Three papers providing: lab analysis of 99+146 ship samples taken from 12 ships per ISO standards and proposing standard calculation method for emission factors; consideration of the origin of elevated copper and zinc readings from sea chests; and a SINTEF QA review of emissions calculations.
Uses 99 directly gathered inlet water samples and 146 discharge samples to support the calculation of emission factors, establishing a practical method and resultant set of credible emission factors.
Compares laboratory analysis of 281 EGCS washwater samples from 53 ships in global operations with major national and international water quality standards
Used standard US EPA sampling and lab analysis protocols, analyzed for 54 parameters: washwater met all regulatory and major national/international standards, including WHO drinking water and EU WFD Environmental Quality Standards (EQS).
Literature review and modeling to assess risk of EGCS discharges, includes 11 locations based on shipping activity and proximity to sensitive ecological areas. Estimates high concentrations of discharges and uses MAMPEC for end fates.
Scrubber discharges are expected to have negligible effects in shipping lanes and in Milford Sound, and low to moderate risks of potential effects in select ports
Long-term ecosystem impacts of open-loop EGCS washwater discharges in a harbour port modelled and evaluated, with copper identified as a limiting contaminant. A 3D hydrodynamic and advection-dispersion model was used to evaluate the mixing and accumulation of effluent and contaminants from EGCS discharges over time from ships, using a conservative worst case scenario.
Modeling of long-term impacts of shipping washwater contaminants on harbour ecosystem health indicate that the EGCS washwater contaminant inputs will make a negligible contribution to any exceedance of water quality guideline values (WQGV) and have negligible impacts on harbour ecosystem health.
The Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) Task Team on EGCS was convened by MEPC to provide an opinion on the potential environmental and public health effects of EGCS effluent.
Ecotoxicity: Found only 1 of 10 studies evaluated was using standard ISO or USEPA methods/protocols, with no adverse effects. Concluded that any effects would likely be from washwater pH, though sufficiently mitigated by normal seawater dilution.
Reports on the analysis of 238 samples of scrubber overboard discharges and of seawater from 20 vessels in the Baltic and North Sea ECAs and two vessels in the Mediterranean in a joint campaign run by EGCSA and Euroshore.
Substantial direct sampling dataset, test procedures generally aligned with MEPC.1/Circ.899. The toxic metals (lead, cadmium, mercury, arsenic) were largely undetected. Some nitrates were detected, at levels well below IMO limits, but nitrites were undetected.
Compares empirical data from almost 300 washwater samples to EU WFD water quality standards and evaluates the impacts of open loop EGCS on water and sediments in several N. European modelled ports.
For most ports and substances, the increase in concentrations is less than 0.1% of the limit values in the new EQS standards, easily meeting EU WFD water quality standards. Also, accumulation in sediment over decades remains a small percentile of the limits.
Evaluates risk to the marine environment from metals, PAH’s and reduced pH discharges in high traffic areas of the Kattegat and Bight of Aarhus.
Modeling and comparison with EU EQS show EGCS discharge levels of metals/PAH’s to be orders of magnitude below the levels of ecological concern, and with negligible risks from acidic discharges.
a) Botnen, et al (1991), Field benthic survey and sampling evaluating environmental impact of Mongstad scrubber discharges
b) Nyman & Tokerud (1991), Mongstad seawater scrubber first year of operation, Oil and Gas Journal
c) Johansen, Heggoy (2009), Monitoring of marine biological conditions at Statoil’s production facilities at Mongstad in 2009
These reports provide results from on-site surveys, which have been regularly conducted since 1990, with water and marine plant and animal sampling and sample analysis from around the discharge point of the seawater scrubb
No significant changes in the animal and plant life at Mongstad have been registered that can attributed to the operation of the facilities. The environment at the bottom stations is still considered good; the benthic fauna in March 2009 remains very rich in species as before and the fauna composition was relatively similar to that as before. The concentrations of oil hydrocarbons in the sediment were low and have decreased to the same level as in 2000. The content of most aromatic hydrocarbons was also still low in sediment. The concentrations of heavy metals in mussels were generally low.
Marine scrubbers vs low-sulphur fuels: A comprehensive well-to-wake life cycle assessment supported by measurements aboard an ocean-going ship to assess environmental impacts.
Finds that the Well-to-Tank impacts of HFO+ECGS were lower than MGO or VLSFO across all categories, including CO2: also, no risk of eutrophication and no likely adverse effects from EGCS discharges on receiving water bodies and ecosystems.
