Determining whether or not a gold gravity circuit should be installed in a gold plant requires a prediction of how much gold will be recovered. This has always been a difficult task because recovery takes place from the grinding circulating load, in which gold's behavior must be described. / A population-balance model (PBM) to predict gold gravity recovery was developed at McGill University in 1994 (Laplante et al, 1995). The objective of this research was to make this PBM user friendly. This was achieved in two different ways. First, the behavior of gravity recoverable gold (GRG) in secondary ball mills and hydrocyclones was described by two parameters, tau and R-25mum, and these parameters were linked to the circulating load of ore and the fineness of the grinding circuit product, for easy estimation. Second, the database of simulations produced by the PBM was represented by two multilinear regressions (one for coarse GRG, the other for fine GRG) linking the predicted GRG recovery to the natural logarithm of tau, R-25mum , the size distribution of the GRG and the recovery effort (Re ), defined as the proportion, in %, of the GRG in the circulating load recovered by gravity. Re was found to be the most significant parameter, tau the least. The GRG size distribution, represented either by two (coarse GRG) or three (fine GRG) points on the cumulative passing curve, has a significant impact on recovery. A total of twenty different GRG size distributions were used to generate the simulation database. / The multilinear regressions were tested on four case studies, and found to predict GRG recovery well within the precision with which the GRG content can be measured, a relative 5%. Whenever size-by-size recovery data are available, the PBM itself would be used; if not, the simpler regressions would be preferred.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.34000 |
| Date | January 2002 |
| Creators | Xiao, Zhixian, 1970- |
| Contributors | Laplante, A. R. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Engineering (Department of Mining, Metals and Materials Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001873474, proquestno: MQ79103, Theses scanned by UMI/ProQuest. |
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