Impact of Flue Gas Compounds on Microalgae and Mechanisms for Carbon Assimilation and Utilization

Abstract

To shift the world to a more sustainable future, it is necessary to phase out the use of fossil fuels and focus on the development of low-carbon alternatives. However, this transition has been slow, so there is still a large dependence on fossil-derived power, and therefore, carbon dioxide is released continuously. Owing to the potential for assimilating and utilizing carbon dioxide to generate carbon-neutral products, such as biodiesel, the application of microalgae technology to capture CO from flue gases has gained significant attention over the past decade. Microalgae offer a more sustainable source of biomass, which can be converted into energy, over conventional fuel crops because they grow more quickly and do not adversely affect the food supply. This review focuses on the technical feasibility of combined carbon fixation and microalgae cultivation for carbon reuse. A range of different carbon metabolisms and the impact of flue gas compounds on microalgae are appraised. Fixation of flue gas carbon dioxide is dependent on the selected microalgae strain and on flue gas compounds/concentrations. Additionally, current pilot-scale demonstrations of microalgae technology for carbon dioxide capture are assessed and its future prospects are discussed. Practical implementation of this technology at an industrial scale still requires significant research, which necessitates multidisciplinary research and development to demonstrate its viability for carbon dioxide capture from flue gases at the commercial level.

Overview of Carbon Capture Technology: Microalgal Biorefinery Concept and State-of-the-Art

“…Recently, many research studies have come up showing the positive impact of growing microalgae under high concentrations of Ci in the form of pure gaseous CO 2 , real or simulated flue gas, or soluble carbonate (bicarbonate), reporting increased carbon bio-fixation and biomass productivity (Ho et al, 2010;Sydney et al, 2010;Yoo et al, 2010;Tang et al, 2011;Singh et al, 2014;Aslam et al, 2017;Kuo et al, 2017). Detailed information can be found in elaborated reviews by Lam et al (2012); Cheah et al (2015); Thomas et al 2016; Vuppaladadiyam et al (2018). The fate of the supplied carbon can end up in making skeleton for lipids, proteins, sugars and pigments (Sydney et al, 2010).…”

Engineering isoprene synthesis in cyanobacteria

“…Cyanobacteria offer the advantage of being able to utilize both CO 2 and bicarbonate as sources of inorganic carbon. Cost-effective means of CO 2 administration would be coupling cultivation of the cyanobacteria with waste resources such as flue gases from power plants [66], biogas from anaerobic digestion of agricultural waste [67], or biogas from aerobic composting of animal manure [68]. Inorganic carbon is also one of the greatest costs associated with scale-up for Isp production, and the CO 2 concentrations in the atmosphere (400 p.p.m.)…”

“…[65] are too low to support high rates of growth. Cost-effective means of CO 2 administration would be coupling cultivation of the cyanobacteria with waste resources such as flue gases from power plants [66], biogas from anaerobic digestion of agricultural waste [67], or biogas from aerobic composting of animal manure [68]. The process of Isp production could thus work dually, as a means of bioremediation, preventing waste CO 2 from entering the atmosphere, and supporting high rates of cyanobacterial photosynthesis and growth.…”

Bioethanol production from agarophyte red seaweed, Gelidium elegans, using a novel sample preparation method for analysing bioethanol content by gas chromatography

“…Algae-based biofuels have high impact, unlike the use of corn or sugarcane (Searchinger et al 2008;Chia et al 2018). Algae have potential to reduce greenhouse gases by consumption of CO 2 emitted from power plants and natural gas operations, as indicated by life-cycle assessments (Maranduba et al 2015;Vuppaladadiyam et al 2018). An advantage of using seaweed is the low lignin content which improves the enzymatic hydrolysis of cellulose.…”