Hambledon Mining has started production at its Ognevka treatment plant in East Kazakhstan.

After a period of commissioning, the plant began operating on November 26 and, following the resolution of some minor faults, full time treatment of clinker began on November 29. The Ognevka processing plant is designed to produce concentrates containing gold, silver, copper, iron and coke from the re-treatment of zinc smelter residues.

The processing facility is configured to treat up to 350,000 tonnes per year of copper, gold and silver-containing residues (sinter slag or clinker) from the zinc smelters. The initially targeted rate of production will be 240,000 tonnes per year while the optimum operating parameters are assessed.

Initial production will involve the re-treatment of 150,000 tonnes of high grade tailings of previously treated clinker. Thereafter, clinker will be procured from other companies that have large stockpiles, for which they now pay environmental penalties.

At the expected metallurgical recoveries and available prices, the revenue from each tonne of clinker treated, including by-products, is expected to be more than $75. Toll-treatment options are being investigated which are likely to improve this figure to around $125 per tonne, though, the increase would be partly offset by the toll treatment charge.

The flexibility of the plant also allows for the treatment of various other feedstocks, including feldspar tailings (recovery of saleable feldspar, lithium and tantalum concentrates), pegmatite ores (tantalum, tin, mica and feldspar concentrates) or other slag via gravity, magnetic separation or flotation methodologies.

Hambledon chief executive Nick Bridgen says: "The plant and related infrastructure at Ognevka have been stripped down and refurbished from top to bottom in just five months, which is a very creditable achievement by the entirely local management." www.hambledon-mining.com