Mine excursion
Kongo River, a subsidiary of Teichmann SA, was appointed as the earthworks and civil contractor for the airstrip at Bisie.
Volvo, Scania or MAN,” says Faber. The Atlas Copco LHD is a 10-tonne class loader and the tipper trucks will be equipped with an 18-cm ³ bin. When fully loaded, the truck will carry about 20t of material. The specific gravity of the Bisie ore is 3.5t / m ³, and Faber says the bin sizes on the rock moving equipment had to be reduced to prevent damage to the hydraulic system, suspension and transmission. The trucks will tip the ore on surface stockpiles, from where it will be fed by Bell front-end loaders into the processing plant.
A set of primary, secondary and tertiary crushers will reduce the run of mine ore from 450mm to 80 % passing minus 10mm. The minus 10mm material forms the feed for the jigs. The underflow from the jigs is fed through a series of shaking tables and spirals to create a final concentrate containing about 62 % tin. A flotation step is required to remove the sulphide minerals from the tin concentrate, following which the concentrate is thickened and filtered to reduce its moisture content. Filtration will be carried out on horizontal belt filters, supplied by South African company Roytech.
Shipping out
Once bagged, the tin will have to be trucked to Goma, and this is where the operation becomes tricky. The road to Goma is in a very bad condition, however, Alphamin is assisting the North Kivu Province in upgrading the road over the next six months. The strategy is to have rough terrain 4 x 4 trucks cover the portion of road from the village of Logu to the mine( about 35km), which is extremely rough conditions. At Logu the product is then reloaded onto normal road trucks that will transport it further to Goma, where the customers will take over the logistics, and truck the tin to either Dar es Salaam in Tanzania or to Mombasa in Kenya. TMK, a local DRC transport company, has been contracted to take care of the transport. The company has invested in a fleet of 18 rough terrain trucks which will supplement its current fleet of normal road trucks.
“ Logistics is a significant part of this project, and one the major challenges,” says Faber.
Dealing with the bumpy road
The journey to Walikale and from there to the mine is bumpy, but rewarding. There is no doubt that further challenges await the brave and competent team at Bisie. These will probably never totally disappear. Investing in the DRC is a high-risk strategy, building a mine from scratch in the eastern parts of the DRC, is, well, not for the faint hearted. The major risks, says Robinson, are the infrastructure constraints, political risks, the artisanal question and security.
[ 20 ] MINING MIRROR JANUARY 2018