Tag Archives: Knelson

Knelson concentrator, Gekko ILR set to boost gravity gold recovery at Asante’s Bibiani

Comminution of minerals, Mineral processing, Mineral project development, Mining equipment, Mining services, Precious metals, , , , , , , , ,

Asante Gold’s plan to bring the Bibiani mine in Ghana into production in the September quarter of 2022 remain on track after mobilising a contractor to refurbish the process plant and made plans to upgrade its gravity gold recovery equipment.

The company acquired the mine earlier this year from Resolute Mining, embarking on a journey to return the former operating mine to its past glories.

In a market update, Asante said all activities for the restart were on track.

“Asante is preparing a plan to deliver a mine that can produce approximately 190,000 oz of gold at Bibiani in its first 12 months of operation and circa 240,000 oz every year thereafter for a minimum of six years,” it said.

Tenders have been invited for the selection of a mining contractor, with mobilisation of said contractor expected to proceed in the March quarter of 2022.

At the same time, the process plant refurbishment is slightly ahead of schedule and on budget, the company said.

Harlequin International has been contracted to complete the refurbishment engineering procurement and construction management (EPCM) and has mobilised as scheduled. The full EPCM team, plus requisite complement of tradespeople, is on site to provide training, safety and project delivery systems and resources needed to ensure achievement of a safe and productive work environment, the company said.

Asante explained: “All work activities are proceeding as planned. Principal equipment motors and drives have been taken off site, to be serviced as needed. Electrical components, instrumentation and control systems have been tested and are being upgraded as needed to provide improved performance, above the original design.”

The company said gravity recovery equipment was being upgraded to “2020 level” of competence and automation. This includes the purchase of a new high efficiency “6G Knelson concentrator” (from FLSmidth) and Gekko ILR (InLine Leach Reactor).

Sub-contractors have been engaged to proceed with sand blasting, metal and pipework repair, painting, installation of liners and belts, and to ensure safe and efficient operation, Asante said.

“Equipment that is on site but that was not fully installed by the former owners is in the process of being made ready for operation,” the company added. “As of the last week of October, there are more than 200 workers on site. To date the project remains on budget.”

In July 2018, Resolute Mining, based on some 50,500 m of drilling, released an updated feasibility study for Bibiani reporting JORC compliant resources of 21.7 Mt at 3.6 g/t for 2.5 Moz of gold.

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.”