The need for reductions of nitrogen oxides (NOx), sulfur oxides (SOx), and carbon dioxide (CO2) emissions has been acknowledged on the global level. However, it is difficult to meet the strengthened emissions regulations by using the conventional marine diesel engines. Therefore, lean burn gas engines have been recently attracting attention in the maritime industry. Because they use natural gas as fuel and can simultaneously reduce both NOx and CO2 emissions. On the other hand, since methane is the main component of natural gas, the slipped methane, which is the unburned methane emitted from the lean burn gas engines, might have a potential impact on global warming. The authors have proposed a combined exhaust gas recirculation (C-EGR) system to reduce the slipped methane from the gas engines and NOx from marine diesel engines by providing the exhaust gas from lean burn gas engine to the intake manifold of the marine diesel engine using a blower. Since the exhaust gas from the gas engine includes slipped methane, this system could reduce both the NOx from the marine diesel engine and the slipped methane from the lean burn gas engine simultaneously. This paper introduces the details of the proposed C-EGR system and presents the experimental results of emissions characteristics on the C-EGR system. As a result, it was confirmed that the C-EGR system attained more than 75% reduction of the slipped methane in the intake gas. Additionally, the NOx emission from the diesel engine decreased with the effect of the exhaust gas recirculation (EGR) system.

References

References
1.
IMO, 2017, “
International Convention for the Prevention of Pollution From Ships (MARPOL)
,” International Maritime Organization, London, accessed Sept.15, 2017, http://www.imo.org/en/about/conventions/listofconventions/pages/international-convention-for-the-prevention-of-pollution-from-ships-(marpol).aspx
2.
Lin
,
C.-Y.
,
2013
, “
Strategies for Promoting Biodiesel Use in Marine Vessels
,”
Mar. Policy
,
40
, pp.
84
90
.
3.
Brynolfa
,
S.
,
Magnusson
,
M.
,
Fridella
,
E.
, and
Andersson
,
K.
,
2014
, “
Compliance Possibilities for the Future ECA Regulations Through the Use of Abatement Technologies or Change of Fuels
,”
Transp. Res. Part D
,
28
, pp.
6
18
.
4.
Briggs
,
J.
, and
McCarney
,
J.
,
2013
, “
Field Experience of Marine Selective Catalytic Reduction
,” CIMAC Congress, Shanghai, China, May 13–16, Paper No. 220.
5.
Azzara
,
A.
,
Rutherford
,
D.
, and
Wang
,
H.
,
2014
, “
Feasibility of IMO Annex VI Tier III implementation Using Selective Catalytic Reduction
,” The International Council on Clean Transportation, Washington, DC, Working Paper
2014-4
.
6.
Herdzik
,
J.
,
2013
, “
Aspects of Using LNG as a Marine Fuel
,”
J. KONES
,
19
(
2
), pp.
201
209
.
7.
Einang
,
P. M.
,
2007
, “
Gas Fueled Ships
,” CIMAC Congress, Vienna, Austria, May 21–24, Paper No. 261.
8.
Nylund
,
I.
, and
Ott
,
M.
,
2013
, “
Development of a Dual Fuel Technology for Slow-Speed Engines
,” CIMAC Congress, Shanghai, China, May 13–16, Paper No. 284.
9.
Troberg
,
M.
,
Portin
,
K.
, and
Jarvi
,
A.
,
2013
, “
Update on Wärtsilä 4-Stroke Gas Product Development
,” CIMAC Congress, Shanghai, China, May 13–16, Paper No. 406.
10.
Juliussen
,
L. R.
,
Mayer
,
S.
, and
Kryger
,
M.
,
2013
, “
The MAN ME-GI Engine: From Initial System Considerations to Implementation and Performance Optimization
,” CIMAC Congress, Shanghai, China, May 13–16, Paper No. 424.
11.
CIMAC WG 17
,
2014
, “
Methane and Formaldehyde Emissions of Gas Engines
,” The International Council of Combustion Engines, Frankfurt, Germany, accessed Sept. 15, 2017, http://www.cimac.com/cms/upload/workinggroups/WG17/CIMAC_Position_Paper_WG17_Methane_and_Formaldehyde_Emissions_2014_04.pdf
12.
Tashima
,
H.
, and
Tsuru
,
D.
,
2013
, “
Reduction of Methane Slip From Gas Engines by O2 Concentration Control Using Gas Permeation Membrane
,”
SAE
Paper No. 2013-01-2618.
13.
May
,
I.
,
Cairns
,
A.
,
Zhao
,
H.
,
Pedrozo
,
V.
,
Wong
,
H. C.
,
Whelan
,
S.
, and
Bennicke
,
P.
,
2015
, “
Reduction of Methane Slip Using Premixed Micro Pilot Combustion in a Heavy-Duty Natural Gas-Diesel Engine
,”
SAE
Paper No. 2015-01-1798.
14.
Yoo
,
D.-H.
,
Fujita
,
H.
, and
Harano
,
W.
,
2009
, “
Exhaust Gas Recirculation in Combined System of Gas Engine and Diesel Engine
,”
J. Jpn. Inst. Mar. Eng.
,
44
(
1
), pp.
145
149
(in Japanese).
15.
Nitta
,
Y.
,
Yoo
,
D.-H.
,
Nishio
,
S.
,
Ichikawa
,
Y.
, and
Hirata
,
K.
,
2015
, “
Improvement of Exhaust Gas Emissions by Exhaust Gas Recirculation System Combined Marine Diesel Engine and Gas Engine
,”
85th Annual Meeting of Japan Institute of Marine Engineering
, Tokyo, Japan, Oct., pp.
17
18
(in Japanese).
16.
ISO
,
2006
, “
Reciprocating Internal Combustion Engines-Exhaust Emission Measurement-Part 1, Test-Bed Measurement of Gaseous and Particulate Exhaust Emissions
,” International Organization for Standardization, Geneva, Switzerland, Standard No.
ISO 8178-1
.
17.
,
X.-C.
,
Chen
,
W.
, and
Huang
,
Z.
,
2005
, “
A Fundamental Study on the Control of the HCCI Combustion and Emissions by Fuel Design Concept Combined With Controllable EGR-Part 2, Effect of Operating Conditions and EGR on HCCI Combustion
,”
Fuel
,
84
(
9
), pp.
1084
1092
.
18.
Maiboom
,
A.
,
Tauzia
,
X.
, and
Hétet
,
J.-F.
,
2008
, “
Experimental Study of Various Effects of Exhaust Gas Recirculation (EGR) on Combustion and Emissions of an Automotive Direct Injection Diesel Engine
,”
Energy
,
33
(
1
), pp.
22
34
.
19.
Hebbar
,
G. S.
, and
Bhat
,
A. K.
,
2013
, “
Control of NOx from a DI Diesel Engine With Hot EGR and Ethanol Fumigation: An Experimental Investigation
,”
Int. J. Automot. Technol.
,
14
(
3
), pp.
333
341
.
20.
Jin
,
K.
,
Takashi
,
O.
,
Yasuhiro
,
D.
,
Ryouji
,
K.
, and
Takeshi
,
S.
,
2000
, “
Combustion and Exhaust Gas Emission Characteristics of a Diesel Engine Dual-Fueled With Natural Gas
,”
Soc. Automot. Eng. Jpn. Rev.
,
21
(
4
), pp.
489
496
.
You do not currently have access to this content.