Bafokeng Rasimone Platinum Mine - Styledrift | platinum mine/processing

 mine, platinum mine/processing

This the is Mining Right for the Styledrift portion of the Bafokeng Rasimone Platinum mine. Original ownership was Royal Bafokeng Holdings with 50% and Anglo American Platinum with 50% through the BRPM Joint Venture which was established in January 2002. The joint venture was restructured in 2010 which resulted in the formation of RBPlat which has 100% control of the mine and is 100% owned by the Royal Bafokeng Nation.

The project is located on the western limb of the Bushveld Ingeous Complex (BIC). The BIC was intruded about 2,060 million years ago into rocks of the Transvaal Supergroup along an unconformity between the Magaliesberg quartzites (Pretoria Group) and the overlying Rooiberg felsites (a dominantly felsic volcanic precursor). The BIC is one the largest mafic/ultramafic layered intrusions in the world, covering an extent exceeding 66,000km2 and a maximum thickness of 8km. It compromises the largest known Platinum Group Metals resource in the world. The mafic component of the BIC hosts layers rich in PGE’s, nickel, copper, chromium and vanadium

In 1970 three exploration holes were drilled by Johannesburg Consolidate Investments Co. Ltd (JCI). After a 20-year inactive period drilling continued from 1990 to 2001, during which time 48 boreholes were drilled. In 1980 JCI undertook additional exploration campaigns at Styldrift and intersected UG2 for the first time. Drilling campaigns started on Frischgewaagd in 1970 and between 1992 and 1998, nine boreholes were drilled on the property. Between 2005 and 2008, a total of 111 boreholes were drilled on Styldrift. During this period pre-feasibility studies were undertaken on both Frischgewaagd and Styldrift.

Construction of the project began in the late 2008 and when completed would double the Bafokeng Rasimone platinum mine’s current production profile from 220 000 oz/y to 450 000 oz/y. With an estimated reserve of 68-million tons, the project was anticipated to yield about 5,4-million ounces over its 27-year life-of-mine.

Access to the underground workings will be via a twin, concrete-lined vertical shaft system comprising a 10.5m-diameter Main shaft and a 6.5m-diameter Services shaft, blind sunk to a depth of 740m and 700m respectively. Footwall infrastructure, mainly for the transporting of ore to the shaft, will be developed approximately 25m below the Merensky reef horizon. Two 22-tonne rock skips will be used to hoist the ore to the surface via the Main shaft. A second footwall network will be developed at 690m, at the base of the UG2 horizon, for potential concurrent exploitation of the UG2 reef.

The shaft infrastructure comprises a main shaft with a diameter of 10.5m sunk to a depth of 740m and a services shaft with a diameter of 6.5m sunk to a depth of 700m below surface The configuration of the Main shaft allows for the following:

-a single deck personnel and material cage compartment with capacity up to 185 people
-a cage counterweight compartment
-two Merensky reef skip compartments designed to accommodate 22-a tonne skips
-two future UG2 skip compartments to accommodate 13-tonne skips

The Services shaft will comprise a personnel and equipment cage compartment with capacity u[ tp 40 people, as well as a cage counterweight compartment. Four winders will be used during the project construction phase and three during the production phase. The height of the Main shaft headgear will be 58.6m and the Service shaft 41.3m. The shaft system will be linked to the up-dip and down-dip on-reef roadway clusters on both the reef horizon and the footwall level. A network of on-strike haulages will underlie all sections for the transportation of ore to the Main shaft.

The orebody lends itself to a combination of mechanised Room & Pillar and conventional breast stoping. The mechanised mining method uses a two stage bord and pillar method (primary and secondary extraction phases). Each trackless mining section will consist of 9 panels and 8 pillars and the primary extraction layout will be 13m wide rooms separated by pillars which are 12m wide and 12m in length. Ventilation holings are mined between panels within the mining sections and are 6.5 metres wide. Regional (17 metres wide) pillars will separate the mining sections. On reaching the stope limit, partial secondary pillar extraction will be undertaken using remote controlled equipment resulting in 12m by 4m crush pillars being left in secondary mining areas. The secondary crush pillars are designed to fall within the width/height ratio of 1.8:1 and 2.5:1. In the very thick reef areas, where reef thickness reaches 3.2 m these secondary crush pillars will be increased to 12m by 6m. Production ramp-up is expected to begin in February 2015 and steady state reached in 2017.

The Merensky footwall is the main artery of the proposed mine and is situated 25m below the Merensky reef horizon. Apart from travel ways, all footwall frastructure will be mechanically developed. This infrastructure includes tipping points on the reef horizon, from which ore will be sent via boxholes to the trucking haulage points 25m below. Fifty-tonne diesel-powered trucks will then transport the ore to ore passes feeding an underlying conveyor belt system 18m below. The conveyor system will include the main conveyor belt decline and an adjacent auxiliary decline.