GreenFlame: Pollutant Emissions and Combustion Behavior of Low-CO2 Fuel Mixtures Based on Ammonia, Hydrogen, and Natural Gas
Industrial Collective Research (IGF), 1 December 2024 to 31 May 2027
Project description
The decarbonization of industry requires a long-term phase-out of fossil natural gas as an energy carrier. However, a comprehensive electrification of processes in thermal process engineering, metallurgy, and the basic materials industry is only possible to a limited extent.
Against this background, hydrogen, synthetic natural gas, and ammonia are being discussed as potential alternative fuels. Due to the fluctuating availability of these sustainable energy carriers, it is expected that during the transformation phase up to 2050 it will be largely unavoidable to use fuel mixtures that still contain fractions of fossil natural gas.
The combustion of such gas mixtures has so far been insufficiently investigated from a scientific perspective. Existing studies on technical flames at pilot-plant scale are scarce and often not directly comparable. At the same time, adequate experimental investigation and modelling are essential in order to describe sustainable thermal processes with regard to heat release, flame stability, and pollutant emissions (NOx).
Tasks of the IOB
Within the framework of this project, the Department for Industrial Furnaces and Heat Engineering (IOB) at RWTH Aachen University is assigned several essential tasks: In an initial phase, an existing test rig will be retrofitted for operation with ammonia. In addition to the development of a new safety concept, this includes, among other measures, the expansion of the gas supply system by an ammonia inlet line, a post-combustion chamber with the injection of air or ammonia, and a technical afterburning system as a safety measure to prevent ammonia slip.
In parallel, a numerical model based on a CAD representation of the test rig will be developed and optimized to investigate different approaches to combustion modelling and to implement a user-defined radiation model for high H₂O concentrations in the exhaust gas.
During the experimental studies, the ignition behaviour of various fuel compositions will be examined on a pre-competitive burner by means of cold-start tests, and a parametric study will be conducted to evaluate different measures for the reduction of nitrogen oxide emissions.
Finally, the results will be consolidated and analysed within a numerical simulation framework by modelling flow velocities, temperatures, and pollutant concentrations for different fuel compositions, thereby enabling optimization of the underlying reaction mechanisms.
Project goals
- Determination of fundamental parameters for binary and ternary fuel mixtures
- Design and development of new low-emission burner systems for these mixtures
- Development of detailed and reduced reaction mechanisms
- Investigation of the operating limits and stability of burner systems
- Identification of optimized parameters for primary measures to reduce NOₓ emissions of various burner systems
- Identification of new optimization potentials and emission reduction measures for burner systems in thermal process engineering
Project participants
Contact
Moritz Diewald, M.Sc.
Nicolas Dinsing, M.Sc.
Funding
The research project “GreenFlame” is funded by the Federal Ministry of Economic Affairs and Energy as part of the “Industrial Collective Research” programme on the basis of a resolution of the German Bundestag. This project 01IF23455N from the Research Association for steel Application (FOSTA), Düsseldorf, is carried out at the Department for Industrial Furnaces and Heat Engineering (IOB).