Effect of industrial residue combinations on availability of elements

• Published in: Journal of hazardous materials 2014-07, Vol.276, p.171-181
• Main Authors: Brännvall, Evelina, Zamora, Carles Belmonte, Sjöblom, Rolf, Kumpiene, Jurate
• Format: Article
• Language: English
• Subjects: Air Pollutants - analysis; Applied sciences; Avfallsteknik; Biosolids; Cadmium; Chemical engineering; Crystallization, leaching, miscellaneous separations; Element availability; Exact sciences and technology; Exchange; Fertilizers; Fertilizers - analysis; Fly ash; Industrial residue combinations; Magnesium; Manganese; Other industrial wastes. Sewage sludge; Peat; Pollution; Residues; Sequential element extraction; Trace Elements - analysis; Urban and domestic wastes; Waste Science and Technology; Wastes
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2014.05.026

•Beneficial combination of fly ash and biosolids.•Nutrient availability increase.•Potentially toxic element availability decrease.•Measured element availability was differed from the calculated leaching potential. Industrial residues, such as fly ashes and biosolids, contain elements (e.g., N, P, K, S, Ca and Zn) that make them a viable alternative for synthetic fertilizers in forestry and agriculture. However, the use of these materials is often limited due to the presence of potentially toxic substances. It is therefore necessary to assess and, when warranted, modify the chemical and physical form of these and similar waste materials before any advantages are taken of their beneficial properties. Biofuel fly ash, municipal solid waste incineration (MSWI) fly ash, biosolids, peat, peat residues and gypsum board waste were combined in various proportions, and this resulted in increased leaching of N, P, S, Cu and Mn, but decreased leaching of Ca, K, Mg, Cr, Fe, Ni, Zn, Al, As and Pb. Chemical fractionation revealed that elements Ca, K, Mg, S and Mn were predominantly exchangeable, while the rest of the elements were less mobile. Cadmium was mostly exchangeable in MSWI fly ash, but less mobile in biofuel fly ash mixtures. Recycling of MSWI fly ash in the mixtures with fertilizers is considerably less attractive, due to the high levels of salts and exchangeable Cd.