Dewatering Oil Sands Fluid Fine Tailings by Enhanced Flocculation Chemistry and Volute Screw Press

阿尔伯塔油砂尾矿的快速脱水技术是迫切需要的，但目前还没有。快速脱水能够快速回收热工艺用水，并生成可堆叠的可再生尾矿。这种技术可以消除对大型尾矿池的需求，显著降低淡水消耗，并降低与将淡水加热到约50°C相关的能耗和GHG排放。通过由帝国石油公司赞助的初步试验计划，我们最近证明了通过低剂量化学改良剂和涡卷螺旋压榨处理相结合，对油砂流体细尾矿（FFT，21重量%固体，砂细比（SFR）为1.0）进行脱水的成功。例如，将化学改性的FFT以高达14.3kg-干固体/h的生产量进料至蜗壳螺旋压榨机，连续且一致地在排出滤饼中产生65-72重量%的固体，并且在滤液中产生0.2重量%的固体（即，工艺用水）。结果超过了当前的目标固体含量，以进行FFT（即，60wt%），而涡螺压榨滤液可直接回用于油砂提取工艺，不需进一步处理，本方案是该研究的延续。在拟议的项目中，我们将评估强化混凝剂-絮凝剂化学加上螺旋压榨机在一系列油砂尾矿上的应用和商业潜力，包括具有不同SFR和固体含量的流体细尾矿（FFTs），增稠尾矿（TT）和尾矿溶剂回收单元（TSRU）尾矿。从该项目中获得的结果和知识将使拟议的涡卷螺旋压榨机技术符合阿尔伯塔能源监管机构的085号指令，从而为阿尔伯塔油砂尾矿提供快速脱水技术。

Rapid dewatering technology of Alberta oil sands tailings is urgently needed but currently unavailable. Rapid dewatering enables fast recycling of the warm process water and the generation of stackable reclamation-ready tailings. Such a technology can eliminate the need for large tailings ponds, significantly lower fresh water consumption, and lower energy consumption and GHG emissions associated with heating the fresh water to about 50°C. Through a preliminary test program sponsored by Imperial Oil, we have recently demonstrated the success of dewatering oil sands fluid fine tailings (FFT, 21 wt% solids, sand-to-fine ratio (SFR) of 1.0) by a combination of low-dosage chemical amendment and Volute screw press treatment. For instance, the chemical-amended FFTs were fed to the Volute screw press at up to 14.3 kg-dry solids/h throughput, yielding 65-72 wt% solids in the discharge cakes continuously and consistently and 0.2 wt% solids in the filtrate (i.e., process water). The results exceeded the current target solids content to dewater FFT (i.e., 60 wt%) in the oil sands industry, while the filtrate from the Volute screw press can be reused directly with no further treatment in oil sands extraction process.The current proposal is a continuation of the research. In the proposed project, we will evaluate the application and commercial potential of enhanced coagulant-flocculant chemistry plus Volute screw press on a range of oil sands tailings including fluid fine tailings (FFTs) with different SFRs and solids contents, thickened tailings (TT), and tailings-solvent-recovery-unit (TSRU) tailings. The results and knowledge obtained from this project will position the proposed Volute screw press technology in line with Alberta Energy Regulator's Directive 085, resulting in a rapid dewatering technology for the Alberta oil sands tailings.