BIOETHANOL PRODUCTION FROM DRY ULVA LACTUCA ALGAE BY ALCOHOLIC FERMENTATION

This study focuses on alcoholic Sacharomyces cerevisiae yeast fermentation of suspensions from Ulva lactuca sp. powder, after the enzymatic hydrolysis of polysaccharides with Aspergillus niger cellulase. Bioethanol production from algae is a complex process, depending mainly on the content of fermentable sugars in the raw material. The drying process is an important step in treating fresh algae harvested from the sea, in order to prevent algae gelling. In order to investigate the effect of process factors, a 2(4) factorial experiment was designed. The effect of the following factors was studied: solid to liquid ratio (S = 1/12 and 1/24), cellulase ratio (U = 8 and 16 U/g d.m.), alcoholic fermentation temperature (t = 25 and 35 degrees C) and mean particle diameter (M = 304 and 1279 mu m). The mathematical model predicting the yield of volatile compounds (V) and ethanol (E) in g/g d. m. was obtained by regression.