Production of Microalgae Biomass Using Vinasse as Cultivation Medium.

Microalgae are one of the potential food sources in the future. Many authors have investigated the potential of wastewater as cultivation medium for microalgae, but utilization of sugarcane digested vinasse as cultivation medium for algae has not yet been reported. The purpose of this study was to test the potential of vinasse as an alternative source of nutrients for culturing microalgae.  One pure strain of a green alga (Chlorella vulgaris) and two pure strains of blue green algae (Spirulina platensis and Nostoc commune) were used for this purpose. The three microalgae were grown on six various concentrations of vinasse from 0.01% to 0.03 and from 0.1% to 0.3% for 21 and 35 days. The present investigation showed that digested vinasse contained ammonia (NH3), nitrate (NO3), phosphate (PO4), Calcium (Ca), Magnesium (Mg), Sodium (Na), Potassium (K) and high Electron Conductivity (EC). The highest productivity of biomass by Chlorella vulgaris (368 x 106 mg/L) was observed when using 0.3% vinasse medium,  by Nostoc commune (1400 x 106/L mg/L) when using 0.01% medium and by Spirulina platensis (200 x 106 mg/L) when using 0.02% medium. The period of 35 days was better than 21 days for the growth of all examined species. No algal growth was observed when using higher concentrations of vinasse (from 1% to 6%). The present results show that it is possible to integrate the culturing of microalgae with the sugarcane industry product (vinasse) by means of anaerobic digestion.