The use of the WIRTGEN 3000 SM Surface Miner ought to enhance coal quality and the degree of seam exploitation,expecially in area with thin coal and overburden seams. The WIRTGEN 3000 SM Surface Miner was introduced in 1988. The performance of the WIRTGEN 3000 SM Surface Miner was tested in an area of Cardiff 2 seams in pit W05, a deposit previously mined using wheel loaders. The following figures were gained in a comparision between conventional mining (blasting and loading by the Caterpillar 992C front end loader ) and the WIRTGEN 3000 SM Surface Miner.
Area 35,794 (m2) Seam Thickness 1.9 (m) Volume 67,025 (fm3) Density 1.34 (t/m3) Tonnage of coal 89,813 (t) (mathematical basis) Tonnage of coal (ROM) 88,576 (t) Production (average) 247 (t/h) Production (maximum) 600 (t/h) Fuel consumtion 71 (l/h) Loading capacity of trucks 35/50 (t) Gradation:
|
lump
size:
|
>=75.0mm...........................12.3% |
|
53.0
- 75.0 mm............................8.7%
|
|
|
26.5
- 53.0 mm..........................23.6%
|
|
|
16.0
- 26.5 mm..........................14.4%
|
|
|
8.0
- 16.0 mm............................14.5%
|
|
|
4.0
- 8.0 mm...............................9.4%
|
|
|
2.0
- 4.0 mm...............................5.1%
|
|
|
<2.0
mm....................................12.0%
|
|
Front
end loader
|
WIRTGEN
|
|
|
Degree
of exploitation
|
70.0%
*
|
98.6%
|
| Ash content (from test drilling) |
6.0%
*
|
6.0%
|
|
Ash
content (ROM coal)
|
9.0%
*
|
6.5%
|
Compared with conventional mining techniques the degree of exploitation rose from 70.0 - 98.6%. This is an improvement of 43% or around 30,000 tonnes. In addition, coal quality was enhanced, the ash content dropping from 9.0% with conventional mining to 6.5% using the WIRTGEN 3000 SM Surface Miner. The increase of ash content was not more than 0.5% ( 6.0% in-situ, to 6.5% mined with Wirtgen Surface Miner).