Research progress on recycling methods of chromium-containing sludge 含铬污泥资源化方法研究进展

The electroplating, dyeing and tanning industries produce a large amount of solid waste in the production process, as the solid waste contains the heavy metal chromium and is easily transformed into the highly toxic hexavalent chromium, resulting in the development of the entire industry being constrained. This paper provides a brief description of the causes and composition of chromium-containing sludge in various industries and introduces the conventional methods of treating chromium-containing sludge, which are no longer in line with the concept of sustainable development due to their impact on the environment. The composition of chromium-containing sludge is complex and has potential utilization value. In both conventional and resource-based treatment methods, the focus is on how to avoid the conversion of the heavy metal chromium in chromium-containing sludge into the highly toxic hexavalent chromium. An industry inquiry into the mechanism of conversion of trivalent chromium to hexavalent chromium is presented and suitable treatment methods are found to immobilise and encapsulate the heavy metal chromium. It not only inhibits the conversion of trivalent chromium to hexavalent chromium, but also allows for the resourceful use of solid waste at the same time.