|This is currently a time of great opportunity for brown coal developments in Australia. |
|Black coal, oil and gas prices are now consistently at levels that make new products derived from brown coal a viable proposition. |
Local manufacture of products such as fuels, fertilisers and fine chemicals from brown coal can help create new manufacturing industries, and deliver real long-term economic prosperity to the community. However environmental considerations, including the need to address the issue of CO2 emissions, mean that we will need an innovative approach to deliver this future.
In Victoria, the State and Commonwealth governments have put in place a number of policies and programs to stimulate new interest and investment in brown coal.
The Victorian Government recently announced an update on their coal allocation process, noting the local and international interest in Latrobe valley coals.
The Advanced Lignite Demonstration Program, announced in 2012, is seeking to encourage new technology demonstrations.
CarbonNet is building momentum, and looking at options for sequestration of the waste CO2, while Clean Coal Victoria is looking after coal resource planning.
BCIA has been working with government and industry to develop an R&D environment that supports developments in low-emissions coal technologies. BCIA funds a range of research projects, international linkages and skills development activities, as well as running programs for our industry members.
To boost the rapid adoption of new ideas, BCIA works with research groups in Australia and internationally to encourage development and implementation of research leading to a brighter future for brown coal.
For example, in March BCIA is sponsoring a collaborative workshop between Tsinghua University in China and Monash University in Melbourne to address carbon capture low-emissions coal developments.
BCIA also seek to build skills in the local research community, and assist in the training of the next-generation of professionals for the brown coal industry.
In the next month, BCIA will be running a workshop for early career researchers to help them optimise the chance of success for their projects; be that through high-quality publications to share their advances with a broad audience, or through progressing their projects more rapidly towards a commercial outcome. We were aiming for 20 participants, but numbers have doubled our expectations!
Closer to home, you may have noticed that BCIA now has a new address for our Melbourne office – we have moved to 1 Queens Road in Melbourne, and look forward to great views of the coming Australian Grand Prix which is taking place in Albert Park, directly opposite our new building.
RESEARCH AND DEVELOPMENT
|BCIA’s research portfolio supports the long-term, environmentally sustainable use of brown coal into a carbon-constrained future. Critical to this vision is the ability to utilise the coal and capture CO2 emissions for storage as efficiently and cost-effectively as possible. |
While there are many ways to achieve this, it is not clear which will be the best option for brown coal in terms of cost and suitability, so a range of different approaches are being investigated.
|For example, BCIA has funded a number of different projects looking at alternative ways to capture CO2 emissions (see page 2) and another on oxy-fuel combustion, which is a way to burn coal in oxygen to produce a concentrated stream of CO2 ready for compression and storage (see article in June 2012 Newsletter).|
|Another, very interesting strategy is chemical looping combustion, which is being investigated in a project led by Associate Professor Sankar Bhattacharya at Monash University. In general, chemical looping involves dividing a chemical reaction into two separate sub-processes, and in this context usually involves using a solid carrier to cycle metal oxides or CO2 scavengers between reactors. |
In the case of chemical looping combustion, the oxygen required for combustion is provided by a metal oxide. After reduction of the metal in the combustion reactor, the metal is recycled to an air-blown reactor where the metal oxide is regenerated.
By separating oxidation and combustion in this manner, chemical looping combustion allows the combustion of coal to occur in the absence of nitrogen, resulting in a flue gas that comprises mainly CO2 and water vapour. A highly-purified CO2 stream can easily be produced by cooling the exhaust gas and removing the condensed water.
There are two significant advantages to this approach.
Firstly, it allows for the combustion of coal in pure oxygen without the need for an expensive air separation unit, which is a major cost penalty in oxy-fuel combustion.
Secondly, it eliminates the cost and energy penalty of using a separate CO2 capture process. In principle, chemical looping combustion has the potential to substantially reduce the costs associated with sustainable production of electricity from brown coal.
The viability of the chemical looping combustion process depends on using an oxygen carrier that can be reused over a large number of combustion cycles, without significant loss of oxygen-carrying capacity. A/Prof Bhattacharya’s research team has been investigating a range of candidate materials, with an emphasis on low-cost materials such as iron-containing minerals, eg. hematite, ilmenite and limonite.
It is important to understand how the oxygen carrier interacts with the minerals in different brown coals, as well as the structural changes that occur with repeated use. The research program will also investigate the potential for the use of blended carriers to achieve more stable long-term performance.
Efficient, low-emissions combustion is only one of the ways that chemical looping could be used with brown coal. Other potential applications include (i) chemical looping gasification with pre-combustion capture of CO2, (ii) sorbent chemical looping for post-combustion capture of CO2 and (iii) chemical looping air separation for oxygen supply in oxy-fuel combustion or gasification.
Chemical looping technology is an active focus for research worldwide, and the technology is becoming increasingly sophisticated. We expect that A/Prof Bhattacharya’s project will lead to some exciting new possibilities for the sustainable use of Victorian brown coal.
|For more BCIA news, go to the next page of this e-newsletter.|