Goro Process

This separation principle has been applied commercially at Falconbridge Nik-kelverk in Norway (Wigstol and Froyland 1972), at Sumitomo Metal Mining Co. in Japan (Suetsuna et al. 1980), and at the Societe de Nickel refinery in France (Bozec et al. 1974). More recently, this chemistry has been included in the flow sheet for the processing of a nickel laterite in the Goro process in New Caledonia (Mihaylov et al. 2000) (see Section 5.3.3.2). 

The Goro process (Figure 5.14) developed by INCO (now CVRD-lnco) for the treatment of a nickel laterite deposit in New Caledonia (Bacon and Mihaylov 2002 Mihaylov et al. 2000 Mihaylov et al. 1995) also treats the laterite leach liquor directly but uses a completely different approach. The flow sheet involves the coextraction of nickel and cobalt by SX with the sulfnr-snbstitnted organophosphinic acid, CYANEX 301, followed by their separation in chloride medinm by SX using an amine extract. 

FIGURE 5.14 Goro process for recovery of nickel from laterites. (Adapted from Mihaylov, I. et al. 2000. CIM Bull. 93 124-130. With permission.)... 

Mihaylov, I. Krause, E. Colton, D. F. Okita, Y. Duterque, J. P. Perraud, J. L. The development of a novel hydrometallurgical process for nickel and cobalt recovery from Goro laterite ore. CIM Bull. 2000, 93, 124-130. 

W.G. Bacon, D. F. Colton, E. Krause, 1.0. Mihaylov, A. Singhal, A. Vahed, J.P. Duterque, Development of the Goro Nickel Process, ALTA 2005 Nickel/Cobalt Conference, ALTA Metallurgical Services, Melbourne, Australia, 2005, 20pp... 

Y. Okita, A. Singhal, J-J. Perraud, Iron Control in the Goro Nickel Process, Iron Control Technologies, J.E. Dutrizac, P.E. Riveros, Eds., CIM, Montreal, Quebec, Canada, 2006, 635-651. 

In a similar vein, the Ambatovy nickel project in Madagascar will use HPAL to process a limonite ore. The capital cost (m w.sherritt.com) is now reported to be of the order of 5.5 Billion for an annual production of 60,000 tonnes of nickel per annum. This is of the same order of magnitude as the Goro facility. 

Two planned nickel production facilities, both located on the Pacific island of New Caledonia, will serve to convey a sense of tiie scale of operations. The Goro facility, which processes the nickel oxide ore laterite, is scheduled to produce 6 tons of nickel per hour by the year 2008. The corresponding amount of sludge to be washed in the coxmtercurrent cascade has been eshmated at 5000 tons/h. Evidently this calls for tiie use of sizable tanks, and the available information indicates that a diameter of 70 m is to be used. The scale of operations at the second planned site, Koniambo, is similar, but the ore here is a sulfide that is processed by roasting. 

The base case for our calculations will be the slurry that results from the acid leach of nickel ores addressed in Illustration 7.8. After depressurization, the slurry exiting the leach reactor stabilizes at a temperature of 90°C and a sulfuric acid concentration of 5% by weight. It now has to be cooled to a level acceptable for further processing, say 30°C. The tonnage rate is set at 1 ton/s, which corresponds roughly to e projected output of the Goro facility. These are the parameters to be used here. 

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