Potential Measures to Reduce Emission from Ships

POTENTIAL MEASURE TO
REDUCE EMISSION FROM
SHIPS

TABLE OF CONTENTS
INTRODUCTION...........................................................................................................................1
AIM AND OBJECTIVES................................................................................................................2
SCOPE AND LIMITATION...........................................................................................................2
Organisation of the dissertation.......................................................................................................2
SOURCE INFORMATION ............................................................................................................3
REFERENCES................................................................................................................................4

INTRODUCTION
Climatic changes has occurred due to many reasons among which one of the causes is
due to various emissions that are caused from ships and are needed to be controlled.
International shipping, on an average contributes to approx 2.4% of the anthropogenic
greenhouse gases (GHG) emissions. For reducing the emissions from the ships in the port areas,
various operational as well as potential measures have been used and are usually considered to
entail bigger reductions than the other characteristics. There are various types of emissions which
need to be controlled such as GHG, NOx, SOx etc. Various technologies are also there which
can help in controlling these emissions. Although it is not possible to achieve 100% efficiency
because of some factors such as friction, dissipation of heat etc., but it can be managed to an
extent. Inside the engine of a ship, there is a huge mechanical structure involving some movable
parts as well, but in that case the efficiency of work that can be achieved is about 75 – 85% so
that it is in suitable running conditions. In the engine, there is combustion of gases which emits
various harmful gases for the surroundings. Therefore, it also affects the environment and causes
pollution in the marine environment. Various technologies can help in reducing the amount of
harmful emissions in the exhaust system of the ship. These are discussed as following :
Reduction of NOx emission
The amount of NOx that is present in the marine engine's exhaust emission is because of
the high combustion temperature which reacts with the nitrogen available in the atmosphere and
is being supplied for combustion. One of the method for reduction of this emissions is discussed
as following :
Humid Air Method
Before the water vapours are supplied to the cylinder, it is being mixed with the
combustion air. From the T/C blower, the air is being passed by the help of a cell that moistens
and cools down the hot air having the moisture from the chilled water until the air saturation is
being achieved. Most of the times, the saline water is used in this process. It is first done by
heating it with the jacket water and the turbo charger heat, then it is being left over the brine and
disposed off the sea. This way can help in reducing the emission by 70-80%.
Reduction of SOx emission
Sulphur oxides or SOx are formed during the combustion process inside the engine due to
the sulphur content present in the fuel. One of the method that can be used to reduce for its
reduction is the use of low sulphur fuel oil as this method is quite expensive from the other
methods, but the most commonly used.
AIM AND OBJECTIVES
To Analyse the technological improvement and international mechanism for regulating ai
r emissions from ships in west Africa
Objectives
1