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

Abstract

Synthetic gas or syngas is produced from the gasification process. Its main compositions are hydrogen, H2; carbon monoxide, CO; methane, CH4; carbon dioxide, CO2and 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 NOx, CO, CO2 emissions and combustion efficiency parameters. NOx and CO are the main pollutants from the combustion process. NOx emissions were the highest for syngas with H2contents 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 N2in syngas.