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China's slowing economy, has in turn, reduced the demand for commodities such as iron ore – and China is Australia's most important market. At the same time, Australia's supply of high grade ore is being depleted, while resource-rich Brazil is ready to step up and dominate the high grade iron ore market.
This is the challenge facing Australian exporters. Effectively, it is how to replace naturally high grade iron ore exports with alternative products that meet the needs of international buyers.
Considerations include the cost of processing, the quality of the resultant product and the environmental impacts. Smelting lower grade ores requires more energy, which adds to the financial costs and increases environmental emissions associated with the process.
Capturing Australia's comparative advantage
Fortunately, Australian iron ore exporters have some advantages.
One is geographical – being closer to Asian markets reduces the cost of shipping, which is significant when one purchase can involve millions of tonnes.
The second is access to the expertise and resources of Australia's national science agency. CSIRO has a team of specialists who can develop product testing research programs to address key challenges faced by iron ore producers.
Working with Australian mining companies, CSIRO is providing material analysis that gives valuable information on ore quality.
This information enables exporters to modify their ore blends to suit steelmaker needs, along with valuable information to inform decisions around the most cost-effective and environmentally-friendly processing methods. It can also help producers decide whether a deposit is currently worth extracting, or best left in the ground.
Supporting industry to upgrade raw material
According to Keith Vining who leads CSIRO's iron ore and carbon steel research, there are two main ways that they assist mining companies.
"One is to look at the potential for upgrading the material," Dr Vining says.
"So, for instance, removing the deleterious elements, assessing whether material has the potential to be upgraded or figuring out an appropriate way to do that, as well as how to achieve that upgrade for the minimum cost possible."
Dr Vining explains that typically, the materials that dilute the ore are silica and alumina. These are the impurities that cause processing difficulties downstream, so buyers focus on them and put cost penalties on the ore.
The CSIRO team looks for ways to cost-effectively reduce, or remove, the silica and alumina, which then leads to an improvement in the iron grade.
Another method to upgrade lower grade deposits of materials, such as magnetite and hematite – which usually contain around 30 per cent iron – is to grind them to a fine powder from which it is then relatively easy to separate the iron and produce a high grade product.
"While it's not an asset that we've traditionally relied on very heavily because of the processing costs, calculating grinding costs and determining the metallurgical properties of the resulting product, is helping to shift the thinking to put more emphasis on magnetite concentrates," Dr Vining says.
"It's making people consider whether now is the right time to begin exploiting these resources."
Understanding texture to determine value-in-use
If reduction or removal of unwanted materials is not practical, the CSIRO team has a second strategy.
"If you can't get it out, well, let's find a way that we can effectively use it. These are technical marketing activities to establish the real value-in-use of the material."
In practice, this involves looking beyond the chemical composition of a sample to its structure – the way in which the elements and minerals are linked or positioned.
"With this information, we can show that an ore with an unimpressive sounding chemical composition, but a beneficial structure, can deliver processing advantages to the end user," Dr Vining says.
"That's an important factor that can influence saleability and other decisions, such as whether or not to mine the deposit."
The key to being able to analyse and treat ore samples and determine the effect of the composition on their processing is CSIRO's world-class pilot processing plant. The plant batch processes ore samples of as little as one to two tonnes, and can replicate a traditional continuous process.
"We work at a scale where we can use international standards to establish the quality of the material, which is exactly what the end customers would use to measure in a continuous large-scale process," Dr Vining says.
"So, our test results are directly applicable to the real world."
Leading end-to-end solutions
A major benefit of CSIRO's team is that they have end-to-end expertise. From strong ore characterisation capability, through to extensive beneficiation experience and pilot scale processing for determining the metallurgical properties of the materials.
In practice, this means the team can work with small samples from undeveloped resources to assist in determining their viability, through to helping inform their clients' investment decisions and sales process as they take their product to market.
When asked about the potential of the CSIRO team's approach, Dr Vining is enthusiastic.
"Personally, I believe the whole concept of textural ore classification is applicable across much of the mineral processing industry," he says.
"There's a lack of understanding from industry about the importance of ore texture on processing, so we need to educate the market that texture is an important factor to measure.
Doing so, can give a miner valuable information that can have significant impacts on operation costs."
And, looking to the future?
"Right now, we’re pretty busy working with the iron ore sector, but the next natural extension would be to look at similar opportunities with bauxite," Dr Vining says.
"I think we could add value to that industry too. It feels like the next logical step."