RESUMEN

An effective CO2 supply system of a spraying absorption tower combined with an outdoor ORWP (open raceway pond) for microalgae photoautotrophic cultivation is developed in this paper. The microalgae yield, productivity and CO2 fixation efficiency were investigated, and compared with those of bubbling method. The maximum yield and productivity of biomass were achieved 0.927gL(-1) and 0.114gL(-1)day(-1), respectively. The fixation efficiency of CO2 by microalgae with the spraying tower reached 50%, whereas only 11.17% for bubbling method. Pure CO2 can be used in the spraying absorption tower, and the flow rate was only about one third of the bubbling cultivation. It shows that this new method of quantifiable control CO2 supply can meet the requirements of the growth of microalgae cultivation on large-scale.

Asunto(s)

Dióxido de Carbono/química , Microalgas/crecimiento & desarrollo , Biomasa , Dióxido de Carbono/metabolismo , Conservación de los Recursos Energéticos , Fotobiorreactores , Fotosíntesis

RESUMEN

The anomalous solubility maximum of CO2 in polymer thin films in the vicinity of the critical temperature and pressure has not yet been clearly understood when the quartz crystal microbalance (QCM) technique has been used to determine the micromass change. In this study, the adsorption of CO2 on the surface of bare polished and unpolished crystals at different pressures and temperatures was investigated using the QCM technique to illustrate why a plot of the true frequency shift as a function of temperature and pressure can intuitively exhibit the adsorption behavior of CO2 on bare crystals. The sorption of CO2 into a PMMA film at different temperatures, pressures, and PMMA film thicknesses was also investigated. An accurate solubility for CO2 in the PMMA film could be obtained by an improved data correction method from the linear relation between the true frequency shift and the polymer film mass, and the anomalous solubility maximum could be corrected by this method. The mechanism of nonabsorbed CO2 transitorily staying in the interspace between the PMMA film and the crystal surface can be explained by the morphology change of the PMMA film. The assumption of "passerby CO2" was satisfactorily confirmed to explain the anomalous sorption behavior of CO2 into PMMA films in the vicinity of the CO2 critical temperature and pressure, and this assumption could be valid for other CO2-polymer thin film systems.