Bibliometric analysis on mercury emissions from coal-fired power plants: a systematic review and future prospect

Abstract

Coal-red power plants (CFPPs) are one of the most signi cant sources of mercury emissions certi ed by the Minamata Convention, which has attracted much attention in recent years. In this study, we used the Web of Science (WOS) and CiteSpace to analyze the knowledge structure of this eld from 2000 to 2022 and then reviewed it systematically. The eld of mercury emissions from coal-red power plants has developed steadily. The research hotspots can be divided into three categories: 1) emission characterization research focused on speciation changes and emission calculations; 2) emission control research focused on control technologies; 3) environmental impact research focused on environmental pollution and health risk. In conclusion, using an oxygen-rich atmosphere for combustion and installing high-e ciency air pollution control devices (APCDs) helped to reduce the formation of Hg 0 . The average mercury removal rates of APCDs and modi ed adsorbents after ultra-low emission retro t were distributed in the range of 82-93% and 41-100%, respectively. The risk level of mercury in combustion by-products was highest in desulfurization sludge (RAC>10%) and followed by y ash(10<RAC<30%) and desulfurization gypsum(1<RAC<10%). Additionally, we found that the implementation of pollution and carbon reduction policies in China had reduced mercury emissions from CFPPs by 45% from 2007 to 2015, increased the e ciency of mercury removal from APCDs to a maximum of 96%, and reduced global transport and health risk of atmospheric mercury. The results conjunctively achieved by CiteSpace and the literature review will enhance understanding of CFPPs mercury emissions research and provide new perspectives for future research.visualizing and describing trends in research data by constructing collaborative information and cooccurrence networks in the literature (Chen, 2006). It has been widely used in many research elds such as information science, medicine, and environmental science (Chen et al., 2012;Hou et al., 2018;Zhu and Hua, 2017). Chao et al. reviewed heavy metal pollution in CFPPs using bibliometric studies and the results showed that the recent hotspots were harmful trace elements and speciation analysis (Chao et al., 2021). Although atmospheric mercury is the most frequent keyword in this knowledge eld, there is still a gap in the metrological analysis of the subcategory of mercury emissions from CFPPs.In this study, we utilized the bibliometric software CiteSpace and the date from the Web of Science (WOS) core collection to analyze the knowledge structure of mercury emissions from CFPPs from 2000 to 2022. The aim was to identify the research power network in the knowledge area and to identify the research hotspots and evolutionary pathways of mercury emissions from CFPPs. Based on this analysis, we conducted a literature review to explore the hotspots and suggest future research trends and directions in the context of current policies for pollution and carbon reduction. We believed that our ndings would provide references and a ...