Modern metallurgy pays more attention to chemical processes safety of staff and nature environment. One of the most hazardous branches in metallurgy is gold ores cyanidation. Researches on possibility to avoid cyanide leaching are carrying out during last thirty years. Cyanide competitors are thiosulphate and thiourea solvers. Within international cooperation between National Mineral Resources University and Lappeenranta University of Technology researches are devoted to tiosulphate leaching improvement. Main efforts are forwarded on process chemistry, however mass transfer processes of heterogenic systems are important as well. Therefore their optimization is planned to achieve by means of computer modeling based on particle image velocimetry.
More and more attention is paying to research of feasible cyanide alternative leaching techniques due to increasingly growing concern to Mother Nature. After some serious cyanide accidents some countries have campaigned to ban cyanide in gold mining industry. Political alignments and concern about environmental have been reasons to find good and less-toxic alternatives to cyanide. One of the most promising leach reagents is stated to be thiosulphate because of its benign properties. Moreover it is suitable for sulphide and carbonaceous ores which present a problem for cyanidation. In the present paper number of experiments on research of thiosulphate leaching kinetic study as well as pretreatment of gold concentrate by wet oxidation with following leaching tests is presented.
Computer based modeling is increasingly strengthening its position in equipment designing, especially unique meeting particular needs of production line or certain plant of metallurgy. There are several reasons for that such as economic benefits, wide range of geometry available to be built and possibility of comprehensive study on materials reliability as well as virtual model testing in working regime. One of the most applied and therefore permanently developed program packages for fluid behavior modeling is Fluent product of ANSYS company. The package is being used for creation first physical and in future chemical model which will be capable to describe and predict process and reactions behavior of high quality taking place in gold leaching gas-liquid reactor with thiosulphate using.