Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211, USA.
Water Environ Res. 2018 Jul 1;90(7):650-658. doi: 10.2175/106143017X15131012153121.
Algae generally prefer CO2 through passive gas diffusion to HCO-3 or CO2-3, as uptake of carbonate species relies on active transport. In this study, the effects of CO2 bubbling on algal growth, nutrient uptake, lipid accumulation, and membrane fouling control were investigated in an algal membrane bioreactor (A-MBR). Bubbling with 10% CO2 in the A-MBR system increased algal specific oxygen production rate by 43 ± 5% and algal productivity by 39 ± 1%, even though there was abundant dissolved inorganic carbon available in the secondary wastewater effluent (about 3.6 mM). Meanwhile, nitrogen removal capacity increased from originally 2.6 ± 0.4 g/m3•d to 3.6 ± 0.4 g/m3•d through continuous CO2 bubbling. Furthermore, membrane fouling was significantly reduced in the A-MBR system with CO2 addition, likely because of reduced mineral precipitation on the membrane at lower pHs.
藻类通常更倾向于通过被动气体扩散来吸收 CO2，而不是 HCO-3 或 CO2-3，因为碳酸盐的吸收依赖于主动运输。在这项研究中，在藻类膜生物反应器（A-MBR）中考察了 CO2 鼓泡对藻类生长、营养物质吸收、脂质积累和膜污染控制的影响。在 A-MBR 系统中鼓入 10%的 CO2 可将藻类比耗氧速率提高 43 ± 5%，藻类生产力提高 39 ± 1%，尽管二级废水出水（约 3.6 mM）中含有丰富的溶解无机碳。同时，通过连续 CO2 鼓泡，氮去除能力从原来的 2.6 ± 0.4 g/m3•d 增加到 3.6 ± 0.4 g/m3•d。此外，在添加 CO2 的 A-MBR 系统中，膜污染显著减少，这可能是由于较低 pH 下膜上矿物质沉淀减少所致。
