文档介绍：Study on Activationof Natural Anhydriteand its Hydration andHardeningCharacteristics A Thesis Submitted to Chongqing University in Partial Fulfillment of the Requirement for the Degree of Master of Material Science and Engineering by Dong Jun Supervisor: Jiahui Major: Material Scienceand Engineering College of Material Science and Engineeringof Chongqing University , Chongqing, China April2008 重庆大学硕士学位论文中文摘要 I 摘要我国天然硬石膏资源储量居世界首位,达300亿吨。硬石膏溶解度大于二水石膏,水化反应是热力学自发过程,具备潜在的胶凝性。但硬石膏结构致密、溶解缓慢、水化活性很低,所以利用率和利用水平都不高。活性激发是硬石膏资源化成效的关键。本文通过粉磨活化、煅烧活化、激发剂激发及无机活性材改性这四种技术途径对硬石膏进行活性激发,并通过测定硬石膏的水化率、水化温升、液相离子浓度、二水石膏析晶过饱和度、粉体细度、标准稠度、凝结时间和硬化体强度、微结构、线膨胀率等,对不同激发途径下硬石膏的水化硬化特性进行了系统、深入的研究。粉磨使硬石膏颗粒细化,与水接触的比表面积增加,溶解加快,水化潜伏期缩短,水化活性提高,粉磨细度应控制在4000~6000cm 2·g -1为宜;助磨剂可以提高硬石膏的易磨性,改善颗粒形貌,%,K 2SO 4适宜掺量为1%。经150℃煅烧,硬石膏中的CaSO 4·2H 2O分解生成β-CaSO 4·1/2H 2O,使硬石膏结构松弛,易磨性提高,粉磨细度增加,平均粒径变小;β-CaSO 4·1/2H 2O具有很高的水化活性,它能够快速水化生成的CaSO 4·2H 2O,对硬石膏的水化产生晶种诱导效应,使硬石膏在液相中CaSO 4·2H 2O晶体成核与生长速率加快。掺加激发剂是提高硬石膏水化活性的有效途径。硫酸盐激发剂使硬石膏水化进程加快,形成富SO 4 2-液相,二水石膏析晶过饱和度提高,二水石膏晶体成核与生长速率加快,晶体尺寸细化,硬化体强度提高。碱性激发剂的激发效果一般比硫酸盐激发剂差,Na 2C 2O 4是硬石膏的高效碱性激发剂,它与硬石膏反应形成 CaC 2O 4沉淀和可溶硫酸盐,使液相SO 4 2-浓度大幅提高,促进硬石膏的水化溶解。复合激发剂对硬石膏的激发效果有一定的差异,3%煅烧明矾与1% Na 2SO 4复合是硬石膏活性激发的高效复合激发剂。硬石膏中掺入矿渣、水泥熟料等无机活性材,矿渣和水泥熟料与硬石膏的水化相互促进,形成钙矾石与水化硅酸钙等水硬性矿物,使硬石膏水化潜伏期缩短、水化进程加快、强度增加、线膨胀率减小、耐水性提高。本研究为合理利用硬石膏资源、发展建筑节能墙体材料提供了技术基础,对硬石膏的建材资源化以及新型胶凝材料的开发应用具有一定的指导意义。关键词:天然硬石膏,粉磨,煅烧,激发剂,无机活性材重庆大学硕士学位论文英文摘要 II ABSTRACT Chinese resource storage capacity of natural anhydrite is number one in world, and it reach 300 hundred million of anhydrite is greater than gypsum, and its hydration reaction is thermodynamics autogenitc process, and have potential jilling its structure is densify, and solution is slow, and hydration activity is very low, so its utilization ratio and utilization level are very low. Activity excitation is key of utilization of anhydrite. In this paper, four technic paths of milling, calcinatin, excit