The mining of aggregates or mineral ores 这些材料的后续加工以提取所需菠菜网最稳定正规平台_最全菠菜网大全通常会产生一种称为尾矿的无价值部分.
When extracting rich veins of highly concentrated materials, the tailings fraction can be very low, 但人类采矿活动的长期历史已经耗尽了许多高度集中的骨料和矿床.
Today, with high volume mining/processing operations, especially when mining precious and trace minerals, 产生的尾矿量可大于所采菠菜网最稳定正规平台_最全菠菜网大全的90%.
Old methods for handling tailings
骨料和矿物工业历来使用最简单和最便宜的方法 manage waste slurry tailings. The oldest methods include dumping directly into streams, 河流和湖泊，或使用采矿表面或地下采石场/坑进行处置.
Since the middle of the 20th century, 这些行业一直受到压力，要求淘汰旧的废物倾倒方式，寻找更安全的方式, environmentally friendly and efficient technologies. 目前管理尾矿最常用的方法是将稀释或浓缩的尾矿浆储存在池塘或蓄水坝中.
Unlike large hydroelectric water dams, 建设尾矿库是为了永久储存矿山固体废尾矿. At the beginning of the 21st century, there were an estimated 3,500 tailings containment ponds globally. 建造的一些最大的遏制池直径超过几英里，深数百英尺.
New technology for managing tailings
Until the past 10 years, 关于这些尾矿坝的成功和失败率的记录很少. 由于本世纪发生了几次灾难性的大型尾矿库破坏, 目前更加注意进一步改进尾矿管理做法.
In addition to the loss of up to several hundred human lives, 这些重大的遏制失败破坏了大片土地，造成了严重的地面和水路污染. Furthermore, 由于环境法规的收紧，改善尾矿管理的压力正在加大, better understanding of the high operating cost, 减少废物处理费用的需要和日益需要改善节约用水.
这些压力迫使行业领导者评估并更好地了解其尾矿管理的整个生命周期成本. Based on this knowledge, 积极主动的公司现在证明了在改善尾矿管理系统方面的前期投资是合理的. Some of the more common improved tailing management systems include:
Underground tailings backfill with:
- Paste thickened tailings pumped underground.
- Thickened tailings mixed with cement placed underground.
Aboveground tailings placement with:
- Paste thickened tailings pumped into a pond or impoundment.
- Thickened tailings mixed with cement and dry stacked.
- Thickened and dewatered tailings dry stacked.
Underflows from a Paste Thickener.
在大型尾矿库中放置膏体浓缩尾矿库是近20多年来改善尾矿库管理的最常见做法. Paste thickening 是否与其他重力沉降浓缩技术相似，但会产生更高的尾矿浓度, 与旧的非浓缩储存方法相比，减少了在尾矿库中储存的材料体积的70-80%.
To reduce the tailings volume further, 必须采用脱水技术，在将浓缩的尾矿浆放入围堵池之前除去额外的水.
Dewatering technologies can reduce tailings volume an additional 5-10%, but more importantly, sufficient water is removed creating a dry, stackable material. Dewatered tailings can still contain 10- 20% moisture, but the material behaves more like a solid, making it possible to dry stack the tailings in containment areas. After being placed in the containment areas, the low-moisture tailings are very stable, significantly reducing safety and environmental risks.
已经存在了几十年甚至几百年的常见脱水技术正在被评价和应用于尾矿脱水. Some of these technologies include:
- Plate filter presses
- Vacuum belt filters
- Belt filter presses
- Centrifuges
Recessed/Membrane Plate Filter Press technology 已被发现是浆体尾矿脱水最有效的方法之一。 recovering the maximum amount of water and generating the driest cakes. 虽然板式压滤机的资金成本与其他技术相比较高, the operating costs are much less.
常用脱水技术的相对前期投资和持续运行成本如下所示.
Advantages of dry stack tailings
行业领导者发现，干堆尾矿比旧堆尾矿具有许多优势, 不太理想的方法，尽管潜在的增加前期和持续的成本.
Improve structural stability of material storage
干堆式尾矿库大大提高了物料库的结构稳定性, especially in high seismic rated zones, 靠近人口密集的中心或高度敏感的环境区域.
Maximum recovery of recycled water
In the most arid regions of the world, 干堆尾矿允许回收最大量的循化水. 增加循环水的使用可以帮助大大降低高度管制和稀缺的水源成本.
Clear water recovered from a Filter Press.
Recovery of residual process chemicals
干堆尾矿还促进了可从循化水中回收的残余工艺化学品的回收.
Most effective physical storage
Especially in locations with limited available space, dry stack tailings offer the most effective physical storage. 干堆尾矿最大限度地减少了许可的复杂性，并最大限度地减少了附近社区公众关注的可能性.
Drip-free, dewatered cakes discharge from a Filter Press into a pile.
干堆尾矿管理是一种越来越被接受的做法，因为随着年龄的增长，灾害经常发生, 非浓缩和更常规的浓缩尾矿储存设施. 人类生命的悲惨损失以及对大片土地和社区的重大环境和物理破坏正在加速发展更稳定的干堆尾矿许可和做法.
将经济价值赋予干堆尾矿的所有潜在优势，开始证明高效脱水设备的较高前期资本投资成本是合理的. 行业领导者开始认识到，在考虑矿山的整个生命周期时，可以抵消较高的前期投资和运营成本, including the ongoing tailings management cost after the processing facilities are closed.
