The influence of processing variables: mixing time, waste/binder ratio and water/ solid ratio on the solidification/stabilization process of steel foundry dust has been studied. The characterization of the final product was based on the Toxic Characterization Leaching Procedure (TCLP) followed by the biotoxicity (bioluminescence assay) and concentration of the metals, Cr, Cd, Pb and Zn in the leachates. The final product characteristics depend mainly on the waste/binder ratio, as a function of the metal hydroxide solubilities. The results of this work allow one to establish the optimization of a solidification/stabilization process for steel foundry dust.
Andrés, A., Viguri, J.R., Bilbao, P. & Irabien, A. (1991a) Metal lixiviation of steel foundry dust. Chemistry for Protection of the Environment, Vol. 42 (L. Pawlowski, N. J. Lacy & J. J. Dlugosz, eds) New York, U.S.A.: Plenum Press, pp. 781-787.
2.
Andrés, A., Viguri, J.R. & Irabien, A. (1991b) Inertization of toxic wastes. Toxicological and Environmental Chemistry31-32, 593-601.
3.
Andrés, A., Ortiz, I. & Irabien, A. (1992) Characterization of toxic wastes. Application to steel foundry dust. Fresenius Environmental Bulletin1, 172-177.
4.
Boe (1989) Orden de 13 de Octobre de 1989 por la que se determinan los métodos de caracterización de residuos tóxicos y peligrosos (Spanish rule 13th October 1989, which develop the methods of characterization of hazardous wastes). In Boletin Oficial del Estado10, 1.
5.
Federal Register (1986) Toxicity characteristics leaching procedure (TCLP). 51, 216 Friday, November, pp. 40643-40654. U.S.A.
6.
Finholt, J.E., Thomson, M.E. & Connik, R.E. (1981) Hydrolytic polymerization of Cr(III), a trimetric species. Inorganic Chemistry20, 2279-2285.
7.
Jones, L.W. (1988) Interference mechanisms in waste stabilization/solidification processes. EPA-DW/219306080-01-0. U.S. Environmental Protection Agency, Cincinnati, Ohio, U.S.A.
8.
Montgomery, D.M., Sollars, C.J. & Perry, R. (1988) Cement-based solidification for the safe disposal of heavy metal contaminated sewage sludge. Waste Management and Research6, 217-226.
9.
Poon, C.S., Clark, A.I., Peters, C.J. & Perry, R. (1985) Mechanisms of metal fixation and leaching by cement based fixation processes. Waste Management and Research3, 127-142.
10.
Shin, H., Her, N. & Koo, J. ( 1988) Design optimization for solidification of hazardous wastes . Hazardous Waste & Hazardous Materials5, 239-250.
11.
Thompson, M. & Connick, R.E. (1981) Hydrolytic polymerization of Chromium (III), two dimeric species. Inorganic Chemistry20, 2279-2285.
12.
Wagner, T.P. (1991) The Complete Guide to the Hazardous Waste Regulations. New York, U.S.A.: Van Nostrand Reinhold Company, p. 38.
