Engineering & Mining Journal

MAY 2017

Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr

Issue link:

Contents of this Issue


Page 17 of 59

REGIONAL NEWS - LATIN AMERICA 16 E&MJ • MAY 2017 BALL MILLS ROD MILLS AG / SAG MILLS PELLETIZING DISCS MIXING DRUMS MIXERS ROTARY SCRUBBERS ROTARY DRYERS TURN-KEY PROCESSING PLANTS Mining projects from one source CEMTEC Cement & Mining Technology GmbH Ennshafenstraße 40 • 4470 Enns • Austria ( +43/7223/83620-0 • +43/7223/83620-333 - • be stockpiled and processed at the end of the mine life. The mining plan consists of two years of limited pre-stripping prior to ore processing start-up, 10 years of open- pit mining, and two years of low-grade ore stockpile re-handling to feed the mill. Because of significant rainfall, terrain, and saprolite material, a mixed mining equipment fleet is planned. The initial fleet will consist of two 6.7-m 3 -capacity excavators loading a fleet of nine 40-mt articulated dump trucks, which will be used for pioneering excavation and most of the saprolite mining. As the open pit expands, a larger mining fleet will be in- troduced consisting of three 12.0-m 3 -ca- pacity excavators and 17 91-mt rear dump trucks to perform most of the bulk mining production. The Montagne d'Or plant is designed to treat the range of ore types and blends that will be mined over the life of the pro- ject. Unit processes will include primary jaw crushing; single-stage semi-autoge- nous grinding with recycle to produce an 80% passing 75-µ grind size; gravi- ty concentration and removal of coarse gold from the milling circuit recircula- ting load; pre-leach thickening; a leach/ carbon-in-leach circuit incorporating a leach tank and six carbon-in-leach tanks for gold adsorption; an elution circuit treating loaded carbon; electrowinning; and gold smelting to produce doré. Nordgold CEO Nikolai Zelenski com- mented, "The Montagne d'Or is world- class, high-grade orebody, and the work we have now completed shows a project with robust economics. It meets our crite- ria for project development as it benefits from straight-forward metallurgy, excel- lent recovery rates, and a moderate strip- ping ratio. "The mine will be a major employer in the region and generate significant reve- nues for the country when fully operation- al. Montagne d'Or is a core part of our long-term growth pipeline, and we look forward to progressing through the per- mitting process." San Ramon Achieves Commercial Production After completing construction, commis- sioning of the mill and pouring first gold in November, Red Eagle Mining Corp. reported that the San Ramon gold mine achieved commercial production at the end of March. The processing facility has reached a steady state and underground mining is progressing at an increasing rate with the opening up of additional ore development headings. Since Q3 2016 when the decline moved through oxidized material, requir- ing additional support, into competent granodiorite, daily advance rates have substantially increased from 3 m/d up to 27 m/d. The main and secondary ramps have advanced 2.4 km from the portal. A 57-m vertical ventilation shaft has been completed and connected to the under- ground workings. Initial poor ground conditions were encountered. Accordingly, the mining method has been adjusted to convention- al mechanized cut-and-fill stoping, stope lengths have been reduced to 40 m and ground control has improved, minimizing dilution. The 100- and 125-m levels are currently being mined with seven ore de- velopment headings. The processing facility commission- ing is complete and exceeding design

Articles in this issue

Links on this page

Archives of this issue

view archives of Engineering & Mining Journal - MAY 2017