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

对阿尔伯塔油砂尾矿的快速脱水技术迫切需要，但目前还没有成熟的技术。快速脱水使热工艺水能够快速回收，并产生可堆放的可回收尾矿。这种技术可以消除对大型尾矿库的需求，显著降低淡水消耗，降低将淡水加热到50°C左右的能耗和温室气体排放。通过由帝国石油公司赞助的初步测试项目，我们最近证明了通过低剂量化学改性和Volute螺旋压榨处理相结合，成功地脱水油砂流体细尾矿（FFT， 21%固体，砂细比（SFR）为1.0）。例如，将化学改性的fft以14.3 kg /h的速度送入Volute螺旋压力机，连续稳定地在出料饼中产生65-72 wt%的固体，在滤液（即工艺水）中产生0.2 wt%的固体。结果超过了目前油砂工业中FFT脱水的目标固含量（即60% wt%），而从Volute螺旋压榨机中提取的滤液可以直接再利用，无需进一步处理。目前的提案是研究的延续。在拟议的项目中，我们将评估强化混凝-絮凝剂化学加涡旋压机在一系列油砂尾矿中的应用和商业潜力，包括具有不同SFRs和固体含量的流体细尾矿（FFTs）、稠化尾矿（TT）和尾矿-溶剂-回收装置（TSRU）尾矿。从该项目中获得的结果和知识将使拟议的Volute螺旋压力机技术符合阿尔伯塔省能源监管机构的指令085，从而产生阿尔伯塔省油砂尾矿的快速脱水技术。

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.