磷石膏改善氯氧镁水泥耐水性的可行性研究  

Study on the Feasibility of Improving Water Resistance of Magnesium Oxychloride Cement by Phosphogypsum

作　　者：李天鹏 严云[1] 胡志华[1] 谢晓丽[1] Li Tianpeng;Yan Yun;Hu Zhihua;Xie Xiaoli(School of Material Science and Engineering,Southwest University of Science and Technology,Mianyang,Sichuan 621010)

机构地区：[1]西南科技大学材料科学与工程学院,四川绵阳621010

出　　处：《非金属矿》2020年第6期13-16,共4页Non-Metallic Mines

基　　金：国家自然科学基金(51808465);四川省科技厅基础研究项目(2020YJ0422)。

摘　　要：探索磷石膏中含有的可溶性磷杂质改善氯氧镁水泥(MOC)耐水性的可行性。研究可溶性磷杂质含量及外加磷酸对MOC的抗压强度、耐水性的影响规律,并对硬化体的微观结构进行X射线衍射(XRD)、扫描电镜(SEM)等分析。结果表明,磷石膏中可溶磷含量为0.136%,磷石膏可以改善MOC的耐水性,体系中可溶磷含量是影响耐水性的最重要因素。120%掺量磷石膏可使MOC的14 d和28 d软化系数分别达到0.81和0.64;80%磷石膏和1%磷酸复合使用时,MOC的28 d抗压强度为76.1 MPa,28 d软化系数达到0.92。可溶磷和磷酸在MOC中发生化学反应,通过阻止5相的溶解来提升耐水性。掺入磷石膏可以降低MOC的成本,为利用磷石膏提供了新途径。The feasibility of improving water resistance of magnesium oxychloride cement(MOC)by soluble phosphorus impurity in phosphogypsum was studied.Effects of soluble phosphorus and phosphoric acid on water resistance and compressive strength of MOC were studied,and the microstructure of harded paste were investigated using XRD,SEM analysis.The results show that the soluble phosphorus content in phosphogypsum is 0.136%,phosphogypsum can improve the water resistance of MOC,the soluble phosphorus content in the system is the most important factor affecting water resistance.Adding 120%phosphogypsum,the 14 d and 28 d of MOC softening coefficients were 0.81 and 0.64 respectively;the 28 d compressive strength of MOC is 76.1 MPa,and the softening coefficient of 28 d can reach 0.92 when 80%phosphogypsum and 1%phosphoric acid were used together.Soluble phosphorus and phosphoric acid can react in MOC to improve water resistance by preventing the dissolution of 5 phases.Phosphogypsum will reduce the cost of MOC,Which provide a new way to use phosphogypsum.

关 键 词：氯氧镁水泥 磷石膏 可溶磷 软化系数 

分 类 号：TQ172.7[化学工程—水泥工业]