:: Innovation and Results earn Gekko Another Industry Award

The Australian Mining Prospect Awards aim to recognise and reward companies within the Australian mining industry that have demonstrated innovation and excellence in outcome in a range of categories. Gekko Systems PTY LTD (Gekko) won the Highly Commended Award in the Minerals Processing Plant of the Year category sponsored by ABB Australia at the third annual awards held in Brisbane, Australia, in 2006.

Gekko, an Australian-based mineral processing technology company, was engaged by Ballarat Goldfields NL (BGF) during 2005 to conduct the required test work program and to design, construct, commission and operate a processing plant.

With a very tight design period Gekko successfully incorporated all requirements of the BGF brief for the least possible cost using an innovative solution. Members of the Gekko team are proud of the outcome. "For capital costs of around AUD$20million the plant can recover up to 90% of the gold at 600 000tpa and is easily expandable well beyond that," reports Technical Director at Gekko, Sandy Gray. "The plant is performing above that of our test work predictions. The final tailings residues to date have been better than expected and well below design," adds Mr. Gray. The plant is custom-made and matched to the specific ore body. The majority of the gold can be recovered at a very coarse grind size so we have built an innovative plant that matches the properties of the ore with the properties of the equipment to meet the needs of the customer.

BGF Mill Superintendent, Steve Gannon, receiving the award for the Mineral Processing Plant of the Year Category

Design incorporates the use of conventional equipment in the first half of the plant together with Gekko core equipment attached to the back end. "Compared to a conventional plant the capital costs are about one third for the same throughput because of both the ore type and the approach Gekko has taken to the engineering and to treating the ore," says Mr Gray.

The unique design of Stage 1 of the BGF plant incorporates a conventional two-stage crushing circuit that is achieving a crush size of <25 mm at a rate of >1.5 million tpa. The final product size reduction is carried out by a Vertical Shaft Impactor (VSI) which is achieving better than design at a P80 crush of 650 µm.

The Gekko Gravity Recovery System runs in closed circuit with the VSI and consists of rougher and scavenger InLine Pressure Jigs (IPJ) followed by a cleaner IPJ that produces a concentrate stream of approximately 4% of the mass (5% design). Mass pull is variable depending on the sulphide loading in the circuit. A Falcon concentrator scavenges the final tail. The plant control includes fully-automated startup and shutdown processes.

The processing plant has the additional advantages of minimal environmental impact with energy consumption minimised (approximately 5 kWh/t) compared to conventional milling circuits (15 to 20 kWh/t). Only a small proportion of the ore (5%) will be exposed to cyanide allowing cyanide destruction to be effectively carried out.

Praising the supply and service provided by Gekko, Richard Laufmann, Managing Director at BGF, says "the skills and facilities available through Gekko Systems are second to none."

Gekko has received an order for BGF Stage 2, which will incorporate Resin and Intensive Leach Circuits. Once installed the BGF processing plant will be a state of the art GFIL circuit (Gravity, Float, Intensive, Leach).