基于超细磷尾砂的絮凝沉降特性及其胶结膏体充填材料性能研究

Study on flocculation sedimentation characteristics and cementedpaste backfill materials properties based on ultrafine phosphorus tailings

目的:本研究旨在提高基于矿山超细磷尾砂的充填质量、效率和经济效益。方法:本研究基于磷尾砂的物化特性,通过控制絮凝剂用量和入料浓度,研究了磷尾砂在絮凝沉降过程中的最佳条件;并通过调整充填料浆的质量浓度和砂灰比,分析了这些因素对充填料浆流动性和充填体力学性能的影响。结果与结论:研究结果表明,超细磷尾砂的最佳絮凝沉降入料浓度为10%,在聚丙烯酰胺用量为25 g/t时,底流浓度可达64.53%。磷尾砂胶结充填料浆的流动性主要由屈服应力决定,其受质量浓度影响较大,受砂灰比影响较小。水泥对超细磷尾砂的固化效果有限。研发针对超细磷尾砂的低成本充填胶凝材料是提升充填体性能的关键途径。意义:本研究为提高基于矿山超细磷尾砂的充填质量、效率和经济效益提供了最佳工程参数和有效途径,具有重要的工程指导意义和应用价值。

Purpose:This study aims to improve the quality,efficiency,and economic benefits of using ultrafine phosphate tailings in mining backfill operations.Method:Based on the physicochemical properties of phosphate tailings,this study investigates the optimal conditions for their flocculation and sedimentation by controlling flocculant dosage and feed concentration.Additionally,it examines the effects of varying solid concentrations and sand-to-cement ratios on the flowability of the backfill slurries and the mechanical properties of the backfill mass.Result and Conclusion:The results indicate that the optimal feed concentration for flocculation and sedimentation of ultrafine phosphate tailings is 10%.With a polyacrylamide dosage of 25 g/t,the underflow concentration can reach 64.53%.The flowability of the backfill slurry,which is based on these phosphate tailings,is primarily determined by yield stress,being significantly influenced by the solid concentration and less by the sand-to-cement ratio.The solidification effect of cement on ultrafine phosphate tailings is found to be limited.Developing low-cost cementitious materials specifically tailored for ultrafine phosphate tailings is essential for improving the performance of the backfill mass.Significance:This study provides optimal engineering parameters and effective methods to improve the quality,efficiency,and economic benefits of backfilling using ultrafine phosphate tailings,offering significant engineering guidance and practical value.