EnviroMetal achieves high gold recoveries on Albion pretreated refractory gold concentrates
EnviroMetal Technologies Inc. [ETI-CSE; EVLLF-OTCQX; 7N2-FSE] reported results from tests conducted using EnviroMetal’s proprietary and environmentally friendly gold recovery technology to recover gold from concentrates which had been pretreated using the Albion Process™ (supplied by Glencore Technology). The EnviroMetal lixiviant and process recovered an estimated 96.7% of the gold contained in the pretreated concentrate in 24 hours. All tests were performed by EnviroMetal at its lab in Burnaby, British Columbia.
Tests were performed using the EnviroMetal lixiviant in 3 different concentrations to determine leach efficiency, as measured by time to recover the contained gold, and leach recoveries. The sample gold concentrate was pretreated using the Albion Process™ at SGS’s Lakefield division (a Certified Albion Process™ laboratory) with an assayed grade of 39.4 g/t gold.
All tests were conducted using 20% pulp density. The initial test, using regular strength reagent as a baseline, resulted in 96.7% gold recovery in in 24 hours and demonstrated fast leach kinetics with over 89% of the gold recovered in 3 hours. Subsequent tests were done using lower reagent strengths and shorter leach times. The tails from all tests were sent to an external lab to obtain certified gold grades by fire assays. The results of the tests are presented in Table 1.
The takeaways from the tests performed using the EnviroMetal lixiviant are: fast kinetics, with leaching essentially completed in 5.25 hours; reducing reagent strength only moderately lowered overall gold recoveries; and leaching for longer periods may improve gold recovery when using lower reagent strength.
Duane Nelson, EnviroMetal CEO, comments, “The high recovery results on the material pretreated with the AlbionProcess™ could lead to the application of our technology for the treatment of refractory gold ores. Glencore Technologies is the global leader in oxidative atmospheric leaching technologies and our eco-friendly reagent has the potential to add significant value. This combination or fusion of technologies has the potential to emerge as an eco-friendly and cost-effective alternative for the treatment of difficult-to-process refractory gold concentrates.”
EnviroMetal Technologies is engaged in the development and commercialization of environmentally friendly formulas and technologies for the treatment of materials in the primary and secondary metals industries. Using its proprietary non-cyanide, water-based, neutral pH treatment process, EnviroMetal extracts precious metals from ores, concentrates, and electronic waste (E-Waste). EnviroMetal’s technology is emerging as a potential new eco-friendly standard for the hydrometallurgical extraction of precious metals.