Biodiesel as an Alternative Fuel in Siemens Dry Low Emissions Combustors: Atmospheric and High Pressure Rig Testing

Abstract

Atmospheric and high pressure rig tests were conducted to investigate the feasibility of using biodiesel as an alternative fuel to power industrial gas turbines in one of the world’s leading dry low emissions (DLE) combustion systems, the SGT-100. At the same conditions, tests were also carried out for mineral diesel to provide reference information to evaluate biodiesel as an alternative fuel. In atmospheric pressure rig tests, the likelihood of the machine lighting was identified based on the measured probability of the ignition of a single combustor. Lean ignition and extinction limits at various air temperatures were also investigated with different air assist pressures. The ignition test results reveal that reliable ignition can be achieved with biodiesel across a range of air mass flow rates and air fuel ratios (AFRs). In high pressure rig tests, emissions and combustion dynamics were measured for various combustor air inlet pressures, temperatures, combustor wall pressure drops, and flame temperatures. These high pressure rig results show that biodiesel produced less NOx than mineral diesel. The test results indicate that the Siemens DLE combustion system can be adapted to use biodiesel as an alternative fuel without major modification.

Effect of Change in Fuel Compositions and Heating Value on Ignition and Performance for Siemens SGT-400 Dry Low Emission Combustion System

“…The increase of flame thickness can be seen in CO2 diluted flames: for a given equivalence ratio, the higher the dilution rate, the thicker the flame [15,16]. Weaker flameholding was also found by Liu et al [6,7] with bumer metal temperatures reducing as more diluent was added, and which also indicates the change in flame position and size [6,18,24]. Weaker flameholding was also found by Liu et al [6,7] with bumer metal temperatures reducing as more diluent was added, and which also indicates the change in flame position and size [6,18,24].…”

“…SITL DLE combustion technology is applied across the range of small-scale industrial gas turbines from 5MW to 15 MW (SGT-100 to SGT-400) [12,24,32]. The operational experience on these DLE engines has accumulated more than 20 x 10*h. Figure 1 shows the schematic view of the SITL DLE combustor.…”

“…This suppression effectively reduces the size of the O/H/OH radical pool [22] and suppresses the formation of NOx. Increased combustor pressure drop will enhance the air and fuel mixing by possible downstream displacement of the flame [24]. For industrial lean premixed system the unmixedness is a factor that can affect NOx.…”

Spray and combustion characteristics of biodiesel: Non-reacting and reacting

“…There have been reports from several groups that applied biomass-derived alternative fuel using liquid swirl flame burners (Hashimoto et al, 2008;Panchasara et al, 2009) and industrial gas turbines (Moli ere et al, 2007;Liu et al, 2009). Hashimoto et al (2008 reported lower NO x emission for palm biodiesel compared to diesel under gas turbine operating conditions.…”

“…The interest of applying biodiesel in gas turbine largely stems from the merits of renewability, sulphur-free and potentially cleaner combustion. However, due to differences in quality of biodiesel depending on feedstock, rigorous testing have to be performed to characterise the spray, combustion and emission performance to ensure the suitability and reliability of biodiesel in gas turbine.There have been reports from several groups that applied biomass-derived alternative fuel using liquid swirl flame burners (Hashimoto et al, 2008;Panchasara et al, 2009) and industrial gas turbines (Moli ere et al, 2007;Liu et al, 2009). Hashimoto et al (2008 reported lower NO x emission for palm biodiesel compared to diesel under gas turbine operating conditions.…”