IGCC: Understanding gasification processes

The reaction kinetics in gasifiers form a focus of the “High-temperature gasification and gas purification” project, called HotVeGas for short. With gasification, the processes occur at least 20 times more slowly than with combustion. However, little is still known about the actual speed of the reactions and how the different fuels behave. Therefore, with the help of optical measurements and experiments, the researchers are developing simulations that shed light on the processes in gasifiers.

The focus of the investigation is on the conversion of the fuel in the gasifier. This process substantially determines the efficiency of the system.

The aim of the project is to provide the participating manufacturers with simulation models that will enable them to gain a greater understanding of the processes in gasifiers. This knowledge will then enable them to optimise their products.

Entrained-flow gasifiers are compact

The research is focussing on entrained-flow gasifiers as a type of possible gasifier. "This is currently the most economically efficient technology for gasifying coal in large-scale plants," explains Professor Hartmut Spliethoff from the Institute for Energy Systems at the Technische Universität München. Entrained-flow gasifiers are also very compact in power plants with a 500 MW output.

The combination of processes increases the efficiency

The aim of the research project is to provide the basis for the long-term development of highly efficient high-temperature gasification processes with integrated hot gas purification and optimal CO2 separation for IGCC power plants. In particular, the researchers are investigating processes for manufacturing synthetic fuels such as hydrogen, methane, methanol and other liquid fuels.

This is because the coupling of different processes produces synergy effects. One example is the production of hydrogen as the basis for fuels. "This results in considerably greater efficiency rates in the combined process," reports Spliethoff. For instance, the oxygen from the electrolysis can be recycled and the carbon monoxide from the gasifier can be completely used for the methanation.

The research consortium is being funded by the German Federal Ministry of Economics and Technology as part of its COORETEC programme.