[Emission Control Of Exhaust Gases From Marine Engines]
By
Abstract
The main aim of the paper is to identify various technololgy use to conrtol fuel emission in marine ships. Maritime transport has clear environmental advantages: it expends relatively little energy and its infrastructure requirements are small compared to land-based transport modes. Due to low energy need, shipping is a highly carbon-efficient transport mode, i.e. carbon dioxide emissions are low compared to the weight of cargo transported. Shipping can be up to four times more efficient than road transport. Because of relatively small contribution to greenhouse gas emissions shipping is also good in the terms of mitigation of climate change. However, air pollution from ships has been unregulated until recently. As a result, fuel oils with high sulphur content are widely used and emission control technologies are not required. Ships currently produce about half as much sulphur dioxide (SO2 ) as land-based sources and about a third as much nitrogen oxides (NOx ). The International Institute for Applied Systems Analysis (IIASA) estimates that in Europe the amounts of SO2 and NOx emissions from shipping will surpass land-based sources in the 25 EU member states in 2020. Ships emit several hazardous air pollutants such as sulphur dioxide, nitrogen oxides and fine particles. Once emitted, airborne emissions can travel considerable distances so the shipping emissions affect land air quality. Also the emissions from ships during port stays can be substantial contributor to the local air quality.
Table of Contents
ABSTRACT2
CHAPTER 1: INTRODUCTION5
Background study5
Problem Statement5
Research aims and Objectives6
Significance of the study6
Rationale of the study7
CHAPTER 2: LITERATURE REVIEW9
Formation of emissions in marine diesel engines9
Sulphur dioxide emissions10
Nitrogen oxides emissions12
Particulate matter emissions and smoke13
Available scrubbing technologies14
Environmental impacts and other technical considerations18
Scrubbing technologies devices19
Emission Requirements21
Packed bed scrubber22
Flue Gas Treatment27
Air Scrubber29
CHAPTER 3: METHODOLOGY32
Introduction32
Research Design32
Research Approach33
Literature Search33
Nature Of Data33
Generalisability34
CHAPTER 4: DISCUSSION35
Techniques for reducing emissions from ships35
Miller cycle35
In-engine and operational modifications37
After-treatment on-board controls39
Shore-side controls42
Fuel switching44
FGD Technology44
Wet FGD Technologies46
Dry FGD Technologies51
Other Control Technologies58
Approaches for Reducing Diesel Emissions61
Engine Controls62
Exhaust Controls64
Flow-Through Diesel Oxidation Catalysts66
Diesel Oxidation Catalyst67
Filter Regeneration Catalysts68
Impact of Sulfur on Oxidation Catalysts69
CHAPTER 5: CONCLUSION71
Future Directions74
REFERENCES77
CHAPTER 1: INTRODUCTION
Background study
Emissions of acidifying sulphur oxides (SOX) from marine diesel engines have been subject to scrutiny for many years and, as a consequence, new regulations have emerged. From the beginning of 2010, all ships at berth for longer than two hours in ports within the European Union have been required to reduce their sulphur dioxide emissions by switching to marine fuel oil with a sulphur content of 0.1% or less(Flagan, 2012, pp. 236-284). To fulfi l the requirements of upcoming emission regulations, shipowners have two alternatives - switching to costly low-sulphur fuel or treating engine exhaust gases in a sulphur-removing scrubber.
In 2008, the International Maritime Organization (IMO) decided on a progressive global reduction of sulphur oxides emissions from ships. From the current upper limit of 4.5% for the sulphur content of any fuel oil used globally on vessels, the cap on sulphur content is to be gradually reduced to 0.50% by 2020. In special SOX Emission Control Areas (SECAs) such as ...