It is commonly known that copper smelter terms include penalties if the concentrations of elements,rnsuch as arsenic, mercury and fluorine, exceed stipulated limits. It is less commonly known that thernbehaviour of these elements in the smelters can depend on the processes used to treat the concentrate.rnThe principle behind the penalties is to compensate the smelters and refineries for additional costsrncaused by the presence of the penalty elements, but these costs will vary depending on the processrnused and the location of the smelter.rnThe issues caused by the minor elements include effects on the occupational health of smelterrnworkers, increased environmental disposal costs, increased operating costs and reduced cathoderncopper quality.rnThe effects of minor elements can be surprising. High levels of arsenic in concentrate are consideredrnundesirable, but some smelters add arsenic to anode copper to improve the performance of thernrefinery.rnExcess concentrations of some elements will result in rejection of concentrates by smelters. China hasrnblanket import bans on copper concentrates with concentrations of lead, arsenic cadmium, fluorinernand mercury exceeding specified levels.rnThis paper will review the behaviour of minor elements in smelters and refineries, explaining therndeleterious effects of each of them, to provide a greater understanding for people and organisationsrnwishing to market copper concentrates.
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