Assessment of the Leaching Behaviour of Fly Ash from a Cobalt Smelter, Zambia
نویسنده
چکیده
The leaching characteristics of fly ash from a cobalt smelter were studied as a function of pH and time using the pH-static leaching test (CEN/TS 14997, pH range 5-12) coupled with mineralogical investigation and speciation-solubility modelling. Two sets of experiments with different equilibration time (48 h and 168 h) were performed. The leaching of metals showed typical U-shaped curves with the highest amounts released at pH 5 and increased concentrations at pH 12. Generally, no significant differences occurred between the 48-h and 168-h leaching. The main solubility-controlling phases in this system were CaCO3 and CaSO4·2H2O. This approach represents a useful tool for assessing the leaching behaviour of waste materials over a wide range of conditions.
منابع مشابه
Leaching of Metals from Metallurgical Wastes in pH-static System: an Experimental Approach
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