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Keyword: emission reduction

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Adaptive Observer for Nonlinearly Parameterized Hammerstein System With Sensor Delay—Applied to Ship Emissions Reduction

Nielsen, Kræn Vodder; Blanke, Mogens; Eriksson, Lars

Taking offspring in a problem of ship emission reduction by exhaust gas recirculation control for large diesel engines, an underlying generic estimation challenge is formulated as a problem of joint state and parameter estimation for a class of multiple-input single-output Hammerstein systems with first-order dynamics, sensor delay, and a bounded time-varying parameter in the nonlinear part. This brief suggests a novel scheme for this estimation problem that guarantees exponential convergence to an interval that depends on the sensitivity of the system. The system is allowed to be nonlinear, parameterized, and time dependent, which are characteristics of the industrial problem we study. The approach requires the input nonlinearity to be a sector nonlinearity in the time-varying parameter. Salient features of the approach include simplicity of design and implementation. The efficacy of the adaptive observer is shown on simulated cases, on tests with a large diesel engine on test bed, and on tests with a container vessel.

IEEE Transactions on Control Systems Technology ( Volume: 26, Issue: 4, July 2018) / 2017
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Modelling of temporal and spatial evolution of sulphur oxides and sulphuric acid under large, two-stroke marine engine-like conditions using integrated CFD-chemical kinetics

Pang, Kar Mun; Karvounis, Nikolas; Walther, Jens Honore; Schramm, Jesper; Glarborg, Peter; Mayer, Stefan

In this work, three-dimensional computational fluid dynamics (CFD) studies of sulphur oxides (SOx) and sulphuric acid (H2SO4) formation processes in a large, low speed two-stroke marine diesel engine are carried out. The current numerical study aims to investigate the conversion of sulphuric dioxide (SO2) to sulphuric trioxide (SO3) and the possibility of H2SO4 condensation which are the prerequisites to better understand the corrosion-induced wear phenomenon. This is achieved with the aid of the implementation of a multicomponent surrogate model, which comprises a skeletal n-heptane mechanism and a reduced sulphur subset mechanism. In the present work, performance of the coupled CFD-chemical kinetic model is evaluated using both qualitative and quantitative methods. The modelling results show that the temporal and spatial evolutions of SOx predicted by the skeletal model are similar to those by the base mechanism. Predictions of the variations of SOx and the associated SO2 to SO3 conversion in response to the change of fuel sulphur content, swirl velocity, start of injection, scavenge pressure and humidity qualitatively agree with numerical and experimental results from the literature. The model is further evaluated using the measured SO2 to SO3 conversion levels in a low load, low scavenge pressure case and a low load, high scavenge pressure case. The absolute values of simulated and measured conversion levels are close, although the former appear to be higher. The current results show that the flame impinges at the cylinder liner near top dead centre. The gas is cooled rapidly by the wall temperature and H2SO4 is produced in the region where the local temperature is less than 600 K. Based on the flue gas correlation, the acid dew point temperature is higher than the wall temperature, suggesting that acid condensation may begin early at the top part of the cylinder liner. The predicted distribution corresponds well with the distribution of corroded parts observed in service engines. The model is expected to serve as an important tool to simulate the rates of SO2 absorption into lubricating oil film and H2SO4 condensation in this combustion system.

Applied Energy, Volume 193 / 2017
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paper

The implications of the new sulphur limits on the European Ro-Ro sector

Zis, Thalis; Psaraftis, Harilaos N.

In an effort to reduce the environmental impacts of maritime transportation, the International Maritime Organization (IMO) designated special Sulphur Emission Control Areas (SECAs) where ships are required to use low-sulphur fuel. In January 2015, the sulphur limit within SECAs was lowered to 0.1%, which can only be achieved if vessels are using pricier ultra-low sulphur fuel, or invest in abatement technologies. The increased operating costs borne by Ro-Ro operators in SECAs due to the stricter limits can result in the shutting down of some routes and a redistribution of cargo flows with land-based alternatives. The exact repercussions of the new sulphur limits are difficult to identify in the wake of significant recent reductions of the fuel prices for both low-sulphur and heavy fuel oil. This paper presents a modal split model that estimates modal shifts vis-a-vis competing maritime and land-based modes available to shippers. This allows examining the implications of the recent low prices to modal choice, and the influence a potential increase in fuel prices may have. The model is applied to seven routes affected by the regulation based on data from a leading European Ro-Ro operator. Sensitivity analyses on market share data, cargo values, freight rates, and haulers rates are conducted. Emissions inventories are constructed to assess the environmental efficacy of the SECA regulation. The novelty of the proposed model lies in the examination of the ex-post implications of shutting down a service and the redistribution of transport. Recommendations to mitigate and reverse the negative side-effects of such environmental legislation are proposed.

