利用天然镁橄榄石制备轻质原料的工艺研究及其应用

Preparation and application of light-weight raw materials from natural forsterite

为开发新型碱性隔热耐火原料,以天然镁橄榄石细粉、菱镁矿细粉为原料,无烟煤为造孔剂,按镁橄榄石(2MgO·SiO_(2))的化学组成配比后进行湿磨,再干法成型后于不同温度下煅烧,制备了∅36 mm的圆柱试样。研究了转速、煅烧温度以及无烟煤的外加量对试样性能的影响,并将该轻质原料应用于镁橄榄石质浇注料中。结果表明:当煅烧温度达到1300℃后,原料中的矿物相将全部转变为有益的物相。随着转速加快和煅烧温度提高,试样的体积密度上升,显气孔率下降,强度增加。综合考虑,采用400 r·min^(-1)的研磨速度和1450℃的煅烧温度为最佳方案。无烟煤的加入将使得试样进一步轻量化,可以得到微孔分布均匀的轻质原料。所制得的轻质原料在镁橄榄石质浇注料中取得了良好的使用效果。

In order to develop new type basic insulation refractory raw materials,column specimens(∅36 mm)were prepared using natural forsterite fine powder and magnesite fine powder as raw materials,anthracite coal as the pore forming agent,mixing according to the chemical composition of forsterite(2MgO·SiO_(2),and wet milling,then dry molding and calcining at different temperatures.Effects of the rotation speed,calcination temperature and anthracitic coal extra addition on the properties of the specimens were researched.The developed raw materials were applied on forsterite castables.The results show that:when the calcination temperature reaches 1300℃,all mineral phases convert to beneficial phases.With the increase of the rotation speed and the rising calcination temperature,the bulk density of the specimen increases,the apparent porosity decreases and the strength increases.By comprehensive consideration,400 r/min and 1450℃are taken as the most suitable scheme.The addition of anthracitic coal lightens the specimens,the light-weight raw material with uniformly distributed micropores can be gained,and performs well in forsterite castables.