多因素影响下尾矿库坝体沉积特性的试验研究

Experimental study on deposition characteristics of tailings dam body influenced by multiple factors

为了研究尾矿颗粒的沉积特性,基于四川某尾矿库进行颗粒取样,并利用室内筛分试验和恒定水流理论对尾矿颗粒的沉积特性进行分析。研究结果表明:干滩面上的沉积规律宏观上表现为前粗后细的规律,并可概化为"粗化—缓慢细化—细化"的变化过程,局部位置出现粒径的突变;干滩面上不同位置均出现了临界粒径,而该粒径的出现标志着某一粒径尾矿含量的显著增多;堆积坝体的颗粒粒径整体呈上粗下细的规律,不同深度位置有夹层、互层、交错层等现象出现;尾矿颗粒的分离流速随着尾矿粒径的增大而变小,而重力与水流拖拽力呈三次线性关系;当选矿工艺一定时,尾矿颗粒在干滩面上的沉积与颗粒流速成正比,和干滩坡度、尾矿粒径成反比。

In order to study the deposition characteristics of tailings particles,the particles sampling was carried out based on a tailings reservoir in Sichuan,and the deposition characteristics of tailings particles were analyzed by using the indoor screening experiments and the constant flow theory. The results showed that the deposition laws on the surface of dry beach macroscopically presented as the first coarse and then fine,and could be generalized to the change process of ＂coarse-slow refinement-refinement＂,with the mutation of the particle size at the local positions. The critical particle size appeared at different positions on the surface of dry beach,and the appearance of this particle size reflected the significant increase of the tailings content with a certain particle size. The particle size of the accumulation dam body presented the laws of upper coarse and lower fine as a whole,and the phenomena of interlayer,interbedding and cross-bedding appeared at different depths.The separation flow velocity of the tailings particles decreased with the increase of the tailings particle size,and the gravity had a cubic linear relationship with the drag force of water flow. The derivation formula showed that when the mineral processing technology was fixed,the deposition of tailings particles on the surface of dry beach was directly proportional to the particle velocity,and was inversely proportional to the slope of dry beach and the tailings particle size.