复合胶凝剂在贵州云峰铝土矿充填膏体中的应用研究

Application of Composite Gelling Agent in Filling Paste of Yunfeng Bauxite in Guizhou Province

为促进工业废渣的资源化利用和降低充填采矿的碳排放,采用水泥-矿渣-赤泥复合胶凝剂对贵州云峰铝土矿充填料浆进行改性,对充填体试件开展了抗压强度、抗折强度、收缩率、渗透率、抗冻融耐久性测试与微观结构观测,分析了胶凝剂掺量对充填体性能的影响规律及其机理,并结合现场观察评价了充填采矿的经济效益。结果表明:相较于单掺水泥的充填膏体试件,经赤泥和矿渣微粉改性的试件的抗压强度、抗折强度、干燥收缩性、抗渗性能与抗冻融耐久性均显著提高;当复合胶凝剂中的水泥、矿渣和赤泥质量比为2∶1∶1时,充填膏体的各项性能达到最佳;采用复合胶凝剂能够促进胶凝材料的水化反应和微集料反应,进而提升充填膏体的物理力学性能。贵州云峰铝土矿自流充填平台的应用实例表明,采用水泥-矿渣-赤泥复合胶凝剂改性充填膏体,提高了固废资源化利用效率,同时可创造显著的经济效益。

In order to promote the resource utilization of industrial waste slag and reduce the carbon emission of filling mining,cement-slag-red mud composite gelling agent was used to modify the filling slurry of Yunfeng Bauxite Mine in Guizhou Province.Compressive strength,flexural strength,shrinkage rate,permeability,freeze-melt resistance durability tests and microstructure observation were carried out,and the influence rule and mechanism of cementing agents on backfill properties were analyzed.Combined with the field observation,the economic benefit of filling mining was evaluated.The results show that the compression strength,flexural strength,dry shrinkage,permeability resistance and freeze-thaw durability of the specimens modified by red mud and slag powder are significantly improved compared with the single cement paste specimens.When the mass ratio of cement,slag and red mud in the composite gelling agent is 2∶1∶1,the properties of the filling paste reach the best.The use of composite gelling agent can promote the hydration reaction and micro-aggregate reaction of the gelling material,and then improve the physical and mechanical properties of the filling paste.The application example of the self flow filling platform in Yunfeng Bauxite Mine shows that using cement-slag-red mud composite gelling agent to modify the filling paste improves the efficiency of solid waste resource utilization and can create significant economic benefits.