Abstract
The heterogeneous distribution of physical and geoc hemical characteristics of waste rock has a major i nfluence on the acid generating potential of the rock. This includes controlling the rate and extent of water, gas and thermal transport processes, which affect the rate of oxidation and leaching of oxidation products. T wo experimental waste rock piles at the Diavik Diamond Mine have been characterized in terms of particle size ranging from boulders to fines, sulfur content of t he bulk rock and individual size fractions of the r ock, and the acid generating potential of the rock. The developm ent of a digital image processing (DIP) technique p rovides a means of characterizing spatial distribution of the > 10 cm to boulder size fraction of waste rock. Co mbining the DIP techniques with traditional sieve analysis of t he fine fraction provides a full-spectrum grain-siz e distribution of the waste rock. The average sulfur content of th e two waste rock piles was determined to be 0.035 w t. % S (Type I pile) and 0.053 wt. % S (Type III pile), a nd both rock types are determined to be potentially acid generating using standard acid-base accounting meth ods. Detailed analysis of the fine fractions for bo th rock types suggests that the acid generating potential o f the waste rock is not evenly distributed among pa rticle sizes. Although both sulfur content and neutralization pot ential increase with decreasing particle size, over all acid generating potential also increases with decreasing particle size. This research provides a greater u nderstanding of the spatial distribution of rock characteristics that control the generation of acidic leachate in waste rock piles.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call