Meares Soputan Mining (MSM), one of Indonesia’s leading gold producers, has completed the installation and commissioning of two Aachen reactors at its Toka Tindung processing plant. The installation marks a significant milestone for both MSM and Maelgwyn, the technology provider behind the Aachen system, as the two companies collaborate to enhance gold recovery and processing efficiency at the site.

The reactors, installed in February 2025 and fully commissioned by late March, are designed to increase dissolved oxygen levels in the leaching circuit—an essential factor for effective gold extraction. By improving oxygen transfer, the Aachen technology supports better leaching kinetics, particularly in sulphide-rich ores. Initial performance results are already showing positive trends, with the site team optimistic about ongoing improvements.

The decision to implement the Aachen system followed a detailed onsite test campaign. Over ten individual tests were carried out under real operating conditions, with dissolved oxygen levels consistently exceeding 35 ppm—well above the typical range achievable through traditional oxygen sparging methods. These tests pointed to a potential improvement in gold recovery rates of up to 3%, offering a compelling case for full-scale implementation.

“The testwork showed great promise, and we’re already seeing signs that those gains are being realized,” said Tom Rigby, Maelgwyn Business Development Manager. “The entire site team is excited to watch the technology perform in a live production environment. We’re optimistic that as we fine-tune operations, the benefits will only grow.”

The Aachen reactors were installed in a recirculation loop on the first leach tank, with minimal impact to existing plant infrastructure. While commissioning was delayed slightly due to third-party pump issues, the integration itself was smooth, occurring during a planned shutdown to avoid operational disruptions.

Since commissioning, improvements have already been noted in both oxygenation and flow dynamics within the circuit. While one of the oxygen booster pumps has yet to reach full design pressure—limiting some of the shear effects Aachen is known for—the early results are encouraging. MSM expects further performance improvements as equipment tuning continues and full oxygen supply capacity is restored.

Maelgwyn, the UK-based company behind the Aachen technology, expressed enthusiasm about the partnership with MSM and the promising results from the installation.

“We’re proud to be working with Meares Soputan Mining on this important project,” said Rigby “Their commitment to innovation and operational excellence makes them an ideal partner. We’re looking forward to seeing how the technology continues to deliver value in the months ahead.”

The Aachen system offers a low-capex, high-impact solution for processing operations aiming to increase metal recovery without major overhauls. Its adoption by MSM reflects a broader industry trend toward efficiency-driven innovation in mineral processing.

As MSM and Maelgwyn continue to monitor and optimize the reactors, the mining community will be watching closely. Early signs suggest that this installation could become a model for similar operations across Southeast Asia and beyond