The first nickel has been produced at ENK’s pilot plant on Luzon Island in northern Philippines. About 50kg of nickel hydroxide product (NHP) was released from the filter press, with initial assays showing the product contains about 49% nickel and 4% iron.
The plant is about 250km north of Manila, and can produce about 200 kilograms of NHP per month, using ion exchange to separate and purify the nickel and cobalt. The initial NHP will be sent to potential off-takers for evaluation. It has wide market appeal due to significantly low metal impurities.
ENK managing director Robert Gregory says “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 10 months later.”
ENK has two deposits on Luzon Island, with a combined JORC estimate of 840,000 tonnes. The company hopes to use its low-cost heap leach process to extract nickel laterites at both the Acoje and Zambales chromite deposits.
The company has demonstrated the percolation and extraction of nickel at its large-scale demonstration plant at Çaldag in Turkey with continuous operations over a three year period. At this flagship project, ENK irrigates the heaps with dilute sulphuric acid, producing saleable mixed hydroxide product from the downstream precipitation plant. Recoveries of 72% have been used in the Çaldag bankable feasibility study for both nickel and cobalt. However, this mixed hydroxide product (MHP) has a higher level of metal impurities than the NHP produced from the pilot plant.
Test work on an atmospheric pressure tank leach (ATL) in China is also continuing with encouraging results to date. ATL is an alternative leaching process to heap leaching and the company hopes test work on this system will be completed by late November when a decision will be made on which leaching process will be taken forward to the BFS.
ENK’s infill drilling program at Acoje was completed last month and a new updated resource estimate for this tenement will be announced once all pending drill assays are returned. The drill rigs are being relocated to the Zambales chroite tenement about 5km north of Acoje to complete a 255 hole, 3000 metre program.
The Acoje bankable feasibility study for an atmospheric nickel leaching project remains on track for completion by June 2012.