Effect of H₂ and CO contents in syngas during combustion using Micro Gas Turbine

Synthetic gas or syngas is produced from the gasification process. Its main compositions are hydrogen, H₂; carbon monoxide, CO; methane, CH₄; carbon dioxide, CO₂ and nitrogen, N₂. Syngas is a substitute for the depleting natural gas (80-90%.vol. CH₄). Natural gas is combusted in gas turbine in gas-fired power plant to produce electricity. However, combustion of syngas using gas turbine is expected to show different behavior compared to natural gas combustion. This is because of H₂ and CO contents in syngas have higher adiabatic flame temperature than CH₄. In this study, different quality of syngas with different contents of H₂ (0.6-0.8 %.vol.) and CO (1-3 %.vol.) were combusted using 30kW Micro Gas Turbine (MGT). Performances of different syngas quality were studied using NO_x, CO, CO₂ emissions and combustion efficiency parameters. NO_x and CO are the main pollutants from the combustion process. NO_x emissions were the highest for syngas with H₂ contents of 0.8 %.vol. and CO contents of 3 %.vol. CO emissions were in the range of 220-310 ppm for all the tested syngas. While, CO₂ emissions were in the range of 0.96-1.06 % for all the tested syngas. Combustion efficiencies were reduced for syngas with CO contents of 1 %.vol. and H₂ contents of 0.6-0.8 %.vol. This is most probably due to the dilution effect of N₂ in syngas.