New technology for recycling materials from oily cold rolling mill sludge

• Published in: International journal of minerals, metallurgy and materials metallurgy and materials, 2013-12, Vol.20 (12), p.1141-1147
• Main Authors: Liu, Bo, Zhang, Shen-gen, Tian, Jian-jun, Pan, De-an, Meng, Ling, Liu, Yang
• Format: Article
• Language: English
• Subjects: Acid leaching; Cold rolling mills; Metallurgy; Paints; Pigments; Protective coatings; Sludge; 云母氧化铁; 冷轧厂; 含油污泥; 回收利用; 技术; 有机材料; 氧化铁颜料; 油性
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-013-0847-8

Oily cold rolling mill （CRM） sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of ＂hydrometallurgical treatment ＋ hydrothermal synthesis＂ was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide （MIO） pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints （ISO 10601-2007）. This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.