Título: OPTIMIZATION OF ULVA PRODUCTION IN RACEWAY PHOTOBIOREACTORS WITH SEAWATER RECIRCULATION: THE CRITICAL FACTORS
Resumen: Ulva is a highly versatile seaweed with applications in human nutrition, animal feed, biofiltration, pharmaceuticals, and as a biomass source for biofuels. While offshore cultivation dominates, inshore systems offer controlled environments that can enhance productivity and mitigate environmental impacts [1]. Raceway photobioreactors, commonly used for microalgae due to their low energy demands and affordability, have been extensively studied and refined over the years [2]. However, their application in seaweed cultivation remains underexplored.
This study explores the optimization of Ulva production in raceway photobioreactors with a surface area of 7 m² and a volume of 1 m³, focusing on key operational parameters to maximize biomass productivity: CO₂ supply, paddlewheel velocity, and harvesting rate. The Ulva was grown under conditions of complete seawater recirculation, ensuring efficient water use and minimizing environmental impact. Among the factors studied, the addition of CO₂ proved to be the most critical factor, resulting in a 77% increase in biomass productivity. An increase of a 50% of paddlewheel velocity further boosted productivity by 33%, although it also led to a 30% reduction in leaf size. Harvesting rate was another crucial factor, with an optimal rate of 0.2 d⁻¹, yielding a 24% productivity increase compared to both higher (0.3 d⁻¹) and lower (0.1 d⁻¹) rates.
Overall, the study achieved a maximum biomass productivity of 29.76 gDW·m⁻²·day⁻¹, demonstrating the strong potential of raceway photobioreactors for large-scale Ulva cultivation. These findings highlight that while multiple factors contribute to optimizing productivity, CO₂ supplementation remains the most influential, offering a promising strategy for improving sustainable seaweed biomass production across various applications.
Congreso: AlgaEurope 2024
