Harnessing microalgae to mitigate the environmental impact of the cement industry: Emission reduction and bio-cement production

The cement industry has been the cornerstone of economic development since the Industrial Revolution. However, the calcination process used to produce cement raw materials releases various pollutants, such as carbon dioxide, nitrogen oxides, and sulfur oxides, which are key contributors to global warming. Therefore, innovative technologies are urgently needed to minimize the environmental impact of the cement industry. In recent years, microalgae have gained attention because of their advantages in recovering resources and reducing the impacts of industrial pollutants. The use of microalgae to address the environmental challenges associated with cement production remains largely overlooked in current reviews. This review summarizes the recent advances in the utilization of microalgae to address the environmental challenges posed by the cement industry. Microalgae offer two main pathways for environmental mitigation: the (i) production of bio-cement as an eco-friendly alternative for construction and (ii) conversion of cement flue gases into biomass feedstock with high-value downstream applications. We also identify existing challenges and propose an integrative “Microalgae–Bacteria Consortium” system as a sustainable strategy for the significant reduction of the environmental footprint of cement production. This approach has the potential to transform the cement industry into a more sustainable and eco-friendlier sector. Overall, microalgae provide an innovative and sustainable platform to revolutionize the cement industry into a greener sector, supporting the global shift toward a low-carbon, circular economy.