Acedo Margarita, Gonzalez Cena Juan R, Kiehlbaugh Kasi M, Ogden Kimberly L
Department of Chemical and Environmental Engineering, University of Arizona.
Department of Biosystems Engineering, University of Arizona.
J Vis Exp. 2020 Aug 14(162). doi: 10.3791/61498.
In the United States, 35% of the total carbon dioxide (CO2) emissions come from the electrical power industry, of which 30% represent natural gas electricity generation. Microalgae can biofix CO2 10 to 15 times faster than plants and convert algal biomass to products of interest, such as biofuels. Thus, this study presents a protocol that demonstrates the potential synergies of microalgae cultivation with a natural gas power plant situated in the southwestern United States in a hot semi-arid climate. State-of-the-art technologies are used to enhance carbon capture and utilization via the green algal species Chlorella sorokiniana, which can be further processed into biofuel. We describe a protocol involving a semi-automated open raceway pond and discuss the results of its performance when it was tested at the Tucson Electric Power plant, in Tucson, Arizona. Flue gas was used as the main carbon source to control pH, and Chlorella sorokiniana was cultivated. An optimized medium was used to grow the algae. The amount of CO2 added to the system as a function of time was closely monitored. Additionally, other physicochemical factors affecting algal growth rate, biomass productivity, and carbon fixation were monitored, including optical density, dissolved oxygen (DO), electroconductivity (EC), and air and pond temperatures. The results indicate that a microalgae yield of up to 0.385 g/L ash-free dry weight is attainable, with a lipid content of 24%. Leveraging synergistic opportunities between CO2 emitters and algal farmers can provide the resources required to increase carbon capture while supporting the sustainable production of algal biofuels and bioproducts.
在美国，二氧化碳（CO₂）排放总量的35%来自电力行业，其中30%是天然气发电产生的。微藻固定CO₂的速度比植物快10到15倍，并能将藻类生物质转化为感兴趣的产品，如生物燃料。因此，本研究提出了一种方案，展示了在美国西南部炎热半干旱气候下微藻养殖与天然气发电厂之间潜在的协同作用。采用先进技术通过绿藻种索氏小球藻增强碳捕获和利用，该绿藻可进一步加工成生物燃料。我们描述了一个涉及半自动开放式跑道池塘的方案，并讨论了其在亚利桑那州图森市图森电力厂测试时的性能结果。使用烟道气作为主要碳源来控制pH值，并培养索氏小球藻。使用优化的培养基来培养藻类。密切监测作为时间函数添加到系统中的CO₂量。此外，还监测了影响藻类生长速率、生物质生产力和碳固定的其他物理化学因素，包括光密度、溶解氧（DO）、电导率（EC）以及空气和池塘温度。结果表明，微藻产量可达0.385克/升无灰干重，脂质含量为24%。利用CO₂排放源与藻类养殖者之间的协同机会，可以提供增加碳捕获所需的资源，同时支持藻类生物燃料和生物产品的可持续生产。
