Intelligent chemistry for mining: BASF invests in R&D

As new finds decline, the mining industry is looking to chemical companies to maximise the value of low-grade deposits. Julian Turner talks to David Timms, BASF's business director for performance chemicals Australia & New Zealand, and Dr John Farrow of the Australian Mineral Research Centre, about pushing the boundaries of intelligent chemistry for mining.

The phone connection between London and BASF's sub-regional headquarters 10,000 miles away in Melbourne may have lacked clarity, but the message delivered by David Timms, the company's business director for performance chemicals Australia & New Zealand, resonated loud and clear: BASF's new global R&D and technology centre in Perth is a major step on the road to establishing the German industrial giant as the leading chemical solutions provider and innovations partner to the global mining industry.

As mining companies enter ever more inhospitable environments in search of ever-decreasing mineral reserves, investments like BASF's new facility will help develop and bring to market new technologies that can successfully extract valuables from lower-value ores.

"The innovations we develop will be adopted by our mining businesses worldwide."

"The likelihood of finding a major high-grade pristine ore deposit is very low," said Dr John Farrow, CSIRO site manager of the Australian Minerals Research Centre, which will house BASF's new facility. "What the industry must focus on is processing lower grade materials, but unfortunately many of these ores are very complex in terms of their mineralogy and associated impurities.

"You may find a gold deposit that has two or three parts per million of gold but it can have other associated minerals that make processing that gold impossible. It's not unheard of these days for operators to try to process 0.8 parts per million of gold; that's 0.8 of a gram from a tonne of ore. If you go back 40 years, even the tailings often contained that much gold."

"Resource depletion is increasing significantly," confirmed Timms, "and with that comes the search for lower-grade ores in more remote areas. Chemical solutions that can get the minerals out of those ores are becoming a major focus for the industry.

"The Perth R&D centre will be a global mining research hub for BASF and we have very ambitious plans for its growth. Mineral processing will be our core area and the innovations we develop there will be adopted by our mining businesses worldwide," Timms said.

Joint enterprise: collaborative research and market acquisitions

BASF gained a foothold in the global mining market via a trio of strategic acquisitions, beginning in 2006 with the purchase of Degussa's construction chemicals business - an expert in underground construction and tunnel-building - and then Ciba, a specialist in solid-liquid separation, in 2009. Cognis, a specialty chemicals company bringing in hydrometallurgy and extraction technologies, was snapped up the following year.

"The use of nitric acid has the potential to redefine the economics of nickel extraction from laterites."

Less than 18 months later, BASF is preparing for the next phase in its expansion plan. Since 1 January, a small team of researchers and developers has been working at the Australian Minerals Research Centre at Waterford in Perth, where it has leased laboratory space from the Commonwealth Scientific and Industrial Research Organisation (CSIRO).

BASF will also finance collaborative studies conducted by the world-renowned Parker Centre in the areas of breakthrough technologies and process fundamentals primarily focused on alumina, base metals (particularly cobalt, copper, nickel and zinc), gold and uranium.

Here, we investigate some of these techniques and assess their potential commercial and environmental impact.

Breakthrough technologies: in-situ leeching, nitric acid and thiosulfate

Through engagement with the Parker Centre, BASF will further develop its expertise in process fundamentals such as solid-liquid separation and solvent extraction, as well as have the opportunity to take advantage of leading-edge research into breakthrough technologies such as in-situ leaching (ISL). Also called in-situ recovery (ISR) or solution mining, it is increasingly being used to recover valuables such as copper and uranium without the need for costly, energy and labour-intensive processes such as drill-and-blast, open-cut or underground mining. The process involves injecting environmentally benign solutions into the deposit and then pumping out the solution bearing the dissolved valuable metals.

"In situ leaching is clearly a technology of the future," says Farrow. "In this regard, we are doing a lot of developmental work using a reagent called thiosulfate, which has the prospect of replacing cyanide as an in situ lixiviant for taking gold out of the host rock and bringing it to the surface.

"Another breakthrough technology under development is in the area of nickel. A company called Direct Nickel has come up with the idea of using nitric acid to dissolve nickel laterites, precipitating out the aluminium, iron and other impurities and then recovering the nickel, cobalt and the other values from the solution. A mechanism is then used to recycle and reuse up to 98% of the nitric acid.

"We are currently establishing a one-tonne-per-day pilot facility to prove the concept at the next scale of operation. If this is successful, it will be a major breakthrough for the processing and production of nickel, and redefine the economics of nickel extraction from laterites."

The United Nations of metallurgy: the role of the Parker Centre

In order to take advantage of such innovations, BASF has signed a long-term agreement with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) to lease laboratory and office space at its Australian Minerals Research Centre at Waterford in Perth. Here, BASF will work with scientists from the Parker Centre, the world's leading hydrometallurgical research provider.

"Operators are trying to process 0.8 of a gram of gold from a ton of ore – 40 years ago, even the tailings often contained that much gold."

Industry funding for the centre, which was established in 1992 under the Australian Federal Government's Cooperative Research Centres (CRC) programme, totals $27.7 million since 2005. It has proved to be an inspired investment; according to an independent audit, the Parker Centre has generated an average net present value of $22 for each $1 of industry investment.

"The Parker Centre is the United Nations of hydrometallurgy, bringing together numerous parties with a common interest in advancing the science underpinning the range of hydrometallurgical processes used in the minerals industry," Farrow explains. "It also offers the opportunity for companies to work with the researchers on a confidential basis.

"For BASF, that may involve developing a new chemical that has great commercial potential. It's done as a confidential collaboration, with the intellectual property ownership determined according to the respective input from the researchers and the company, and accounting for commercial needs."

BASF innovations: Rheomax ETD and novel flocculant technology

BASF will the use the official R&D centre opening on 13 July to showcase innovations of its own. These include novel flocculant technology (NFT) and enhanced rheology modifiers. Used for thickening processes (or solid / liquid separation), NFT comprises chemistry (flocculants) as well as process application and process control. It increases the solid content of mud without adversely affecting its yield stress, maximising output capabilities and making the process more efficient.

Rheomax ETD (enhanced tailings disposal) rheology modifiers are designed to enhance the tailings management process. Depending on the required application, the technology can significantly increase both the stacking angle of the disposed solids and the capacity of existing impounds. It also offers the opportunity for a more effective co-disposal process by generating homogenised, stable, faster drying tailings that can be rehabilitated far earlier and more easily. Rheomax ETD rheology modifiers may also result in the faster release of cleaner liquor streams, minimising losses through evaporation.

"A lot of our innovation work is based around sustainability, energy reduction and water reuse and aimed at industries such as alumina and copper smelting operations," says Timms. "Much of BASF's work on rheology modifiers is to do with maximising water recovery and recycling and getting the maximum amount of reuse out of waste.

"Anything that can be done to improve energy efficiency will be of huge benefit to the industry."

BASF's capital and intellectual investment in intelligent chemistry for mining in Australia in general - and its new global R&D and technology centre in particular - strengthens the company's local R&D capabilities in proximity to industrial research centres and global key customers in the burgeoning Asia-Pacific market. As importantly, it is a major boost to the global mining industry as it strives to improve its processing efficiency and financial bottom line.