The issue of emissions from mining-related activities has never been more topical. With the growing awareness of climate change governments are increasingly interventionist in the area and carbon-trading schemes are proliferating worldwide.
It's fertile ground for change, and mining companies themselves do not seem to mind, especially seeing as they will be the first to say that anything that reduces emissions is good for a company's reputation.
But with a 2005 study showing that more than 1.5 billion tonnes of greenhouse gases are being emitted from metal production alone, there's plenty of scope for improvement. Australia's premier scientific body, the Commonwealth Scientific and Industrial Research Organisation (CSIRO), is at the forefront of delivering that improvement.
Dr Sharif Jahanshahi leads the CSIRO's sustainable processing efforts through the Minerals Down Under National Research Flagship.
"Our sustainability theme aims to develop and demonstrate some breakthrough technologies that will minimise waste and emissions from the mineral industry, while improving their business performance and meeting the community expectation," he says.
"It is a triple bottom-line goal."
The CSIRO's brief is to assist relevant Australian industries in developing improved practices and technologies for reducing their environmental footprint while remaining technically and commercially competitive, hence securing their 'social licence to operate'. The growing acceptance by mining companies of the need for sustainability has been a key driver for increased collaboration between science and business.
"It was very clear to us that sustainability goes beyond any discipline and business, therefore solutions to complex environmental problems could only be found through a multi-disciplinary approach that goes across a number of business boundaries," Jahanshahi says.
Developments in emission reduction
Jahanshahi outlines a number of different approaches to reduce emissions from mining. The largest emissions issues occur in the production of the metals from their respective ores and this is the area that is receiving the greatest attention.
"Two of our key projects are being carried out in partnership with the Australian steel industry," he explains.
"Firstly, the recovery and reuse of high-grade waste heat from metallurgical slags through dry granulation. Secondly, the use of biomass derived charcoal as fuel and reductant in iron and steel industry."
Both of the projects – run in collaboration with the Cooperative Research Centre for Sustainable Resource Processing – have the aim of reducing the significant greenhouse gas emissions from iron and steel production.
The projects have now evolved beyond concept development to the pilot stage.
"Both OneSteel and BlueScope Steel are engaged in these projects and have provided significant financial support over the past two years," Jahanshahi says.
"We expect to take these projects from pilot scale into plant trials in Australia over the next year or two. The work done to date has assessed the technical, environmental and economical benefits of the new technologies and the case looks attractive. With the introduction of carbon trading schemes, we expect the economic case to become
A specific collaborative research project with the CRC for Plant-Based Management of Dryland Salinity has assessed the promise of plantation Mallee trees and conversion of biomass to char for use in lieu of coke and coal, particularly in processes like bath smelting, zinc slag fuming and reduction of minerals.
A matter of commitment
For the work done to be widely utilised, a high level of stakeholder engagement is essential and the mining industry plays a key role in that respect. Jahanshahi cites some promising options:
"An example of this is a plantation of short cycle Mallee trees to address the salinity affected regions and a sustainable source of biomass; then pyrolysis (chemical decomposition of organic materials by heating in the absence of oxygen) of the biomass to produce charcoal and bio-oil; the use of that charcoal by the metallurgical industry as substitute for coal to produce 'green steel' and the use of by-product slag from the smelting process as ‘green cement’. We are looking at using industrial ecology to address a few environmental problems, including carbon neutral metal production."
A decade ago the concept of carbon-neutral metal production was unheard of outside of scientific circles but now industry is partnering with science to achieve just that.
Fast work in the sustainable sector
The speed and quality of the work being done in sustainable processing is driving engagement by the business sector.
"In particular, the section of the industry that produces the high tonnage of materials to satisfy the society need," Jahanshahi says.
"The need will grow at a faster rate as the carbon trading scheme is introduced and value/cost of emission increases."
He confirms that the CSIRO's work follows the proven approach of concept development, evaluation of new concepts, demonstration and commercialisation. The earlier stages take at least a year, evaluation and industry engagement taking up to a further three years and then another three years or so before commercialisation begins. However, the work undertaken to date seems promising.
"In a couple of our projects we have managed to fast track the early stages and expect to move from laboratory-scale / pilot-scale to full-scale plant trials within a few years," says Jahanshahi.
"Construction and commissioning of demonstration plants will follow this and we could be looking at commercialisation of technology in four to five years."
A four-year timeframe from development to commercialisation for such a fundamental change to mining operations is indicative of the shift in thinking by both business and science, with both increasingly aware of the need for close collaboration.
The CSIRO's work is far from an Australia-only effort, with ever-improving coordination and collaboration at an international level
"The International Iron & Steel Institute (IISI) initiated their CO2 Breakthrough Program a few years ago with members from a large number of counties in Europe, Asia, North and South America," Jahanshahi says.
"The projects that we are doing at CSIRO in collaboration with the Australian steel industry (BlueScope Steel and OneSteel) are now included in the IISI portfolio of the projects. Both projects have attracted significant interest from overseas and we are looking into broadening our collaborative network through the Cooperative Research Centre for Sustainable Resource Processing."
There is likely to be growing collaboration between government, business and science given the growing international consensus around climate change, with carbon-trading schemes the glue.
Peak science bodies such as the CSIRO have years of work under their belts with sustainable processing and this work is getting attention from business because the need for improved environmental credentials can be assisted by processes that may even enhance profitability in a looming carbon trading environment. There aren't many win-win situations in business and science but with a full level of engagement from both sectors this may truly be one of those situations.