tailieunhanh - Advances in Gas Turbine Technology Part 10

Tham khảo tài liệu 'advances in gas turbine technology part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 260 Advances in Gas Turbine Technology nitrogen dilution in the fuel-rich region affected the reduction characteristics of NH3 the increase in nitrogen dilution raised the conversion rates of NH3 to NOx. This tendency showed the same as that of the case where nitrogenous compounds in fuel increased indicated by Sarofim et al. 1975 Kato et al. 1976 and Takagi et al. 1977 . That is it is necessary that the nitrogen bypassing technique is expected to improve fuel-NOx reduction in the cases of higher concentration of NH3. Test results Supplied fuels into the combustor were adjusted as same propertied as that of the slurryfeed coal gasified fuel. In tests the effects of the CH4 concentrations etc. in the supplied fuels on the combustion characteristics were investigated and the combustor s performances were predicted in the typical commercial operations. Figure 20 estimates the combustion emission characteristics under the simulated operational conditions of 1773K-class gas turbine for IGCC in the case where gasified fuel contains percent CH4 and 500ppm NH3. Total NOx emissions were surmised as low as 34ppm corrected at 16 percent O2 in the range where the gas turbine load was 25 percent or higher which is the single fuel firing of gasified fuel while the NOx emissions tend to increase slightly with the rise in the gas turbine load. In the tests of the simulated fuel that contained no NH3 thermal-NOx emissions were as low as 8ppm corrected at 16 percent O2 . On the other hand we can expect that combustion efficiency is around 100 percent under operational conditions of the medium-Btu fueled gas turbine. Fig. 20. Combustion emission characteristics 4. Conclusion Based on basic combustion test results using small burners and model combustors Japanese electric industries proposed the correspond combustion technologies for each gasified fuels designed combustors fitted with a suitable nitrogen injection nozzle two-stage combustion or lean combustion for each .