title: Hollow glass microspheres for temperature and irradiance control in photobioreactors.
abstract: The addition of hollow glass microspheres (HGM) to polymers to change thermal insulation and mechanical properties is widely used. In this study HGM were tested as a new construction material for photobioreactors to control irradiance and broth temperature in microalgae cultivation. The heat isolation properties of HGMs of three different densities were tested in a polymer matrix. The transmittance (5-50%) and the thermal conductivity (182.05-190.73 W/mK) of the HGM composite material were analyzed. The results were tested in a model to predict the broth temperature and the growth rate as a function of temperature and irradiance. The addition of 1.3 and 0.6 vol.% of HGM lead to an increase in the growth rate of up to 37% and a reduction in the broth temperature up to 9°C. The mechanical resistance of the composites tested is similar to the polymer matrix.
authors.affiliation: Polytechnic School, Laboratory of Bioenergy and Catalysis - LABEC, Federal University of Bahia, Brazil. Electronic address: azevedodarlan@gmail.com.
authors.forename: Darlan A
authors.initials: DA
authors.lastname: Pereira
authors.affiliation: Institute of Chemistry, Department of Physical-Chemistry, Federal University of Bahia, Brazil. Electronic address: nadia@ufba.br.
authors.forename: Nadia M
authors.initials: NM
authors.lastname: José
authors.affiliation: Polytechnic School, Laboratory of Bioenergy and Catalysis - LABEC, Federal University of Bahia, Brazil. Electronic address: somivil@gmail.com.
authors.forename: Sonia M G
authors.initials: SM
authors.lastname: Villamizar
authors.affiliation: Polytechnic School, Laboratory of Bioenergy and Catalysis - LABEC, Federal University of Bahia, Brazil. Electronic address: eas@ufba.br.
authors.forename: Emerson A
authors.initials: EA
authors.lastname: Sales
authors.affiliation: Polytechnic School, Laboratory of Bioenergy and Catalysis - LABEC, Federal University of Bahia, Brazil. Electronic address: louisa@ufba.br.
authors.forename: Louisa W
authors.initials: LW
authors.lastname: Perelo
mesh_terms: D005898:Glass; D058086:Microalgae / Q000378:metabolism; D008863:Microspheres; D058433:Photobioreactors; D013696:Temperature; D013718:Tensile Strength
keywords: Biomass productivity; Heat transfer; Microalgae; Photoinhibition; Polymer matrix composites