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Prospective life cycle assessment of solid recovered fuel utilization and marine fuel production in cement plants

Daniel Fozer, Mikołaj Owsianiak & Michael Zwicky Hauschild

Incumbent clinker production practices fall short of meeting carbon-emission neutral targets, pressing the need to implement waste valorization approaches in cement plants to mitigate environmental impacts. However, there is a lack of knowledge on the future environmental performance of emerging waste-to-heat and fuel upcycling in clinker manufacturing. This study examines the prospective life cycle impacts of (1) solid recovered fuel (SRF) utilization and (2) on-site marine fuel production using integrated fluidized bed pyrolysis to substitute fossil fuels in clinker production and marine transportation. Environmental impacts are projected between 2025 and 2050 by applying learning effects in the foreground life cycle inventory and shared socioeconomic pathways (SSP1, SSP2), extended with the 1.9 W m−2 representative concentration pathway (SSP2-RCP1.9), in the background system. The highest decarbonization progress (−538.9 kg CO2-eq (t clinker)−1) is achieved under the SSP2-RCP1.9 development trajectory, driven by avoidance of emissions from waste management systems and converting biogenic carbon-rich municipal solid waste resources. The predicted CO2-eq impacts are found to be lower than the point source emission from raw meal calcination in several SSP scenarios, indicating that carbon-emission neutrality is attainable in combination with retrofitted carbon capture, utilization, and storage (CCUS) technologies. The assessment highlights the potential for burden shifting to other environmental impacts, e.g., particulate matter formation (+37.0 % by 2050), pointing to the need to evaluate additional pyrolysis oil upgrading and NOX emission mitigation strategies. Overall, synergizing waste pyrolysis with clinker production is found to be favourable due to (i) improved energy requirements, (ii) reduced fossil fuel use and impacts on climate change and ecosystem quality, and (iii) high potential for technological learning-driven environmental progress.

Sustainable Production and Consumption / 2025
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Prospects of cold ironing as an emissions reduction option

Zis, Thalis

Cold ironing is the process of providing shorepower to cover the energy demands of ships calling at ports. This technological solution can eliminate the emissions of auxiliary engines at berth, resulting in a global reduction of emissions if the grid powering the ships is an environmentally friendly energy source. This paper conducts a literature review of recent academic work in the field and presents the status of this technology worldwide and the current barriers for its further implementation. The use of cold ironing is mandatory in Californian ports for ship operators and as a result terminal and ship operators were required to invest in this technology. In Europe, all ports will be required to have cold ironing provision by the end of 2025. Other regulations that target local emissions such as Emission Control Areas can have a significant impact on whether cold ironing is used in the future as a potential compliance solution. This paper constructs a quantitative framework for the examination of the technology considering all stakeholders. The role of regulation is shown to be critical for the further adoption of this technology. Illustrative case studies are presented that consider the perspective of ship operators of various ship types, and terminal operators that opt to invest in shorepower facilities. The results of the case studies show that for medium and high fuel price scenarios there is economic motivation for ship operators to use cold ironing. For the port, the cost per abated ton of pollutants is much lower than current estimates of the external costs of pollutants. Therefore, shorepower may be a viable emissions reduction option for the maritime sector, provided that regulatory bodies assist the further adoption of the technology from ship operators and ports. The methodology can be useful to port and ship operators in examining the benefits of using cold ironing as an emissions reduction action.

Transportation Research Part A: Policy and Practice, Volume 119 / 2019
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paper

Protection Systems for DC Shipboard Microgrids

Navid Bayati & Mehdi Savaghebi

In recent years, shipboard microgrids (MGs) have become more flexible, efficient, and reliable. The next generations of future shipboards are required to be equipped with more focuses on energy storage systems to provide all-electric shipboards. Therefore, the shipboards must be very reliable to ensure the operation of all parts of the system. A reliable shipboard MG should be pro-tected from system faults through protection selectivity to minimize the impact of faults and facili-tate detection and location of faulty zones with the highest accuracy and speed. It is necessary to have an across-the-board overview of the protection systems in DC shipboards. This paper provides a comprehensive review of the issues and challenges faced in the protection of shipboard MGs. Furthermore, given the different types of components utilized in shipboard MGs, the fault behavior analysis of these components is provided to highlight the requirements for their protection. The protection system of DC shipboards is divided into three sub-systems, namely, fault detection, lo-cation, and isolation. Therefore, a comprehensive comparison of different existing fault detection, location, and isolation schemes, from traditional to modern techniques, on shipboard MGs is presented to highlight the advantages and disadvantages of each scheme.

