title: An enclosed rotating floating photobioreactor (RFP) powered by flowing water for mass cultivation of photosynthetic microalgae.
abstract: BACKGROUND
  The design of photobioreactor (PBR) for outdoor mass cultivation of microalgae determines the distribution of solar irradiance among cells in the culture, mode of agitation, mass transfer efficacy, and energy consumption, thus determines the productivity of the system and the cost of production. In this study, the concept of a floating photobioreactor with rotation function is proposed.Dunaliella tertiolecta, a model microalga, cultured in the attached vessels was evaluated.
  
  
  RESULTS
  The rotation of the photobioreactor was powered by flowing water, in this case waves generated through a paddle wheel in an outdoor raceway pond for proof of concept. The rotating floating PBR (RFP) could be powered by natural flowing stream, river, and tidal waves, thus there could be no energy cost for agitation of the cultures in maintaining the cells in suspension. This RFP is characterized by its energy-saving and temperature control properties as well as more homogenous light distribution in the culture as compared to conventional culture systems, such as raceway pond. Maximal cell concentration of 8.38 × 106cells mL-1, biomass productivity of 3.10 g m-2day-1, and photosynthetic efficiency of 4.61 % (PAR) were achieved. In addition, satisfactory productivities ofD. tertiolectametabolites including carotenoids, mycosporine-like amino acids and lipids were also obtained.
  
  
  CONCLUSIONS
  The RFP, powered by flowing water, creates an innovative culture technology for economical cultivation of microalgal cells and production of microalgal metabolites.
authors: Singapore Peking University Research Centre for a Sustainable Low-Carbon Future (SPURc), CREATE Tower, 1 Create Way, Singapore, 138602 Republic of Singapore ; Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, Singapore, 117597 Republic of Singapore.
authors: Jim Junhui
authors: JJ
authors: Huang
authors: Algae Enviro-Engineering Pte Ltd, 18 Gul Avenue, Singapore, 629660 Republic of Singapore.
authors: Gagarin
authors: G
authors: Bunjamin
authors: Algae Enviro-Engineering Pte Ltd, 18 Gul Avenue, Singapore, 629660 Republic of Singapore.
authors: Edwin Sianguan
authors: ES
authors: Teo
authors: Algae Enviro-Engineering Pte Ltd, 18 Gul Avenue, Singapore, 629660 Republic of Singapore.
authors: Deric Boonhuat
authors: DB
authors: Ng
authors: Singapore Peking University Research Centre for a Sustainable Low-Carbon Future (SPURc), CREATE Tower, 1 Create Way, Singapore, 138602 Republic of Singapore ; Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, Singapore, 117597 Republic of Singapore.
authors: Yuan Kun
authors: 0000-0002-3884-4706
authors: YK
authors: Lee
keywords: Biofuels; Biomass productivity; Dunaliella tertiolecta; Metabolites; Rotating floating photobioreactor; Sodium bicarbonate