Use of Additives in Minimizing the Flow of Impounded Fly Ash Slurries

Coal ash is one of the largest industrial waste products generated in the United States. Since 1967, several failures in ash impoundments have been reported, releasing millions of gallons of impounded fly ash slurry resulting in loss of life and mass environmental destruction. Several studies have been carried out to understand the flow behaviors of fly ash slurries. This study evaluated the flow behavior of fly ash slurries with two additives: polyacrylamide and synthetic fibers. Two different types of tests, rheological and flow tests, were performed to assess the flow behavior of two hydrated fly ash slurries. An anionic polyacrylamide and G-Nano fibers were used to modify the flow behavior of fly ash slurries. The results showed that the addition of additives increased yield stress and decreased the flow of fly ash slurries.