A new cost effective way to process nickel laterites known as the DNi Process will be thoroughly examined by a test plant currently being built in Western Australia. The creation of this test plant is the result of an ongoing four year research collaboration between the Parker Cooperative Research Centre for Integrated Hydrometallurgy Solutions (Parker Centre) and nickel processing SME company, Direct Nickel (DNi).
Through its research partner CSIRO Process Science and Engineering, the Parker Centre has worked with DNi to significantly enhance a new, cost effective way to process nickel laterite ores.
Parker Centre Researcher, Dr David Robinson says unlike traditional nickel sulphide ores, mineralogically complex and usually low grade nickel laterites are difficult to commercially process, with flowsheets being considerably different for each of the various laterite ore types.
“Add to this the geographic and logistic challenges and the water and energy demands, then economically processing nickel laterites presents an ongoing development challenge,” explains Dr Robinson.
“However as nickel sulphide ore deposits become depleted, the lower grade nickel laterites are fast becoming processing priorities for mining companies,” he adds.
The nickel laterite ore processing research collaboration has fine tuned a new processing regime that replaces the need to consume large amounts of sulphuric acid often at high temperatures and pressures by using very small quantities of nitric acid under normal atmospheric conditions.
“Having a reagent recycle process that uses nitric acid instead of sulphuric acid has created an opportunity for lower grade ores to be profitably treated, potentially converting many millions of tonnes of Australian nickel laterite ores into economically attractive material. The DNi Process can treat all of the laterite profile through one flow sheet making it particularly attractive in sustainably maximising resource utilisation.
“We have tested all stages of this process in the laboratory but the Test Plant will prove it on a continuous basis,” says Dr Robinson.
Located at the Australian Minerals Research Centre (AMRC) in Perth, the one tonne of nickel laterite ore per day test plant will operate 24 hours a day in campaigns of 10 to 15 days to continuously demonstrate the DNi process to fine tune the estimation of operating costs.
Expected to be operational by early 2012, the Parker Centre participants CSIRO and DNi anticipate using the test plant for several years to test and optimise the process on various ore bodies, and provide important information for the design, commissioning and ramp up of commercial operations.
"When successfully demonstrated, the DNi process will change the economics of nickel laterite processing and has the potential to prolong operational life or lead to the development of new projects, new employment opportunities and increased company revenues,” says Dr Robinson.
This article was provided by Ferret - www.ferret.com.au .