EXTENSION OF FUEL FLEXIBILITY IN THE SIEMENS DRY LOW EMISSIONS SGT-300-1S TO COVER A WOBBE INDEX RANGE OF 15 TO 49 MJ/m~3

摘要

The extension of gas fuel flexibility in the Siemens SGT-300 single shaft (SGT-300-1S) is reported in this paper. A successful development programme has increased the capability of the Siemens Industrial Turbomachinery, Lincoln (SITL) dry low emissions (DLE) burner confipration to a fuel range covering a Wobbe Index (WI) from 15 to 49 MJ/m~3.The standard SGT-300-1S SITL DLE combustion hardware allowed for gas and liquid fuels within a specified range typically associated with natural gas and diesel, respectively. Field operation of the standard production SGT-300-1S has confirmed the reliable operation with an extension to the fuels range to include processed land fill gas (PLG) from 32 to 49 MJ/m~3.The further extension of the fuel range for the SGT-300-1S SITL DLE combustion system was achieved through high pressure testing of a single combustion system at engine operating conditions. The rig facility allowed for the actual fuel type to be tested using a mixing plant. The variations in fuel heating value were achieved by blending natural gas with diluent CO_2 and/or N_2. Various diagnostics were used to assess the performance of the combustion system including measurement of combustion dynamics, temperature, fuel supply pressure and emissions of NOx, CO and unburned hydrocarbon (UHC).The results of the testing showed that the standard production burner can operate for a fuel with WI as low as 23 MJ/m3 which corresponds to 35% CO_2 (in volume) in the fuel. This range can be extended to 15 MJ/m~3 (54.5% CO_2 in the fuel) with only minor modification, to control losses through the burner and to maintain similar fuel injection characteristics.The SITL DLE combustion system is able to cover a WI range of 15 to 49 MJ/m~3 in two configurations. The results of testing showed a lowering in WI, from diluting with CO_2 and/or N_2, a benefit in NOx reduction is observed. This decrease in WI may lead to an increased requirement in fuel supply pressure.