Transportation Research Part D: Transport and Environment, Volume 52, Part A, / 2017
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Green maritime transportation: Market based measures

Psaraftis, Harilaos N.

The purpose of this chapter is to introduce the concept of Market Based Measures (MBMs) to reduce Green House Gas (GHG) emissions from ships, and review several distinct MBM proposals that have been under consideration by the International Maritime Organization (IMO). The chapter discusses the mechanisms used by MBMs, and explores how the concept of the Marginal Abatement Cost (MAC) can be linked to MBMs. It also attempts to discuss the pros and cons of the submitted proposals.

Book chapter in Green Transportation Logistics: The Quest for Win-Win Solutions / 2016
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Payback Period for Emissions Abatement Alternatives: Role of Regulation and Fuel Prices

Zis, Thalis; Angeloudis, Panagiotis; Bell, Michael G. H.; Psaraftis, Harilaos N.

As of January 2015, the new maximum limit of fuel sulfur content for ships sailing within emission control areas has been reduced to 0.1%. A critical decision for ship owners in advance of the new limits was the selection of an abatement method that complies with the regulations. Two main options exist: investing in scrubber systems that remove sulfur dioxide emissions from the exhaust and switching to low-sulfur fuel when sailing in regulated waters. The first option would involve significant capital costs, while the latter would lead to operating cost increases because of the higher price of the fuel used. This paper presents a literature review of emissions abatement options and relevant research in the field. A cost–benefit methodology to assess emission reduction investments from ship owners is also presented. A study examined the effects of recent drops in bunker fuel price to the payback period of a potential scrubber investment. The results show that lower prices would significantly delay the payback period of such investments, up to two times in some cases. The case studies present the emissions generation through each option for representative short sea shipping routes. The repercussions of low-sulfur policies on large emission reduction investments including cold ironing are examined, along with implications of slow steaming for their respective payback periods. Recommendations are made for research in anticipation of future regulations and technological improvements.

Transportation Research Record. 2016;2549(1) / 2016
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paper

Regulation of Greenhouse Gas Emissions from International Shipping and Jurisdiction of States

Tanaka, Yoshifumi

The regulation of greenhouse gas emissions from international shipping is becoming a matter of increasing concern. Two issues arise in particular. The first issue concerns the elaboration of rules on this subject. In this regard, Annex VI of the International Convention for the Prevention of Pollution from Ships (MARPOL), amended in 2011, constitutes a key instrument because it was the first legally binding climate change instrument since the Kyoto Protocol. The second issue relates to effective compliance with relevant rules. While the flag State has the primary responsibility to implement relevant rules concerning the regulation of greenhouse gas emissions from international shipping, the flag State responsibility alone is inadequate to secure effective compliance with relevant rules. Thus, there is a need to examine the question whether and to what extent coastal and port States can regulate greenhouse gas emissions from vessels in international law. This article seeks to address these two issues. The article concludes that while port States can perform a valuable role in effectuating global rules provided in MARPOL Annex VI, port State control encounters several challenges. Thus, securing compliance with relevant rules should be an important issue in the regulation of greenhouse gas emissions from international shipping.

Review of European, Comparative & International Environmental Law, 25( 3) / 2016
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paper

Being Green on Sulphur: Targets, Measures and Side-Effects

Kontovas, Christos A.; Panagakos, George; Psaraftis, Harilaos N.; Stamatopoulou, Eirini

Green House Gas (GHG) emissions are not the only emissions of concern to the international transport community. SOx emissions are non-GHG emissions that are caused by the presence of sulphur in the fuel. As the maximum percentage of sulphur in automotive and aviation fuels is strictly regulated in most countries around the world, much of the attention in recent years has focused on maritime transport. The attention mainly stems from the fact that in marine fuels the percentage of sulphur can be very high: it can be as high as 4.5 % in Heavy Fuel Oil (HFO), which is the fuel typically used in all deep-sea trades. Even though the amounts of SOx produced by ships are substantially lower than CO2, SOx emissions are highly undesirable as they cause acid rain and undesirable health effects in humans and animals. To mitigate these adverse environmental effects, the international shipping community has taken substantial policy measures. With the introduction of new limits for the content of sulphur in marine fuels in Northern European and North American sea areas, short-sea companies operating in these areas will face substantial additional cost. As of 1/1/2015, international regulations stipulate, among other things, a 0.1 % limit in the sulphur content of marine fuels, or equivalent measures limiting the percent of SOx emissions to the same amount. As low-sulphur fuel is substantially more expensive than HFO, there is little or no room within these companies current margins to absorb such additional cost, and thus significant price increases must be expected. Unlike its deep-sea counterpart, in short-sea shipping such a freight rate increase may induce shippers to use land-based alternatives (mainly road). A reverse shift of cargo would go against the EU policy to shift traffic from land to sea to reduce congestion, and might ultimately (under certain circumstances) increase the overall level of CO2 emissions along the entire supply chain. The purpose of this chapter is to investigate the potential effect of sulphur regulations on the share of cargo transported by the waterborne mode vis-à-vis land-based alternative

