The stacker reclaimer distributes the coal in a field that has coal piles segregated by volatility. Operators maintain up to six coal piles. Bethlehem Burns Harbor keeps about 20 days' worth of coal in the field. When coal arrives, workers enter its type into the coal-handling computer program. The system then tracks the coal as it travels to the stacker reclaimer.
Sensors monitor the location of the stacker reclaimer.
A worker operates the stacker reclaimer, but if it isn't in the proper location to deliver coal to the correct coal pile, the computer system freezes the stacker's controls. Before the computer controls were installed, the stacker-reclaimer operator manually identified the proper coal piles. It may be late at night and raining, making the exact location of the right pile difficult to determine. Having coal in its correct pile helps ensure the proper blend of coal at coke batteries. Low-volatile coal makes for strong coke, a necessity for low yield losses as coke travels from the coke battery to the blast furnace.