Risk assessment used discharge water sample analysis and computational modeling to measure the ecological impacts of EGCS used by ships while traveling the Asia/Brazil route, as well as berthed or navigating through the Port of Tubarão in Brazil.
Models at different power levels found accumulations of metals in the water column and sediments were well under limits, and that EGCS discharges may be safely carried out without violating national water or sediment standards.
Comprehensive assessment by Oregon State University and research group EcoAnalysts; washwater samples were gathered from 6 ships transiting Puget Sound and lab analysis and WET testing were conducted using standard US EPA/ISO methods per IMO Guidelines.
Combined chemical analysis, comparison to water quality standards, predictive models for PAH’s, WET testing, and dispersion modeling for both port and transits scenarios found the risk was very low in Puget Sound, with an RCR < 1.
Installed and operated a test open loop EGCS unit to measure and evaluate components of the discharge water, using standard ISO and US EPA protocols.
In the environmental risk assessment, phenanthrene was judged as a persistent bioaccumulative and toxic substance, but the environmental risk is low as there were no substances with RCR values > 1. In summary, the environmental risk posed by open-loop EGCS discharge water is not considered high.
WET testing of marine organisms using EGCS discharge water samples from 4 ships operating in N.Europe, using generally accepted methods and IMO guidelines, and arriving at a risk characterization ratio. Used conservative assumptions to model three restrictive environments.
Analysis from MAMPEC modeling and WET testing found a risk characterization ratio (RCR) of < 1, meaning risk to the marine environment is considered acceptable (i.e. negligible).
Japanese Government evaluated both short and long-term environmental risks caused by discharge water from EGCS to the marine environment, conducting WET testing aligned with MEPC Guidance and using actual scrubber washwater.
Concludes that the discharge water cannot cause unacceptable effects to the marine environment, aquatic organisms, or marine water quality. Finds that there is no scientific justification for restricting open loop EGCS use.
Investigates whether natural coastal bacterioplankton communities can rapidly biodegrade polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs present in scrubber effluent discharged from ships.
PEC/PNEC, field validation, RCR applied.
Finds significant effects on PAH reduction from microbes; rapid biodegradation of PAH by native bacterioplankton communities removed over 85% of PAHs and alkyl-PAHs within 3 days. Further offshore reduction was slower, with 50% reduction in 6 days.
Evaluates how open-loop EGCS discharge impacts natural metazooplankton communities (vs. single species) particularly copepods in a coastal Mediterranean setting. Two exposure scenarios, a low and a high scrubber discharge (1% and 10% dilution) were considered.
High exposure scenario showed some effects; however the low exposure scenario showed no effects on copepod development or abundance, supporting the conclusion that typical dilution scenarios in open waters pose negligible risk under real-world conditions.
A fully integrated comparison of CO2 emissions conducted on a well-to-wake (lifecycle) basis, with all GHG emissions over the lifecycle of compliance options (EGCS /HFO, VLSFO, & MGO) considered.
Found that due to the typical refining and desulphurization processes producing low sulphur fuels, that the use of EGCS plus heavy fuel oil (HFO) produces significantly lower CO2 emissions to atmosphere than using very low sulfur fuel oil (VLSFO) or marine gasoil (MGO).
Describes marine diesel engine exhaust components and various particulate types, sizes and effects on health, and the effectiveness of various reduction techniques, including fuel efficiency measures, fuel types, WIFE, EGCS, WESP, DPF’s (diesel particulate filters) and DOC’s (diesel oxidation catalysts.
Both the use of low sulphur fuels and EGCS proved to be effective in reducing PM with size as low as 500 nm. Specific PM emissions were generally higher for IFO/HFO than for MGO; however, for the smallest size-fraction measured MGO was higher. Soot fractions of EC and OM could not be reduced by changing the sulphur level in the diesel fuels.
Conducts measurements of exhaust gases and particulates from a marine engine equipped with an open-loop scrubber using seawater for SO2 abatement, reducing SO2 to levels corresponding to IMO requirements of <.01% of sulphur in fuel.
The scrubber reduces particulates by mass by 75%, with the total particle number reduced by about 92% and the solid fraction by 48%. This reduction of PM’s is of the same order as what is obtained with a switch of fuels from HFO to MGO.
PAH’s are also significantly reduced.