Geotube Dewatering Technology contains and dewaters river sediments at large Water Treatment Plant in New Jersey - Case Study
River sediments and filter backwash sludge are annually dredged and dewatered in Geotube containers for beneficial reuse.
TenCate develops and produces materials that function to increase performance, reduce cost, and deliver measurable results by working with our customers to provide advanced solutions. And a unique high volume, low cost dewatering system from TenCate Geotube can provide a very effective way of dewatering river sediments and alum sludge.
River sediments and filter backwash sludge collect in an inlet settling basin at the 30 MGD New Jersey drinking water plant. Since 2004, Pond Recovery Services, Inc. has annually hydraulically dredged the sediments into Geotube containers for storage and dewatering. 60' circumference x 200' long Geotube containers are set up in a temporary dewatering cell adjacent to the basin. Initially, the contractor used a remote controlled cutter-head dredge pumping at 400 gpm. Subsequently, the dredge has been increased to a larger model pumping 1400 gpm. Care was taken to protect the basin's membrane liner.
Slurry was treated with polymer to flocculate the solids, capture the maximum suspended solids, return clear filtrate to the pond and optimize consolidation of the solids in the Gootube container. Clean effluent drained from the dewatering cell and was directed back to the basin. About 9,000 cubic yards of residual solids were removed from the basin between September and November of 2004.
After consolidation, each Geotube unit contained about 860 cubic yards of dewatered sediments, for a total of about 2,600 cubic yards of consolidated solids. The sediments were allowed to dewater and desiccate for 47 days before being excavated and trucked for beneficial reuse.