Simulation of water storage in a reclamation cover incorporating tailings consolidation

Abstract

Successful reclamation of mine tailings requires effective management of the contaminated water generated by the consolidation of tailings over time. Due to uncertainty in predicting consolidation-induced water release, mine planners often use simulation models to prepare for a range of anticipated scenarios. This paper describes the development of the Tailings Management Simulation Consolidation model (TMSim-Consol) using the GoldSim software. TMSim-Consol simulates tailings settlement over time and the upward flow of pore water due to consolidation. The advantages of using system dynamics simulation tools are illustrated by the inherent transparency of the numerical method to end users. A hypothetical reclamation set-up consisting of an oil sands thickened tailings (OSTT) deposit capped by a sand layer was simulated under a range of initial tailings properties. The simulation results showed that soil water storage in the sand cap was highly sensitive to the initial solids contents of the underlying OSTT. To limit the release of contaminated water at the surface, the initial solids content of OSTT needs to be at least 65% before sand capping.

Estimating the Potential Differential Settlement of a Tailings Deposit Based on Consolidation Properties Heterogeneity

“…A 1D large strain consolidation model based on Gibson's theory was developed by [29,30], which is the primary input to the quasi-3D tailings surface contour model in this paper. Zheng's model simulates the consolidation of a column of deposited tailings and generates a height interface of the column over time, using System Dynamics techniques in the GoldSim environment.…”

“…The 1D large strain consolidation model developed by [30] is the basis for the developed methodology of this paper. The 1D model implements a finite difference scheme [40,41] to solve the large strain model with Gibson theory [13] using System Dynamics (SD) techniques.…”

“…The performance of a proposed model can be validated through comparing the model results against the real field data, or the results of available software packages that are already validated through different benchmarks. The 1D model component of the proposed consolidation model is validated by [29,30] through three sets of scenarios, based on the reported cases by [27] as the well-accepted benchmarks. The benchmark cases have been widely used in the literature for evaluation of numerical large strain consolidation models, and are the results of nine different models that predicted the consolidation behavior of four waste clay disposal scenarios [23].…”

“…The benchmark cases have been widely used in the literature for evaluation of numerical large strain consolidation models, and are the results of nine different models that predicted the consolidation behavior of four waste clay disposal scenarios [23]. In [29,30], the authors simulated the tailings consolidation under different permeability and compressibility conditions for three types of tailings, i.e., untreated mature fine tailings (MFT), thickened tailings (TT) and phosphate tailings (PT). The authors considered a wide range of solid contents and initial deposit height to investigate the robustness of the model.…”

“…The objective of this paper is to develop a framework for estimating the differential settlements of a consolidating tailings surface based on a series of adjacent consolidating 1D columns. This has been done through implementing a large strain consolidation model developed by [29,30]. The performance and utility of the developed model in this paper is demonstrated through several scenarios using a synthetic tailings deposit dataset.…”