Customer: Palm Beach Aggregates
Location: West Palm Beach, Florida
The customer had an existing dragline crane operation on site approximately 4 miles away from the aggregate plant. They installed a 4 mile belt conveyance and screening system to replace the truck transfer of material from the dragline to the plant.
The system consists of 14 belt conveyors, one of which is a ½ mile long floating conveyor. Additionally as the material is transferred to the plant, it goes through a new screening process where the material is divided into base rock (which is distributed to stock piles by a track mounted mobile “Bird Stacker”) and plant feed. The plant feed can divert to a radial stacker or to the existing plant process.
The control portion of the automation system includes a main PLC processor and eight remote I/O rack Ethernet I/P locations communicating with each other via a fiber-optic network and 5.8 GHz wireless radios. Ethernet I/O was utilized to enable remote login for data collection and diagnostics through the 2 graphical HMI computers and use of Terminal Services or RDP.
The Operator sits in the dragline feed crusher where he can control the entire conveyance system. The graphics depict the actual system while displaying status, alarms, motor currents, trends and startup/shutdown sequence controls. All safety interlocks as well as hardwired shutdowns were considered and implemented in the PLC code and field logic.