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 2,000, 5,000, 10,000. , 15,000 and 20,000 mg COD/L. A linear growth of methanogenic activity has been obtained in the range of 2,000 to 5,000 mg COD/L of calcium acetate, while for concentrations greater than 10,000 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.