AngloGold Obuasi to Commission Fourth Gekko Leach Reactor

AngloGold Ashanti’s Obuasi Gold Mine in Ghana will commission a fourth Gekko Systems InLine Leach Reactor (ILR) at its processing plant in 2027, extending a technology relationship that has run without interruption since the mid-2000s. The decision matters beyond one mine: it is a repeat order on the same equipment platform after roughly two decades of continuous service, which says more about the platform than any product brochure could.

The Obuasi plant, which incorporates a BIOX® circuit, has operated three ILRs since the mid-2000s, a record Gekko points to as evidence of sustained trust in the technology’s performance and reliability. The ILR uses a “rolling barrel” design that agitates and leaches coarse gold concentrates under intensive cyanide and oxygen conditions. It is offered as a fully automated batch model for small-volume gravity concentrates, and as a continuous model for high-throughput gold and complex sulphide concentrates from InLine Pressure Jigs and flotation circuits. Gekko cites consistent free gold recoveries above 98% and leaching of coarse concentrates above 300 micron, with leach solution recycling delivering low energy and operating costs. Chemistry is the constraint that shapes the whole layout at Obuasi: potential cyanide exposure to the flotation and BIOX® circuits is a key sensitivity there, and the ILR’s ability to operate within that constraint is a central part of its case.

A fourth unit of the same platform ordered nearly two decades after the first is among the strongest signals in capital equipment procurement: a total cost of ownership case being proven in production, not in a vendor slide deck. For process-plant buyers comparing intensive leach systems, Obuasi’s repeat purchase points to three practical checks. First, installed-base longevity — ask vendors for references running more than ten years, not only recent startups, and ask what changed in the design along the way. Second, integration risk in chemically sensitive circuits: with BIOX and flotation duty in the train, any cyanide carry-over becomes a process incident, so containment, instrumentation and interlocks deserve line-item scrutiny rather than being folded into a generic mechanical specification. Third, configuration flexibility — batch versus continuous models matter when concentrate volumes shift with the ore body, and a vendor supplying both from one platform reduces retraining and spares duplication. The schedule carries its own lesson: a 2027 commissioning planned roughly a year ahead reflects long-lead fabrication for pressure vessels and agitator internals. Buyers who wait until the full flowsheet is board-approved before approaching vendors usually pay for that delay in delivery slots. For equipment suppliers, Obuasi shows how a well-referenced technology turns a single sale into a franchise; in this segment, references outlast price.