Literature Review & Summary Report Design Basis Memorandum
BCI Project No. 19-15089 September 2007
St. Johns River Water Management District Contract # SK940AA
system is fully automated, and operating status, yield and performance values, as well as alarms are continuously and automatically logged by an internal data acquisition system.
The Bucher hydraulic press system produces filter cake solids in the range of 30 – 40%. A side-by-side comparison with a belt filter press indicated that a hydraulic press can improve cake solids content by more than 25% compared to a belt filter press. Higher solids contents could be achieved by extending the batch time but this gives a significant reduction in throughput.
As with most mechanical dewatering systems, the need for settling basins, return water systems, and containment area restoration, as well as the piping and pumps to the settling area is eliminated.
The Bucher hydraulic press functions as a secondary dewatering step, necessitating a pre- thickening step; usually accomplished by a conventional thickener or clarifier. This technology must be considered a step in a more complex process and is not applicable as a stand-alone dewatering system. Additionally, return water will likely need treatment to remove dissolved phosphates prior to reintroduction to the lake.
Genesis Rapid Dewatering System
The Genesis Rapid Dewatering System is a continuous process providing dredging through dewatering in one integrated system. In comparison to more conventional dewatering devices, cake solids from the Genesis Rapid Dewatering System are much higher, generally in the range of 40-45% by weight, vs. about 25% for a press alone, and 50%-65% solids by volume. Return water is clear and turbidity levels are less than 30 ppm total suspended solids, which meet or exceed typical discharge standards. This is coupled with a state-of-the-art solids monitoring system and polymer instrumentation package. As with all technologies investigated, the Genesis RDS integrated technology accepts a dredge flow as low as 2% solids by volume.
The operational cost of the Genesis RDS integrated technology typically runs 30-50% less than more common dewatering techniques, including confined disposal areas and various pressure dewatering presses. The required operational site, or footprint, is only about 150 by 150 feet, enabling the mobile Genesis dewatering unit to set up in small parking lots, on golf courses, or on barges. No pits, ponds, or return channels are needed. Each mobile system is discrete in operation, emitting little noise or odor, and can be set-up and operational in 24-48 hours.
Return water will likely need treatment to remove dissolved phosphates prior to reintroduction to the lake.