Global Research Progress on Municipal Waste and Future Prospect Based on the Cross-national Comparisons

Due to the acceleration of urbanization, the municipal waste (MW) problem has transformed into a global challenge for urban sustainability. To elucidate historical trends, current focal points, and future directions in MW research, we conducted a bibliometric analysis and employed knowledge graph visualization to scrutinize a total of 34 212 articles, which were published between 1991 and 2021 in the Web of Science (WoS) core database. The results indicated that current major research themes encompass waste classification and recycling, waste management and public behavior, waste disposal methods and technologies, as well as environmental impact and evaluation. There has been a shift in the research focus from the environmental impacts of waste incineration to sustainable management related issues. A comparison of research from six typical countries revealed the differences in research priorities and techniques advantages. Scholars from the USA and Britain initiated MW research earlier than other countries and investigated management issues in depth, such as public behavior and willingness to pay. Meanwhile, Japanese, German, and Swedish scholars conducted extensive studies on advanced waste treatment technologies, such as disposal and recycling, risk assessment, and waste-to-energy techniques. Chinese scholars placed particular emphasis on end-of-pipe treatments and their associated environmental impacts. Hotspots and potential future frontiers were identified by burst detection analysis. Keywords with high value of burst index (BI) worldwide are food waste and circular economy. Chinese scholars have put great efforts on waste environmental impact and its recycling technologies, while we' re expecting to further investigating vulnerable population. Furthermore, this study contributes to bridging the regional gap of scientific research among different countries and fostering international collaboration.