Improving biogas production from microalgae by enzymatic pretreatment.
Fabiana Passos, Andrea Hom-Diaz, Paqui Blanquez, Teresa Vicent, Ivet Ferrer
Author Information
Fabiana Passos: GEMMA - Environmental Engineering and Microbiology Research Group, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya·BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain; Environmental and Chemical Technology Group, Department of Chemistry, Universidade Federal de Ouro Preto, 35400-000 Ouro Preto, Minas Gerais, Brazil.
Andrea Hom-Diaz: Department of Chemical Engineering, Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola, Barcelona, Spain.
Paqui Blanquez: Department of Chemical Engineering, Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola, Barcelona, Spain.
Teresa Vicent: Department of Chemical Engineering, Universitat Autònoma de Barcelona, 08193 Bellaterra, Cerdanyola, Barcelona, Spain.
Ivet Ferrer: GEMMA - Environmental Engineering and Microbiology Research Group, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya·BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain. Electronic address: ivet.ferrer@upc.edu.
In this study, enzymatic pretreatment of microalgal biomass was investigated under different conditions and evaluated using biochemical methane potential (BMP) tests. Cellulase, glucohydrolase and an enzyme mix composed of cellulase, glucohydrolase and xylanase were selected based on the microalgae cell wall composition (cellulose, hemicellulose, pectin and glycoprotein). All of them increased organic matter solubilisation, obtaining high values already after 6h of pretreatment with an enzyme dose of 1% for cellulase and the enzyme mix. BMP tests with pretreated microalgae showed a methane yield increase of 8 and 15% for cellulase and the enzyme mix, respectively. Prospective research should evaluate enzymatic pretreatments in continuous anaerobic reactors so as to estimate the energy balance and economic cost of the process.
