High Fines Sand Tailings as a Novel Oil Sands Tailings Treatment Technology

从加拿大的油砂中提取沥青会产生大量的流体细尾矿（FFT），这是一种对固结和修复提出重大环境和经济挑战的废料。截至2019年，尾矿库存超过1，270立方米，寻找负责任的尾矿管理解决方案是加拿大采矿业的首要任务。 巴斯夫化学公司开发了一种新技术，将粗砂粒与FFT结合成由细颗粒组成的材料，填充连续较大颗粒之间的间隙空隙。 所得基质的分形性质-称为“高细砂尾矿”（HFST）-非常类似于原始油砂矿。巴斯夫的产品开发测试和NAIT的独立验证表明，HFST可以创建完全集成的砂/细粒基质，并且比其他砂基尾矿处理策略（如复合尾矿（CT））更能抵抗剪切密集型工艺条件。与CT不同的是，在CT中，细粒从处理过的材料中分离是常见的，高释放水澄清度是巴斯夫技术的标志。虽然HFST已被证明在严格控制的实验室规模条件下具有最佳性能，但它还必须被证明在现场条件下表现出色。几个尾矿属性，如固体含量，粘土分数，和水化学，被理解为影响絮凝过程。然而，尾矿操作通常很少或没有过程控制，这意味着任何可行的处理方法必须是稳健的，并在广泛的条件下提供良好的性能。本研究的重点是确定HFST的操作窗口，然后在随后的更大规模应用的学习。首先，将以1 m ³/hr的进料流速进行小规模试验，然后进行全规模现场试验，以200 m ³/hr处理FFT。此外，HFST释放的水将用于从油砂矿中提取沥青，并与现有工艺用水进行沥青回收性能比较。该项目还将评估HFST技术处理油砂行业以外的新鲜油砂尾矿流或矿山废物的能力。

Extracting bitumen from Canada's oil sands generates large volumes of fluid fine tailings (FFT), a waste material that presents significant environmental and economic challenges to consolidation and remediation. With over 1,270 Mm³ of tailings inventory as of 2019, finding a responsible solution to tailings management is a top priority for the Canadian mining industry. Chemical company BASF has developed a novel technology that combines coarse sand grains with FFT into material composed of fine particles filling the interstitial voids between successively larger particles. The fractal nature of the resultant substrate - known as "High Fines Sand Tailings" (HFST) - closely resembles the original oil sand ore. Product development testing at BASF and independently verified at NAIT have shown that a completely integrated sand/fines matrix is created with HFST, and much more resistant to shear-intensive process conditions than other sand-based tailings treatment strategies such as Composite Tailings (CT). Unlike CT, where the undesirable segregation of fines from the treated material is common, high release water clarity is a hallmark of the BASF technology. While HFST has been demonstrated to give optimal performance under tightly controlled laboratory-scale conditions, it must also be proven to excel under field conditions. Several tailings properties, such as solid content, clay fraction, and water chemistry, are understood to impact the flocculation process. However, tailings operations are often run with little to no process control, meaning that any viable treatment method must be robust and provide good performance over a wide range of conditions. The present study focuses on determining the operating window for HFST, then applying the learnings in subsequently larger scales. First, a small-scale pilot will be conducted at a feed flow rate of 1m³/hr before proceeding to a full-scale field pilot, treating FFT at 200m³/hr. Moreover, the water released from HFST will be used to extract bitumen from oil sand ore, with bitumen recovery performance compared against incumbent process water. The project will also evaluate HFST technology's ability to treat a fresh oil sands tailings stream or mine wastes outside of the oil sands industry.