GAS TURBINES FIRED WITH BIOMASS PYROLYSIS SYNGAS: ANALYSIS OF THE OVERHEATING OF HOT GAS PATH COMPONENTS

Alternative resources such as biomass, and municipal and industrial waste arc being considered as a source for the production of syngas to replace natural gas as a power turbine fuel. Pyrolysis of biomass produces a syngas composed pnmarily of CO, CO2, CH4 and H-2 with a medium-low lower heating value (LHV) that is strongly dependent on the process boundary conditions such as the pyrolysis temperature and product residence time in the reactor [1, 2]. The issues associated with conventional gas turbines also apply to syngas turbines with the added complexity of the fuel and impurities. At present, syngas turbines are operated at firing temperatures similar to those of turbines fired on natural gas by increasing the fuel mass flow through the turbine. While this produces a higher turbine power output, the heat transferred to the hot flow-path vanes and blades is also greater. The aim of this paper is to report on the use of numerical modeling to analyze the fundamental impact of firing gas turbines with biomass pyrolysis syngas. To complete the analysis, the results have been compared with data from the literature on gas turbines fired with coal gasification syngas. The test engine used to perform this analysis is a General Electric GE10-2 gas turbine. The performance, aerodynamics and secondary flows were computed using proprietary software, while commercial finite element software was used to perform the thermal and local creep analyses.