Energies / 2021
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Pulling mechanisms and pushing strategies: How to improve Ecosystem Advice Fisheries Management advice within the European Union’s Common Fisheries Policy

Paulina Ramirez-Monsalve, Kåre Nolde Nielsen, Marta Ballesteros, Trine Skovgaard Kirkfeldt, Mark Dickey-Collas, Alyne Elizabeth Delaney, Troels Jacob Hegland, Jesper Raakjær & Poul Degnbol

While European policies have progressed towards an Ecosystem Approach to Fisheries Management (EAFM), limited attention has been paid to the implications for its advisory system. This paper analyzes the advisory landscape in the European Union (EU) by addressing two questions: to what extent can the needed advice be provided? how prepared is the management system to integrate ecosystem advice? We provide a systematic analysis of the relevant advisory bodies, explore gaps related to the requested and delivered advice, and identify paths for improvement. The findings confirm earlier observations of lack of a formalized process to provide and integrate advice in support of an ecosystem approach into EU fisheries management. Instead of enabling existing capacities to embed ecosystem components (eg investments and initiatives made by stakeholders (and authorities) to move to EAFM -pushing strategies), the system relies heavily on mandatory requests from policy makers (pulling mechanisms). Furthermore, social and economic dimensions are the weakest aspects in the advisory process, which hampers the balancing of objectives that represent one of the hallmarks of EAFM. The policy framework has adopted EAFM for European fisheries, but the advisory processes have not yet been adapted to substantially support EAFM.

Fisheries Research / 2021
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paper

Raman spectroscopy as a tool for viability assessment of planktonic organisms in UV treated ballast water

Mikkel Andreasen, Kim Lundgreen, Henrik Holbech, Martin A.B. Hedegaard*

To comply with regulations stated by the United Nation's International Maritime Organization, ballast water discharged by ships must be treated to avoid the spread of invasive organisms including algae. In this study, Raman spectroscopy and multivariate data analysis was used to make a Partial Least Squares Discriminant Analysis (PLS-DA) classification model for discrimination between viable (potential invasive) and UV exposed non-viable organisms. UV exposure is commonly used as a ballast water treatment strategy and a UV based exposure method was developed such that non-viable (and dying) algae consistently could be obtained. Raman spectra from both viable and UV treated algae of Rhodomonas salina and Tetraselmis suecica were measured. A PLS-DA model was obtained to form the normalized dataset, and Cross-Validated using Venetian blinds. Based on their individual Raman spectra, it was possible to obtain 100 % discrimination between the two algal species. The model classified 92 and 91 % of the viable algae correctly for R. salina and T. suecica, respectively, as opposed to 82 and 94 % for non-viable algae. In conclusion, in this proof of concept study, Raman spectroscopy was found to have a potential for algae species identification as well as discrimination between viable and non-viable algae.

Vibrational Spectroscopy / 2020
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Re-Analysis of Run-Up Levels for Slender Monopiles

Karsten Garborg, Thomas Lykke Andersen, Jesper Skourup & Peter Frigaard

In the present paper, the experimental data on wave run-up on slender monopiles from recently published small and large scale tests are reanalyzed using different methods for the wave analysis. The hypothesis is that the post processing has an impact on the results, due to limited depth and highly nonlinear waves in many of the tests. Thus, the identified maximum waves by a zero-down crossing analysis are highly influenced by the reflection analysis method as well as by bandpass filtering. The stagnation head theory with the run-up coefficient is adopted and new coefficients are presented. The hypothesis is verified, and the applied bandpass filter is identified as a large contributor to conservatism in previous studies, as the steep, nonlinear waves that produce the highest run-up can be heavily distorted by the bandpass filter.

