The effects of hardpan layers on the water chemistry from the leaching of pyrrhotite-rich tailings material |
| |
Authors: | Email author" target="_blank">S?E?GilbertEmail author D?R?Cooke P?Hollings |
| |
Institution: | (1) Centre for Ore Deposit Research, University of Tasmania, Private Bag 79, Hobart, 7001, Tasmania, Australia;(2) Department of Geology, Lakehead University, 955 Oliver Rd, Thunder Bay, Ontario, P7B 5E1, Canada |
| |
Abstract: | Column leaching experiments were used to determine the effects of an iron-rich hardpan layer, on the rate of tailings oxidation and the composition of leachate waters, from the Renison Bell tailings dams in western Tasmania, Australia. One-meter-long PVC columns, filled with tailings, cover material (Cassiterite Flotation Tailings) and hardpan samples from the tailings dams, were leached over a period of 14 weeks. Under dry cover conditions, when hardpan was present, the solute loads peaked at 21–49 days (Fe at 2,294 ppm and SO 4 2- at 4,700 ppm), and stabilised at much lower concentrations after 9 weeks. In contrast, the solute loads steadily increased over time in the column where hardpan was absent (SO 4 2- from 1,800 to 3,100 ppm, and Fe from 407 to 1,692 ppm). Under saturated cover conditions, the solute concentrations in the leachate also increased with time (SO 4 2-from 1,900 to 17,000 ppm, and Fe from 480 to 8,500 ppm). The presence of a hardpan layer between the reactive tailings and cover material has been found to improve leachate water chemistry and lessen the rate of sulphide oxidation. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|