ENK successfully produces first nickel from Acoje pilot plant in Philippines
London-listed ENK has announced the first nickel production from its Acoje pilot plant located 250 km north of Manila in the Philippines. Approximately 50 kg (dry weight) of nickel hydroxide product (NHP) was released from the filter press on October 25. Although final assay results are outstanding, initial assays of the NHP at bench top level have contained approximately 49% nickel and 4% iron. The plant can produce approximately 200 kg of NHP per month by utilising ion exchange for Ni-Co separation and purification to process pregnant leach solution from the heap leach trial pad followed by precipitation of the Ni as NHP.
The initial NHP will be sent to potential off-takers for evaluation. Future production from the pilot plant will include a trace iron NHP and approximately a 50% cobalt carbonate product. NHP has wider market appeal than the MHP (mixed hydroxide product) previously produced at the company’s Caldag project in Turkey, due to significantly lower metal impurities. ENK said that the Acoje bankable feasibility study for an atmospheric nickel leaching project remains on track to be completed in the second quarter of 2012. The infill drilling program at Acoje was completed on October 21 and a new updated resource estimate for this tenement is set to be announced in due course once all pending drill assays are returned and the resource estimate is completed by Snowden Mining Consultants. The drill rigs are now in the process of relocating to the Zambales chromite tenement 5 km north of Acoje to complete a 255 hole (3,000 m) program. This program is estimated to be completed early in 2012.
Test work also continues on Atmospheric Pressure Tank Leach (ATL) upstream processing in China with encouraging results to date. ATL is an alternative leaching process to heap leaching. The ATL test work will be completed by late November 2011. A decision on which leaching process will be taken forward to the BFS will be made at that time. Speaking at the pilot plant ENK Managing Director, Robert Gregory commented: “It is a magnificent effort by the Acoje team to go from being on care and maintenance last year to building and commissioning the pilot plant ten months later.”