Status of research on the resource utilization of stainless steel pickling sludge in China: a review

The pickling sludge produced in the stainless steel pickling process is a hazardous waste and disposal in landfill poses a potential environmental risk. Stainless steel pickling sludge contains metal elements such as Fe, Cr, and Ni and substances such as SiO2 and CaO, which have good value for resource recycling. This paper briefly introduces the generation, nature, and hazards of stainless steel pickling sludge; and clustering analysis of relevant literature keywords in recent years; and detailed analysis and comparison of sludge obtained from different steel mills and resource utilization process. The current situation of pickling sludge resource utilization and the development of relevant policies in China in recent years are summarized, and new thoughts on the direction of its resource utilization are put forward.