全尾砂沉降特性试验研究

Experimental study on settlement characteristics of full tailings

国内某矿山目前主要采用戈壁集料作为充填骨料,随国家新环保政策的发布,戈壁集料价格大幅度上涨,且面临无法采购的风险,将尾砂用于矿山充填是有效的解决途径。尾砂沉降浓缩是尾砂充填的关键环节,通过开展尾砂的自然沉降和絮凝沉降试验研究该矿尾砂的沉降特性。试验结果表明:尾砂自然沉降速率随尾砂浆浓度的增大而减小,底流浓度随尾砂浆浓度的增大呈先增大后趋于稳定;沉降速率随絮凝剂添加量的增大而提高,底流浓度随絮凝剂添加量的增大而降低;尾砂虽然颗粒细小,但因其密度较大,尾砂浆浓度较低时,其静态自然沉降速率可以达到1.5cm/min以上,絮凝剂能够较大地提高低浓度尾砂浆的沉降速率,其对高浓度尾砂浆的沉降速率影响效果不明显。

Gobi aggregates are mainly used as filling aggregates in a domestic mine currently.With the posting of the national new environmental protection policy,the price of Gobi aggregates has increased significantly,and faces the risk of being unable to purchase.An effective solution is to use tailings for mine filling.The sedimentation and concentration of tailings are the key links of railings filling.The sedimentation characteristics of the full tailings were studied by conducting the natural settlement and flocculation sedimentation tests.The test results indicated that the natural sedimentation rate of railings decreased with the increase of tailings concentration.The concentration of underflow increased firstly and then stabilized with the increase of tailings concentration.The sedimentation rate increased with the increase of the addition amount of floceulant.The concentration of underflow decreased with the increase of floeeulant addition.Although the particle size of the tailings is small,the static natural sedimentation rate can reach 1.5cm/min or more when the concentration of the railings slurry is low for the tailings with high density.The floceulant can greatly increase the sedimentation rate of tailings slurry with low concentration,but has unobvious effects on the sedimentation rate of tailings slurry with low concentration.