In order to meet the difficult criteria needed for liner dredging, Eddy Pump Corporation will utilize a custom dredging system capable of meeting the stringent requirements of this challenge. This technology has been proven as an effective tool on many projects in the United States and around the world. The Eddy Pump operates by harnessing the power of a tornado’s rotating column of energy or eddy making it the most powerful high solids pump on the market today. The Eddy Pump offers many advantages in the field of dredging, including the ability to handle a higher percentage of solid and highly viscous material than any existing centrifugal pump.
The Eddy Pump is precisely engineered to create a synchronized, swirling column of fluid in the center of its intake pipe which in turn agitates the material in suspension and causes it to travel up along the sides of the pipe by the reverse flow of the eddy current. These hydrodynamic principles allow the EDDY Pump to remove materials at a rate of 40-80% solids in situ by weight with production rates between 300-350 cubic yards per hour.
The Eddy Pump technology was contracted by one of the largest Municipal Sewage Treatment Plants to pump digested sewage sludge. Due to the physical properties of digested sewage sludge the material is particularly difficult to transfer efficiently and economically using conventional methods such as pumping with centrifugal pumps or dredging with draglines, clambuckets or backhoes. Centrifugal pumps typically can only handle sludge containing only about 4-6 percent total solids by weight. Since transportation costs represent the vast majority of the total sludge handling budget, it is desirable to maximize the total solids by weight (TSW) of the sludge being transported. For example, if TSW can be increased from 6 to 14 percent, transportation cost could be cut almost in half; reduced sludge volume can also lower costs associated with landfill disposal. The Eddy Pump exceeded all expectations by operating 95% of the work day at rates of 100 ft of head while pushing 18.6% TSW sludge 1,320 ft at rates averaging 2,500 gpm. These unheard of pumping capabilities were achieved without any assistance of external intake-feeder devices or booster pumps and could fill a 21-ton payload dump truck with concentrated sludge in less than 3 minutes.
These impressive numbers are achieved through the Eddy Pump’s hydrodynamic principles which creates a column of swirling fluid close to the bed of sediment, causing the materials to swirl upward into the pump and then into the discharge line without the need for a cutterhead. The ability to remove the materials without the need for a cutterhead has the monumental advantage of being able to operate close to the plastic liner without damaging it.
The ability to remove the sediment from the pond without damaging the poly-liner is of monumental concern for this project. For this reason Eddy Pump Corporation utilizes its PLC (programmable logic controller) ground sensing technology which can achieve vertical accuracy in the range of +/- 2 to 4 cm. The PLC monitors the down pressure that is exerted on the bottom by the pump head and either raises or lowers the head to maintain the down pressure programmed by the operator. The target sediment is immediately removed by the powerful suction of the Eddy Pump. This allows the smooth level cut head to get down to the plastic liner and ride on top of it like a wheel with out cutting into it like conventional dredging equipment. This technology developed by Eddy Pump Corporation allows the dredge to remove all of the sediment in the pond and maximize production without damaging the plastic liner. Underwater videos and inspection reports confirm the accuracy. On the other hand Cutterhead dredges do not have this capability and will damage the liner.
Eddy Pump Corporation has developed a cable deployment system that positions itself from blocks or fixed points on shore. This technology enables the dredge to maneuver effectively throughout the canal while having no impact on the plastic liner. Conventional spud positioning technology would compromise the liner.