Effect of Hydrothermal Pretreatment for Enhanced Biogas Production Using Micro-algal Biomass

Abstract

The filamentous algal biomass, Hydrodictyon reticulatum (H. reticuatum) was used to evaluate the biogas production after hydrothermal pretreatment in batch anaerobic digestion. The effect of hydrothermal pretreatment at range of 50 ~ 280 o C was tested with filamentous algal biomass. The solubilization by pretreatment showed a higher degree of disintegrated filamentous algal biomass and the soluble COD was increased 12.8 fold than untreated sample at 280 o C. Solubilization due to hydrothermal pretreatment increased the specific biogas production and volatile solids reduction rates. Using the hydrothermal treatment approach, the specific methane production were 161.8, 169.1, 178.4, 191.7, 274.9, 285.2 and 364.4 mL/g-VS of the pretreated at raw, 50, 100, 120, 180, 230, and 280 o C, respectively. The volatile solids reduction was greater with increased temperature applied, and the degradation increased 69.7% at 280 o C from 45.8 % VS reduction of raw filamentous algal biomass.