Cyanide
Our Technologies for Cyanide Recovery & SART Process
Gold recovery can become uneconomical when cyanide-soluble base metals such as copper and zinc are present in gold ore deposits. These metals form weak acid dissociable (WAD) complexes with the cyanide, preferentially competing for the reagent. The result is:
- High fresh cyanide consumption.
- Poor gold doré purity and increased loading on activated carbon.
- High concentrations of copper-cyanide complexes in tailings that require costly cyanide destruction.
THE SART PROCESS
We offer the SART process to remove the metallurgical interference of cyanide-soluble metals and to efficiently achieve cyanide recovery and cyanide recycle in gold processing circuits.
SART process mining (Sulphidization-Acidification-Recycling-Thickening) breaks the base metal bond from the WAD complex and precipitates the metal as a commercial-grade solid concentrate. The cyanide is then regenerated as free cyanide and recycled directly back to the gold extraction circuit.
We have designed and constructed full-scale plants, provided process reviews and commissioning for plants under construction, and carried out extensive flowsheet development and testing programs for SART globally.
CASE STUDIES
With extensive operational experience, we customize SART systems to suit site-specific conditions, ensuring reliable performance and long-term results.
MASTRA MINE
Designed and commissioned a SART plant in a tight nine-month schedule to reduce copper interference, successfully recovering 87% of copper and 80% of cyanide from barren leach solution.
MARICUNGA MINE
Provided process review and commissioning services for a high-capacity (18,000 m³/day) SART plant at an open-pit heap leach operation, successfully achieving up to 94% cyanide recovery and 89% copper recovery.
Frequently Asked Questions About Cyanide Recovery
How does the SART process improve gold mining economics?
By breaking WAD cyanide complexes, the SART process recovers cyanide for recycling and precipitates base metals like copper or zinc as saleable concentrates. This lowers fresh cyanide consumption, reduces the need for expensive cyanide destruction reagents, and generates a new revenue stream from the recovered base metals.
Can SART replace traditional cyanide destruction?
While traditional cyanide destruction methods safely eliminate cyanide from tailings, they do not allow for its reuse. The SART process recovers and recycles the free cyanide back into the leach circuit, significantly lowering operating costs and minimizing the volume of cyanide complexes that must be sent to the detoxification circuit or tailings facility.