(中南大學(xué) 資源加工與生物工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 不銹鋼行業(yè)每年會(huì)產(chǎn)生大量的不銹鋼塵泥，其中含有Fe、Cr、Ni等有價(jià)元素。目前不銹鋼塵泥常用的處理方法如簡(jiǎn)單填埋和堆存，存在處理不完全、易產(chǎn)生二次污染、處理成本高等問題。本文提出了一種以球團(tuán)預(yù)還原-熔煉來綜合利用不銹鋼酸洗污泥、除塵灰、氧化鐵皮的新工藝。結(jié)果表明：不銹鋼塵泥球團(tuán)在預(yù)還原溫度1250 ℃，預(yù)還原時(shí)間80 min，C、Fe質(zhì)量比為1.5，內(nèi)配炭量2%的條件下還原時(shí)，所得預(yù)還原球團(tuán)抗壓強(qiáng)度為685 N，金屬化率為82.84%。該預(yù)還原球團(tuán)在配焦量為8%和溫度1625 ℃下熔煉20 min，得到鉻鐵合金中Fe、Cr、Ni含量分別為66.90%、20.28%和0.96%，回收率分別為97.62%、97.91%、96.45%。該工藝可以高效地回收不銹鋼塵泥中的有價(jià)金屬，獲得的鉻鐵合金可作為200系、300系不銹鋼冶煉的爐料。
關(guān)鍵字: 不銹鋼塵泥；球團(tuán)；預(yù)還原；熔煉；鉻鐵合金
（School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China）
Abstract:Stainless steel, a corrosion-resistant and high-hardness material, has been widely used in chemical, medical, industrial, and other fields. However, large amounts of stainless steel dust and sludge were produced annually from the stainless steel industry, including stainless steel pickling sludge, dedusting ash, and iron oxide scale, etc. The stainless steel dust and sludge were crucial secondary resource with a high utilization value for valuable metal elements (i.e., Fe, Cr, and Ni). At present, the simple landfill and stacking treatment methods for handling stainless steel dust and sludge generally has limitations in incomplete treatment, secondary pollution, and high processing cost. Therefore, for improving the disadvantages of traditional methods, this study proposed a new process with pre-reducing and smelting to comprehensively utilize stainless steel pickling sludge, dedusting ash, and iron oxide scale. The results show that the compressive strength of pre-reduced pellets is 685N each pellet, and the metallization rate is 82.84%, under the conditions of pre-reduction temperature of 1250 ℃, pre-reduction time of 80 min, total carbon-iron mass ratio of 1.5, carbon-burdened amount of 2%. Then, the pre-reduced pellets are smelted for 20 min at coke amount of 8% and temperature of 1625 ℃. Fe, Cr, and Ni contents in the ferrochromium alloy are 66.90%, 20.28%, and 0.96%, respectively, and the corresponding recovery rates are 97.62%, 97.91%, and 96.45%, respectively. Thus, it indicates that the pellet pre-reduction-smelting process can efficiently recover valuable metals from stainless steel dust and sludge. Besides, the obtained ferrochrome alloy material can be applied in 200 series and 300 series stainless steel smelting charges. In summary, the process shows great potential to realize the resource utilization of stainless steel dust and sludge and makes feasible reference to deal with the solid waste in the stainless steel industry.
Key words: stainless steel dust and sludge; pellet; pre-reduction; smelting; ferrochromium alloy
