1,721,009 research outputs found
Air Pollution from Ships - Emission Measurements and Impact Assessments
No full textEnvironmental 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 <0.30µm were not covered by the study. The size distribution of particles is potentially important in impact assessments since there are indications that fine and ultrafine particles are associated with higher health risks than coarse particles. The particle mass was reduced by half from a shift from a heavy fuel oil with 1.6% sulphur content to a marine gasoil with 0.03% sulphur.
The results from the impact assessments point in favour of the abatement technologies selective catalytic reduction (SCR), shore side electricity (SSE) connection and the use of fuel with low sulphur content in a local and regional cost benefit perspective. The SSE seemed beneficial also from a shipowner perspective. SCR was also analysed in a life cycle perspective and it was concluded there were overall benefits from its use for all impact categories except global warming
Air Pollution from Ships - Emission Measurements and Impact Assessments
No full textEnvironmental 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. Size
Particle Emissions from Ships: Dependence on Fuel Type
No full textThis paper presents the results of field emission measurements that have been carried out on the 4500-kW four-stroke main engine on-board a product tanker. Two fuel qualities-heavy fuel oil (HFO) and marine gas oil (MGO)-have been tested on the same engine for comparable load settings. A fuel switch within the marine sector is approaching and the aim of this study is to draw initial conclusions on the subsequent effects on ship exhaust gas composition and emission factors with a focus on particles. Measurements on exhaust gas concentrations of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), total hydrocarbons (HCs), and particulate matter (PM) were conducted. The gases, except SO2, did not show any major differences between the fuels. Specific PM emissions were generally higher for HFO than for MGO; however, for the smallest size-fraction measured containing particles 0.300.40 mu m in diameter, the opposite is observed. This finding emphasizes that to minimize negative health effects of particles from ships, further regulation may be needed to reduce small-sized particles; a fuel shift to low sulfur fuel alone does not seem to accomplish this reduction. The average of this and previously published data from on-board studies on particle emissions from ships results in emissions factors of 0.33 and 1.34 g/kWh for marine distillate oil (MDO) and HFO, respectively. Accounting for 1 standard deviation in each direction from the average values gives a range of 0.18-0.48 g/kWh for MDO and 0.56-2.12 g/kWh for HFO
Greenhouse gas emissions from ships in ports – case studies in four continents
No full textEmissions of GHG from the transport sector and how to reduce them are major challenges for policy makers. The purpose of this paper is to analyse the level of greenhouse gas (GHG) emissions from ships while in port based on annual data from Port of Gothenburg, Port of Long Beach, Port of Osaka and Sydney Ports. Port call statistics including IMO number, ship name, berth number and time spent at berth for each ship call, were provided by each participating port. The IMO numbers were used to match each port call to ship specifications from the IHS database Sea-web. All data were analysed with a model developed by the IVL Swedish Environmental Research Institute for the purpose of quantifying GHG emissions (as CO2-equivalent) from ships in the port area. Emissions from five operational modes are summed in order to account for ship operations in the different traffic areas. The model estimates total GHG emissions of 150,000, 240,000, 97,000, and 95,000 tonnes CO2 equivalents per year for Gothenburg, Long Beach, Osaka, and Sydney, respectively. Four important emission-reduction measures are discussed: reduced speed in fairway channels, on-shore power supply, reduced turnaround time at berth and alternative fuels. It is argued that the potential to reduce emissions in a port area depends on how often a ship revisits a port: there it in general is easier to implement measures for high-frequent liners. Ships that call 10 times or less contribute significantly to emissions in all ports.</p
Emission factors for methane engines on vehicles and ships [Elektronisk resurs] : with a focus on methane emissions
