason is to limit the broad uncertainty in estimates of indirect land use change (ILUC) emissions. In this context, brown seaweed represent a valuable solution as they lack of lignin and have low cellulose content, thus they are particularly suitable for degradation processes such as anaerobic digestion (AD). The biogas produced through AD can then be upgraded to biomethane, which can be introduced into the gas grid or used as a transport fuel. Brown seaweed such as Laminaria spp. and Ascophyllum nodosum were co-digested with digested sewage sludge at a mesophilic temperature of 38°C and for a retention time of 14 days. The effects of a beating pretreatment in terms of pretreatment time (5-10-15 min) and changes in the volatile solids (VS) concentration (1-2.5-4%) from seaweed on methane production were investigated through a response surface methodology (RSM). Laminaria spp. showed a maximum methane yield of 272 mL CH4 g-1 VS when the pretreatment time was set at 10 min and a VS concentration of 2.5% was used. In the case of Ascophyllum nodosum, the best yield of 169 mL CH4 g-1 VS was found at the maximum pretreatment time tested of 15 min and at the minimum concentration of VS.