Department of Environment Engineering, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, 10-710 Olsztyn, Poland.
Department of Water Supply and Sewage Systems, Faculty of Civil Engineering and Environmental Sciences, Bialystok University of Technology, 15-351 Bialystok, Poland.
Front Biosci (Elite Ed). 2023 Jan 16;15(1):3. doi: 10.31083/j.fbe1501003.
Carbon dioxide (CO2) is the major contributor to the global emissions of greenhouse gases, which necessitates the search for its fixation and utilization methods. Engaging photosynthesizing microorganisms for its biosequestration is one of the prospective technologies applied to this end. Considering the paucity of literature works on the possibilities of deploying CO2 from biogas combustion to intensify microalgae production, this research aimed to identify the feasibility of using this type of CO2 in culture by evaluating biomass production yield and CO2 biosequestration effectiveness.
The experiment was performed in glass PBR, in which the culture medium occupied the volume of 1.0 dm3, and the gaseous phase occupied 0.3 dm3. The reactors were continuously illuminated by fluorescent lamps. The temperature of flue gases and air fed to reactors, and culture temperature was 20 °C ± 2 °C.
The use of flue gases promoted a more rapid biomass growth, reaching 77.8 ± 3.1 mgVS/dm3⋅d, and produced a higher microalgae concentration, i.e., 780 ± 58 mgVS/dm3. Nevertheless, the flue gas-fed culture turned out to be highly sensitive, which was manifested in a decreased culture medium pH and relatively quickly achieved decay phase of the population. The microalgae effectively assimilated CO2, reducing its concentration from 13 ± 1% to 1 ± 0.5% in the effluent from the photobioreactor.
The flue gases were found not to affect the qualitative composition of the microalgal biomass. However, strict control and monitoring of microalgae biomass production is necessary, as well as rapid responses in flue gas-fed systems. This is an important hint for potential operators of such technological systems on the large scale. Regardless of the possibility of deploying microalgae to fix and utilize CO2, a justified avenue of research is to look for cheap sources of CO2-rich gases.
二氧化碳（CO2）是温室气体排放的主要贡献者，因此需要寻找其固定和利用方法。利用光合作用微生物进行生物固碳是应用于这一目标的有前景的技术之一。考虑到关于利用沼气燃烧产生的 CO2 来加强微藻生产的文献作品稀少，本研究旨在通过评估生物质产量和 CO2 生物固碳效果，确定在培养中使用这种 CO2 的可行性。
实验在玻璃 PBR 中进行，其中培养基体积为 1.0 dm3，气相体积为 0.3 dm3。反应器由荧光灯连续照射。烟道气和供给到反应器的空气的温度以及培养温度为 20°C ± 2°C。
使用烟道气促进了更快的生物质生长，达到 77.8 ± 3.1 mgVS/dm3⋅d，并产生了更高的微藻浓度，即 780 ± 58 mgVS/dm3。然而，烟道气喂养的培养物变得非常敏感，表现为培养基 pH 值下降和种群迅速进入衰退期。微藻有效地同化了 CO2，将其浓度从 13 ± 1%降低到光生物反应器出口处的 1 ± 0.5%。
烟道气未影响微藻生物质的定性组成。然而，需要对微藻生物质生产进行严格的控制和监测，以及对烟道气喂养系统的快速响应。这是大型此类技术系统的潜在操作人员的重要提示。无论是否有可能部署微藻来固定和利用 CO2，寻找廉价的富 CO2 气体来源都是合理的研究途径。
