Documents disponibles écrits par cet auteur

Flotation of mixed copper oxide and sulphide minerals with xanthate and hydroxamate collectors / K. Lee in Minerals engineering, Vol. 22 N° 4 (Mars 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 4 (Mars 2009) . - pp. 395–401 Titre : Flotation of mixed copper oxide and sulphide minerals with xanthate and hydroxamate collectors Type de document : texte imprimé Auteurs : K. Lee, Auteur ; D. Archibald, Auteur ; J. McLean, Auteur Année de publication : 2009 Article en page(s) : pp. 395–401 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Copper  oxide  ores  Copper  sulphide  ores  Flotation  collectors  Mineral  processing  Alkyl  hydroxamates Résumé : Sherwood Copper’s Minto Mine processes a high grade copper–gold deposit in Yukon, Canada. The ore mined is from a primary copper sulphide deposit with separate additional deposits of copper oxides. In conjunction with Ausmelt Chemicals, Minto is currently investigating options to recover copper oxide and sulphide minerals using flotation by blending their primary sulphide ore with oxide ores. The blend used in this laboratory scale investigation was 70% sulphide ore and 30% oxide ore on a weight basis. The copper sulphides present in the blend were bornite and chalcopyrite, while the oxides were malachite and minor azurite. From previous flotation investigations of mixed copper oxide and sulphide minerals using xanthate and hydroxamate collectors it was hard to distinguish the impact of the alkyl hydroxamate collector on sulphide recovery as the sulphide and oxide minerals occurred naturally together. In the case of the Minto operation the copper oxide and sulphide minerals occur in separate ore deposits and can be treated separately or blended together. This investigation has shown that using n-octyl hydroxamates (AM28 made by Ausmelt Limited) in conjunction with traditional sulphide collectors can successfully simultaneously recover copper sulphides and oxides by flotation from blended ore minerals. The copper sulphide recovery did not decrease when processing the blended ore compared to treating the sulphide ore independently. At a blend of 70% sulphide ore and 30% oxide ore, the rougher scavenger copper recovery was as high as 95.5%. The copper recovery from the blended ore using a mixture of collectors was shown to be superior to the recovery obtained using only xanthate after controlled potential sulphidisation. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687508002690 [article] Flotation of mixed copper oxide and sulphide minerals with xanthate and hydroxamate collectors [texte imprimé] / K. Lee, Auteur ; D. Archibald, Auteur ; J. McLean, Auteur . - 2009 . - pp. 395–401. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 4 (Mars 2009) . - pp. 395–401 Mots-clés : Copper  oxide  ores  Copper  sulphide  ores  Flotation  collectors  Mineral  processing  Alkyl  hydroxamates Résumé : Sherwood Copper’s Minto Mine processes a high grade copper–gold deposit in Yukon, Canada. The ore mined is from a primary copper sulphide deposit with separate additional deposits of copper oxides. In conjunction with Ausmelt Chemicals, Minto is currently investigating options to recover copper oxide and sulphide minerals using flotation by blending their primary sulphide ore with oxide ores. The blend used in this laboratory scale investigation was 70% sulphide ore and 30% oxide ore on a weight basis. The copper sulphides present in the blend were bornite and chalcopyrite, while the oxides were malachite and minor azurite. From previous flotation investigations of mixed copper oxide and sulphide minerals using xanthate and hydroxamate collectors it was hard to distinguish the impact of the alkyl hydroxamate collector on sulphide recovery as the sulphide and oxide minerals occurred naturally together. In the case of the Minto operation the copper oxide and sulphide minerals occur in separate ore deposits and can be treated separately or blended together. This investigation has shown that using n-octyl hydroxamates (AM28 made by Ausmelt Limited) in conjunction with traditional sulphide collectors can successfully simultaneously recover copper sulphides and oxides by flotation from blended ore minerals. The copper sulphide recovery did not decrease when processing the blended ore compared to treating the sulphide ore independently. At a blend of 70% sulphide ore and 30% oxide ore, the rougher scavenger copper recovery was as high as 95.5%. The copper recovery from the blended ore using a mixture of collectors was shown to be superior to the recovery obtained using only xanthate after controlled potential sulphidisation. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687508002690

Robust vehicle routing problem with deadlines and travel time/demand uncertainty / C. Lee in Journal of the operational research society (JORS), Vol. 63 N° 9 (Septembre 2012) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 63 N° 9 (Septembre 2012) . - pp. 1294–1306 Titre : Robust vehicle routing problem with deadlines and travel time/demand uncertainty Type de document : texte imprimé Auteurs : C. Lee, Auteur ; K. Lee, Auteur ; S. Park, Auteur Année de publication : 2012 Article en page(s) : pp. 1294–1306 Note générale : Operational research Langues : Anglais (eng) Mots-clés : Vehicle  routing  Robust  optimization  Column  generation Index. décimale : 001.424 Résumé : In this article, we investigate the vehicle routing problem with deadlines, whose goal is to satisfy the requirements of a given number of customers with minimum travel distances while respecting both of the deadlines of the customers and vehicle capacity. It is assumed that the travel time between any two customers and the demands of the customer are uncertain. Two types of uncertainty sets with adjustable parameters are considered for the possible realizations of travel time and demand. The robustness of a solution against the uncertain data can be achieved by making the solution feasible for any travel time and demand defined in the uncertainty sets. We propose a Dantzig-Wolfe decomposition approach, which enables the uncertainty of the data to be encapsulated in the column generation subproblem. A dynamic programming algorithm is proposed to solve the subproblem with data uncertainty. The results of computational experiments involving two well-known test problems show that the robustness of the solution can be greatly improved. Note de contenu : In an earlier version of this article S Park's affiliation was wrongly given as ETRI. The correct affiliation, KAIST, is shown in this final version of the article. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n9/abs/jors2011136a.html [article] Robust vehicle routing problem with deadlines and travel time/demand uncertainty [texte imprimé] / C. Lee, Auteur ; K. Lee, Auteur ; S. Park, Auteur . - 2012 . - pp. 1294–1306. Operational research Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 63 N° 9 (Septembre 2012) . - pp. 1294–1306 Mots-clés : Vehicle  routing  Robust  optimization  Column  generation Index. décimale : 001.424 Résumé : In this article, we investigate the vehicle routing problem with deadlines, whose goal is to satisfy the requirements of a given number of customers with minimum travel distances while respecting both of the deadlines of the customers and vehicle capacity. It is assumed that the travel time between any two customers and the demands of the customer are uncertain. Two types of uncertainty sets with adjustable parameters are considered for the possible realizations of travel time and demand. The robustness of a solution against the uncertain data can be achieved by making the solution feasible for any travel time and demand defined in the uncertainty sets. We propose a Dantzig-Wolfe decomposition approach, which enables the uncertainty of the data to be encapsulated in the column generation subproblem. A dynamic programming algorithm is proposed to solve the subproblem with data uncertainty. The results of computational experiments involving two well-known test problems show that the robustness of the solution can be greatly improved. Note de contenu : In an earlier version of this article S Park's affiliation was wrongly given as ETRI. The correct affiliation, KAIST, is shown in this final version of the article. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n9/abs/jors2011136a.html