全尾砂絮凝沉降试验及其工程应用

Flocculating Sedimentation Test of Unclassified Tailings and Its Engineering Application

充填料浆制备是膏体充填采矿方法的重要组成部分,而尾砂高效浓缩是膏体充填的核心。由于全尾砂粒径很细,尾砂沉降浓缩也变得十分困难,因此,在尾砂料浆中加入絮凝剂是提高沉降浓缩速率的有效手段。由于室内试验环境和条件与地下采场存在很大不同,为了揭示新城金矿全尾砂絮凝沉降特性,不仅开展了全尾砂静态絮凝沉降室内试验,以沉降速度、底流浓度为评价指标,得到了最优的絮凝剂选型、单耗和砂浆浓度参数,确定了上述参数对于尾砂料浆沉降效率的影响规律,还在地下采场进行了现场工业试验对比分析,以验证加入该组合参数絮凝剂后的实际应用效果。室内试验结果表明:料浆底流浓度随着料浆稀释浓度的增加先增加后减小,而在絮凝剂单耗低于22.5 g/t时变化不大,因此选定絮凝剂型号为ZYJ、絮凝剂添加量为20 g/t、矿浆稀释浓度为9.75%时,室内尾砂料浆的絮凝沉降效果最佳。现场对比试验表明:采用该最佳试验参数组合后,充填溢流水中悬浮物质量浓度由5.32%~8.26%降低到1.15%~2.13%,充填体强度增加了13%,且整体分布更加均质,充填效果和充填质量均有明显改善。

The preparation of slurry is an important part of cemented paste filling mining method,and the effective sedimentation of tailings slurries is the core of this technology.As unclassified tailings have smaller particles,the slurry sedimentation become more difficult.As a result,it has been a common measure of adding flocculant in the slurries to increase sedimentation efficiency.As there are great difference exist between the laboratory experimental environment and the underground stope.In order to reveal the flocculating settlement characteristics of the unclassified tailings in Xincheng Gold Mine,the static flocculation sedimentation experiment of unclassified tailings was carried out.The sedimentation velocity and the underflow concentration were used as the evaluation indexes to determine the optimal flocculant selection,unit consumption and slurry concentration parameters,and the effects of these factors on the sediment efficiency were obtained.Moreover,the engineering application was carried out in the field.Laboratory test results show that the underflow concentrations first underwent increase and then decrease with the slurry concentration gains,while kept almost unchanged when the added flocculant was less than22.5 g/t.In addition,the flocculant type ZYJ,flocculant dosage 20 g/t and slurry dilution concentration 9.75% have the best flocculation sedimentation performance.Field comparison tests show that the concentration of suspended solids decreases from5.32%~8.26% to 1.15%~2.13%,the strength of specimens increases by 13%,and the overall distribution is more homogeneous,which indicate that the filling effect and quality are improved significantly.