Case Study 109: Bulk
Industry Sector: Conveying
Coal Conveying System


Allen Bradley ControlLogix
Allen Bradley PanelView Plus HMIs

Staneco Corporation designed a coal conveying system for a power plant. The system consisted of Stackout and Reclaim operations. The Stackout system consisted of the conveyors that removed the coal from railcars and delivered it to the stacks in the coal storage yard. The coal was removed from the cars by using a car dumper. Conveyors, running on rails, carried the coal to the stacker. The stacker moves down the rail a little at a time, adjusting its height as the coal pile builds. The Reclaim system takes the coal from the yard and conveys it to the power plant where it is distributed to a series of silos above the boilers. The system fills the silos, automatically moving the tripper, a small conveyor on rails, over the silo that needs coal. When the silos are near full the feeders stop, purge the coal off of the belts and then shut down the system. Safety devices are monitored; emergency pullcords run the entire length of the conveyor so operators can shut down the system if an unsafe condition is observed. Switches detect plugged chutes in the area of transition from one conveyor to the next; speed switches check for belt slippage; belt mis-alignment switches make sure that the belts are not running off of the pulleys; metal detectors keep tramp iron from getting into the boilers. Interlocking between conveyors prevents a running conveyor from dumping coal onto a stopped conveyor.

By utilizing the latest in both control and mechanical technology the end result provided the client a highly reliable system with throughput exceeding their expectations.

Conveying: Bulk