AUTHOR=Kennes Christian TITLE=The grand challenge of water, waste, wastewater and emissions engineering and valorization JOURNAL=Frontiers in Environmental Engineering VOLUME=2 YEAR=2023 URL=https://www.frontiersin.org/journals/environmental-engineering/articles/10.3389/fenve.2023.1149950 DOI=10.3389/fenve.2023.1149950 ISSN=2813-5067