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TI - Evaluation of a Modern Tier 2 Oceangoing Vessel Equipped with a Scrubber
AU - Johnson, K
AB - Emissions from marine engines (container vessels, crude tankers, bulk cargo, auto carrier, cruise ships, and other ocean-going vessels) represent a significant contribution of particulate matter (PM), sulfur oxide (SOx) and nitrogen oxide (NOx) emissions where marine engines represents 15% of global anthropogenic NOx and 5-8% of the global SOx emissions (Viana M. et al 2014, Eyring V. et al 2005). To control SOx emissions from marine engines, Annex VI regulations include caps on the sulfur content of fuel oil which indirectly also reduces PM emissions. However, the International Maritime Organization (IMO) does not have any explicit PM emission limits. Providing the vessel meets the applicable sulfur limit (0.1% within the emissions control area (ECA) and 0.05% outside the ECA), HFO is allowed if alternative technology is used to limit SOx emissions to a fuel equivalent 0.1% sulfur (S). Scrubbers, or other exhaust gas cleaning systems, are alternatives to using 0.1% S fuel. Scrubber technology is designed to reduce SOx emissions and has the potential to reduce PM2.5 emissions. It is of interest to the California Air Resources Board (CARB) to quantify the in-use emissions control effectiveness on emissions from scrubber technology. The scrubber evaluated was a Wärtsilä hybrid wet scrubber system designed to operate in both open loop mode (using seawater to remove SOx from the exhaust gas), and in closed loop mode (reagent is used in combination with sea water to remove SOx from the exhaust gas). The scrubber was operated in open loop mode for this testing where in previous scrubber evaluations it has been demonstrated closed loop and open loop emission reductions are similar (Johnson et al 2016). The test loads utilized were based on ISO-8178 E3 and D2 protocols for the main engine (ME) and diesel generators (DG), respectively. Emissions were measured for gaseous, PM2.5 (total mass, elemental, organic carbon, and sulfated species, but not metals), and particle size distribution (PSD), following ISO and Code of Federal Regulations (CFR). In addition, upgrades were performed to meet 40 CFR Part 1065 dilution ratios and filter temperatures on an exhaust that was cooled with sea water. The primary aim of this work is to study the in-use emissions from a modern Tier 2 OGV equipped with a scrubber while operating on 2.5% sulfur Heavy Fuel Oil (HFO). Emissions measurements were made before and after the scrubber at load points of 33%, 50%, and 75% for the ME and 50% for the DG. The analysis presented is based on the combined exhaust of the ME and DG through the scrubber system. The measured combined weighted emission reductions across the scrubber were 97% for sulfur dioxide (SO2) and 6% for the organic carbon (OC) PM species where the rest of the PM increased across the scrubber (PM2.5 4%, EC 12% and 5% for Sulfate, see Table ES-1). PM2.5 emissions pre-and post-scrubber ranged from about 1.0 to 1.3 g/kWhr where there was not an observed PM reduction resulting from the scrubber. Other studies show switching from HFO to a low sulfur marine gas oil (MGO) can have a 75% reduction in PM2.5 emissions (Kahn et al 2012). This suggests scrubbers may not be effective in reducing total PM even though they meet the requirements of IMO.
DA - 2018/01//
PY - 2018
SP - 79
UR - https://ww2.arb.ca.gov/sites/default/files/2022-01/UCR%20Tanker%20Boiler_v05%20Final.pdf
LA - English
KW - Unspecified Feedstock
KW - Heavy Fuel Oil (HFO)
KW - Unspecified Pathway
KW - Engine Testing and Performance
KW - Lifecycle Assessment (LCA) and Air Emissions
KW - Ocean-going Vessels
ER -
Abstract
Emissions from marine engines (container vessels, crude tankers, bulk cargo, auto carrier, cruise ships, and other ocean-going vessels) represent a significant contribution of particulate matter (PM), sulfur oxide (SOx) and nitrogen oxide (NOx) emissions where marine engines represents 15% of global anthropogenic NOx and 5-8% of the global SOx emissions (Viana M. et al 2014, Eyring V. et al 2005). To control SOx emissions from marine engines, Annex VI regulations include caps on the sulfur content of fuel oil which indirectly also reduces PM emissions. However, the International Maritime Organization (IMO) does not have any explicit PM emission limits. Providing the vessel meets the applicable sulfur limit (0.1% within the emissions control area (ECA) and 0.05% outside the ECA), HFO is allowed if alternative technology is used to limit SOx emissions to a fuel equivalent 0.1% sulfur (S). Scrubbers, or other exhaust gas cleaning systems, are alternatives to using 0.1% S fuel. Scrubber technology is designed to reduce SOx emissions and has the potential to reduce PM2.5 emissions. It is of interest to the California Air Resources Board (CARB) to quantify the in-use emissions control effectiveness on emissions from scrubber technology. The scrubber evaluated was a Wärtsilä hybrid wet scrubber system designed to operate in both open loop mode (using seawater to remove SOx from the exhaust gas), and in closed loop mode (reagent is used in combination with sea water to remove SOx from the exhaust gas). The scrubber was operated in open loop mode for this testing where in previous scrubber evaluations it has been demonstrated closed loop and open loop emission reductions are similar (Johnson et al 2016). The test loads utilized were based on ISO-8178 E3 and D2 protocols for the main engine (ME) and diesel generators (DG), respectively. Emissions were measured for gaseous, PM2.5 (total mass, elemental, organic carbon, and sulfated species, but not metals), and particle size distribution (PSD), following ISO and Code of Federal Regulations (CFR). In addition, upgrades were performed to meet 40 CFR Part 1065 dilution ratios and filter temperatures on an exhaust that was cooled with sea water. The primary aim of this work is to study the in-use emissions from a modern Tier 2 OGV equipped with a scrubber while operating on 2.5% sulfur Heavy Fuel Oil (HFO). Emissions measurements were made before and after the scrubber at load points of 33%, 50%, and 75% for the ME and 50% for the DG. The analysis presented is based on the combined exhaust of the ME and DG through the scrubber system. The measured combined weighted emission reductions across the scrubber were 97% for sulfur dioxide (SO2) and 6% for the organic carbon (OC) PM species where the rest of the PM increased across the scrubber (PM2.5 4%, EC 12% and 5% for Sulfate, see Table ES-1). PM2.5 emissions pre-and post-scrubber ranged from about 1.0 to 1.3 g/kWhr where there was not an observed PM reduction resulting from the scrubber. Other studies show switching from HFO to a low sulfur marine gas oil (MGO) can have a 75% reduction in PM2.5 emissions (Kahn et al 2012). This suggests scrubbers may not be effective in reducing total PM even though they meet the requirements of IMO.