(1. 東北大學 材料與冶金學院，沈陽 110004 ；
2. 中國鋁業(yè)股份有限公司 鄭州研究院，鄭州 450041)
摘 要: 研究添加鐵酸鈣條件下鋁硅比(A/S)為5.96的鋁土礦的溶出規(guī)律對溶出赤泥進行X射線衍射、掃描電鏡和能譜分析。結(jié)果表明：隨鐵酸鈣添加量增多，溶出赤泥鋁硅比和鈉硅比均下降；隨配礦量減少，溶出溫度升高，溶出時間延長，溶出赤泥鋁硅比降低；在溫度為250 ℃，時間為60 min，使用鐵酸鈣添加劑，得到的赤泥鋁硅比為0.69，鈉硅比(N/S)為0.21；赤泥中硅礦物以鐵取代鋁的水化石榴石為主，F(xiàn)e2O3的飽和系數(shù)為0.73，Al2O3的飽和系數(shù)為0.22，SiO2飽和系數(shù)接近1，硅礦物組成改變是赤泥鋁硅比和鈉硅比降低的原因。
關(guān)鍵字: 鋁土礦；鐵酸鈣；拜耳法；溶出
（1. School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China;
2. Zhengzhou Research Institute, Aluminum Corporation of China Limited, Zhengzhou 450041, China）
Abstract:The digesting rule of diasporic bauxite with A/S of 5.96 was studied by adding calcium ferrite. With increasing addition of calcium ferrite, A/S and N/S in the red mud are reduced. Under the conditions of higher digestion temperature and longer time, A/S in the red mud is reduced with lower bauxite addition. Under the condition of 250 ℃, 60 min and adding calcium ferrite, large scale experiments have been done, which results in that A/S in the red mud is 0.69, N/S is 0.21. The main Si-mineral of red mud is ferrite hydro-garnet through analysis of X-ray diffraction and SEM. The coefficient of SiO2 approaches 1, Al2O3 is 0.22, Fe2O3 is 0.73 in ferrite hydro-garnet. It is because the structure of Si-mineral is changed that A/S and N/S in the red mud is greatly reduced.
Key words: bauxite; calcium ferrite; Bayer process; digestion
