磷石膏中杂质的形态及水溶性磷对水泥物理性能的影响

在对磷石膏中杂质的类型、存在形式及磷石膏的溶解性质检测分析的基础上 ,研究了磷石膏中水溶性磷含量以及磷石膏直接替代天然石膏用作水泥缓凝剂对水泥质量的影响。结果表明 ,磷石膏中的主要杂质为 :以H3PO4、H2 PO-4 或HPO2 -4 形式存在的可溶性P2 O5、与金属共生磷酸盐复合物和共晶形式存在的不溶性P2 O5及石英。磷石膏中的水溶性磷含量 <1%时 ,对水泥物理性能的影响不大 ,磷石膏中的水溶性磷含量 >1%时 ,水泥的凝结时间明显延长 ,但对强度影响不大

IMPURITY CONFIGURATION IN PHOSPHOGYPSUM AND INFLUENCE OF WATER-SOLUBLE PHOSPHOROUS PENTOXIDE ON CEMENT PHYSICAL PROPERTY

This paper analyses the type and configuration of impurity in phosphogypsum,and the soluble characters of phosphogypsum.And then,based on the above,the paper goes on with the content of water soluble phosphorous pentoxide in phosphogypsum and the influence of phosphogypsum on cement quality when it is directly substituted as cement retarder for natural gypsum.The study finds that the impurity in phosphogypsum includes:dissolubility P 2O 5 as formation of H 3PO 4,H 2PO - 4 or HPO 2- 4;phosphate compound intergrowing with metals;infusibility P 2O 5 and quartz as formation of cocrystallization.The influence on cement physical property is not too great when the content of water soluble phosphorous pentoxide is less than 1%;when it is more than 1%,the setting time of cement delays evidently,but its influence on the strength of cement is not much in evidence nevertheless.