Humidity cell tests for the prediction of acid rock drainage

Abstract

This paper presents a study of various geochemical humidity-style weathering tests that were carried out on waste mine rock from Avoca, County Wicklow, Ireland. The aim of this paper is to present data that demonstrate some of the geochemical controls on weathering rates together with release rates from laboratory testwork. These data are used to determine the applicability of various interpretations of humidity cell data for prediction of acid rock drainage. Furthermore, within this context the paper offers opinion on common questions related to the use of such tests: should humidity cells be aerated? How long should the test be run for? Is pre-treatment of the samples required? Is inoculation of the samples with iron and sulfur oxidising microbes required? And should these tests really be considered to be accelerated weathering tests?

Diavik Waste Rock Project: Evolution of Mineral Weathering, Element Release, and Acid Generation and Neutralization during a Five-Year Humidity Cell Experiment

“…A weathering or release rate is the rate at which primary minerals are transformed to secondary minerals or dissolved reaction products, congruently or incongruently, with release of elements [7]. Predicting field conditions from humidity-cell results can be difficult because of coupled and sustained biogeochemical processes in the field that create a more complex environment than can be reproduced in the laboratory [2,[8][9][10][11].…”

Revue de littérature détaillée sur les tests statiques et les essais cinétiques comme outils de prédiction du drainage minier acide

“…Il existe plusieurs types d'essais cinétiques selon le dispositif expérimental utilisé tel que synthétisés aux Tableaux 4 et 5, à savoir : les colonnes (au laboratoire ou in situ), les minicellules d'altération, les cellules humides, et les parcelles de terrains. Les tests en colonne, cellules humides et parcelles de terrain sont les plus utilisés pour la prédiction du DMA (Benzaazoua et al 2001Bowell et al 2006;Demers et al 2008;Frostad et al 2002;MEND 2009;Price 1997;Plante 2012;Sapsford et al 2009;Villeneuve 2004, Villeneuve et al 2009). Testing and Materials, ASTM D 5744-96, 1998;2007), est l'essai cinétique le plus utilisé dans l'industrie minière.…”

Investigation of the Oxidation Rate of Sediments from AMD Using Humidity Cell Test

“…Among others, the potential of contaminants dispersion from the AMD and the persistence of pollution may depend on the property of the immersed soils; it is therefore important to better understand the impact of the geochemical properties of the soil on the mobility/generation and/or mitigation of pollution along the Elvis Fosso-Kankeu is with the School of Chemical and Minerals Engineering of the North West University, Bult area-Potchefstroom-South Africa basin. Humidity cell test is a widely used method to predict the oxidation of rocks and their capacity to generate acid over time [3]. According to Price [4], kinetic testing may provide prediction information such as: -Rates of acid generation and neutralization, -The expected time of possible AMD formation, necessary for planning prevention intervention, and -Possible spreading of contaminants in the AMD based on the geochemistry conditions.…”