Engineering properties and leaching tendencies of reuse products containing lignite fly ashes

An alternative to disposing of at least part of the large quantities of ashes produced by lignite combustion in modern steam electric generating stations is to use them. If ashes are to be used, the reuse products must have acceptable physical properties and environmental characteristics. Laboratory studies were carried out to evaluate physical stability and leachate generation potential. Test materials representing four types of reuse were prepared in the laboratory. These were: Stabilized roadbase (fly ash plus lime); Soil stabilization (soil plus fly ash); Partial cement replacement (cement plus fly ash); and Asphalt filler (asphalt plus fly ash). Test specimens were prepared with three lignite fly ashes for each of the four reuse options. Physical stabilities of reuse products, as measured by standard materials testing methods, were acceptable to excellent in each case for two of the three ashes tested. Each ash yielded at least one acceptable reuse product.