Potential of Fly Ash and Organic Wastes for Uses as Amendments to Agricultural Soils: A Review

Vast quantities of coal residues and fly ash require proper disposal and utilization. Fly ash contains high concentrations of various useful and toxic elements. Runoff from a coal pile and its leachate splits into various ionic species as it enters the soil and ultimately contaminates the groundwater. A portion of the accumulating fly ash is used in concrete as pozzolanic material. Studies reveal that amending the soil with 20–25% fly ash-compost mixture proves beneficial for the growth of certain crops, particularly corn and sorghum without any deleterious effects. Fly ash-compost (from organic wastes) mixture applied to the soil minimizes the uptake of certain toxic elements.