白云鄂博铁精矿造块过程中含钾脉石与萤石的相互作用

Interactions of potassium gangue with fluorite in the process of Bayan Obo iron ore agglomeration gangue

通过对钾长石体系、钾长石-萤石体系及钾长石-萤石-CaO体系在内的含钾长石体系的高温焙烧过程的实验研究,确定了钾长石与萤石不同温度下相互作用的产物.研究结果表明,钾长石在1090℃开始发生分解反应,生成白榴石（KAlSi2O6）和SiO2.钾长石中加入CaF2,900℃就已经发生钾长石的分解反应,1060℃开始有硅铝酸盐的生成;钾长石中加入CaF2和CaO,体系中有硅铝酸盐生成,并在1050℃开始生成枪晶石（3CaO·2SiO2·CaF2）,1270℃有镁黄长石（2CaO·MgO·2SiO2）和铝黄长石（2CaO·Al2O3·SiO2）;焙烧过程伴随有KF生成.

The high temperature roasting process of the potash feldspar system, the potash feldspar-fluorite system and the potash feld- spar-fluorite-CaO system were studied, and the outcome of the interaction between potash feldspar and fluorite was evaluated. The results shows that the decomposition reaction of potash feldspar began at the temperature of 1 090℃. Different chemical reactions oc- curred in the heating process, with the addition of CaF2 and CaO. The decomposition reaction of potash feldspar already happened at the temperature of 900℃ and aluminosilicate was generated at the temperature of 1 060℃, with the addition of CaF2. With the addition of CaF2 and CaO, not only aluminosilicate（ at the temperature of 1 050 ℃ ） but also cuspidine and merwinite （at the temperature of 1 270℃）were obtained , with the gas of KF generated in the firing process.