Partially Hydrophobic and Natural Graft Polymers for the Efficient Treatment of Mature Fine Tailings

今天，在克拉克热水提取法首次用于从油砂中提取沥青的50多年后，油砂行业仍在处理被困在尾矿池中的大量水。尾矿是一种由30%粘土和70%水组成的混合物，是油砂开采过程中不希望产生的副产品。2016年7月，艾伯塔省能源监管机构发布了第085号指令，实施了尾矿管理框架。第085号指令规定，油砂尾矿必须在其项目生命周期内持续处理，以便尾矿库占用的土地可以在矿山生命周期结束后的10年内进行复垦。目前用于处理尾矿的现有化学（混凝剂和絮凝剂）和机械（离心、薄提升干燥、深沉淀）方法的有效性有限。因此，为了满足油砂工业的土地复垦目标，这些方法需要取得重大进展。聚丙烯酰胺絮凝剂通常用于处理尾矿，但其应用受到其溶液高粘度的限制，这使得它们难以剂量和处理。这种技术产生的絮凝体在通过管道从处理站泵送到沉淀点时也可能破裂。此外，聚丙烯酰胺在处理后的尾矿中保留了大量的水，这些水不会干燥到足以进行土地复垦。目前的研究计划将使用两种不同但互补的方法来解决聚丙烯酰胺絮凝剂的局限性：1)改性天然聚合物和2)部分疏水（在尾矿沉积物中不保留水）聚合物。我们还将结合这两种方法的优点，在这个提案中我们称之为混合聚合物。

Today, more than 50 years after the Clark Hot Water Extraction Process was first used to extract bitumen from oil sands, the oil sands industry is still dealing with vast volumes of water trapped in tailing ponds. Tailings, a mixture of about 30% clays and 70% water are a undesired by-product of the oil sands extraction process.In July 2016, the Alberta Energy Regulator issued Directive 085 implementing the Tailings Management Framework. Directive 085 mandates that oil sands tailings must be continually treated during their project lifetime so that the land occupied by tailing ponds is ready to be reclaimed within 10 years of the end of the mine lifetime. Existing chemical (coagulants and flocculants) and mechanical (centrifugation, thin lift drying, deep deposits) methods currently used to treat tailings have limited effectiveness. Consequently, significant advances in these methods are needed to meet the land reclamation targets for the oil sands industry. Polyacrylamide flocculants are typically used to treat tailings, but their application is limited by the high viscosity of their solutions, which makes them difficult to dose and handle. Flocs generated with this technology may also break when they are pumped through pipelines from the treatment station to the deposition site. In addition, polyacrylamide retains substantial amounts of water in the treated tailings, which do not get dry enough to allow for land reclamation. The current research proposal will address the limitations of polyacrylamide flocculants using two different, yet complementary, approaches: 1) modified natural polymers, and 2) partially hydrophobic (which do not retain water in the tailing sediments) polymers. We will also combine the advantages of these two approaches in what we call hybrid polymers in this proposal.