基于磷石膏的多骨料充填体强度演化规律研究  

Research on the Strength Evolution Rule of Multi-aggregate Filling Body Based on Phosphogypsum

作　　者：罗芳[1] 贺严[2] 焦文宇 朱必勇 康虔 LUO Fang;HE Yan;JIAO Wenyu;ZHU Biyong;KANG Qian(School of Civil Engineering,Zhengzhou Inst让ute of Finance and Economics,Zhengzhou,Henan 450000,China;School of Resources and Safety Engineering,Central South University,Changsha,Hunan 410083,China;Changsha Institute of Mining Research Co.,Ltd,Changsha,Hunan 410012,China;Key Laboratory of Safety and Health in Metal Mines,Maanshan,Anhui 243000,China)

机构地区：[1]郑州财经学院土木工程学院,河南郑州450000 [2]中南大学资源与安全工程学院,湖南长沙410083 [3]长沙矿山研究院有限责任公司,湖南长沙410012 [4]金属矿山安全与健康国家重点实验室,安徽马鞍山市243000

出　　处：《矿业研究与开发》2019年第6期41-46,共6页Mining Research and Development

基　　金：国家重点实验室开放课题资助项目(2017-JSKSSYS-03)

摘　　要：针对湖北宜昌某磷矿重选尾矿产出量远远低于充填骨料需求量及磷石膏堆放造成环境污染的问题,在磷石膏及重选尾砂物理化学性质分析的基础上,进行了基于磷石膏和重选尾砂的多骨料配比试验,探究了不同养护龄期下充填体的强度演化规律;并利用电镜扫描(SEM)呈现了磷石膏胶结充填体的微观结构,揭示了磷石膏胶结充填体作用机理。研究结果表明:单独采用磷石膏作为骨料时,早期强度较低,添加重选尾矿可明显加快充填体的固结速度,同时充填体的早期及中期强度也相应增大,灰砂比1∶10、磷石膏∶重选尾矿为3∶2,质量浓度70%状态下,试块的7d强度可达1.35MPa,28d强度可达2.67MPa。基于磷石膏和重选尾砂的多骨料充填体的早期强度增长平稳,增长较快,且强度较高,中期强度可达到后期强度的50%左右,多骨料充填体的强度增长相对稳定。Based on the problems that the gravity-separation tailings production of a phosphorus mine in Yichang,Hubei Province was far lower than the filling demand and the environmental pollution was caused by the stacking of phosphogypsum,the physical and chemical properties of phosphogypsum and gravity-separation tailings were analyzed firstly.Then,the multiaggregate ratio test based on phosphogypsum and gravity-separation tailings was carried out to explore the strength evolution rules under different curing ages.Finally,the microstructure of phosphogypsum cemented backfill was observed by scanning electron microscope(SEM),and the mechanism of phosphogypsum cemented filling was revealed.The results showed that the early strength was low when the phosphogypsum was only used as an aggregate.The consolidation speed of filling body can be obviously accelerated by adding tailings,and the early and mid-term strength of backfill also increased correspondingly.The strength can reach 1.35 MPa in 7 days and 2.67 MPa in 28 days with the cement-tailings ratio of 1∶10,phosphogypsumtailings ratio of 3∶2 and mass concentration of 70%.The early strength of multi-aggregate filling body based on phosphogypsum and gravity-separation tailings increased steadily and rapidly.The mid-term strength can reach about 50%of the long-term strength,with a relatively stable trend.

关 键 词：磷石膏 重选尾砂 充填料配比 充填体强度 电镜扫描 

分 类 号：TD853.34[矿业工程—金属矿开采]