Potential for Biomass Production of Azolla Pinnata Using Olive Mill Wastewaters as New Bioprocess to Promote Sustainability and Produce Animal Feed, in Line with the SDGs

In this work, the response of the Azolla pinnata to growth using the available nutrients in olive oil washing wastewater (OOWW) has been studied. In this sense, the operation conditions were: temperature, pressure and illumination intensity environment. The experimental results showed that the concentration of 75% (v/v) of OOWW, registered high values for the maximum specific growth rate, µm (0.088 d- 1) and volumetric biomass productivity, Pb (3.7 10-3 g dm-3 d-1). At the same time, higher values for productivities in total chlorophyll (8.2%), carotenoids (0.61 %), crude protein (27.0 %), and total lipids (19.3%), have been obtained. The determination of fatty acid profiles indicated a lipid fraction suitable for biofuel production. Regarding to treated OOWW, high removal percentages for chemical oxygen demand (91.0%), total phenolic compounds (61.1%), total nitrogen (71.7%) and total phosphorus (100.0%) were achieved. The final quality parameters of treated OOWW indicated that it is able to be used in irrigation of olive grove or in the extraction process itself.