Green Shipping—Multifunctional Marine Scrubbers for Emission Control: Silencing Effect

Giada Kyaw Oo D’Amore,Marco Biot,Francesco Mauro,Jan Kašpar

doi:10.3390/app11199079

Giada Kyaw Oo D’Amore, Marco Biot + Show 2 more

Open Access

https://doi.org/10.3390/app11199079

Copy DOI

Abstract

Scrubber systems abate the sulphur oxide emissions of engines when cheap fuel oils that are high in sulphur content are employed as combustibles. However, the ships with these voluminous devices installed on board is space demanding. This work analyses the feasibility of incorporating the acoustic abatement of the exhaust gas noise functionality into the scrubber design to provide a combined scrubber–silencer system. For this purpose, a finite element analysis is performed on a simple expansion chamber, which is assessed using both analytical and experimental data. The transmission loss is the acoustic parameter chosen in this work. The numerical model depicts a good correlation with the transmission loss measured on a model scale scrubber. Finally, scrubber geometry modifications alter the transmission loss, changing and/or enhancing its featuring. These abilities indicate the feasibility to confer to scrubber silencing effects.

Highlights

Introduction maritime transport accounts for approximately 10–15% of global sulphur (SOx) and nitrogen (NOx) oxide emissions, the volume of seaborne trade has increased by about 3% annually over the past 50 years or so, accounting for about 80–85% of world trade by volume [1]. This has led to increasing concerns about the global impact of maritime emissions, and, consistently, the IMO (International Maritime Organization) has restricted the limits imposed by MARPOL 73/78 Regulations [2,3] on ship emissions, those of SOx [3] and NOx [2]
Different strategies allow for SOx emissions to be reduced [6]: alternative fuels (e.g., LNG—liquefied natural gas), alternative energy sources, and conventional fuels with low a sulphur content (e.g., VLSFO—very low sulphur fuel oil)
Since January 2020, for ships using conventional fuels, the above-quoted regulations have made the use of VLSFO mandatory, as its sulphur content is lower than 0.5 wt%

Summary

Introduction

Maritime transport accounts for approximately 10–15% of global sulphur (SOx) and nitrogen (NOx) oxide emissions, the volume of seaborne trade has increased by about 3% annually over the past 50 years or so, accounting for about 80–85% of world trade by volume [1]. EGR (exhaust gas recirculation) and SCR (selective catalytic reduction) systems are recognized as effective technologies for the control of marine NOx emissions [1,4] The former solution increases particulate matter emissions and fuel consumption by about 4% [5], making SCR the preferred option. Scrubbers represent a viable solution [8] and show a lower climate impact than low sulphur fuels [9]

Methods

Results

Conclusion