Institute of Systems Biology and Ecology ASCR, Zámek 136, 37333 Nové Hrady, Czech Republic.
J Ind Microbiol Biotechnol. 2010 Dec;37(12):1319-26. doi: 10.1007/s10295-010-0876-5. Epub 2010 Nov 18.
Carbon dioxide (CO₂) availability strongly affects the productivity of algal photobioreactors, where it is dynamically exchanged between different compartments, phases, and chemical forms. To understand the underlying processes, we constructed a nonequilibrium mathematical model of CO₂ dynamics in a flat-panel algal photobioreactor. The model includes mass transfer to the algal suspension from a stream of bubbles of CO₂-enriched air and from the photobioreactor headspace. Also included are the hydration of dissolved CO₂ to bicarbonate ion (HCO₃⁻) as well as uptake and/or cycling of these two chemical forms by the cells. The model was validated in experiments using a laboratory-scale flat-panel photobioreactor that controls light, temperature, and pH and where the concentration of dissolved CO₂, and partial pressure of CO₂ in the photobioreactor exhaust are measured. First, the model prediction was compared with measured CO₂ dynamics that occurred in response to a stepwise change in the CO₂ partial pressure in the gas sparger. Furthermore, the model was used to predict CO₂ dynamics in photobioreactors with unicellular, nitrogen-fixing cyanobacterium Cyanothece sp. The metabolism changes dramatically during a day, and the distribution of CO₂ is expected to exhibit a pronounced diurnal modulation that significantly deviates from chemical equilibrium.
二氧化碳（CO₂）的供应强烈影响着藻类光生物反应器的生产力，因为 CO₂ 在不同的隔室、相和化学形式之间是动态交换的。为了理解潜在的过程，我们构建了一个平面板式藻类光生物反应器中 CO₂ 动力学的非平衡数学模型。该模型包括从富含 CO₂ 的气泡流和光生物反应器顶部空间向藻类悬浮液的传质。还包括溶解的 CO₂水合为碳酸氢根离子（HCO₃⁻）以及这两种化学形式被细胞吸收和/或循环。该模型在使用控制光、温度和 pH 的实验室规模平面板式光生物反应器的实验中得到了验证，其中测量了溶解 CO₂的浓度和光生物反应器废气中的 CO₂分压。首先，将模型预测与由于气体分布器中 CO₂分压的阶跃变化而发生的测量 CO₂动力学进行了比较。此外，该模型用于预测具有单细胞、固氮蓝藻 Cyanothece sp. 的光生物反应器中的 CO₂动力学。在一天中，代谢会发生剧烈变化，并且 CO₂ 的分布预计会表现出明显的昼夜调制，这与化学平衡有很大的偏差。
