TenCate develops and produces materials that function to increase performance, reduce costs, and deliver measurable results by working with our customers to provide advanced solutions.
SCA Tissue's Cherokee Alabama, USA, waste water treatment system has minimal sludge storage, about six hours, with all sludge going directly to a dewatering table, followed by a screw press, which is then discharged to trucks for hauling to a landfill. There is no emergency spill basin. The screw press broke its shaft which took almost a week to repair. With only six hours of sludge storage, the mill had to shut down. Hauling the liquid sludge was not an option due to volume and finding an approved disposal facility. The challenge became how to keep the mill up and running while finding an economical way to dewater and store the volume being generated.
SCA purchasing agent remembered a neighboring mill using Geotube containers to contain and dewater sludge prior to mixing with bark and sending into their bark boiler. SCA contacted the mill and were able to borrow a Geotube container. With time running out, they placed the Geotube unit on the access road next to the sludge thickening building. Connecting a line from the bottom flange on the sludge storage tank allowed gravity flow to the Geotube container. Using the Geotube container, SCA personnel were able to get the mill back up and running on schedule without disrupting other plant activities.
Dewatering with Geotube technology is a three-step process. In the confinement stage, the Geotube container is filled with dredged waste materials. The Geotube container's unique fabric confines the fine grains of the material.
In the dewatering phase, excess water simply drains from the Geotube' container. The decanted water is often of a quality that can be reused or returned for processing or to native waterways without additional treatment.
In the final phase, consolidation, the solids continue to density due to desiccation as residual water vapor escapes through the fabric. Volume reduction can be as high as 90 percent.