Africa is showing great promise in its strategies to approach ferrous metal beneficiation to maximise the utility of existing ore deposits. South Africa is leading the way after President Jacob Zuma announced an official government strategy in 2011, stating ‘beneficiation was a priority in order for the country to ‘reap the full benefits of its abundance of commodities’.
While there are a number of challenges for implementing these new initiatives, the benefits of overcoming these hurdles is likely to be extremely lucrative over the long term.
We spoke with Dr Liming Lu, Principal Research Scientist leading CSIRO Mineral Resources Flagship’s research in iron ore sintering and pelletising, as he prepares to travel to South Africa for the 2nd Iron Ore Beneficiation Africa conference. Dr Lu will share his expertise in the evaluation of iron ore for iron ore production.
CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.
Firstly, could you tell us a little about CSIRO’s Mineral Resources Flagship activities and how CSIRO works and engages with industry?
The CSIRO Mineral Resources National Research Flagship, formerly the Minerals Down Under Flagship, was established in 2007 to provide a national platform to focus Australian research at scale and across the breadth of the innovation system. This enables a focus on the key challenges facing the minerals industry in Australia and the ability to build links to the global market place for Australian innovation. While our focus is on optimising outcomes for Australia, our project portfolio is global in scope. It conducts research across the mineral industry value chain from greenfield exploration to mine site rehabilitation. This alignment has helped us to work and engage with industry broadly. Almost half of the annual budget is derived from external revenue from our industry partners.
The pilot-scale sintering facility at the Queensland Centre for Advanced Technologies is an integral part of your team’s work, to develop technologies that can unlock Australia’s lower-grade, but plentiful, iron ore resources. Can you tell us about the sintering facility, the aims and objectives for the centre and how success is measured?
The Queensland Centre for Advanced Technologies (QCAT) is a collaboration between CSIRO and the State Government of Queensland to expand and diversify the research and development activities undertaken by CSIRO in Queensland. The Centre commenced operation in 1992 and was officially opened in 1993. Following the construction of new facilities, Stage Two was opened in 2000. Over the years, QCAT has provided a synergistic environment for ground breaking research, innovation and technology development between research providers, government institutions and industry. It is Australia’s largest integrated research and development precinct for the resources and associated advanced technology industries and has attracted tenants from CSIRO, research providers and industry partners.
CSIRO has developed sophisticated laboratory and pilot scale facilities for fundamental and applied research in sintering and pelletising. The pilot scale sintering facility is one of the key facilities to carry out sintering research under simulated conditions occurring in the industry process. It is fully automated and instrumented with sensors for measuring temperature, flow, pressure and gas composition, and has been widely used for maximising resource utilisation, developing new technologies for counteracting rising gangue minerals and investigating emission reduction technologies.
What are the most promising techniques and technologies that you and your team are currently examining through the pilot-scale facility?
One of the key areas that the QCAT Carbon Steel Futures Group has been working on is to the development of technologies and relationships to link ore characteristics with their downstream processing performance. This requires not only advanced characterisation techniques that provide results that are consistent and relevant to the downstream processing performance, but also a large database. The Group’s pilot scale facilities are an integral part of this initiative to extend our existing database and validate the research findings.
Rising ore alumina content is another key focus of the Group as alumina has a significant impact on the productivity and energy efficiency of iron making processes. Empowered by the pilot scale facilities, the Group is currently working on various techniques for alumina reduction and counteracting the adverse impacts of alumina on the sintering and ironmaking processes.
There are a number of challenges associated with implementing beneficiation initiatives, for example processes are often high in energy and water requirements. From your understanding, are there any techniques and technologies that you see potential for being utilised in Africa ferrous projects?
Historically, South African iron ore producers are among the leaders in deploying available technologies to improve the process performance and reduce cost and water consumption. Dry separation technologies, such as air classifiers and dry magnetic separation, may find applications in areas where water is scarce. Fine grinding technologies have also been successfully used in the base metal and nonferrous industries to reduce the energy consumption of grinding significantly. Depending on the characteristics of the resources available, the suitability of these technologies in iron ore processing need to be reviewed.
“Blend optimisation is key for the sintering process” Can you elaborate further on this?
Due to the ongoing demand and increasing depletion of high-grade iron ore resources from large deposits around the world, iron ore producers worldwide are developing smaller size deposits to maintain current export levels. On the other hand, it is almost impossible to produce a high performance sinter mixture displaying the required characteristics from one single ore. Blending is therefore one of the most effective options being used, not only by iron ore producers to ensure the long term stability of their products while increasing production, but also by the steel industry to reduce operation costs while maintaining process performance. However, due to the interactions between the component ores, the performance of the resultant blend can be very different from the summation of the blend components. Blend optimisation involves the design of a blend by selecting the blend components to support each other to achieve the required overall balanced metallurgical performance of the final product at a relatively low cost. To do so, a fundamental understanding of the key characteristics of iron ore fines and their interactions is required, which is also one of the key areas we are researching.
What conversations are you looking forward to having with your industry peers at the 2nd Iron Ore Beneficiation Africa?
I look forward to meeting and talking to our South African counterparts on their experience in upgrading and utilising their resources and the challenges they are facing in processing their resources. I also hope that some will accept an offer to visit our facilities in Brisbane, Australia and see at first hand what we have to offer.