不同预处理工艺对磷石膏性能的影响

为研究不同预处理工艺对磷石膏性能的影响,通过X射线衍射、X射线荧光光谱、扫描电子显微镜、热重分析等手段表征磷石膏化学组分、微观形貌、晶型等特征,然后分别用普通煅烧法、微波煅烧法、水洗法、球磨法工艺对原状磷石膏进行力学性能、工作性能、凝结时间及需水量等指标的对比研究。结果表明：普通煅烧法、水洗法对可溶性五氧化二磷、氟类和有机质等杂质去除效果明显;微波煅烧法时间短,只需20 min左右;球磨法能细化颗粒,处理时间在20 min左右最佳。通过预处理制备的磷石膏物理化学特性都得到很大改善,抗压、抗折强度均优于GB/T 9776—2008《建筑石膏》指标,具有巨大的应用前景。

Effect of different pretreatment processes on properties of phosphogypsum

In order to study the effect of different pretreatment processes on the properties of phosphogypsum,the chemical composition,micro morphology and crystal form of phosphogypsum were characterized by X-ray diffraction,X-ray fluorescence,scanning electron microscope and thermogravimetric analysis.The index of mechanical properties,working properties,setting time and water demand of undisturbed phosphogypsum were compared by calcination method,microwave calcination method,water washing method and ball milling method.The results showed that the calcination method and water washing method had obvious removal effect on soluble P₂O₅,fluorine and organic matter.The time of microwave calcination was short,only about 20 min.The ball milling method could refine particles,and the best treatment time was about 20 min.The physical and chemical properties of phosphogypsum prepared by pretreatment had been greatly improved,and the compressive strength and flexural strength were better than the 《calcined gypsum》（GB/T 9776—2008）standard,which had a great application prospect.