Impact of Water Chemistry on Tailings Treatment and Consolidation
Water chemistry can influence tailings settling and consolidation. While some of these effects are known, particularly for sand-dominated deposits like CT/NST, what is less well known are the effects of water chemistry on tailings treatment and consolidation for fines-dominated deposits when flocculants like poly acrylamide are used. Improved understanding of the effects of water chemistry on the treatment, de-watering and consolidation of polymer-treated tailings should improve the ability to predict and control commercial deposits. Further, it is important that any tailings water treatment minimizes any detrimental impact on extraction efficiency.
Modelling to Improve Predictions of Commercial Deposit Consolidation
Members require improved prediction and management of deposit properties including sand dominated, fines dominated, flocculated, and centrifuged tailings deposits. The modeling and prediction of consolidation behavior should be based on initial deposition properties (thickness, PSD, treatment method, initial density, etc.). Industry desires to reduce the uncertainty in predicting trajectories of tailings deposit properties so that plans can be developed with higher degree of confidence about when deposits will be fully consolidated.
Clay Chemistry Impacts on Permeability and Consolidation of Fines-Dominated Deposits
Improved understanding of the effects of clay types on permeability and consolidation of polymer-treated fine tailings, resulting in improved prediction of tailings processes, deposit modeling and adaptive management of tailings deposits.
Environmental Performance Assessment for Froth Treatment Tailings Affected Material
Quantification of environmental effects related to froth treatment tailings specific constituents of potential concern, i.e. residual diluent, acid rock drainage precursors and naturally occurring radioactive materials.
Impact of Residual Bitumen on Tailings
Understanding the effect of residual bitumen on tailings treatment, settling, and consolidation and drying, particularly for treatment and deposition of FFT and the geotechnical effects asphaltenes in the deposit can have.
Optimize Flocculants/Coagulant Suite and Dosage to Improve De-Watering
Understanding the science underpinning coagulant and flocculent use in tailings treatment including investigating different types of coagulants, different types of flocculants and optimum combinations of these for a wide range of tailings from sand-dominated to fines-dominated slurries.
Commercially Ready Online Instrumentation
Real-time, on-line or at-line analyzers that will measure directly – or by inference – all the key characteristics of tailings streams needed to control tailings treatment processes. Key characteristics could include bitumen content, clay content, density, segregation/dewatering potential, Sands-to-Fines Ratio (SFR), floc size, PSD, rheology, electrical and hydraulic conductivity and yield stress. Tailings treatment processes include optimal use of flocculants and/or coagulants when added to fluid fine tailings streams or control of processes used to produce processed tailings.
Improve and enhance the understanding for drying for sub-aerial deposits, including atmospheric drying and freeze thaw.
Capping of Tailings Deposits
Refine existing methods and best practices and develop novel techniques for stabilization, capping, and reclamation of tailings deposits including CT/NST, thick fines-dominated deposits (TT, Centrifuge cake, polymer-treated FFT).
Accelerate the speed at which initial settling and subsequent consolidation of tailings deposits progress. This will ultimately enhance the storage efficiency, water recovery and reuse, and subsequent deposit reclamation activities ensuring the objective of Tailings Management Framework (TMF) are met.
Co-Deposition of Tailings Streams
Optimizing the ratio of different tailings streams and the design of co-deposition cells to increase the initial strength and facilitate water release and consolidation.
In Situ Amendments to FFT and Soft Tailing Deposits
Environmentally effective means of in situ reclamation for soft tailings deposits to create boreal forest landforms including terrestrial, wetland and aquatic reclamation features.
Collection of (Harvesting) FFT
Two primary areas for attention in FFT harvesting system improvements:
i. More effective debris management to reduce system outages attributable to debris blockages at suction intake and downstream in FFT flocculation and processing operations.
ii. Reduce dilution of FFT due to 'coning' of FFT near suction intake and subsequent influx of overlying thin FFT and water. Seek techniques, equipment, and operating procedures to eliminate unplanned dilution associated with coning.
Effects of Transportation of Tailings Slurries
The deposit performance for both sand-dominated and fines-dominated tailings slurries can be greatly affected by the transportation and deposition method. It is important to understand how the rheology of the material is affected by shear during transportation. It is also important to optimize deposition techniques and practices to minimize segregation on tailings beaches for a variety of tailings slurries.