Geotube Containers Offer Innovative Solution for Disposal of Coal Mine Slurry Waste - Case Study
TenCate helps North River Mine continue processing coal by utilizing first ever large-scale Geobag disposal method.
In 2007, the North River Mine coal processing plant in Berry, Alabama was in a bind. Due to new regulatory restrictions, available area, and construction scheduling, the plant was facing a possible interruption of the primary disposal methods of its refuse - a waste stream of almost 1.5 million gallons of slurry per day. The mine needed to continue processing coal for shipment in order to meet customer needs, however conventional disposal methods of surface impoundment or injection into abandoned underground mine workings were not possible. An alternative disposal method was necessary for the plant to continue operation.
Mike Windle, Plant Supervisor at North River Mine, began evaluating new disposal methods. According to Windle, Geotube technology stood out immediately. 'The Geotube method had multiple benefits of containment and dewatering, stability of the dewatered cake for reclamation of the site,' said Windle, 'and there was no need to rehandle the materials.' Since Geotube containers were already being used to successfully dewater various types of sludge wastes, it was suggested that Geotube technology could provide the processing plant with the waste disposal they needed.
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. TenCate^'s Geotube technology has been used to deliver high performance solutions around the globe in more than 50 countries. Over 2,000 dewatering projects have taken advantage of Geotube containers since 1991.
To determine if Geotube technology would dewater the waste slurry to an acceptable moisture content, full-scale tests were conducted at the mine in August 2007. Two 100-ft. long test bags were used, along with a chemical treatment pump, tanks, and pipe manifold to allow for required polymer injection Slurry was pumped directly into the bags from the preparation plant underflow.
A volume of about 500 gallons per minute was processed alternating between the two containers. As the bags were filled with the slurry mixture, clear water flowed from them draining into the wastewater sediment pond below. The effluent was almost completely clear. After roughly two days, water ceased to flow from the bags and they were stable. The test proved successful, and design began for a full-scale dewatering set-up.