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Katalytisk avgasrening av fartygsmotorer

Aukland, Torbjörn (1996) In MSc Theses
Department of Automatic Control
Abstract
Recent years intensive measures of land-based emissions have increased the share contributed from ships and other marine activities. The main problem here is the nitrogen oxides emitted from today's fuel-optimized diesel engines used by the majority of ships. ABB Fläkt Marine is one of the very few companies that provides a solution to emissions on nitrogen oxides. This is made with a technique called Selectice Catalytic Reduction using a substance, urea, which is injected into the exhausts to react with the nitrogen oxides in the reduction catalyst to form water, nitrogen and carbon dioxide. The amount of injected urea into an exhaust pipe is controlled by measuring the momentarily load of the engine. However, the optimal injection rate... (More)
Recent years intensive measures of land-based emissions have increased the share contributed from ships and other marine activities. The main problem here is the nitrogen oxides emitted from today's fuel-optimized diesel engines used by the majority of ships. ABB Fläkt Marine is one of the very few companies that provides a solution to emissions on nitrogen oxides. This is made with a technique called Selectice Catalytic Reduction using a substance, urea, which is injected into the exhausts to react with the nitrogen oxides in the reduction catalyst to form water, nitrogen and carbon dioxide. The amount of injected urea into an exhaust pipe is controlled by measuring the momentarily load of the engine. However, the optimal injection rate tends to drift slowly under longer periods of time causing the actual injection rate to be either too low or too high. The adjustments of these trends have so far been made manually by the company's service engineers, but with just a few more plats of this kind installed on ships around the world this world would soon become too time consuming. The purpose of this master thesis project has therefore been to suggest how these trend adjustments could be carried out automatically. The measurements, mainly made on a ferry between Sweden and Denmark, show a very different dynamical behavior of the catalyst depending on whether the actual injection rate is too low or too high. They also show that variations in the engine's load have to be taken into consideration in some way during the adjustments. The suggested method uses time series analysis and prediction while searching for the optimal injection rate. (Less)
Please use this url to cite or link to this publication:
author
Aukland, Torbjörn
supervisor
organization
year
type
H3 - Professional qualifications (4 Years - )
subject
publication/series
MSc Theses
report number
TFRT-5565
ISSN
0280-5316
language
Swedish
id
8848734
date added to LUP
2016-03-24 17:59:58
date last changed
2016-03-24 17:59:58
@misc{8848734,
  abstract     = {Recent years intensive measures of land-based emissions have increased the share contributed from ships and other marine activities. The main problem here is the nitrogen oxides emitted from today's fuel-optimized diesel engines used by the majority of ships. ABB Fläkt Marine is one of the very few companies that provides a solution to emissions on nitrogen oxides. This is made with a technique called Selectice Catalytic Reduction using a substance, urea, which is injected into the exhausts to react with the nitrogen oxides in the reduction catalyst to form water, nitrogen and carbon dioxide. The amount of injected urea into an exhaust pipe is controlled by measuring the momentarily load of the engine. However, the optimal injection rate tends to drift slowly under longer periods of time causing the actual injection rate to be either too low or too high. The adjustments of these trends have so far been made manually by the company's service engineers, but with just a few more plats of this kind installed on ships around the world this world would soon become too time consuming. The purpose of this master thesis project has therefore been to suggest how these trend adjustments could be carried out automatically. The measurements, mainly made on a ferry between Sweden and Denmark, show a very different dynamical behavior of the catalyst depending on whether the actual injection rate is too low or too high. They also show that variations in the engine's load have to be taken into consideration in some way during the adjustments. The suggested method uses time series analysis and prediction while searching for the optimal injection rate.},
  author       = {Aukland, Torbjörn},
  issn         = {0280-5316},
  language     = {swe},
  note         = {Student Paper},
  series       = {MSc Theses},
  title        = {Katalytisk avgasrening av fartygsmotorer},
  year         = {1996},
}