New ideas and equipment may provide a more effective way of moving overburden
The coal production figures that some surface operations post are impressive, especially in the western U.S. What is more incredible is the amount of overburden they must move to mine that coal. If the stripping ratio is 7:1 or greater, then the mine needs to move seven times as many bank cubic meters (bcm) of rock to access the coal seam.
Traditionally, coal operators have relied on draglines as the primary loading tool to move overburden. Over time, draglines have proven to be the most cost-effective means for the job at hand. These machines, which are some of the largest machines to walk the Earth, consume as much electricity as a small town. Obviously, technological advances in control systems could improve operating efficiency and reduce electrical demand and the stress induced into the machine’s structure.