烧成温度对稳定性镁白云石材料性能的影响

摘要

Stabilized magnesia dolomite materials were prepared using synthesized stabilized magnesia dolo-mite materials (MgO 46.6%,CaO 35.0% by mass),adding sulphite liquor as binder,batching,mixing,sha-ping,drying and firing at 1 450,1 500,1 550 and 1 600 ℃for 3 h,respectively.The effect of firing temperature on properties was investigated.The results show that with the increase of the firing temperature from 1 450℃to 1 600 ℃,liner shrinkage,density,cold crushing strength,and cold modulus of rupture increase.Hot modu-lus of rupture of the specimen fired at 1 550 ℃ is the highest,and the coating adherence of the specimen fired at 1 500 ℃ is the best.At high temperatures,CaO in the cement clinker diffuses into the materials and reacts with C2S forming C3S.The stabilizer calcium phosphate in the materials keeps C2S in the interface lay-er existing inβphase form,avoiding crack and pulverization of the coating due to C2S crystal transformation.%为了制备水泥回转窑用烧成稳定性镁白云石材料，以w（MgO）＝46．6％、w（CaO）＝35．0％的稳定性镁白云石合成料为原料，以纸浆废液为结合剂，经配料、混练、成型、干燥后，分别在1450、1500、1550和1600℃保温3 h，制成烧成稳定性镁白云石材料，研究了烧成温度对烧成稳定性镁白云石材料性能的影响。结果表明：随着烧成温度由1450℃提高至1600℃，烧后试样的线收缩率、致密度、常温耐压强度和常温抗折强度均逐渐增大。但高温抗折强度以1550℃烧后试样的为最大，挂窑皮性能则以1500℃烧后试样的为最好。在高温下，水泥熟料中的CaO扩散进入试样中，与试样中的C2 S反应生成C3 S。制备稳定性镁白云石原料过程中加入的稳定剂磷酸钙有利于界面层中的C2 S以稳定的β相存在，避免了因C2 S晶型转化造成的窑皮层开裂和粉化。