Measurement of Sulfur-Dioxide Emissions from Ocean-Going Vessels in Belgium Using Novel Techniques

Abstract

Air pollutants emitted by ocean-going vessels (OGVs) cause numerous environmental and human health problems. In 2016, the Belgian Coastguard aircraft was equipped with a sniffer sensor to monitor compliance with MARPOL Annex VI Regulation 14. However, the sensor was susceptible to NO and Volatile Organic Compounds (VOCs), which had a negative impact on the measurement uncertainty. The elimination of measurement errors was achieved by modifying the sensor, including among others the addition of a NOx sensor and a custom-designed hydrocarbon kicker. This resulted in a substantial improvement in the measurement quality and uncertainty of the derived Fuel Sulfur Content (FSC). As a direct result of this, the reporting thresholds for non-compliance drastically improved. The data analysis of sampled OGVs showed that compliance levels notably improved between 2019 and 2020 (from 95.9% to 97.3%), coinciding with the implementation of the Global Sulfur Cap. Findings in this study have also demonstrated that OGVs equipped with emission abatement technology (scrubbers) are more susceptible to non-compliance with Regulation 14 of MARPOL Annex VI. Given these results, this article provides an answer to the question of how to monitor effective implementation of NO emissions from OGVs.

Keywords

• airborne compliance monitoring
• MARPOL Annex VI
• SECA
• scrubbers
• sulfur-dioxide