Current status of the technology for treating zinc-containing dust and sludge in steel plants using the rotary hearth furnace process

Zinc-containing dust and sludge from steel and metallurgy can lead to environmental pollution, but they can also be important secondary resources. The rotary hearth furnace (RHF) process can efficiently recycle metallurgical dust and sludge. It has become a crucial method for treating zinc-containing dust and sludge in iron and steel enterprises. This study provides a comprehensive overview of the primary sources and physicochemical characteristics of typical steel dust and sludge, while offering detailed insights into the current development status and process principles behind the RHF technique. The technical characteristics and research status of each process unit for treating zinc-containing dust and sludge in RHF were comprehensively summarized, encompassing pellet preparation, drying, reduction, cooling of metallized pellets, and secondary dust treatment of RHF. Furthermore, the challenges encountered during the development of RHF technology were identified and suggestions for future directions were proposed. This work will provide significant insights and serve as a valuable reference for promoting innovation in the treatment processes of zinc − containing dust and sludge utilizing RHFs.