ABSTRACT
This study evaluated the feasibility of using vinasse as a nutrient source for microalgae cultivation. The Scenedesmus sp was grown in a medium supplemented with vinasse and process variables were optimized using a factorial design and a Central Composite Design (CCD). The factorial design results showed that it was possible to cultivate microalgae at concentrations of up to 40% of vinasse in the culture medium. The CCD results showed that the light intensity and vinasse concentration influenced the amount of biomass produced.
ABSTRACT
This study aimed at evaluating the best conditions for lipid accumulation in the marine microalga Nannochloropsis oculata in an airlift photobioreactor. Experiments were carried out following a central composite design with the following variables: temperature (19 to 29°C), sodium nitrate concentration (NaNO3) in the culture medium (f/2) (25 to 125 mg.L-1) and incident light intensity (49 to 140 µE.m-2s-1). The maximum lipid production was 132.4 mg.L-1 under the following conditions: 27°C, NaNO3 concentration 105 mg.L-1 and 122 µE.m-2.s-1, which was 30% of dry weight of the biomass.
ABSTRACT
The aim of this work was to look for an efficient and environmentally safe solution for the leather tanning industry through a problem of non-linear programming. The results were promising and showed a significant potential of wastewater reduction. Reuse of internal streams reduced around 70 percent wastewater. The solutions obtained could reduce significantly the amount of chemicals and consequently the amount of waste to be treated.