ANAEROBIC BIODEGRADABILITY OF ALGAE

The objective of this research has been to study on a laboratory scale the anaerobic biological degradation of the algal biomass generated in a raceway-type reactor which could be used in the post-treatment of a UASB reactor. The research has had two stages. In the first the methodology for measuring the methanogenic activity of a biological culture from an industrial anaerobic reactor was developed using calcium acetate as a reference substrate in concentrations of 2000 5000 10000. 15000 and 20000 mg COD/L. A linear growth of methanogenic activity has been obtained in the range of 2000 to 5000 mg COD/L of calcium acetate while for concentrations greater than 10000 mg COD/L of calcium acetate a slight gradual decrease was observed. of methanogenic activity. In the second stage the biological degradation of the algal biomass was evaluated applying thermal and crushing pretreatments. The microalgae digestion alone did not have good yields the COD removal efficiency values ​​with the mentioned pretreatments were below 3%. For this reason it was decided to apply a co-digestion strategy.