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Integrated gasification combined cycles can incorporate pre-combustion carbon capture. High-H2 syngas produces high H2O levels after combustion, potentially accelerating gas turbine component damage. Determining materials systems' suitability for this novel environment requires exposures in representative environments. Thus, an existing 0.7 MW burner rig was modified to generate the combustion environment and incorporate a cascade of 15 air-cooled turbine blades. Computational fluid dynamic calculations using blade dimensions and flow requirements supported the cascade design and determined blade placement within the gas flow. Trials of the modified unit have shown that a simulated combusted H2-rich syngas composition was generated at gas temperatures ≤1440°C. A 1000 h exposure has been carried out with thermal barrier coated blades to demonstrate the operation of the unit. [ABSTRACT FROM AUTHOR]

Integrated gasification combined cycles can incorporate pre-combustion carbon capture. High-H2 syngas produces high H2O levels after combustion, potentially accelerating gas turbine component damage. Determining materials systems' suitability for this novel environment requires exposures in representative environments. Thus, an existing 0.7 MW burner rig was modified to generate the combustion environment and incorporate a cascade of 15 air-cooled turbine blades. Computational fluid dynamic calculations using blade dimensions and flow requirements supported the cascade design and determined blade placement within the gas flow. Trials of the modified unit have shown that a simulated combusted H2-rich syngas composition was generated at gas temperatures ≤1440°C. A 1000 h exposure has been carried out with thermal barrier coated blades to demonstrate the operation of the unit. [ABSTRACT FROM AUTHOR]

With the introduction of novel fuels, which may contain high levels of trace impurities including sulphur and alkali metals, industrial gas turbines are operating with increasingly corrosive combustion environments. To investigate the effect that this, coupled with the higher combustion gas temperatures needed to increase power plant efficiency, has on current state-of-the-art gas turbine component materials, three burner rig exposure tests have been run. The tests evaluated the effects of fly ash, gas moisture and gas temperatures on the alkali sulphate induced hot corrosion of CM247LC, Haynes 230, IN939 and IN728LC. Type I (sulphidation and internal damage), type II (pitting) and mixed mode hot corrosion were observed under different test conditions; however, the presence of fly ash appeared to reduce the levels of hot corrosion. CM247LC, with its high Al content improving oxidation resistance, showed less resistance to hot corrosion than the other, higher Cr content, alloys. [ABSTRACT FROM AUTHOR]

The requirements to supply increasing quantities of electricity and simultaneously to reduce the environmental impact of its production are currently major issues for the power generation industry. Routes to meeting these challenges include the development and use of power plants with ever increasing efficiencies coupled with the use of both a wider range of fuels and technologies designed to minimise CO2 emissions. For fireside hot gas path components, issues of concern include deposition, erosion and corrosion in novel operating environments and increased operating temperatures. The novel operating environments will be produced both by the use of new fuel mixes and by the development of more complex gas pathways (e.g. in various oxyfired or gasification systems). Higher rates of deposition could significantly reduce heat transfer and increase the need for component cleaning. However, degradation of component surfaces has the potential to be life limiting, and so such effects need to be minimised. Materials and operational issues related to these objectives are reviewed. [ABSTRACT FROM AUTHOR]