New High Power, Large Bore Gas Engine from MAN Diesel
MAN Diesel has announced a further extension of its line-up of four-stroke gas engines with the new 51/60G. The new engine like its 51/60DF dual fuel stable-mate is derived from MAN Diesel’s type 48/60 Diesel engine platform. The engine uses a distillate fuel pilot injection system to achieve reliable, stable ignition of lean air-gas mixtures in a large bore, open combustion chamber. As a result, the new gas engine is said to have one of the highest power densities in the four-stroke gas engine field as well as low emissions of oxides of nitrogen (NOx) and high fuel efficiency.
The 51/60G is offered in a nine-cylinder inline version and Vee configuration versions with 12-, 14-, and 18-cylinders. Standard rated outputs are 1000 kW per cylinder for 60 Hz power generation and 975 kW per cylinder for 50 Hz power generation. This overall power range from 8775 to 18 000 kW mechanical equates to nominal generator set outputs from 8538 kW to 17 514 kW electrical.
The 51/60G makes extensive use of microprocessor control technology to achieve its favorable economics and low emissions. Gas admission is controlled via electronically controlled, electrically actuated valves in the 51/60G’s inlet ports while pilot fuel injection is likewise via an electronically controlled, electrically actuated common rail system. Further enhancing both control of the air-fuel ratio and the efficiency of the 51/60G is the use of MAN Diesel’s VTA Variable Turbine Area turbocharger technology. The overall effect of these measures is specific consumption for natural gas plus the liquid fuel pilot of 7708 kJ/kWhe (7500 kJ/kWhm) for generator sets powered by the 51/60G in NOx optimized applications, and 7430 kJ/kWhe (7230 kJ/kWhm) in efficiency optimized applications. With NOx emissions levels below 500 mg /m³ at 5% O2, the 51/60G both readily achieves compliance with the limits prescribed in Germany’s TA luft clean air code and undercuts the limits currently required by the World Bank by a wide margin, according to MAN.
“Naturally, we expect the 51/60G to be popular in co-generation and trigeneration applications,” said Dr. Stephan Mey, head of MAN Diesel’s Augsburg based Power Plant business unit. “In these plants, thermal energy recovered from engine sources is used for heating, cooling or generating process steam, resulting in energy utilization levels as high as 95%. As with our large diesel engines, a further energy recovery option on offer from MAN Diesel with the 51/60G is a combined cycle set-up in which the exhaust heat of the 51/60G engine is used to produce steam to drive a steam turbine generator. In this way, the overall electrical output and efficiency of the power plant can be increased by 10% to 15% without additional fuel costs.”
For more information: www.mandiesel.com