Low Carbon Reducing Agents Department
In Germany, the industrial sector emits the second-highest amount of greenhouse gases, exceeded only by the energy sector. Industrial processes, including those in the steel, cement, or aluminium industries, which currently use gas, coal, or graphite for applications such as reducing agents, electrode materials, or fuels, cannot be decarbonised through “mere” electrification. The technological gap and the long-term challenges lie in adapting industrial engineering processes to use alternative reducing agents, such as CO2-neutral hydrogen and CO2-neutral carbon. In addition, carbon capture and utilisation (CCU) can be used to capture and reuse unavoidable CO2 emissions.
The Department
With this in mind, the department of Low-Carbon Reducing Agents (LCR) investigates process technologies within the industrial sector, in order to avoid CO2 emissions by substituting carbonaceous raw materials as well as adapting existing engineering processes.
Many energy-intensive industrial processes involve subjecting solids to oxidising or reducing environments under high temperatures. The department has devised a methodology to develop alternative engineering processes using low-carbon energy carriers for such heterogenous systems. Empirical studies using pilot reactors and CFD simulations of gas-solid systems help us validate and subsequently scale up such processes to industrial levels.
Research and development topics of the LCR department include:
- Decarbonisation of steelmaking by using renewable hydrogen as a reducing agent
- Targeted insertion of biomass into the direct reduction process
- Reduction of iron oxides for further usage as metal fuels
- Retrofitting coal-fired power plants to burn metal fuels
- Carbon dioxide capture through conversion to graphite and hydrogen
The insights we gain during process development and adaptation further feed into the work of the department of Simulation and Virtual Design (SVD). Both increasing the efficiency of energy conversion and utilisation and the uptake of renewable energies can contribute step-by-step to a significant reduction in CO2 emissions.
Process-related CO2 emissions from the use of carbon-containing energy sources and other raw materials
Direct energy-related CO2-emissions from the use of fuels for the provision of energy, e.g., process heat or electricity (in industrial power plants) and indirect energy-related CO2- emissions from the upstream generation of the electricity used at the industrial site.
In general, these various sources of CO2-emissions require sector-specific approaches and measures for their reduction.
Therefore, the department Low Carbon Reducing Agents investigates options to avoid process-related CO2 emissions by adapting existing technologies as well as by substituting the emission-causing raw materials. Separation and subsequent use of CO2 (Carbon Capture and Utilization (CCU)) are examined in cases where CO2-emissions cannot be avoided.
In addition, the research results of the other two departments SVD and HTP of the Institute are incorporated into process development and adaptation. A significant reduction of energy-related CO2 emissions can be achieved by improving the efficiency of energy conversion and utilization, as well as by increasing the fraction of renewable energies used.
Research and development topics of the department Low Carbon Reducing Agents currently comprise:
Decarbonization of steel production using renewable “green” hydrogen as a reducing agent
CFD simulations to evaluate the achievable conversion rates with alternative reducing agents
Production of synthetic solid reducing agents from biomass, including CO2-neutral high-temperature heat from renewable electricity
Experimental verification at the component level on a laboratory scale
Emission reduction through the utilization of CO2 from coal-fired power plants for the production of synthesis gas, followed by further process steps yielding synthetic fuels and chemical base materials
Comparative techno-economic analysis of the decarbonization of industrial processes using gaseous and solid reducing agents
These topics are the department's challenges to assist energy-intensive industries in their quest for sustainable production and to provide suitable low-CO2 key-technologies as part of the energy transition.