For nearly 30 years, Gekko Systems’ InLine Leach Reactor (ILR) has been one of the most influential technologies in modern gold and silver processing. When it was commercialised in 1997, the ILR became the world’s first intensive leach reactor designed specifically for the secure, efficient treatment of gravity concentrates, a breakthrough that reshaped industry expectations for recovery performance, plant security, and operational efficiency.
As part of Gekko’s 30year milestone series, this article explores the ILR’s origins, evolution, global adoption, and ongoing impact on intensive leaching and gravity gold recovery worldwide.
In the 1990s, most gravity gold plants relied on shaking tables, open, labour intensive systems that exposed operators to security risks and limited metallurgical performance. Gekko identified a critical opportunity: create a sealed, controlled, intensive leaching environment that could deliver higher recoveries while dramatically improving security.
The result was the InLine Leach Reactor, a world–first innovation that introduced:
- a fully enclosed leaching chamber
- faster, more consistent gold dissolution
- improved security by eliminating open concentrate handling
- higher recoveries from gravity concentrates
This shift from open tables to enclosed intensive leaching marked a step change in gold extraction technology and set a new global benchmark for secure, high efficiency processing.
The first ILR units were designed as continuous reactors to treat high volume IPJ concentrates. They quickly demonstrated strong performance, but industry demand soon expanded to include operations with high–grade, low–tonnage concentrates.
Gekko responded by developing the batch ILR, which rapidly became the preferred configuration for gold plants seeking:
- higher security
- improved metallurgical control
- reduced operator exposure
- simplified integration into existing circuits
The batch ILR’s versatility allowed it to treat both coarse and fine concentrates, making it suitable for a wide range of ore types and plant designs.
This adaptability became one of the ILR’s defining advantages, and a key driver of its global adoption.
From early installations in Australia to rapid uptake across Africa, the ILR quickly established itself as the most trusted solution for intensive leaching of gravity concentrates.
Today, more than 200 ILR units operate across major gold producing regions, the largest global installation base for intensive leach reactors.
The ILR’s reputation is built on:
- consistently high gold and silver recoveries
- improved plant security
- predictable, repeatable performance
- reduced operational risk
- Long term durability
A remarkable testament to its engineering integrity: the original R&D prototype, commissioned nearly 30 years ago, still operates at the Henty Gold Mine in Tasmania.
Gekko has continually refined the ILR to meet evolving industry needs, ensuring the technology remains at the forefront of intensive leaching.
Key advancements include:
- Treatment of both coarse and fine concentrates: This flexibility allows operations to optimise recovery across a wider range of gravity circuits.
- Gold and silver recovery capability: The ILR’s chemistry and design support efficient extraction of both precious metals.
- Advanced intensive leach test protocols: Gekko’s proprietary test procedures guide plant design, scaleup, and metallurgical optimisation worldwide.
- The next generation ILR3000: In 2024, Gekko commissioned the ILR3000 batch automatic unit, achieving 98–99% recoveries on startup, a milestone that reflects the strength of the original concept and the continuous innovation behind it.
These advancements ensure the ILR remains a leading solution for operations seeking higher recoveries, improved security, and more efficient gold processing.
The ILR is more than a reactor, it is a technology that embodies Gekko’s philosophy of smarter, more efficient mineral processing.
Its enduring relevance is driven by:
- the global shift toward secure, low risk processing
- the need for higher recovery from gravity circuits
- increasing focus on operational efficiency
- demand for modular, flexible plant design
As gold and silver operations continue to evolve, the ILR remains a trusted, proven solution that delivers measurable value.
As Gekko celebrates 30 years of innovation, the ILR stands as one of our most significant contributions to the mining industry. Its legacy is defined not only by its pioneering origins, but by its ongoing impact on gold recovery, plant security, and intensive leaching performance worldwide.
A pioneering idea in 1997, a global standard today.
Explore more milestones from Gekko’s 30 year journey and discover how our gold processing technologies, including the InLine Leach Reactor, continue to shape the future of smart, efficient mineral processing.
