Development of a small-scale geotechnical centrifuge

Oil sands fluid fine tailings in Northern Alberta have very poor water release characteristics and require many decades to fully consolidate under their own weight. Generally, physical and/or chemical treatments are necessary to improve the consolidation behaviour and manage the tailings in an economical and environmentally acceptable manner. The effect of each treatment method is commonly evaluated, in part, by measuring the short- and long-term consolidation behaviour of treated samples. Geotechnical beam centrifuges, large strain consolidation apparatus, and geocolumns are typically used to measure the consolidation properties. However, these methods require many months to complete or are expensive and difficult to deploy in the field. We developed a small-scale geotechnical centrifuge suitable for use in both research environments and laboratories at industrial sites to study and/or monitor various treatment and disposal options in a short time. This paper presents the motivation for developing a small-scale centrifuge, the components and features of the centrifuge, and the assortment of tests completed to validate the apparatus and testing methods. The validation tests proved that the small-scale centrifuge produces comparable results to existing methods while reducing the cost and time required to evaluate the consolidation performance of different tailings treatment options.