No full textThis report covers emissions from methane engines on road vehicles and ships, and aims at presenting relevant emission factors for different engines and vehicle types and ships. A focus is placed on methane emissions, and both engine emissions and non-engine emissions are included. Methane fuel passes through the engine to varying degrees in different engine types causing a main part of the methane emissions from methane fueled road vehicles and ships.As introduction to the emission calculations we describe the use of different types of methane fuel, the use of different engine types, and typical properties of vehicles/vessels with different types of methane engines. The report presents emission factors for heavy duty vehicles in the categories “Heavy Goods Vehicle” (HGV) and “Bus”, emission factors for light duty vehicles are presented for the categories “Passenger car” and “Light Commercial Vehicle” (LCV), while emission factors for ships do not contain any subcategories.There is generally a shortage of measurement data that cause high uncertainties for many emissions factors.Emission factors for 2019 are summarized in the report. Different regulations apply which a.o. cause the large difference seen for some emissions between land-based vehicles and ships.Den här rapporten beskriver emissioner från metanmotorer på vägfordon och fartyg. Syftet är att ta fram relevanta emissionsfaktorer för olika motortyper och fordonstyper, alternativt fartyg. Fokuset är att presentera emissionsfaktorer för metanutsläpp och uppskattningarna omfattar både emissioner från motorer och från bränslesystemen ombord. Metan passerar genom motorerna i olika grad beroende på förbränningsteknik vilket utgör den främsta källan till metanutsläpp från metandrivna land- och sjötransporter.Som en bakgrund till emissionsberäkningarna beskriver vi de olika typerna av metanbränsle, de olika motortyperna, och hur kombinationer av dessa används på fordonstyper respektive fartyg. De transportslag som ingår är ”Heavy duty vehicles” där emissionsfaktorer presenteras för kategorierna ”Heavy Goods Vehicles” (HGV, tunga lastbilar) och ”Bus” (bussar), “Light duty vehicles” med emissionsfaktorer för kategorierna ”Passenger car” och "Light Commercial Vehicle” (passagerarbilar och lätta kommersiella fordon), och “Ships” (fartyg).Endast få emissionsmätningar finns tillgängliga vilket gör att många av de emissionsfaktorer som vi presenterar bedöms ha stor osäkerhet.Emissionsfaktorer för 2019 summeras i rapporten. En viktig anledning till skillnaderna i emissionsfaktorer mellan olika landbaserade fordonsslag och fartyg är att utsläppsregleringarna skiljer sig mycket åt.</p
Energy efficient port calls - A study of Swedish shipping with international outlooks
No full textThe calculation of the total fuel consumption of Swedish shipping in 2014 resulted in approximately 1 500 000 tonnes of fuel. Significantly more fuel is used at sea than in the port areas. In Sweden, the high-frequency shipping services contribute to a significant amount of the total fuel consumption: the ships that call more than 100 times/year stand for about 19 percent of the total consumption while ships with less than 10 calls contributed to 38 percent. Fuel consumption and CO2-equivalent emissions for ships in three Swedish ports and three foreign ports are presented and discussed, see table below. Comparisons between the ports can be made only in a context of ship traffic characteristics, e.g. ship types, ship sizes and call frequency. Further, the geographical boundaries of the inventory affect the result. The average CO2- equivalents per port call reveal great differences between the ports. Port of Long Beach and Port of Sydney have a high ratio of large ships, which partly explain the high average values. Large ships have larger installed main engines and auxiliary engines, and stay a longer time at berth for the loading and unloading of cargo. More than half of the emissions from ships in ports originate from the time at berth. International shipping contributes to approximately 2.4 percent of greenhouse gas (GHG) emissions, and its share is expected to increase in the future. This stands in contrast to ambitions to reduce the use of fossil fuels. In order to reach sustainability objectives international steps towards more strict policies and regulations are necessary for the shipping sector. National efforts are in many ways limited to voluntary incentive schemes, and local port initiatives cannot significantly influence overall energy needs and emission levels. However, it is argued that an individual port can still facilitate a transfer to more energy efficient shipping and a reduction of emissions from ships in the port areas. For example, ports can implement environmentally differentiated port dues and give rebates to ship owners that perform well, manage and administer the supply of alternative fuels and on-shore power connections, and work for a reduction of ship speed in the fairway channel. The call frequency of individual ships to the same port is of high relevance to the improvement potential. The diverse conditions between ports suggest that emission abatement measures need to be customer-tailored for specific ports.The purposes of this study are to calculate the fuel consumption and carbon dioxide emissions for Swedish shipping and for ships in a selection of national and foreign ports. Further, abatement potentials from different measures are analysed and discussed for the different ports and shipping types
Emissions of NOX and particles from manoeuvring ships
No full textShip 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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