Advances in the application of the BIOX (R) Process for refractory gold ores

The Biological Oxidation (BIOX(R)) Process for the treatment of refractory gold ores was commercialized in 1988. During the last decade, the technolog y has developed into a mature, commercially viable process, with five addit ional operations commissioned, including operations at Sao Bento in Brazil, Harbour Lights and Wiluna in Australia, Ashanti in Ghana and Tamboraque in Peru. With ongoing development, the efficiency and cost effectiveness of t he process have both improved making it an attractive alternative to conven tional refractory treatment processes such as roasting and pressure oxidati on. The bacterial culture is robust and can withstand the normal fluctuatio ns experienced on an operating plant. The plants are simple to operate, mak ing it ideal for remote areas. The scale-up potential of the process has be en proven, and it can be applied to large refractory ore bodies. The proces s is environmentally friendly. Neutralization of plant effluents produces p recipitates that comply with the most stringent environmental regulations.