AES PR – Total Energy Plant
- Owner: AES-Puerto Rico
- Project: Coal, Limestone and Manufactured Aggregate Handling Systems
- Location: PR – Total Energy Plant, Guayama, Puerto Rico
- Scope: Engineering, Procurement, Construction, Start–Up and Commissioning
Project Background
Roberts & Schaefer Company was awarded a turnkey contract from Duke/Fluor Daniel for engineering, procurement, construction, start–up and commissioning of the material handling systems at AES–PR’s Total Energy Plant in Guayama, Puerto Rico. The systems were successfully completed and in operation in 2002.
The materials handled include coal, limestone, and manufactured aggregate (bottom and fly ash product). The coal and limestone are received in self–unloading ships. The ash is shipped out in geared ships or ocean barges. The dock area consists of the coal/limestone receiving hopper with belt feeder and the aggregate ship loader. The single path series of conveyors with a length of 3,600 feet from the dock to the material handling areas are reversing conveyors and handle all three materials. The coal or limestone is conveyed from the 50,000–ton capacity ships at 3,000 TPH to the storage areas and the aggregate is conveyed at 1,800 TPH from the storage area to the 9,000–ton capacity ocean barges.
The coal handling stockout and reclaim system consists of two stacking tubes with a total pile capacity of 98,000 tons and a series of ten variable rate vibratory feeders located below the piles for reclaim at 720 TPH. The crusher house includes a surge bin, two variable rate vibratory feeders, and dual path 100 percent redundant cage–paktor crushers. The plant feed conveyor with a capacity of 720 TPH transfers the coal to the plant conveyor with a traveling tripper for delivery to the four silos of each unit. The coal handling system includes wet suppression, bag house dust collection, ventilation, and washdown for dust control.
The limestone stockout and reclaim system consists of a conveyor from the second coal stacking tube to the limestone stacking tube enclosed in a dome for dust and moisture control. The stacking tube forms a 60,000 ton capacity pile. A mobile equipment fed hopper with variable rate vibratory feeder loads the reclaim conveyor to covey the limestone at 60 TPH to the Limestone Preparation Building. The limestone system includes wet suppression, bag house dust collection, and ventilation for dust control.
The bottom and fly ash are combined from the ash silos and conveyed to the initial storage area. This manufactured aggregate (ash product) is reclaimed by mobile equipment to a hopper with a 1,800 TPH feeder breaker and sent to the ship loader via the reversing conveyor system. The shiploader is equipped with a telescopic spout and a retractable boom conveyor. The aggregate systems include wet suppression for dust control.
All unloading, stockpiling, reclaiming, crushing, and shiploading operations are controlled by a series of programmable logic controllers (PLCs).