Selective Catalytic Reduction Operation with Heavy Fuel Oil: NOx, NH3, and Particle Emissions
- 26 March 2015
- journal article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 49 (7), 4735-4741
- https://doi.org/10.1021/es506185x
Abstract
To meet stringent NOx emission limits, selective catalytic reduction (SCR) is increasingly utilized in ships, likely also in combination with low-priced higher sulfur level fuels. In this study, the performance of SCR was studied by utilizing NOx, NH3, and particle measurements. Urea decomposition was studied with ammonia and isocyanic acid measurements and was found to be more effective with heavy fuel oil (HFO) than with light fuel oil. This is suggested to be explained by the metals found in HFO contributing to metal oxide particles catalyzing the hydrolysis reaction prior to SCR. At the exhaust temperature of 340 °C NOx reduction was 85-90%, while at lower temperatures the efficiency decreased. By increasing the catalyst loading, the low temperature behavior of the SCR was enhanced. The drawback of this, however, was the tendency of particle emissions (sulfate) to increase at higher temperatures with higher loaded catalysts. The particle size distribution results showed high amounts of nanoparticles (in 25-30 nm size), the formation of which SCR either increased or decreased. The findings of this work provide a better understanding of the usage of SCR in combination with a higher sulfur level fuel and also of ship particle emissions, which are a growing concern.This publication has 24 references indexed in Scilit:
- Impact of maritime transport emissions on coastal air quality in EuropeAtmospheric Environment, 2014
- Design of Durable Vanadium - SCR Catalyst Systems for Heavy - Duty Diesel ApplicationsSAE International Journal of Advances and Current Practices in Mobility, 2013
- The influence of sulfur dioxide and water on the performance of a marine SCR catalystApplied Catalysis B: Environmental, 2012
- Effectiveness of Emission Control Technologies for Auxiliary Engines on Ocean-Going VesselsJournal of the Air & Waste Management Association, 2011
- Mortality from Ship Emissions: A Global AssessmentEnvironmental Science & Technology, 2007
- Emissions from international shipping: 1. The last 50 yearsJournal of Geophysical Research: Atmospheres, 2005
- Environmental catalysis for stationary applicationsCatalysis Today, 2000
- Improved SCR Systems for Heavy Duty ApplicationsSAE International Journal of Advances and Current Practices in Mobility, 2000
- Chemical and mechanistic aspects of the selective catalytic reduction of NOx by ammonia over oxide catalysts: A reviewApplied Catalysis B: Environment and Energy, 1998
- Recent Advances in De‐NOxing Catalysis for Stationary ApplicationsHeterogeneous Chemistry Reviews, 1996