Dredging Sediment from a Settling Pond into Geotube® Containers
This steel mill in Iowa chose to dewater the residual in their settling pond using Geotube® containers. A dredge pumped approximately 4,000 cubic yards of material at 650 gallons per minute through a 6-inch pipeline. Two polymers—Solve 426 (coagulant) and Solve 154 (flocculant)—were injected to enhance flocculation and water clarity before the solids entered the tubes. The system effectively dewatered the residual, with clean filtrate returned to the pond and the filled Geotubes prepped for landfill disposal.
DOWNLOAD PDF Applications & ProductsGeotubes® and PolymerServicesTurn Key DewateringIndustryIndustrialLocationIowa, USA
Beginning Pond Conditions
The pond prior to removing the water and residual.
Emptied Pond
Pond after the residual was removed
Example of Flocculation
Sample jar of the residual treated with Solve 216B with great water release, clarity, and flocculation.
Hydraulic Pump
This 6” hydraulic pump was lowered into the first pond as the project begins.
OBJECTIVE
A dredge pumped the residual from the settling pond into Geotube® containers so it would dewater and pass paint filter testing and then be hauled to a landfill. The mill would then have a clean pond for proper settling in the years to come.
CHEMICAL CONDITIONING
A representative sample of the pond sludge was tested by a WaterSolve technician in the WaterSolve laboratory. Dewatering polymers were evaluated based on water release rate, water clarity, and flocculent appearance. Solve 216B was selected as the best flocculent to produce the water release, clarity, and flocculation needed for this residual.
GEOTUBE® TUBE CONTAINER SIZING
Geotube® containers are manufactured from high strength polypropylene fabric and designed to allow effluent water to escape through the pores of the fabric while retaining the chemically conditioned solids. Measurements of the residual in the ponds indicated there was 4,000 cubic yards of residual to be removed. WaterSolve recommended 3 Geotube® containers 120’ circumference by 100’ long totaling 4,380 cubic yards of usable space for this project.
THE RESULT
The dredge contractor used a 6” pipeline to transfer the residual from the dredge to the Geotube® containers. The Solve 426 was injected into the pipeline at a rate of 6-gallons per hour and the Solve 154 was made-down and injected at a rate of 6 to 9 gallons per hour. The filtrate water was pumped back to the settling pond with a 4” hydraulic pump. The environmental manager on site was very happy with the clarity of the filtrate being pumped back to the pond. Cattails around the perimeter of the pond offered a challenge for the dredge operator, but the project was very successful in getting the pond clean and the residual dewatered by the Geotube® containers.
