Recovery of Iron from High-Iron Hot Rolled Mill Scales by Direct Reduction Technique

Abstract

In this study, the integrated iron and steel plant mill scales prepared to concentrate in different ratios by blending with hematite character ore. CMC was used as binder and coke will be used as reductant. The calcite was added in such a way that the basicity ratio is 0.7. The pelletizing machine was pellet the blends containing the mill scales at different ratios and then drying at a temperature of 150 °C. 28 kg / pellet compressive strength was obtained in the pellets prepared from 100% mill scales. As the amount of ore increased, 45 kg / pellet was reached with a 50% increase in compressive strength. After compression tests, dried pellets were subjected to reduction at 3 different temperatures (1200, 1300 and 1400 C) and their reduction degrees were calculated based on oxygen loss. The highest reduction degree (82%) was obtained at 1400 ° C from the completely prepared with mill scales.

Keywords

• Mill scales
• Direct reduction
• Hematite

Doğrudan İndirgeme Tekniğiyle Yüksek Demirli Sıcak Haddehane Tufalinden Demirin Geri Kazanımı

Abstract

Bu çalışmada, hematit karakterli demir cevheri ile entegre demir çelik fabrikası haddehane tufali farklı oranlarda harmanlanarak hazırlanmıştır. Bağlayıcı olarak CMC ve indirgeyici olarak ise kok kullanılmıştır. Baziklik oranı 0.7 olacak şekilde kalsit ilave edilmiştir. Peletleme makinesi ile farklı oranlarda haddehane tufali içeren karışımlar pelet haline getirilmiş ve ardından 150 ° C’de kurutulmuştur. % 100 haddehane tufalinden hazırlanan peletlerde 28 kg / pelet basma dayanımı elde edilmiştir. Cevher miktarı arttıkça basma dayanımında % 50 artışla 45 kg / pelet’e ulaşılmıştır. Basma testlerinden sonra, kurutulmuş peletler 3 farklı sıcaklıkta (1200, 1300 ve 1400 oC) indirgenmeye tabi tutulmuş ve oksijen kaybına göre indirgenme dereceleri hesaplanmıştır. En yüksek indirgenme derecesine (% 82) 1400 oC 'de tamamen haddehane tufali ile hazırlanan peletlerde ulaşılmıştır.

Keywords

• Haddehane tufali
• Doğrudan indirgenme
• Hematit

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