摘要
将重介质选矿产生的磷尾矿破碎至5 mm以下后与粉煤灰、水泥按一定比例混合制备胶结充填材料。通过X射线衍射(XRD)、综合热分析(TG/DSC)、扫描电镜(SEM)等技术手段,对磷尾矿和粉煤灰的化学成分和矿物成分进行分析,对优化配比的胶结充填材料不同龄期的力学性能与水化过程的关系进行研究。结果表明:磷尾矿受粒径和活性物质的影响,活性较低。而粉煤灰具有一定的火山灰活性。胶结充填材料的水化反应包括:水泥的水化反应,粉煤灰、少量磷尾矿的火山灰反应。以上水化反应生成的钙矾石(AFt)和水化硅(铝)酸盐(C-S-H)凝胶与分散的磷尾矿、未反应的粉煤灰等联结起来,构成牢固紧密的整体,具有较好的力学性能。
Coarse phosphate tailings produced by dense media separation were crushed to-5 mm. And then treated coarse phosphate tailings,fly ash and cement were mixed according to a certain proportion to prepare cemented paste backfilling materials. The chemical compositions and mineral compositions of coarse phosphate tailings and fly ash were characterized by XRD,AG/DSC and SEM,respectively. The hydration products of cemented paste backfilling materials with 28-day instars were firstly studied and then the micro topographies of the hydration products with different instars were also studied. The experimental results indicate that the activity of the coarse phosphate tailings is low,which is mainly influenced by grain size of the coarse phosphate tailings and active substances. Moreover,fly ash has great pozzolanic activity. The hydration reactions of cemented paste backfilling materials include the hydration reaction of cement,as well as pozzolanic reaction between fly ash and partial coarse phosphate tailings. The generated Aft and hydrated silicate（ aluminate） hydrate（ C-S-H） bounded with dispersive coarse phosphate tailings and unreacted fly ash,constitutes a firm entirety with good mechanical properties.
出处
《武汉理工大学学报》
CAS
北大核心
2017年第3期22-26,共5页
Journal of Wuhan University of Technology
基金
湖北省自然科学基金(2014CFA529)
关键词
磷尾矿
胶结充填材料
力学性能
水化过程
phosphate tailings
cemented paste backfilling materials
hydration
pozzolanic reaction
作者简介
李延杰（1991-），男，硕士生．E—mail：l1iyanjie19910526@163．com;通讯作者：梅甫定（1964-），男，教授．E-mail：mfd1964@sohu．com
