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液体细尾矿(FFT)，这是一种废物，给固结和修复带来了巨大的环境和经济挑战。截至2019年，加拿大尾矿库存已超过1270毫米，找到负责任的尾矿管理解决方案是加拿大采矿业的当务之急。化学公司巴斯夫开发了一种新技术，将粗沙颗粒和快速傅立叶变换结合在一起，形成由细颗粒组成的材料，填充在连续较大颗粒之间的间隙中。形成的底物--被称为“高粉砂尾矿”(HFST)--的分形性质与原始的油砂矿石非常相似。巴斯夫的产品开发测试和NAIT的独立验证表明，使用HFST可以创建完全集成的砂/细颗粒基质，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，在CT中，从处理后的材料中分离出不受欢迎的细粉是常见的，高释放水透明度是巴斯夫技术的一个标志。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，但它也必须被证明在现场条件下表现出色。据了解，尾矿的几个性质，如固体含量、粘土含量和水化学，都会影响絮凝过程。然而，尾矿作业通常在很少或没有过程控制的情况下运行，这意味着任何可行的处理方法都必须是稳健的，并在各种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，然后在随后的更大范围内应用所学到的知识。首先，将进行小规模试验，进料速度为1m³/小时，然后进行全面的现场试验，以200m³/小时的速度处理FFT。此外，HFST排放的水将用于从油砂矿石中提取沥青，与现有工艺水相比，沥青回收性能更佳。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.