Every drop of safe and clean drinking water all over the world is getting more valuable than before. In the meantime, dirty water is a potential threat to public health. Agriculture, which accounts for most of the water withdrawals worldwide, plays a significant role in water pollution. To prevent this and increase the available clean water, wastewater technologies have a crucial function.

To this note, researchers Professor Shu-Yuan Pan and Yu-I Lin at the National Taiwan University and Nidhi Mehta at the University of Washington described and analyzed the performance of various circular technologies for the conversion of agricultural wastewater to value-added resources and published the review article in the peer-reviewed journal, Environments on last March. This work was supported by Ministry of Science and Technology, Taiwan (ROC).

Dr. Pan and colleagues began the review by summarising the characteristics of potential value-added agricultural wastewater products. “Organic (humic) substances and nutrients are the main compositions of agricultural wastewater and need to be recovered since they enhance the growth of a plant and its roots,” said led author Dr. Pan. Nutrients, such as nitrogen and phosphorus, are top-level examples that are necessary to be recovered or removed from the wastewater. “Just knowing the fact that 5–7% of global energy production is consumed for the mining of phosphorus-containing rocks, we can understand how important it is” added, Dr. Pan. For this purpose, the team summarized the methods of the recovery of humic substances and nutrients from agricultural wastewater. Although adsorption techniques are the most efficient one over chemical and physical processes, using a single method retrieving organic substances can be difficult due to the large variety of their properties.

Later, scientists discussed advancements in implementing circular bioeconomy concepts for the conversion of agricultural wastewater to value-added products. According to the team, recovering resources from agriculture, wastewater reduces the environmental impacts and offers an opportunity to achieve a sustainable/resource-efficient world. Dr. Pan said, “Nowadays, the shortages of water, energy and resources are worldwide crises due to pollution, extreme weather and population increase.” To this end, retrieving these resources can contribute to addressing these existing and potential issues of humankind. Dr. Pan and colleagues highlighted the importance of optimizing the environmental benefits of suitable circular technologies for agricultural wastewater in the study.

Finally, the team demonstrated the prospects and the perspectives for agricultural wastewater circular technologies regarding a concept of a circular bioeconomic system. The energy efficiency design for energy-based technology should be a priority for future research. “Along the way, the Green Chemistry Principles should be incorporated with the design of energy-efficient circular technologies” said, Dr. Pan. Although circular bioeconomy systems offer considerable environmental benefits, the ecological consequences of the recovery process itself also need to be taken into account and analyzed.

Due to the growing global population, improved living standards, variation in consumption patterns, and agricultural irrigation standards, scarcity and demand for clean water will continue to rise. The findings from this critical study will guide future studies on circular bioeconomy technologies.

Journal Reference:

Mehta, N.; Shah, K.J; Lin, Y.-I; Sun, Y.; Pan, S.-Y. Advances in Circular Bioeconomy Technologies: From Agricultural Wastewater to Value-Added Resources. Environments 2021, 8, 20. https://doi.org/10.3390/environments8030020

About the Author

Assistant Professor

Shu-Yuan Pan, Ph.D.

Dr Shu-Yuan PAN (Taiwan) - Green TalentsShu-Yuan Pan is an assistant professor at the Department of Bioenvironmental Systems Engineering, National Taiwan University (NTU). His research work focuses on developing advanced energy-efficient technologies for recovering value-added resources from wastes. He has extensive experience in waste-to-energy and -resource technologies towards responsible production and consumption, including large-scale demonstration of carbon utilization technologies in China Steel Corp. since 2011. Shu-Yuan leads Green Technology Laboratory at NTU, aiming to dedicate the GREAT (Green Research for Environmental and Agricultural Technologies) to achieve a circular bioeconomy system. Due to his outstanding performance, he received several international awards, such as “Green Talent Follow” by Germany; and was included in the list of “World’s Top 2% Scientists 2020” in the field of energy and environmental science. He has published over 80 SCI papers with total citations of >3300 and the h-index of 29. He held eight patents in the field of circular technologies. He was a postdoctoral research fellow at Lawrence Berkeley National Laboratory, the USA, in 2018−2019; a visiting scholar at Argonne National Laboratory, the USA in 2015−2016; a visiting scholar at RWTH Aachen University, Germany in 2014. He held a Ph.D. and a master’s in environmental engineering from NTU and a bachelor’s in geography from NTU.

webpage link: https://webpageprodvm.ntu.edu.tw/GTLab/