Tag Archives: gravity concentration

Kaiser Reef brings in Gekko Wolff Batch Centrifugal Concentrator to improve gravity recoveries at gold mine

Environmental, Mine operation news, Mineral processing, Mining project news, , , , ,

Kaiser Reef Limited has commenced installation of a Wolff Batch Centrifugal Concentrator (BCC) gravity circuit and ancillary equipment at the Maldon gold processing plant as part of an upgrade program at its operations in Victoria, Australia.

The Maldon plant is just 3 km from the company’s Union Hill Mine, which produced 2.1 Moz of gold, and has a processing capacity of 250,000 t/y, currently operating at between 20% and 30% of its full capacity.

The Wolff BCC comes with features such as a segmented bowl and a rotary union tailored for dirty water applications. These advancements minimise maintenance needs (eliminating the need for cranes during bowl changes) and reduce the demand for clean water, thereby reducing both capital and operational costs, according to manufacturer Gekko Systems.

The gold gravity circuit at Maldon will collect the unusually high concentration of coarse gold observed from the company’s A1 goldmine after the SAG mill. This will enhance recovery by collecting coarse gold separately and earlier from the leach feed than through the current mill flowsheet, the company says.

Kaiser has previously seen gold “held up” withing the processing plant because of gold’s very soft and malleable nature and high density. This has required regular mill liner removal to collect the entrained gold. The company expects this initiative to help enhance and smooth cash flow and also improve overall gold recovery. This equipment is currently being installed and should be operational by early August.

In addition, Kaiser has purchased a previously used Terex cone crushing unit to reduce the size of the crushed ore product from the jaw crusher prior to feeding ore into the SAG mill. The cone crusher further reduces the average rock size delivered by the Terex crusher currently in operation from 75 mm down to below 25 mm.

“Reducing the rock size reduces the time required to grind ore in the ball mill and thereby reduces the company’s energy and power costs,” Kaiser Reef says. “This will increase the effective treatment capacity rate, leading to greater operational efficiency and reduced processing costs. The calculated payback period is approximately eight months.”

These upgrades to the fully permitted Maldon processing plant advance the company’s strategy to significantly ramp up production and cashflow from its Victorian gold projects, particularly the high-grade A1 Gold Mine, Kaiser Reef says.

FLSmidth takes gravity separation to a new level with Knelson GX Concentrating Cone

Comminution of minerals, Mineral processing, Mining equipment, Precious metals, Water management, , , , , , ,

The latest innovation in semi-continuous gravity separation from FLSmidth is delivering a key breakthrough in performance that increases recovery and cuts maintenance downtime, according to the OEM.

For decades, Knelson gravity concentrators have been recognised for their recoveries of gold and precious metals, but the development of the new Knelson GX Concentrating Cone is set to take this performance a step further.

The new patented GX Cone delivers impressive recovery enhancements due to enhanced water distribution within each ring, according to the company.

FLSmidth explains: “As water enters from the base, it flows through zone separator nozzles for a customisable fluidisation profile. This allows for even distribution of water in each ring; the new design also significantly increases the active recovery surface area. The result is a step change in overall coarse and fine gold recovery.”

Test data shows that gold recovery in all size fractions, from course to fine, improved significantly with the GX Cone, according to the company.

By incorporating an advanced distribution of fluidisation water across the entire concentrating cone, the Knelson GX facilitates the highest possible recovery of coarse and fine gold. At the same time, balanced water distribution across the concentrating cone allows for a significant reduction in fluidisation water requirements while improving recovery.

The third major benefit of the Knelson GX is easier maintenance. Because it is made of a customised, abrasion-resistant and durable polyurethane compound, maintenance frequency and operational costs are significantly reduced, FLSmidth says.

Mike Lefler, Head of Global Product Line Manager for Precious Metal Recovery at FLSmidth, said: “The new Knelson GX Concentrating Cone is the culmination of over 40 years of research and operational experience and is exciting news for our customers. It delivers a win-win-win scenario: better recovery, less water use and less downtime due to easier maintenance.

“In short, it helps customers produce more with less resources – a central tenet of our MissionZero ambition to cut water and energy waste in mining by 2030.”

Classic Minerals enlists Gekko gravity unit for processing Kat Gap gold

Mineral processing, Mineral project development, Mining equipment, Mining services, Precious metals, , , , , ,

Western Australia-focused gold exploration and development company Classic Minerals says it has secured a Gekko gold gravity processing plant to be used for future on-site processing of gold ore at its Kat Gap gold project.

Kat Gap, around 120 km southeast of Southern Cross, Western Australia, has an existing 93,000 oz JORC resource with strong exploration upside and scope for high grade open-pit mining, the company says.

Gekko is a leader in the manufacture of gold processing plant and machinery with its plants boasting small footprints and low environmental impact.

An added attraction to Classic is that the Australia-made Gekko plant is modular and mounted on containerised elements providing for scalability and ease of modification, it said. The plant has a 30 t/h capacity and is scalable to a Gekko Python plant (pictured) with a processing capacity of 250 t/h, Classic added.

“Also, the mobility associated with the modular construction enables Classic to locate the plant adjacent to the orebody, which further minimises cartage and processing costs,” it said.

Classic’s purchase is for a two-stage gravity concentration plant from Gekko, which will be provided fully refurbished to new condition. The two-part plant will form the basis of the processing facility to be set up and operated by Classic at Kat Gap.

The company said: “Classic is now on track to set-up, commission and test the Gekko plant and commence processing of the gold rich ore at Kat Gap. The Gekko plant is ideally suited to processing Kat Gap ore, which has a unique high gravity gold concentration. Classic will have the capability and capacity to commence production as soon as the mining approvals (MLA 74/249) have been granted.”

To provide an immediate revenue stream, Classic has also commenced negotiations to toll treat any initial parcels of ore from Kat Gap, while the full-scale plant is configured to suit Kat Gap ore, it added.