Unicellular vs. filamentous microalgae for wastewater treatment and nutrient recovery.

REARTE T.A.; RODRIGUEZ N.; SABATTE F.; IORIO A. F. DE

ALGAL RESEARCH

ELSEVIER B.V.

Año: 2021 vol. 59 p. 1 - 11

2211-9264

Microalgae based-process is a promising platform to enhance nutrient recovery in wastewater treatment systems. The use of filamentous microalgae could improve this technology by reducing harvesting cost and enhancing biomass management. The potential of 12 unicellular and 12 filamentous microalgae strains was evaluated for the treatment and nutrient recovery of a raw wastewater from a slaughterhouse (RWS). Chlorococcum sp. FAUBA-42 (unicellular) and Stigeoclonium sp. FAUBA-10 (filamentous) were selected due to their biomass production using RWS as sole nutrient source. Comprehensive analysis of batch and semicontinuous regime was carried out for both strains. Semicontinuous cultures showed three times higher biomass productivity than batch regime. The highest biomass productivity (0.45 g DW L-1 d-1) and photosynthetic efficiency (1.52 g DW mol photons-1) was reached by the filamentous strain Stigeoclonium FAUBA-10 under 0.4 d-1 dilution rate. Both strains showed nutrient removal above 92 % under 0.2 and 0.4 d-1 dilution rates. Biomass of Stigeoclonium FAUBA-10 can be easily harvested by filtration through mesh screens (< 341 μm) which means a great operational advantage.