Chiaramonti D.,University of Florence |
Prussi M.,University of Florence |
Casini D.,University of Florence |
Tredici M.R.,University of Florence |
And 4 more authors.
Applied Energy | Year: 2013
The present work addresses energy consumption in raceway ponds (RWPs). This kind of systems are today the most utilized industrial plant for outdoor algae cultivation. The problem has been addressed combining theoretical correlations and experimental data. Head losses for conventional raceway ponds were evaluated, and the results were compared with data available in literature. Computational fluid dynamics was used to support the theoretical analysis. This study suggested possible improvements to the traditional RWP design: an Innovative Raceway Pond (IRP II) was therefore designed, built and operated in parallel with a reference pilot RWP in a test site. Several modifications to traditional RWP design were implemented in the IRP II: the paddle wheel was substituted by a propeller, the water head was reduced and baffle boards were installed in the curves. To validate the new design, head losses and therefore energy consumption in the different systems were evaluated, during cultivation experiments, with two microalgae strains. The theoretical and experimental study allowed a validated calculation, which showed the importance of concentrated head losses towards distributed ones. The analysis highlighted how these losses weight at different pond scales, suggesting possible improvements of the RWP energy performance - as achieved in the IRP II - through revised design for optimized mixing. © 2012 Elsevier Ltd. Source
Bondioli P.,INNOVHUB Stazioni Sperimentali per lIndustria SSOG Division |
Della Bella L.,INNOVHUB Stazioni Sperimentali per lIndustria SSOG Division |
Rivolta G.,INNOVHUB Stazioni Sperimentali per lIndustria SSOG Division |
Chini Zittelli G.,CNR Institute of Ecosystem Study |
And 7 more authors.
Bioresource Technology | Year: 2012
Nannochloropsis sp. F&M-M24 and Tetraselmis suecica F&M-M33 were cultivated outdoors in Green Wall Panels under nutrient deficiency to stimulate oil synthesis. Under nitrogen deprivation, Nannochloropsis attained average biomass and lipid productivities of 9.9 and 6.5gm -2day -1, respectively. Starved Tetraselmis cultures achieved a biomass productivity of about 7.6gm -2day -1 and a lipid productivity of 1.7gm -2day -1. Lipids represented 39.1% and 68.5% of non-starved and starved Nannochloropsis biomass, respectively. Starvation did not increase lipid content in Tetraselmis biomass. Important differences in lipid classes and in fatty acid composition were observed under the different cultivation conditions for both microalgae. © 2012 Elsevier Ltd. Source