Green Transportation Logistics. International Series in Operations Research & Management Science, vol 226 / 2016
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book

Being green on sulphur: Targets, measures and side-effects

Kontovas, Christos A.; Panagakos, George; Psaraftis, Harilaos N.; Stamatopoulou, Eirini

Green House Gas (GHG) emissions are not the only emissions of concern to the international transport community. SOx emissions are non-GHG emissions that are caused by the presence of sulphur in the fuel. As the maximum percentage of sulphur in automotive and aviation fuels is strictly regulated in most countries around the world, much of the attention in recent years has focused on maritime transport. The attention mainly stems from the fact that in marine fuels the percentage of sulphur can be very high: it can be as high as 4.5 % in Heavy Fuel Oil (HFO), which is the fuel typically used in all deep-sea trades. Even though the amounts of SOx produced by ships are substantially lower than CO2, SOx emissions are highly undesirable as they cause acid rain and undesirable health effects in humans and animals. To mitigate these adverse environmental effects, the international shipping community has taken substantial policy measures. With the introduction of new limits for the content of sulphur in marine fuels in Northern European and North American sea areas, short-sea companies operating in these areas will face substantial additional cost. As of 1/1/2015, international regulations stipulate, among other things, a 0.1%limit in the sulphur content of marine fuels, or equivalent measures limiting the percent of SOx emissions to the same amount. As low-sulphur fuel is substantially more expensive than HFO, there is little or no room within these companies current margins to absorb such additional cost, and thus significant price increases must be expected. Unlike its deep-sea counterpart, in short-sea shipping such a freight rate increase may induce shippers to use landbased alternatives (mainly road). A reverse shift of cargo would go against the EU policy to shift traffic from land to sea to reduce congestion, and might ultimately (under certain circumstances) increase the overall level of CO2 emissions along the entire supply chain. The purpose of this chapter is to investigate the potential effect of sulphur regulations on the share of cargo transported by the waterborne mode vis-à-vis land-based alternatives.

Book chapter in Psaraftis H. (eds) Green Transportation Logistics. International Series in Operations Research & Management Science / 2016
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paper

Orchestrating Transnational Environmental Governance in Maritime Shipping

Lister, Jane; Taudal Poulsen, René; Ponte, Stefano

Maritime shipping is the transmission belt of the global economy. It is also a major contributor to global environmental change through its under-regulated air, water and land impacts. It is puzzling that shipping is a lagging sector as it has a well-established global regulatory body—the International Maritime Organization. Drawing on original empirical evidence and archival data, we introduce a four-factor framework to investigate two main questions: why is shipping lagging in its environmental governance; and what is the potential for the International Maritime Organization to orchestrate emerging private ‘green shipping’ initiatives to achieve better ecological outcomes? Contributing to transnational governance theory, we find that conditions stalling regulatory progress include low environmental issue visibility, poor interest alignment, a broadening scope of environmental issues, and growing regulatory fragmentation and uncertainty. The paper concludes with pragmatic recommendations for the International Maritime Organization to acknowledge the regulatory difficulties and seize the opportunity to orchestrate environmental progress.

Global Environmental Change, Volume 34 / 2015
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Environmental Balance of Shipping Emissions Reduction Strategies

Zis, Thalis; North, Robin Jacob; Angeloudis, Panagiotis

Maritime shipping is regarded as the most efficient mode of transport; however, its contribution to climate change through greenhouse gas emissions and the health issues related to shipping activity near residential centers cannot be neglected. In recent years, the efforts of regulators, ship operators, and port authorities have led to actions for ship emissions reduction to improve shipping's environmental performance. This work builds on an activity-based methodology that allows the estimation of emissions and examines environmental effects of slow steaming, fuel regulations, near-port speed-reduction schemes, and cold ironing. Pollutant emissions of carbon dioxide, sulfur dioxide, nitrogen oxides, and black carbon are modeled. A linear programming model minimizes fuel consumption through speed differentiation on a shipping line's routes based on fuel costs and binding regulations in each segment of the journey. Although the examined emissions-reduction actions may have a positive regional environmental effect by cutting emissions, it is possible that additional emissions are generated elsewhere because of increased sailing speeds beyond regulated areas. Trade-offs between pollutants are observed for reduction actions that may have a positive effect on some emission species but at the same time result in additional particulate matter and black carbon emissions. The presented framework allows key actors to conduct comprehensive studies and design improved emissions reduction actions with fewer negative impacts in other areas.

Transportation Research Record, 2015;2479(1) / 2015
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