Experimental Analysis on Permeability Characteristics of Iron Tailings

Abstract

The permeability characteristics of iron tailings are one of the important factors affecting the stability of the tailings dam. The permeability properties of undisturbed iron tailings and disturbed iron tailings were analyzed from various aspects such as FC value, gradation, particle size, specific surface area, and interparticle void ratio with water head test in laboratory. The results show that the permeability coefficients of undisturbed iron tailings and disturbed iron tailings are affected by the fine particles content (FC). The threshold of fine content is about 40%. The traditional formulas for calculating the permeability coefficient are applied. But the results are inaccurate. The relationship between permeability coefficient of the iron tailings (undisturbed iron tailings and disturbed iron tailings) and the nonuniform coefficient (Cu), the curvature coefficient (Cc), the average particle size, the weighted average particle size, the specific surface area, and the skeleton void ratio (es) is nonlinear. It is difficult to characterize the change of permeability coefficient when the fine content is large. However, the relationship between permeability coefficient of the iron tailings (undisturbed iron tailings and disturbed iron tailings) and the effective particle size and silt particles void ratio (ef) is linear. A formula was developed for the determination of permeability coefficient of iron tailings by analyzing the effective particle size and silt particles void ratio. And it is more accurate. The permeability coefficients of disturbed samples are slightly larger than the permeability coefficients of undisturbed sample. This is due to the destruction of the sedimentary structure of the tailings and increasing e. Maybe the R in the new formula is affected by the structure of iron tailings. This requires further research.

Novel Insights into the Influence of Soil Microstructure Characteristics on the Migration and Residue of Light Non-Aqueous Phase Liquid

“…The Characteristic parameters included Dv10, Dv30, Dv50, Dv60, Dv90, Cu, and Cc [ 27 , 28 , 29 ]. Dv10, Dv30, Dv50, Dv60, and Dv90 represent the soil particles corresponding to 10%, 30%, 50%, 60%, and 90% of volume fraction, respectively.…”

Permeability Prediction of Iron Tailings Including Degree of Compaction and Structure

“…2-1, 2-2, and 2-3 belong to the first type of iron tailings. eir permeability could be calculated by equation (21). e results are shown in Table 1, which becomes more accurate.…”

“…But the permeability coefficients increase slightly, when the silt content exceeds 40%. e reason behind this increasing trend is that the void ratio increases when the silt content exceeds 40% [21]. en, the permeability coefficients continue to decrease because of the increase in clay content.…”

“…Benson et al [29] believe that the permeability coefficient fell off rapidly when the fine content exceeds 40%, which is similar to the test results in Section 3.1. e calculation formula for FC th (the threshold of FC) used to calculate the FC th of iron tailings was proposed by Rahman et al [28]. e FC th of iron tailings is approximately 40% [21]. erefore, the iron tailings could be classified into two categories according to the FC th .…”

“…erefore, n should give place to n silt . d 10 is used to calculate the average pore diameter of silt [21]. e permeability of the second iron tailings (2-4) could be calculated by equation (22), and more accurate results were obtained and are shown in Table 1:…”