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The El Teniente case: when recycling entered the mine

📅 July 15, 2026 🏷️ Success story · Mining ⏱️ 5 min read

Circular economy often stays in the speech. This case is the opposite: an input produced from discarded phone batteries operating inside the world's largest underground mine.

The plant's problem

The Hydrometallurgy Plant at Codelco's El Teniente Division uses cobalt sulfate as an additive to produce copper cathodes. Historically it bought it solid and imported: expensive, with stock-outs, and requiring prior dissolution that complicated the operation (three additions per day).

The trial

Since November 2023, the plant has used our recycled cobalt sulfate, delivered in liquid form. The results, published by the regional press in July 2024, speak for themselves:

  • 22% cheaper than the imported product.
  • 40% lower consumption of the additive (higher efficiency).
  • A single daily addition instead of three: standardized dosing.
  • No more prior dissolution and no more stock problems.
"The liquid performed better, the effect is much faster and it is cheaper." — Patricio Navarro, Shift Supervisor, El Teniente Hydrometallurgy Plant.
1,000-litre IBC containers with liquid cobalt sulfate ready for dispatch
Real dispatch: 1,000 L IBCs of recycled cobalt sulfate heading to site.

Why it matters

First, it validates quality: if an input works in Codelco's production process, it works. Second, it validates the recycling business model in Chile: the recovered mineral is not exported as waste, it is sold as a local input with advantages in cost, performance and footprint. Third, it closes the loop almost poetically: the cobalt that left mining returns to mining — this time from your old phone.

📰 The full story was published by El Rancagüino (Spanish). And the process that makes it possible is documented on video on our experience page.
Codelco Cobalt sulfate Circular economy