The steel industry is ready to meet the global challenge of climate change by reducing energy and emission intensity across the industry.
The industry has access to technologies to manage most common emissions (SOx, NOx, dust, heavy metals) that can meet increasingly stringent regulatory requirements.
Mitigation of CO2 emissions still elude the industry, as the chemical process of converting iron ore to metallic iron requires carbon as a reducing agent, and to provide energy to generate the extreme temperatures needed for the reaction to occur. The blast furnace process has been improved over the past decades and, with the introduction of smart or intelligent manufacturing, it will become even more efficient.
The challenge is being pursued on four fronts:
- Ensuring the raw materials used in the iron making process or hot metal production is of a level of quality that minimises its use (iron ore, coking coal) and maximises resource efficiency.
- Transfer of best practice performance across the industry to reduce the energy intensity of the steelmaking process as this affects CO2 emissions. Energy intensity can be influenced by many factors, which are manageable, as many organisations have proven.
The chart shows typical operating site reliability performance with the best-operating plants near the reference level.
- Implementation of industry 4.0, smart or intelligent manufacturing as early as possible for the most energy-intensive processes. Evidence shows that smart control systems reduce variation making the process stable and efficient. This will be the case for any process. The priority is to introduce this in the most energy-intensive areas to industry 4.0 as soon as practical to have the biggest impact.
- Investment in breakthrough technology needs to increase significantly to achieve the tight timeline for the CO2 emission reduction needed. Recent breakthrough programmes and technologies include ULCOS, which led to the HIsarna process in Europe, COURSE50 in Japan, the American Iron and Steel Institute programme in the US, and company-specific investments by POSCO in South Korea, China Steel Corporation in Taiwan, China, and Baowu in mainland China.Two recent projects using hydrogen as the reducing agent instead of carbon have been launched and show promise (HYBRIT in Sweden by SSAB and partners, H2FUTURE in Austria by voestalpine and partners). The reduction reaction is rapid and it requires more energy to create the heat (1300 – 1500°C) as well as generate the hydrogen. This means the energy (electricity) for the heat and hydrogen generation must be carbon-free for it to be effective in reducing CO2 intensity in steelmaking.
All the above contribute to meeting the challenge of climate change towards the 2°C scenario.
To progress the research and development for breakthrough technology, significant funding is required to support the research teams, and this cannot be supported by industry alone. Government and regional financial support (especially cross-border collaborative government support) will be needed for effective progress to be made.
In the interim, carbon capture utilisation and storage (CCUS) and carbon capture and storage (CCS) technologies will be required to store or use CO2 in other applications if society wishes to reach the 2°C scenario. These two processes will be needed until more radical breakthrough technologies become available.