Recent advances in microalgal carbon capture and utilization (bio-CCU) process vis-à-vis conventional carbon capture and storage (CCS) technologies

Abstract

The rise of the global mean temperature as a consequence of incessant anthropogenic greenhouse gas (GHG) emissions, led by CO₂, is one of the direst challenges faced by humankind today. The need of the hour is to minimize fossil fuel usage and capture the atmospheric CO₂. Broadly, the CO₂ mitigation strategies employ carbon capture and storage (CCS) and biological carbon capture and utilization (bio-CCU) technologies. A critical comparative summary of the prevalent CCS and bio-CCU methods has been presented in this study. Among all the CO₂ capture technologies, the microalgal bio-CCU in a biorefinery model is more environment and economy-friendly. Microalgal biorefinery can potentially serve as a platform not only for bio-CCU but also for producing third-generation biofuels and commercially important value-added products as means of wealth generation from waste CO₂. Alongside reducing the world’s reliance on fossil fuels, this approach also directly or indirectly addresses most of the UN’s sustainable development goals (SDGs). To enhance the microalgal CO₂ capture efficiency and consequent biomass productivity, smart bioprocess design and reactor engineering performed by researchers are summarized to understand the progress in this direction. Recent advances, innovations, and existing challenges in the design and development of microalgal cultivation processes and systems, including CO₂ delivery mechanisms, have been critically discussed and assessed in terms of carbon capture efficiency. The futuristic vision for the fourth-generation microalgal biorefinery-based bio-CCU has also been outlined to make some practical recommendations for its successful implementation or adaptation by the thermal power plants and cement industries.

Graphical Abstract

Keywords:

• Bibliometric analysis
• carbon capture and storage (CCS)
• climate change
• microalgal cultivation
• microalgal carbon capture and utilization (bio-CCU)
• open and closed photobioreactors

Handling Editor:

• Amit Bhatnagar

Acknowledgment

Sayari Mukherjee and Ramkrishna Sen gratefully acknowledge their institute, Indian Institute of Technology Kharagpur, for the uninterrupted internet facilities and all subscribed online e-resources and full-text databases. SM recognizes the free service provided by Biorender, VOSviewer, and MS-Powerpoint used for making the figures and MS-Excel for plotting the graph. SM also acknowledges Indian Institute of Technology Kharagpur for providing financial support during her PhD. Scientific inputs of Prof. Mrinal Kumar Maiti, Department of Bioscience and Biotechnology, IIT Kharagpur, are highly appreciated. The help and support of all lab members is acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

SM also acknowledges Indian Institute of Technology Kharagpur for providing financial support during her PhD.