Insights into the potential impact of algae-mediated wastewater beneficiation for the circular bioeconomy: A global perspective. (1st November 2021)

• Record Type: Journal Article
• Authors: Renuka, Nirmal; Ratha, Sachitra Kumar; Kader, Farzana; Rawat, Ismail; Bux, Faizal
• Is Part Of: Journal of environmental management. Volume 297(2021)
• Publication Date: 2021-11-01
• Subjects: Municipal wastewater -- Algae-based system -- Nutrient removal -- Biomass accumulation -- Biocrude -- Biorefinery; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2021.113257
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Algae-based technologies are one of the emerging solutions to societal issues such as accessibility to clean water and carbon-neutral energy and are a contender for the circular bioeconomy. In this review, recent developments in the use of different algal species for nutrient recovery and biomass production in wastewater, challenges, and future perspectives have been addressed. The ratio and bioavailability of nutrients in wastewater are vital parameters, which significantly impact nutrient recovery efficiency and algal biomass production. However, the optimum nutrient concentration and ratio may vary depending upon the microalgal species as well as cultivation conditions. The use of indigenous algae and algae-based consortia with other microorganisms has been proved promising in improving nutrient recovery efficiency and biomass production in pilot scale operations. However, environmental and cultivation conditions also play a significant role in determining the feasibility of the process. This review further focused on the assessment of the potential benefits of algal biomass production, renewable biofuel generation, and CO2 sequestration using wastewater in different countries on the basis of available data on wastewater generation and estimated nutrient contents. It was estimated that 5–10% replacement of fossil crude requirement with algal biofuels would require ~952–1903 billion m 3 of water, 10–21 billion tons of nitrogen, and 2–4 billion tons of phosphorus fertilizers. In this context, coupling wastewater treatment and algal biomass production seem to be the most sustainable option with potential global benefits of polishing wastewater through nutrients recycling and carbon dioxide sequestration. Graphical abstract: Image 1 Highlights: Available municipal wastewater estimated to contain high N and P reserves globally. Efforts directed in unravelling the role of abiotic-biotic factors in algal systems. Wastewater meet the necessities for 5–10% replacement of crude oil with algal crude. Algal crude production can assist in sequestering 10–200 million tons yr −1 of CO2 . Future efforts needed on techno-economic aspects in different geographical regions.