不锈钢冷轧重金属污泥的处理与利用对策

Treatment and utilization of heavy metals sludge by cold-rolled stainless steel

不锈钢冷轧重金属污泥成分复杂、产量大、危害严重,已成为不锈钢企业环保治理的难点,目前国内外尚无妥善安全、经济实用的大宗利用途径。针对不锈钢冷轧酸洗废水的来源和特点,提出了一条污泥源头减量、废水两段处理、污泥分段回收的技术路线,由此得到的前段重金属污泥,利用途径可参考含铁尘泥,用作转炉造渣剂、烧结原料、球团矿、生产直接还原铁或其他高附加值产品;后段含以CaSO4,CaF2为主的钙盐污泥,利用途径可参考氟石膏,用作水泥矿化剂、建材原料或冶金辅料。

With complex composition,large output and harmful impact,heavy metal sludge of cold-rolled stainless steel has been a focus of environmental treatment in stainless steel enterprises.At present,there is no proper,safe,economical and practical utilization method both home and abroad.Aiming at the sources and characteristics of by cold-rolled pickling wastewater,a new process route was proposed with sludge originally reduction,two-stage treatment of wastewater and separate recovery of sludge.After two-stage treatment,the front-part（namely,heavy metal sludge） could be considered as ferric sludge and utilized as the material of converter slag,sinter ore,pellet,direct-reduction iron or other high-value-added products;while the post-part（namely,calcium salt sludge） could be considered as fluorgypsum and reused as cement mineralizer,building materials and metallurgical materials.