Modern Mining July 2018

COAL

stonework sections (with maintenance facilities for four stonework sections). Coal will be mined from the 4-m thick Number 4 seam at between 140 m and 160 m below surface by normal bord-and-pillar meth- ods as employed at Middelbult. Continuous miners break the coal and load into shuttle cars, which deliver into feeder breakers; an

which resulted in a more cost effective and safer methodology. Weighing 291 tonnes, the winder house was moved horizontally over a distance of 58 m and lifted 30 m high. Large steel structures for the material han- dling system were assembled in modules on surface and were then lifted into position, reduc- ing the exposure of people working at heights. The mine is served by a 150-m deep, 11,7-m diameter man/material shaft with a 65-ton payload capacity (and the ability to accommodate 200 people); a 120-m deep, 9-m diameter ventilation shaft (which can extract 1 050 m 3 /s using three 750‑kW fans); and a 6 m x 3 m x 980 m long incline shaft which houses a 3,5 m/s incline con- veyor which can extract 3 200 tons of coal per hour. Early development work on the incline shaft was complicated by weathered dolerite near surface and a high water table, requiring extensive cementation of the porous areas. During construction of the mine more than 2,9 million cubic metres of earth were moved, 2 000 tons of steel- work fabricated and erected, over 50 000 cubic metres of concrete placed and over 70 km of electrical cabling purchased. The workforce on site numbered 2 409 at the height of construction and the project was completed with a Lost Work Day Case Rate of zero and a Recordable Case Rate of 0,53. The capacity of Shondoni is 9,2 Mt/a expandable to 10,5 Mt/a. It will have six production sections (with mainte- nance facilities for ten sections) and two

The 15 000 ton surface coal bunker is a combination of in-situ construction and precast panels. The winder house was constructed on surface and lifted with one lift into position.

July 2018  MODERN MINING  23