Geotube dewatering technology aids in lagoon cleanout, expands capacity, and helps address environmental concerns—often at a reduced cost compared to other methods.
Pulp and paper mills have to manage water to be successful. That includes planning and executing efficient dewatering operations.
And a technology from TenCate has proven itself highly successful in pulp and paper facilities throughout North America. Geotube dewatering technology has been used for lagoon cleanout, dewatering process waste, and even environmental remediation.
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.
There are numerous examples of success.
In Niagara, Wl, a Stora Enso mill uses 7,500,000 gallons per day of river water to make pulp & paper. Before the water can be used in process, it first must be treated to remove solids. Solids are removed from the water by treating it initially with alum, and then a flocculent, which allows them to settle in a 2,000,000 gallon settling tank system.
This tank requires yearly cleaning to ensure quality water for the paper making process and performance of equipment on the bottom of the tank. Cleanout is a significant operation, which requires emptying the entire 2,000,000 gallon tank that contains approximately 60,000 to 80,000 pounds of solids. The solids must be consolidated as much as possible to reduce disposal cost
Historically, the tank was decanted to the river, ensuring the solids level to be within permit levels. The sludge was then slowly flushed and washed to the clarifier for retreating, then sent to the primary solids pressing area. The solids processing area, however, was not designed for alum sludge. This procedure increased chemical cost caused upsets in the clarifier and pressing systems, and created time restraints. However, by using Geotube dewatering technology, Stora Enso was able to completely flush and clean the tank out in record time, without sending high solids loads to other areas.
Upon testing the filtrate, the solids were so low that Stora Enso was able to send the filtrate directly to the river instead of the clarifier, reducing the loading on other treatment areas. The Geotube dewatering technology system at Stora Enso has the capacity to contain several years of alum sludge settling from the tank clean-outs.
At the Lake Utopia mill in St George, New Brunswick, a black liquor lagoon was about to overflow into an adjacent river. The sludge level needed to be lowered immediately. Geotube dewatering technology accomplished this in less than seven days.