International Journal of Ocean and Coastal Engineering / 2020
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Real-time deterministic prediction of wave-induced ship responses based on short-time measurements

Takami, Tomoki; Nielsen, Ulrik Dam; Jensen, Jørgen Juncher

This paper studies real-time deterministic prediction of wave-induced ship motions using the autocorrelation functions (ACFs) from short-time measurements, namely the instantaneous ACFs. The Prolate Spheroidal Wave Functions (PSWF) are introduced to correct the large lag time errors in the instantaneous sample ACF, together with a modification of the autocorrelation (AC) matrix for ensuring its positive definiteness. The validity of the PSWF-based ACFs is first examined by using the ship motion measurements from model experiment under stationary wave excitations. It is shown that the use of PSWF-based ACFs leads to better prediction accuracy than direct use of sample ACFs. The validation is then extended to ship motion prediction using in-service data from a container ship, and an improvement of the prediction accuracy by PSWF-based ACFs is again found. Finally, the effectiveness of use of the instantaneous ACFs for non-stationary wave-induced responses is highlighted by comparing with the prediction results based on the ACFs from long-time measurements.

Ocean Engineering, Volume 221 / 2021
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Real-time Deterministic Prediction of Wave-induced Ship Responses Based on Shorttime Measurements

Tomoki Takami*, Ulrik Dam Nielsen, Jørgen Juncher Jensen

This paper studies real-time deterministic prediction of wave-induced ship motions using the autocorrelation functions (ACFs) from short-time measurements, namely the instantaneous ACFs. The Prolate Spheroidal Wave Functions (PSWF) are introduced to correct the large lag time errors in the instantaneous sample ACF, together with a modification of the autocorrelation (AC) matrix for ensuring its positive definiteness. The validity of the PSWF-based ACFs is first examined by using the ship motion measurements from model experiment under stationary wave excitations. It is shown that the use of PSWFbased ACFs leads to better prediction accuracy than direct use of sample ACFs. The validation is then extended to ship motion prediction using in-service data from a container ship, and an improvement of the prediction accuracy by PSWF-based ACFs is again found. Finally, the effectiveness of use of the instantaneous ACFs for non-stationary wave-induced responses is highlighted by comparing with the prediction results based on the ACFs from long-time measurements.

Ocean Engineering / 2021
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Reconstruction of Incident Wave Profiles Based on Short-Time Ship Response Measurements

Tomoki Takami*, Ulrik Dam Nielsen, Chen Xi, Jørgen Juncher Jensen, Masayoshi Oka

This paper presents a new approach to attain estimates of the sea state based on short-time sequences of wave-induced ship responses. The present sea state estimation method aims at reconstructing the incident wave profiles in time domain. In order to identify phase components of the incident waves, the Prolate Spheroidal Wave Functions (PSWF) are employed. The use of PSWF offers an explicit expression of phase components in the measured responses and incident waves, indicating that estimations can be efficiently attained. A method to estimate the relative wave heading angle based on the response measurements and pre-computed transfer functions of the responses is also proposed. The method is tested with numerical simulations and experimental measurements of ship motions, i.e. heave, pitch, and roll, together with vertical bending moment and local pressure in a post-panamax size containership. Validation is made by comparing the reconstructed wave profiles with the incident waves. The accuracy and efficiency of the present approach are promising. At the same time, it is shown that the use of responses, which are more broad-banded in their frequency characteristics, is an effective means to cope with high frequency noise in reconstructed waves.

Applied Ocean Research / 2022
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Reduced environmental impact of marine transport through speed reduction and wind assisted propulsion

Tillig, Fabian; Ringsberg, Jonas W.; Psaraftis, Harilaos N.; Zis, Thalis

To achieve IMO’s goal of a 50% reduction of GHG emission by 2050 (compared to the 2008 levels), shipping must not only work towards an optimization of each ship and its components but aim for an optimization of the complete marine transport system, including fleet planning, harbour logistics, route planning, speed profiles, weather routing and ship design. ShipCLEAN, a newly developed model, introduces a coupling of a marine transport economics model to a sophisticated ship energy systems model – it provides a leap towards a holistic optimization of marine transport systems. This paper presents how the model is applied to propose a reduction in fuel consumption and environmental impact by speed reduction of a container ship on a Pacific Ocean trade and the implementation of wind assisted propulsion on a MR Tanker on a North Atlantic trade. The main conclusions show that an increase of the fuel price, for example by applying a bunker levy, will lead to considerable, economically motivated speed reductions in liner traffic. The case study sowed possible yearly fuel savings of almost 21 300 t if the fuel price would be increased from 300 to 1000 USD/t. Accordingly, higher fuel prices can motivate the installation of wind assisted propulsion, which potentially saves up to 500 t of fuel per year for the investigated MR Tanker on a transatlantic route.

Transportation Research Part D: Transport and Environment Volume 83 / 2020
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