重油とスクラバーによる海上輸送の環境影響評価（Study:Burning Heavy Fuel Oil with Scrubbers Best for Bulk Maritime Shipping）

2025-04-11

2025-04-04 ジョージア工科大学

ジョージア工科大学とMITなどの研究チームは、重油（HFO）を使用しスクラバーで排ガスを浄化する方法が、バルク海上輸送において最も環境負荷の少ない選択肢であることを、ライフサイクルアセスメント（LCA）により明らかにしました。この研究は、燃料の生産から使用、排出までの全過程を評価し、温室効果ガス排出や酸性化、オゾン生成など10の環境影響指標において、HFO＋スクラバー方式が他の選択肢より優れていることを示しています。特に、スクラバーは硫黄酸化物の排出を97％削減し、洗浄水中の有害物質濃度も国際基準を大幅に下回っていました。この成果は、国際海事機関（IMO）の規制や政策決定に科学的根拠を提供し、持続可能な海上輸送の実現に貢献することが期待されます。

＜関連情報＞

舶用スクラバーと低硫黄燃料の比較海洋航行船上での測定に裏付けられた包括的な航続距離ライフサイクル評価 Marine Scrubbers vs Low-Sulfur Fuels: A Comprehensive Well-To-Wake Life Cycle Assessment Supported by Measurements Aboard an Ocean-Going Vessel

Patritsia M. Stathatou,Ievgenii Petrunia,Torsten Barenthin,George Gotsis,Paul Jeffrey,Christopher Fee,Scott Bergeron,Marios Tsezos,Michael Triantafyllou,and Neil Gershenfeld
Environmental Science & Technology Published: April 4, 2025
DOI:https://doi.org/10.1021/acs.est.4c10006

Abstract

Maritime transport significantly contributes to global emissions, prompting the International Maritime Organization to implement stricter regulations to reduce pollution. Since 2020, fuel sulfur (S) content limits have been reduced, requiring either the use of low-S fuels or the installation of marine scrubbers to continue using heavy fuel oil (HFO). While scrubbers are a widely adopted solution for reducing S emissions, their benefits are controversial and uncertainty remains regarding scrubber environmental impacts and their appropriate evaluation. Here, we systematically assess the environmental impacts of scrubbers operating on HFO to those of low-S fuels across various categories, through a measurement-informed Well-to-Wake (WtW) life cycle assessment (LCA). Gaseous and particulate matter (PM) emissions data were collected while a bulk carrier vessel was burning 3% S HFO, 0.1% S marine gas oil (MGO), and 0.5% S very low-S fuel oil (VLSFO) under similar engine operating modes during an actual ocean voyage. Seawater and washwater samples were also analyzed, alongside fuel, cylinder oil, and lubricant samples. The results suggest that, in various instances the use of HFO with a scrubber can be considered equivalent to MGO use while outperforming VLSFO use from a WtW perspective, for large, ocean-going bulk carrier vessels in open seas. These findings indicate that end-of-pipe solutions may not always be inferior to start-of-pipe alternatives, underscoring the need for comprehensive LCA studies to properly assess emission abatement technologies.