Pilot plant of clean process for recycled nitrogen for precious metal recovery

Lead Proponent

COREM

Project Objectives

The overall objective of the project is to reduce gold producer’s impact on aquatic ecosystems through the development of an NaCN (sodium cyanide) regeneration process which allows for recycling of nitrogen sources formed during cyanide processing (sulfide-cyanide reaction by-products) for dissolution of precious metals.

The three (3) main objectives of the project are as follows:

1. Construct a pilot-scale cyanide regeneration processing plant for dissolution of precious metals
2. Demonstrate the performance of the pilot-scale unit for the dissolution of precious metals through recycling of nitrogen sources, on industrial sites.
3. Evaluate both economic efficiency of the process and the reduced aquatic environment impacts.

Expected Results

This project will develop a gold extraction process that is more environmentally friendly. The new process will encourage new mining projects and promote the economic development in the regions where the mines operate.

Anticipated environmental benefits:

1. Significant reduction to volume of contaminated water stored in tailings ponds and increase of water reuse from the metal processing plant.
2. Reducing the amount of toxic nitrogen compound contaminants in tailings ponds and final effluent through the nitrogen reuse in process.
3. Reduction of environmental risks by reducing the amount of cyanide and sulfur dioxide (SO₂): Significant reduction in the amount of fresh NaCN used (> 80%) in the precious metal leaching circuit and therefore reducing it’s transport. Possible elimination of the detoxification circuit which uses large quantities of SO₂ and the transport of this reagent on the roads.