Modern Mining June 2017

MINING News

HOISTING SOLUTIONS Winder Controls is a leader in the mechanical, electrical and hydraulic design, manufacture and installa- tion of mine winders and related equipment. Our designs comply with the latest international safety and reliability standards including SIL assessments where applicable. Our services include relocations, refur- bishment and upgrades, as well as full aftersales and maintenance support. In addition we offer a range of special products including steel wire rope handling equipment, Three Chamber Energy recovery systems and Nuclear Waste Disposal Technology.

CIL tank construction at Yanfolila earlier this year (photo: Hummingbird).

west Mali close to the border with Guinea, Yanfolila was acquired by Hummingbird from Gold Fields in 2014 in a deal worth US$20 million (with Gold Fields accept- ing payment in Hummingbird shares). Gold Fields was planning a 3 Mt/a opera- tion at Yanfolila. Hummingbird has scaled this back considerably to 1,24 Mt/a, in the process bringing down the capex to a remarkably low US$79 million.  on a co-disposal strategy where the finer tails are deposited with a coarse mining waste product that optimises the waste footprint and environmental impact. A wet tailings facility is not required at the Phase 1 tonnage but feasibility level designs have been completed for a tailings dam, which will be required at higher tonnages. For the 30-year mine life of the proj- ect, the ore mined is expected to yield an average grade of 8,1 % C. The ore will go through a process involving grind- ing, flotation, dewatering, drying and sieving/classification. The process flow sheet has been designed for the stan- dard purity of 96 % C for all flake sizes, and will be capable of reaching purities in excess of 98 % C (as demonstrated in the 2015 Molo FS technical report). The final products will be bagged and shipped in containers to various markets via the ocean shipping port of Fort Dauphin. 

eight years of 107 000 ounces although the first full year of operation will see 132 000 ounces being produced. In all, some 8,7 Mt of ore (at an average grade of 2,95 g/t and a LOM strip ratio of 11,9 to 1) will be mined over the mine life to pro- duce a total of 770 000 ounces. According to Hummingbird, there are over 1 Moz of gold outside the current mine plan. Located in the Sikasso region of south- pit, fully-modularised mining operation using a 100 % owner-operated fleet that will process an average of 240 000 tonnes of ore per year of mill feed that will be processed on site. The processing plant will produce an average of 17 000 tonnes per year of finished SuperFlake™ concentrate. The Phase 1 modular mine will uti- lise two 1,4 MW diesel generators, with one running and one on standby. Water will be supplied from a well field that has been defined by drilling and geo- hydrological modelling. The processing plant will consist of conventional crush- ing, milling and flotation circuits followed by concentrate filtering, drying and screening. Phase 1 will employ dry-stack tail- ings, which will forfeit the need for a wet tailings facility and is designed to accommodate the run-of-mine tonnage for the 30-year life of mine. This is based

Tel: +27 (0)11 383 9300 www.winder.co.za

Fax: +27 (0)11 383 9305 email: winder@winder.co.za

June 2017  MODERN MINING  7