Trace elements deportment in gold process solutions

J. Kyle; V. Gella; P. May

The deportment and speciation of trace elements during mining and minerals processing is becoming an area of increasing concern with regards to potential health and environment risks within the immediate vicinity and surrounding area of mining and minerals processing operations. This concern also extends to the transport of concentrates and other products from site to other facilities for further processing. In many cases the hazards associated with trace elements in the ore are exacerbated through their concentration in the processing plant. In Australia, the National Pollutant Inventory (NPI, 2010) lists antimony, arsenic, beryllium cadmium, chromium (III&VI), cobalt, copper, cyanide, lead, manganese, mercury, nickel, selenium and zinc as monitoring targets. From NPI data, the main trace metal emissions to the environment from metal processing operations are generally lead, arsenic, antimony and cadmium. Other trace elements of possible concern are mercury, bismuth, selenium and tellurium. However, little is known about the deportment and speciation of these trace elements in gold processing solutions, and how they vary in the leaching, carbon adsorption and tailings disposal facilities. The use of chemical equilibrium studies can enhance our basic understanding of the deportment and speciation of trace metals under conditions present in gold processing solutions, and assist in laboratory and field investigations. This paper presents some initial results from an initial two-year study into the deportment and speciation of trace metals in gold processing solutions. Although equilibrium models can be very useful in determining the deportment and fate of trace metals in process solutions, it must be remembered that these models have a number of limitations. The accuracy and precision of the modelling is very dependent on the thermodynamic database of from which the models are generated, and the range of conditions for which the data is available. In addition, models based on thermodynamic data may in some instances be unrealistic for processing solutions which often have a short residence time, and for which the speciation of metals may be governed more by kinetic than thermodynamic factors. For these reasons, care must be used in the interpretation of the information generated by the models and should, where possible, be confirmed by plant data or by laboratory tests.

Trace elements deportment in gold process solutions

Files and links (2)

Abstract

Details

Metrics