Microalgae cultivation for dairy wastewater treatment: Insight from recent research and bibliometric analysis

With the continuous increase in dairy production, large amounts of wastewater containing organic matter and nutrients are generated. Finding effective methods for treating dairy wastewater (DWW) is vital for protecting the environment and water resources. In this context, microalgae cultivation emerges as a promising technology for treating DWW and producing biofuel at the same time. This bibliometric study aims to analyze the published research on the use of microalgae in treating DWW. The primary research trends and specific challenges and opportunities in this field will be explored. A bibliometric analysis of 126 articles and review articles in this field from the Scopus database was conducted. The analysis also shows that slightly over 69 % of the publications were published in the last five years, implying growing concern about the cultivation of microalgae to treat DWW. As per the findings of the conducted research, the three most important journals in this field include Bioresource Technology, Environmental Science and Pollution Research, and Algal Research. Significant contributors to the research were India, China, the US, Iran, Italy, South Korea, Taiwan, and Greece with Tunghai University and National Cheng Kung University. The primary research direction in this field is properly indicated by the frequently used keywords related to microalgae cultivation in DWW that were identified, including "Microalgae," "Dairy Wastewater," "Wastewater Treatment," "Nutrient Removal," "Biomass," and "Biodiesel." Chlorella vulgaris, Cyanobacteria, and Scenedesmus obliquus are common species of microalgae used to treat DWW. • 126 articles on dairy wastewater treatment using microalgae were extracted from Scopus. • India, China, and the US lead in dairy wastewater publication numbers. • Anaerobic digestion and photobioreactors are the most used treatment methods. • Journal of Bioresource Technology is the most prolific journal in DWW treatment. • Chlorella vulgaris and Cyanobacteria are common species of microalgae used to treat DWW.