Their challenge

This power generation client hired a competing firm to design, supply, and construct a truck dump system to support their relocated mining operation. The truck dump would allow haul trucks to drive on an earthen ramp, supported by retaining walls, over a hopper. The hopper would sit over a new feeder breaker which feeds a new overland conveyor. During construction the retaining wall failed, making the truck dump system unusable. The client was forced to install a temporary reclaim system that allowed the mine to operate at a reduced capacity. Salas O’Brien was brought in to provide a permanent solution.

Our solution

Utilizing a subcontracted geotechnical engineering firm, Salas O’Brien was able to diagnose the failed retaining wall and determined that a solution to maintain the truck dump operations as originally intended would not be cost effective. The client then asked Salas O’Brien to propose an alternative turnkey solution to return the mine to full operation. The proposed solution was to repurpose the truck dump hopper as a surge bin for the feeder breaker. Salas O’Brien’s design used a new drag chain reclaim feeder with a dozer push wall to feed the truck dump hopper. The push wall was installed on driven pipe piles to transfer the load through weak soils that caused the failure of the retaining wall. The design also had the new reclaim feeder discharge onto a new bin feed conveyor that feeds material into the existing truck dump hopper. This allowed the existing system to function as originally intended. The bin-feed conveyor was a custom design with a 72” belt width, reinforced impact zone, and was fully enclosed to handle the large lumps in the run-of-mine lignite coal. Salas O’Brien also integrated the new system controls into the existing overland controls system, as well as programmed upgrades to the existing system which improved flow rate control on the overland belt.