Marine Exhaust Emissions Legislation - Wartsila 31 Product Manual

12. Exhaust Emissions
Smoke can be black, blue, white, yellow or brown in appearance. Black smoke is mainly
comprised of carbon particulates (soot). Blue smoke indicates the presence of the products
of the incomplete combustion of the fuel or lubricating oil. White smoke is usually condensed
water vapour. Yellow smoke is caused by NO
significantly prior to discharge to the atmosphere, the condensed NO
a brown appearance.
12.2

Marine exhaust emissions legislation

12.2.1 International Maritime Organization (IMO)
The increasing concern over the air pollution has resulted in the introduction of exhaust
emission controls to the marine industry. To avoid the growth of uncoordinated regulations,
the IMO (International Maritime Organization) has developed the Annex VI of MARPOL 73/78,
which represents the first set of regulations on the marine exhaust emissions.
12.2.1.1 MARPOL Annex VI - Air Pollution
The MARPOL 73/78 Annex VI entered into force 19 May 2005. The Annex VI sets limits on
Nitrogen Oxides, Sulphur Oxides and Volatile Organic Compounds emissions from ship
exhausts and prohibits deliberate emissions of ozone depleting substances.
Nitrogen Oxides, NO
The MARPOL 73/78 Annex VI regulation 13, Nitrogen Oxides, applies to diesel engines over
130 kW installed on ships built (defined as date of keel laying or similar stage of construction)
on or after January 1, 2000 and different levels (Tiers) of NOx control apply based on the ship
construction date. The NO
has developed a detailed NO
EIAPP Certification
An EIAPP (Engine International Air Pollution Prevention) Certificate is issued for each engine
showing that the engine complies with the NO
When testing the engine for NO
and the test is performed according to ISO 8178 test cycles. Subsequently, the NO
to be calculated using different weighting factors for different loads that have been corrected
to ISO 8178 conditions. The used ISO 8178 test cycles are presented in the following table.
Table 12-1
D2: Constant-speed
auxiliary engine applica-
tion
E2: Constant-speed
main propulsion applica-
tion including diesel-
electric drive and all
controllable-pitch pro-
peller installations
12-2
Emissions
x
emissions limit is expressed as dependent on engine speed. IMO
x
Technical Code which regulates the enforcement of these rules.
x
emissions, the reference fuel is Marine Diesel Oil (distillate)
x
ISO 8178 test cycles
Speed (%) 100
Power (%) 100
Weighting 0.05
factor
Speed (%) 100
Power (%) 100
Weighting 0.2
factor
Wärtsilä 31 Product Guide
emissions. When the exhaust gas is cooled
x
regulations set by the IMO.
x
100 100 100
75 50 25
0.25 0.3 0.3
100 100 100
75 50 25
0.5 0.15 0.15
Wärtsilä 31 Product Guide - a1 - 18 October 2016
component can have
2
value has
x
100
10
0.1