Abstract: Smelting slag has been an important area of solid waste research due to the potential environmental risks associated with long-term stockpiling, coupled with its resource property characteristics. In this study, relevant literature published on China Knowledge Network (CNKI) and Web of Science (WoS) in the past 20 years was analyzed using CiteSpace software, and relevant patents in this field in the past 10 years were searched in combination with Incopat database, so as to visualize the hotspots and cutting-edge trend of smelting slag research. The results showed that the amount of literature and patents have generally shown an increasing trend year by year, with China taking the first place in terms of the number of related literature and patents, Australia ranking second in terms of published literatures and South Korea ranking second in terms of the patent numbers. The centrality of the United States is the highest, reaching 0.79, still dominating the field, indicating that China has a high amount of publications, but its core competitiveness and influence are insufficient. The analysis of patented technology fields showed that the technology focus was highly concentrated on the two major paths of valuable metal recycling and building materials utilization (such as cement, ceramics, refractory materials). The analysis of hotspots showed that the research hotspots of the literature and patents were basically the same, mainly focusing on the recycling and comprehensive utilization of valuable heavy metals and the morphology analysis of heavy metals in the leaching solution, with global characteristics. The difference is that the WoS database literature has began to focus on the combination of numerical simulation and other intelligent technologies with this field. Based on the double validation of patents, literature data and policy-driven, the key directions for future research in the field of smelting slag include: precise dissociation and efficient extraction of valuable metals such as Li, Ti, Ni and Cu; research and development of synergistic in-situ solidification/stabilization technology of multiple heavy metals in historical stockpile slag, and new green, low-carbon and economic stabilization technology for increased smelting slag; materialization and high-value utilization based on pollution and carbon reduction synergy; prediction of smelting slag characteristics and process optimization based on numerical simulation, artificial intelligence and other intelligent technologies, and strengthening the integration of numerical simulation, artificial intelligence and other computer sciences with materials science, biology and other disciplines.

Key words: visual analysis, high-value, heavy metal in-situ solidification and stabilization technology, valuable metal extraction, digital intelligence