| 1. |
- Andersson, Karin, 1952, et al.
(författare)
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Environmental trade-offs in nitrogen oxide removal from ship engine emissions
- 2011
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Ingår i: Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment. - 2041-3084 .- 1475-0902. ; 225:1, s. 33-42
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Konferensbidrag (refereegranskat)abstract
- The emissions of nitrogen oxides (NOx) from ship engines constitute an increasing part of the total global emissions of NOx while the share from land-based sources is decreasing. In the coming years, new regulations will set limits to emissions in specific areas and various technical countermeasures will be developed and implemented. However, when taking technical measures against emissions on a local scale, there is always a risk of inducing an increase in the total environmental impact related to the technology used, owing to increased energy use and emissions in other places.In the present study, an investigation of the difference in environmental impact from passenger transport vessels with and without catalytic NOx emission purification was performed in a life cycle assessment. The production and transport of chemicals used in the catalyst are included in the study.The study shows that the use of selective catalytic reduction (SCR) gives a considerable decrease in the environmental impact compared with using a diesel engine without a catalyst. The transport of urea solution over a 500 km distance makes a very small contribution to the total environmental impact. The global warming potential is the only impact category for which values are increased when including the urea production and transport. When looking at the contribution from urea to the total impact from the SCR process, the increase is less than 10 per cent for most impact categories.
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| 2. |
- Moldanová, Jana, et al.
(författare)
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Physical and chemical characterisation of PM emissions from two ships operating in European Emission Control Areas
- 2013
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Ingår i: Atmospheric Measurement Techniques. - : Copernicus GmbH. - 1867-8548 .- 1867-1381. ; 6:12, s. 3577-3596
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Tidskriftsartikel (refereegranskat)abstract
- In this paper emission factors (EFs) for particulate matter (PM) and some sub-components as well as gaseous substances were investigated in two onboard measurement campaigns. Emissions from two 4-stroke main engines were measured under stable-load conditions. The impact of varying engine load on the emissions was investigated on one of the engines, and the impact of fuel quality on the other, where heavy fuel oil (HFO) with sulphur content 1% and 0.5% and marine gas oil (MGO) with sulphur content 0.1% were used. Furthermore, emissions from one auxiliary engine were studied. The measured EFs for PM mass were in the range of 0.3 to 2.7 g kg−1 fuel with the lowest values for emissions from the combustion of MGO, and the highest values for HFO with a sulphur content of 1%. The PM mass size distribution was dominated by particles in accumulation mode. Emission factors for particle numbers EF(PN) in the range of 5 × 1015–1 × 1017 # kg−1 fuel were found, the number concentration was dominated by particles in the ultrafine mode and ca. 2/3 of the particle number were non-volatile. The most abundant component of the PM mass was organic carbon, making up 25–60% of the PM. The measured EFs for organic carbon (OC) were 0.6 g kg−1 fuel for HFO and 0.2 g kg−1 fuel for MGO. Elemental carbon (EC) made up 10–38% of the PM mass, with no significant differences between HFO and MGO fuels. The concentrations of metals on sampled filters were investigated with energy dispersive X-ray fluorescence (EDXRF) and the detected metal elements in exhaust when using HFO was concluded to originate from both the fuel (V, Ni, Fe) and the lubricant (Ca, Zn), while for the case of MGO combustion, most of the metals were concluded to originate from the lubricants. The measured emission factors for sulphate particles, EF (SO2−4), were low, ca. 0.1–0.2 g kg−1 fuel for HFO with 1% sulphur, 0.07–0.09 g kg−1 fuel for HFO with 0.5% sulphur and 0.003–0.006 g kg−1 fuel for MGO. This corresponds to 0.1–0.8% and 0.1–0.6% of fuel S converted to PM sulphate for HFO and MGO, respectively. Scanning transmission electron microscopy (STEM) images of the collected PM showed three different types of particles: relatively pure soot; char and char-mineral particles; and amorphous, probably organic particles containing inorganic impurities. The maps of elements obtained from STEM showed a heterogeneous composition of primary soot particles with respect to the trace metals and sulphur. Temperature-programmed oxidation (TPO) of PM showed higher soot oxidation reactivity compared to automotive diesel soot, PM from the HFO exhaust being more reactive than PM from the MGO exhaust. Oxidative potential measured as the rate of consumption of Dithiothreitol (DTT) was for the first time measured on PM from ship exhaust. The obtained values were between 0.01 and 0.04 nmol DTT min−1 μg−1 PM, which is quite similar to oxidative potentials of PM collected at urban and traffic sites. The data obtained during the experiments add information about emission factors for both gaseous and PM-bound compounds from ship engines using different fuels and under different engine-load conditions. Observed variability of the EFs illustrates uncertainties of these emission factors as a result of influences from fuel and lubricant composition, from differences between individual engines and from the differences in sampling conditions.
