CIMAC Congress - Schiff & Hafen

Tuesday, 15 June
Monday 14 June
operational fuel. This paper describes the technology of efficiency
enhancement and the features of these new engines, including test
results performed at the factory and at actual sites. Working in
collaboration with the New Energy and Industrial Technology
Development Organization (NEDO) and the Japan Gas Association
(JGA), MHI has completed advanced development of technology to
improve the efficiency of gas engine. These improvements are focused
on the optimization and control of combustion. Using these
technologies, the MACHII-SI has optimized its exhaust temperature
and consequently reached a total efficiency of 66% - combined with
generation efficiency and steam efficiency, the world’s highest for this
class of engine. These same enhancement technologies have also been
applied to the former MACH-30G model raising its power generation
efficiency up to 46%. Moreover, the MACHII-SI start-up time has
been reduced to less than six minutes from activation to 100%
loading, meeting the requirements for peak application. Intricate
details combining optimum control and the diagnosis techniques for
combustion greatly contribute to this performance achievement. We
have been conducting rigorous verification tests for start-up,
performance, reliability, and overall system operation under the most
severe conditions at our in-house test plant since October 2008. With
the CM-MACH, low calorie gas has been achieved by means of gas
supply features in both the intake port at each cylinder and the suction
port before the turbocharger. This feature offers an additional safety
advantage in that it keeps an appropriate concentration of air-fuel
mixture in the intake system to prevent auto ignition. The first engine
was delivered and began operation in October of 2009.
MHI believes that through our expanded lineup of MACH gas engines,
we are able to meet an unprecedented diversity of customer needs.
Development of large gas engine with high
efficiency (MD36G)
T. Oka, M. Kondo, Mitsui Engineering and
Shipbuilding Co. Ltd., Japan,
T. Aiko, Daihatsu Diesel MFG. Co., Ltd., Japan
Mitsui Engineering & Shipbuilding Co., Ltd. (MES) has developed
a large size lean-burn gas engine MD36G with high efficiency
whose generating power output range is 2.8 - 8.1MW jointly with
Daihatsu Diesel MFG. Co., Ltd. (Daihatsu) and opened business in
April 2008. The base engine of MD36G is the medium-speed diesel
engine Daihatsu DK-36 that has a large number of records and
experiences in both land and marine engines. The engine has been
developed as a series of a 1MW class as engine MD20G which had
already been developed and commercialized by MES, in line with a
trend of market demand for bigger generator engines. Basic concept
of MD20G has been followed, and experiences and know-how
obtained from operation results of MD20G have been incorporated
into development. Technologies such as the Miller cycle and
combustion control in addition to the direct-injection micro pilot
ignition which is the most significant feature of the MD-G series,
are applied to the MD36G. It is possible to cope with various usages
flexibly, because the electronic control units that have abnormal
combustion detection and air-fuel ratio control for stable
combustion are developed by MES.
The demonstration plant with this developed engine is working
well as a power generation facility in Tamano works of MES, and it
was confirmed through its operation we achieved the world top
class high generating efficiency among gas engines with same
output range at the mean effective pressure 2MPa. Regarding NOx
emission, 300ppm (O 2
=0%) NOx in the normal model and below
200ppm(O 2
=0%) NOx in the low NOx model of that cycle
parameters have been changed, has been confirmed.
As a result of this development, our lineup of gas engines whose
generating power output range is 0.88 ~ .1MW has been completed.