The ALSTOM GT13E2 Medium BTU Gas Turbine

ALSTOM Power’s GT13E2 gas turbine has been successfully commissioned in a refinery residual oil gasification process (api Energia, Italy) operating on Medium Btu gas (GT13E2-MBtu). The modification of the standard GT13E2 to operate with MBtu fuel has resulted in an improvement in the performance of the GT13E2 to exceed 192 MW and 38% efficiency (simple cycle) at ISO conditions. The GT compressor has been upgraded to incorporate an extra-end stage to boost the pressure ratio to 17:1 and improve performance. Syngas from residual oil gasification has a typical volumetric composition of 45% H2 , 48% CO and 7% CO2 and a lower heating value of 13.9 MJ/kg. This syngas has been diluted with N2 to reduce the heating value to 7 MJ/kg lowering reactivity and allowing partially premixed operation. In order to operate with syngas a redesign of the standard EV burners was necessary to deal with the associated high flame velocities and volume fluxes. The fuel injection for syngas operation was placed at the burner end and the gas injected radially inward to obtain inherently safe operation. The gas turbine demonstrated successful operation with both syngas and oil No. 2 fuels. At the standard dilution of 7MJ/kg NOx emissions are in the 20–25 vppm range and the CO emissions are below 5 vppm independent of load. The modified burners demonstrated safe operation on syngas with and without dilution of nitrogen in a tested LHV range from 6.8 to 14 MJ/kg. This behavior allows high flexibility of the entire power plant. Changeover from oil no. 2 to syngas and vice versa can be done between 50 and 100% load. The gas turbine components have been inspected several times during the commissioning period and shown to be in good condition.Copyright © 2002 by ASME