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| 3. |
- Styhre, Linda, et al.
(författare)
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Energieffektiv svensk sjöfart
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sjöfarten står inför en enorm utmaning med krav på 40-50 procent minskning av koldioxidutsläpp till 2050 jämfört med 2005 års utsläpp, samtidigt som det finns en politisk vilja att öka andelen sjötransporter. Kraftigt ökad energieffektivisering kommer att vara avgörande för att möta utsläppskraven. Dock visar projektioner att det globalt kommer att vara svårt att minska sjöfartens utsläpp via åtgärder som är kända idag. Den här studien pekar på vikten av en snabbare implmentering av kända åtgärder och fortsatt utveckling av nya energireducerande tekniker, verktyg och metoder. Ökad energieffektivitet inom sjöfarten kan ske genom oeprativa. logistiska, tekniska, avtals- och markndsrelaterade och kommunikativa åtgärder. Åtgärder kopplade till varandra och bör med fördel betraktas ut ett systemperspektiv.
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| 4. |
- Styhre, Linda, 1975, et al.
(författare)
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Energy efficient shipping – between research and implementation
- 2013
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Ingår i: Proceedings of IAME2013 Conference, Marseille, France, 3-5 July 2013.
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Konferensbidrag (refereegranskat)abstract
- Shipping contributes to a substantial amount of CO2 emissions globally. To meet sustainability objectives, EU has requested a minimum 40% reduction of CO2 emissions from shipping by 2050 compared to 2005 levels. Increased energy efficiency - defined as energy used per transportation work - through better operational practices, new technologies and improved logistic systems will be key issues in the effort to abate these emissions.The objective of this paper is to identify and describe the gap between present knowledge and implementation of available energy efficient measures among shipping companies. The results show that measures that cost-efficiently decrease the energy consumption of shipping companies are available; however, many of them are not implemented or used in daily operations.Implementation of operational and structural measures faces many challenges. This study highlights that there is very little time to plan, control and follow-up on voyages in shipping companies, and the crews seldom receive feedback on bunker consumption during or after a voyage. There is also to some extent a lack of incentives to apply new technologies and methods among crew and on-shore staff in the shipping companies.
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| 5. |
- Winnes, Hulda, 1975
(författare)
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Air Pollution from Ships - Emission Measurements and Impact Assessments
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Environmental impact and air pollution from ships have received increasing attention the last decades. Due to combustion characteristics of typical marine engines and a wide spread use of unrefined fuel, the global fleet emits significant amounts of SO2, NOX and particles to air. Impact assessments and information on emitted amounts are important inputs to decision-making in regulation development and also for ship designers who aim at environmentally improved designs.In order to assess the impacts caused by ship emissions to air, information on ships’ activities in an area or the corresponding fuel use is essential. In combination with an emission factor that state the mass of an emitted pollutant related to either the work produced by ship engines or the mass of combusted fuel, the total emitted mass of a pollutant is established.Ship engines are diverse and the emission factors are insufficiently quantified for certain operational modes and specific pollutants which makes assessments difficult. Measurements on-board ships were thus conducted in order to determine emission characteristics during manoeuvring periods and for engines operating on fuels of different qualities. The measurement studies comprised three engines and focussed on emissions of particles and NOX.Elevated levels of numbers of small particles (0.30-0.40µm) were observed during manoeuvring periods and from combustion of marine distillate oils. Sizes
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| 6. |
- Winnes, Hulda, 1975, et al.
(författare)
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Emissions of NOX and particles from manoeuvring ships
- 2010
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Ingår i: Transportation Research Part D: Transport and Environment. - : Elsevier BV. - 1361-9209. ; 15:4, s. 204-211
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Tidskriftsartikel (refereegranskat)abstract
- Ship exhausts contain high levels of particles and nitrogen oxides due to the heavy fuel oil normally used for combustion and the combustion characteristics of most ship engines. The quantification of exhaust gases during ships' manoeuvring has not received a lot of attention. This work presents results from emission measurements for the main engines onboard two ships and characterises quantities and potential impacts of emissions from manoeuvring. The observed nitrogen oxides levels vary throughout the manoeuvring period but at lower levels than at cruising speed. With a selective catalytic reduction system in operation, however, the situation is reversed. Elevated levels of particle emissions, measured as number concentrations, are detected throughout the manoeuvring. There are also peak concentrations of particles, at both the start-up and the shut-down of the engines. The increase is big enough to suspect a notable impact on air quality in port cities over the short period that manoeuvring at reduced speeds takes place. (C) 2010 Elsevier Ltd. All rights reserved.
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