Fly Ash Sludge Research Articles

Stabilization of Steep Coal Waste Banks with a Sludge-Fly Ash Mixture

Stabilization of Steep Coal Waste Banks with a Sludge-Fly Ash Mixture

Evaluation of Paper Mill Sludge-Fly Ash Mixtures as Potential Amendments for Vegetation Establishment on Mine Land

Evaluation of Paper Mill Sludge-Fly Ash Mixtures as Potential Amendments for Vegetation Establishment on Mine Land

Revegetation of Steep Coal Waste Banks Using a Sewage Sludge-fly ash Amendment

Revegetation of Steep Coal Waste Banks Using a Sewage Sludge-fly ash Amendment

Revegetation of a contaminated zinc smelter site

Over 800 ha of forest vegetation are dead on Blue Mountain at Palmerton, Pennsylvania. The major cause was emissions of Zn, Cd, Cu, Pb, and SO 2 from a zinc smelter operating since 1898. In 1985, a research effort was initiated to develop a remedial action program to mitigate the environmental damage. Field plot studies were conducted to determine the feasibility of using mixtures of dewatered municipal sludge and fly ash as amendments to facilitate the establishment of vegetation on the highly contaminated soil. Three mixtures of sludge (S) and fly ash (FA) were evaluated (1S:1FA, 2S, and 3S:1FA). The amendments were applied on 0.4-ha plots in May 1985. Five grass and legume seed mixtures were hydroseeded on subplots for evaluation. In addition, seedlings of 10 tree species and hybrid poplar cuttings were planted on the plots. After two growing seasons, results indicate that all three sludge-fly ash mixtures were successful in facilitating vegetation establishment.

Solidification of Sludges with Portland Cement

Raw primary sewage sludge and a chicken manure was solidified by mixing with fly ash and Portland cement. By varying the proportions of sludge solids, fly ash, and cement in a mix, it was possible to control the time required for final set, and the physical properties of the resulting solid matrix. A maximum of 3.3% of the input phosphate was leached from the matrices over a 15-day period. Phosphates are efficiently incorporated into the solid matrix.