摘要
云浮硫铁矿尾矿堆存量巨大,影响周边环境且浪费资源。本文探讨将尾矿用作辅助性胶凝材料的可行性,以期实现尾矿的高消纳量利用,分析了尾矿的矿物与化学组成以及硫的赋存状态及含量,研究了尾矿用作辅助性胶凝材料的性能和含有的石膏、黄铁矿的演变及其对性能的影响。结果表明:云浮硫铁矿尾矿属于高硫型尾矿,尾矿中的硫以黄铁矿(FeS_(2))、磁黄铁矿(Fe_(1-x)S)、石膏三种矿物形态存在;在硬化水泥浆体中,尾矿中的FeS_(2)在180 d龄期时氧化程度仍很低;石膏在28 d龄期时大部分已反应生成钙矾石(AFt),是影响性能的主要因素;掺30%(质量分数)硫铁矿尾矿的水泥胶砂28 d活性指数最高可达74%,但相较于3 d和7 d,28 d活性指数不增长甚至下降,180 d龄期抗压强度出现倒缩;将尾矿同时用作水泥混合材和调凝剂可能是一种更好的利用方式。
Yunfu pyrite tailings have a huge storage capacity,which affects the surrounding environment and wastes resources.In this paper,the feasibility of high absorption utilization of tailings used as auxiliary cementitious materials was discussed,the mineral and chemical composition of tailings and the occurrence state and content of sulfur were analyzed,and the properties of tailings as auxiliary cementitious materials and the evolution of gypsum and pyrite contained in tailings and their influence on the properties were studied.The results show that Yunfu pyrite tailings belong to high sulfur pyrite tailings,and the sulfur in the tailings exists in the form of pyrite(FeS_(2)),pyrrhotite(Fe_(1-x)S)and gypsum.In the hardened cement paste,most of the gypsum in the tailings reacts to form ettringite(AFt)at 28 d,which is the main factor affecting the performance,and the oxidation degree of FeS_(2)is still low at 180 d.The 28 d activity index of cement mortar mixed with 30%(mass fraction)pyrite tailings can reach 74%,but compared with 3 d and 7 d,the 28 d activity index does not increase or even decrease,and the compressive strength at 180 d is inverted.It may be a better way to use tailings as cement mixture and coagulant at the same time.
作者
殷素红
曾绍洪
曹文湘
吴焕勋
YIN Suhong;ZENG Shaohong;CAO Wenxiang;WU Huanxun(School of Materials Science and Engineering,South China University of Technology,Guangzhou 510641,China;Guangdong Guangye Yunyu Mining Co.,Ltd.,Yunfu 527300,China)
出处
《硅酸盐通报》
CAS
北大核心
2022年第8期2800-2809,共10页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金国际(地区)合作与交流项目(51561135012)。
关键词
云浮硫铁矿尾矿
辅助性胶凝材料
硫赋存状态
硫含量
FeS_(2)氧化
AFt膨胀
Yunfu pyrite tailing
auxiliary cementitious material
occurrence state of sulfur
content of sulfur
oxidation of FeS_(2)
expansion of ettringite
