Dresser Waukesha Rolls Out New Gen-Set: New 275GL+ engines offered for oilfield power generation configuration by amanda m. klemp
Dresser Waukesha has introduced a power generation configuration for its 275GL Series of gas engines. Packaged is the company’s Enginator gensets, the 275GL+ powered units are targeted at oilfield applications. The new power generation units are the latest additions to the 275GL Series, which was originally introduced in 2009 for gas compression.
The new gen-sets are offered with both the 16-cylinder 16V275GL+ and the 12-cylinder 12V275GL+ gas engines. The 16-cylinder version is rated 3480 kWe at 50 Hz and 1000 r/min and; at 60 Hz and 900 r/min, the unit is rated 3110 kWe. The 12-cylinder model has an output of 2600 kWe at 50 Hz and 2330 kWe at 60 Hz. In an Enginator gen-set configuration, the engine drives the generator through an elastic coupling. The switchgear, which is built and designed by Dresser Waukesha, is optional in the package. The engine is water cooled and the generator is air cooled.
The company incorporated its proprietary Engine System Manager (ESM) controls in the 275GL+ engines. ESM includes the central engine control unit, ignition, NOx modules, ignition coils and harnessing. For NOx levels, the company said both the 12V275GL+ and 16V275GL+ engines are capable of 0.5 g/bhphr NOx, 1.8 g/bhp-hr CO and 0.7 g/bhp-hr NMHC emissions levels without aftertreatment, which corresponds to 1/2 TA Luft NOx levels and meets the requirements for most nonattainment areas in the United States.
While the engines were originally introduced for gas compression applications, the move to power generation was fairly simple. “There are different requirements for a power generation engine versus a gas compression engine,” said Douglas Kiesling, director – design and analytical engineering at Dresser Waukesha. “Essentially, a power generation engine needs to run at a constant speed, while a gas compression engine runs at a constant load but at varying r/mins. “It’s a minimal effort to recalibrate the engine, but it is an essential change,” said Kiesling. He said a combination of changing the spark, altering fuel delivery and managing turbocharger wastegate and bypass calibrations prepared the engine to run at the constant speed and meet the engine speed requirements and limits for power generation.
The company said the engines are designed to run on low-quality gas pulled right from the ground and to operate at full power with heating values down to 23.6 MJ/m3 and at almost 70% load. In addition, the air intake and turbochargers are configured to allow operation at altitudes up to 1219 m and 914 m, for the 12-and 16-cylinder versions respectively, without de-rate.
“One of the things that is unique about running an engine on field gas is that the gas that comes right out of the ground is not the cleanest fuel. It has a lot of contaminant, lots of liquids and heavier carbon compounds that haven’t been removed,” Kiesling said. “So you need an engine that can quickly react to those changes in fuel quality, and the 275 engine is very good at that,” he explained. Fuel flexibility was achieved through a robust combustion process design, which includes fuel delivery, cylinder design, air handling and turbochargers. These elements are configured to handle a wide range of fuels and frequent swings in fuel quality.
Kiesling explained, “Achieving great er fuel flexibility requires widening the design parameters that affect combustion and matching them to a wider range of fuel qualities.” He said Dresser Waukesha targets specific design parameters to allow the most efficient combustion process for the varying fuel qualities. Though the 275 GL Series engines were targeted initially to gas compression applications, their fuel flexibility will allow them to work in any application with varying fuel qualities.