Clean Coal Combustion: Burning Issues of Syngas Burning

Coal-fired generation accounts for 82% of China's total power supply. Even in the UK the coal-fired generation still accounts for 35% . Because of this, the efficient and clean burn of coal is of great importance to the energy sector. Coal gasification and the proper treatment of the generated syngas before the combustion can reduce emissions significantly through alternative power generation system such as Integrated Gasification Combined Cycle (IGCC). The syngas usually contains varying amounts of hydrogen. The existence of hydrogen in the syngas may cause undesirable flame flashback phenomenon, in which the flame propagates into the burner. The fast flame propagation speed of hydrogen can travel further upstream and even attached to the wall of the combustor. The strong heat transfer to the wall may damage the combustor components. The consequence can be very costly. Because of this, many existing combustors are not suitable for the burning of syngas. To overcome this bottle neck, in-depth knowledge of the flame dynamics of hydrogen enriched fuel is essential, which is still not available. There is also a need to study the flame-wall interactions, which are important to the life span of a combustor but have not been fully understood.In order to understand the complex combustion process of hydrogen enriched fuels, combined efforts from experimentation and numerical simulations are essential. This joint project will investigate the flame dynamics including the flame flashback phenomenon, combustion instability, and flame-wall interactions. The flame dynamics will be investigated for different types of burners with fuel variability. Due to the limitation of optical access, the flame measurements need to be complimented by high-fidelity numerical simulations. The dynamic behaviour of the flame will be experimentally captured by the innovative combustion diagnostic tools developed at Manchester. To complement the experimental work, advanced numerical simulations based on direct numerical simulation and large eddy simulation will be performed at Brunel. The proposed research activities are based on the existing tools developed by the investigators and preliminary studies that have already been carried out by the applicants. The project will further develop innovative combustion diagnostic and advanced numerical tools. The knowledge to be gained from the project research and the physical models to be developed including improved near-wall flow, heat transfer and combustion models can lead to better combustion control and combustor design. The joint project will enhance the understanding on combustion of hydrogen enriched fuels with scientific advancement in flame measurements and near-wall flow modelling. More importantly, it will enhance the development of technologies for clean combustion of hydrogen enriched fuels, leading to a clean coal industry.Collaboration This project has excellent synergy between the UK and Chinese partners. Both partners are linked to BP. The Manchester group is directly supported by BP AE to work on combustion instability. Tsinghua University is one of the few identified links of BP in China. The involvement of Siemens Industrial Turbomachinery Ltd will ensure the maximum input from a gas turbine manufacturer's point of view.Management Both partners have long term informal research connections and the well established communications will ensure the smoothing running of the project. The PIs are well experienced in working with large research consortia. Dr Zhang has close collaboration with the industrial partners.Novelty Valuable physical insight into the potentially damaging combustion phenomena of hydrogen enriched fuels such as syngas burning will be provided; Original combustion diagnostics will be developed; Advanced numerical simulations will be performed; Near-wall flow, heat transfer and combustion models for unsteady reacting flows will be developed.