The challenge
Metal production is fuelled by fossil fuel
Metal production, especially iron- and steel-making, contributes to about 10 per cent of global greenhouse gas emissions.
Currently, the industry heavily depends on coal to fuel its energy-intensive processes, including using coke as a reducing agent.
An increasing global focus on reducing carbon emissions, new regulatory frameworks, financial penalties and shareholder activism are putting pressure on metal producers to reduce their dependence on coal and coke.
Replacing a portion of the coal and coke used in metal production with charcoal can significantly reduce carbon dioxide emissions without substantially modifying the process. Charcoal is already used extensively for steel production in Brazil due to poor regional coal resources.
Charcoal is produced from the pyrolysis (high temperature decomposition) of organic material. For most countries, producing large volumes of charcoal using commercially available processes is too expensive because these processes require specific feedstock size and are limited in scale. This is a barrier to using charcoal in steelmaking.
The development of a more efficient pyrolysis technology capable of producing large volumes of charcoal from low-cost sustainable sources, such as wood wastes or forest residues, would overcome these barriers and is an essential step towards the widespread use of renewable carbon in metal production.
Our response
A new self-sustaining pyrolysis process
With the support of industry partners, we developed an innovative self-sustaining pyrolysis process to produce charcoal or 'designer biochar'. It can be made to meet the demands of specific applications involved in metal production.
Our self-sustaining slow pyrolysis process is auto-thermal, which means that material in the reactor is heated only by the heat of pyrolysis reactions and does not require additional heat in any form.
Our technology works in larger reactors and using a wider range of biomass feedstocks, which helps to lower production costs. The process also generates valuable by-products including bio-oil and bio-gas.
We have a pilot-scale facility capable of producing up to 1000 tonnes of charcoal per year, as well as recovering these by-products for further processing offline.
The results
Slashing the carbon emissions of metal production
Our auto-thermal pyrolysis process can produce large quantities of metallurgical-grade charcoal at a low cost for use in a wide range of industrial applications. It's an opportunity to substantially reduce global carbon emissions.
Charcoal is a renewable carbon source that can be substituted for high greenhouse-gas-emitting-fuels in virtually all high-temperature industrial processes in a relatively short timeframe.
For example, substituting 50 per cent of fossil carbon for charcoal in the steel industry alone would result in a two per cent reduction of industrial carbon dioxide emissions in Australia and a three per cent reduction in global carbon dioxide emissions.
In addition, the bio-oil and bio-gas by-products from the process can replace liquid and gaseous fossil fuels in this and other industrial processes to further reduce use of non-renewable and carbon-emitting resources.
This presents an opportunity to the steel-making industry to make high-end 'carbon lite' steel, which may offer a competitive edge against low cost importers.