Experimental study of chemical treatment of coal fly ash to reduce the mobility of priority trace elements

An appraisal of the potential use of fly ash for reclaiming coal mine spoil

“…Bhattacharyya et al (2009) used ferrous sulphate and calcium carbonate to immobilize the trace metals in FA. The overall mobility reductions achieved for As, B, Cr, Mo, Se and V were 23-72%, 43-80%, 45-77%, 21-90%, 41-85% and 41-53%, respectively.…”

Characterization and comparison of leaching behaviors of fly ash samples from three different power plants in Turkey

“…Additionally, trace element concentrations increase due to the ignition of carbon as carbon dioxide [8,9]. As a result, fly ash contains significant amount of hazardous leachable elements such as As, B, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Se, Sr, Ti and Zn, as well as a great deal of major element compounds as oxides, hydroxides and sulfates of iron, aluminum and calcium [10,11]. Some studies also indicate that heavy metals favorably concentrate on the particle surfaces, making them more easily to be extracted from fly ash by the contact with aqueous solution in ponds and landfill areas [7,9,[11][12][13].…”

“…Some studies also indicate that heavy metals favorably concentrate on the particle surfaces, making them more easily to be extracted from fly ash by the contact with aqueous solution in ponds and landfill areas [7,9,[11][12][13]. In addition, there are a great number of studies [9][10][11][12][14][15][16][17][18][19] on the leaching behavior of different elements from fly ash. Dissolution behavior of the elements in leaching environments mainly relates to the particle size, surface area, leaching solution and fly ash pH, initial concentrations of the elements, leaching period, solid/liquid ratio, morphological structure and the other features of the leach medium.…”

“…Dissolution behavior of the elements in leaching environments mainly relates to the particle size, surface area, leaching solution and fly ash pH, initial concentrations of the elements, leaching period, solid/liquid ratio, morphological structure and the other features of the leach medium. If not properly disposed of, these elements can cause a risk into the environment that consists of soil, groundwater and surface water [2,9,10,20,21]. Dissolution of the elements from fly ashes is a slow operation in which the solid-liquid equilibrium cannot be reached even after long contact time [7,11,17].…”

Leaching behavior of selected trace elements in coal fly ash samples from Yenikoy coal-fired power plants

“…The reuse of coal fly ash for different purposes has spurred interest in understanding its environmental impact with focus on metal release [9,13]. Under favoring conditions, a considerable amount of these trace elements can easily be leached out from the surface of fly ash particles by the interaction with water in ponds or landfills [14,15]. There are large numbers of papers on prediction of leaching behavior of metals from coal fly ash.…”