title: Evaluation of carbon dioxide mass transfer in raceway reactors for microalgae culture using flue gases.
abstract: Mass transfer of CO2 from flue gas was quantified in a 100m(2) raceway. The carbonation sump was operated with and without a baffle at different liquid/gas ratios, with the latter having the greatest influence on CO2 recovery from the flue gas. A rate of mass transfer sufficient to meet the demands of an actively growing algal culture was best achieved by maintaining pH at ∼8. Full optimisation of the process required both pH control and selection of the best liquid/gas flow ratio. A carbon transfer rate of 10gCmin(-1) supporting an algal productivity of 17gm(-2)day(-1) was achieved with only 4% direct loss of CO2 in the sump. 66% of the carbon was incorporated into biomass, while 6% was lost by outgassing and the remainder as dissolved carbon in the liquid phase. Use of a sump baffle required additional power without significantly improving carbon mass transfer.
authors.affiliation: Aqualia Gestión Integral del Agua S.A., C/Ulises, 18, 28043 Madrid, Spain.
authors.forename: I
authors.initials: I
authors.lastname: de Godos
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, Southampton, UK.
authors.forename: J L
authors.initials: JL
authors.lastname: Mendoza
authors.affiliation: Department of Chemical Engineering, University of Almería, 04120 Almería, Spain. Electronic address: facien@ual.es.
authors.forename: F G
authors.initials: FG
authors.lastname: Acién
authors.affiliation: Department of Chemical Engineering, University of Almería, 04120 Almería, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Molina
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, Southampton, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Banks
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, Southampton, UK.
authors.forename: S
authors.initials: S
authors.lastname: Heaven
authors.affiliation: Aqualia Gestión Integral del Agua S.A., C/Ulises, 18, 28043 Madrid, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Rogalla
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D002244:Carbon / Q000494:pharmacology; D002245:Carbon Dioxide / Q000302:isolation & purification / Q000494:pharmacology*; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D058086:Microalgae / Q000187:drug effects / Q000254:growth & development*; D012212:Rheology / Q000187:drug effects; D013997:Time Factors
chemical_list: D002245:Carbon Dioxide; D002244:Carbon
keywords: CO(2) removal; Carbonation; Mass transfer; Microalgae culture; Raceway reactors