The dewatering plant was used to remove CCB material from the process and remove the water from the CCB material. This facility has the largest drum filters ever built in the country. The facility was built <5 years ago.

Lime and fly ash were drying agents for dewatering. Plant is electric, not gas fired.

PURPOSE: To decommission the LBR impoundment we needed to construct a dewatering facility that will convert the CCB material to a dry residual waste that must be suitable for transport and landfilling.

The CCB slurry from the operating units will be dewatered using Rotary Vacuum Drum Filters (VDF). A paste thickener will be used to dewater the FOG fines thickener underflow. The water will then be sent back to the units to provide makeup water to the unit thickeners. The new system will have no liquid discharges to the Ohio River as all water leaving the process will be bound to the solid CCB material.

The main process for dewatering the CCBs are the Vacuum Drum Filters (VDF). The underflow from the thickeners will be sent to the filter feed tank and then pumped to the VDFs. Each VDF has a dedicated liquid ring vacuum pump. The filter cake from the VDF drops onto a conveyor system that can deliver the solids to one of two pug mills. The pug mills mix the dewatered CCB and paste from the paste thickener with crushed lime and dry fly ash from unit 3. The material is then conveyed to a barge or to the storage pad.​

The pug mills are rated for a max throughput of 626 ton/hr. This can accommodate 2 or 3 drum filters feeding a single pug mill. The system also has three large tanks, all three Tanks are the same size 50’ high by 60’ wide, with a capacity of 1033006 gallons. Maximum design height is 49 feet with a temperature of 140 degrees down to – 18F degrees. Tanks were completed in 2015 when system was placed in service. ​

The system also has a Stacker and Barge Loading equipment. When the barge load system is unavailable, processed CCB material can be placed on the storage pad using the stacker. The storage pad holds up to 37,000 tons of dewatered CCB material.​ Material that has been placed on the storage pad will be reclaimed using mobile equipment. The feeder breaker consists of a hopper, conveyor, and delumper. The max reclaim rate for the feeder breaker is 1000 tph.​

The barge load system consists of the barge load conveyor, telescoping chute, shuttle barge, and topper conveyor. While a barge is being filled, the shuttle barge will move the barge back and forth to ensure that it is filled evenly. When the active barge is full, the system can switch to a waiting empty barge using the topper conveyor. The topper conveyor is only used during these transitions. The telescoping chute can raise and lower to accommodate changes in river elevation.