Extended Operational and Trade Vocabulary
EGCS Scrubbers, SCR and Marine Air Emissions glossary (page 2)
The exhaust-treatment vocabulary: scrubber absorber towers and washwater, acid wash and demister cleaning, activated-carbon polishing for PAHs, continuous emission monitoring, and the open- and closed-loop EGCS and SCR terms. Grounds each term in the scrubber or SCR system and the MARPOL Annex VI compliance it serves.
304 defined terms.
Showing 54 on this page (page 2 of 2).
S
- Selective Non-catalytic Reduction (SNCR)
- NOx reduction technology that does not require catalyst, rarely used at sea.
- Settling tank
- Heated tank that allows water and solids to fall out before centrifuging.
- Singapore Open-loop Ban
- Prohibition on open-loop scrubber discharge in the Port of Singapore.
- Sludge tank
- Tank for engine and separator sludges.
- SO2 Monitor
- Stack analyzer measuring sulfur dioxide concentration under Scheme B.
- SO3 Aerosol
- Sulfuric acid mist formed when SO3 condenses with moisture in cool exhaust paths.
- SOx
- Oxides of sulfur, primarily SO2 with smaller fractions of SO3.
- Spray Header
- Distribution line feeding cool-down nozzles in cargo tanks.
- Spray Nozzle Wear
- Erosion and corrosion that gradually opens scrubber spray patterns and reduces efficiency.
- Stack Inlet Temperature
- Critical SCR parameter governing reaction efficiency and catalyst durability.
- Standby Bypass
- Bypass mode used while warming the scrubber prior to placing it in service.
- Static Mixer
- Inline mixing device improving urea distribution upstream of SCR catalyst.
- Sulfur Cap 0.10%
- Fuel sulfur limit in force inside SOx ECAs from 1 January 2015.
- Sulfur Cap 0.50%
- Global fuel sulfur limit in force from 1 January 2020 outside ECAs.
- Sumitomo SFA
- SCR catalyst manufacturer with marine references in collaboration with engine builders.
- Sump Tank
- Lubricating oil reservoir of an engine or pump, sometimes integrated in the bedplate.
T
- Temperature Probe
- Sensor monitoring exhaust temperature at scrubber inlet, outlet and SCR catalyst face.
- Throughput Capacity
- Maximum exhaust mass flow that an EGCS or SCR is certified to handle.
- Tier I
- NOx limit for engines on ships with keels laid on or after 2000 and before 2011 per Annex VI Reg 13.
- Tier II
- NOx limit applicable globally to engines on ships with keels laid on or after 2011.
- Tier III
- NOx limit applicable in designated NECAs to qualifying new engines.
- Turbidity Probe
- Optical sensor measuring turbidity of discharged scrubber washwater.
- Turbocharger Compatibility
- Engineering requirement when placing SCR upstream or downstream of the turbine.
- Twin-engine Scrubber
- Common arrangement where two engine uptakes share one scrubber tower.
- Type Approval Certificate
- Issued by a class society or flag administration for equipment.
U
- U-type Scrubber
- Scrubber arrangement with the exhaust path forming a U or inverted U.
- UCEM-2000
- ABB continuous emission monitoring system reference, used for SO2 and CO2 measurement.
- ULEV
- Ultra Low Emission Vessel, a market designation for ships with very low local pollutant emissions.
- Unit Certification
- Approval pathway under Scheme A based on factory-tested EGCS units.
- Urea Heating
- Trace heating maintaining urea solution above its crystallization point.
- Urea Quality
- Reductant must meet ISO 22241 or equivalent for SCR durability.
- Urea Storage Tank
- Stainless steel or coated tank carrying AUS32 or AUS40.
- US Caribbean ECA
- SOx and NOx Emission Control Area covering waters around Puerto Rico and the US Virgin Islands.
V
- Vanadium Pentoxide
- Active phase in many SCR catalysts, requiring careful handling at end of life.
- VDL AEC
- Dutch industrial supplier active in marine and industrial emission control equipment.
- Venturi Scrubber
- Scrubber design accelerating gas through a throat where washwater is injected.
- Vessel Discharge Standard
- Combined limits for pH, PAH, turbidity and nitrate in EGCS overboard discharge.
- Visible Plume
- Wet plume sometimes seen from wet scrubber outlets, primarily condensed water vapor.
- VLSFO
- Very Low Sulfur Fuel Oil with sulfur content at or below 0.5 percent mass, used to meet IMO 2020 outside emission control areas.
- Volume Flow Rate
- Washwater flow rate sized to engine power, typically 45 m3/MWh for open-loop scrubbers as a reference.
W
- Wartsila EGR
- Wartsila exhaust gas recirculation system for two-stroke engines.
- Wartsila Exhaust Gas Cleaning
- Business unit incorporating the legacy Hamworthy Krystallon scrubber portfolio.
- Wartsila NOx Reducer
- SCR product family from Wartsila for medium-speed and two-stroke engines.
- Wash Tower
- Synonym for the absorber column of a wet scrubber.
- Washwater Discharge Criteria
- pH, PAH, turbidity and nitrate limits set in MEPC.340(77).
- Washwater Monitoring System
- Instrumentation chain measuring discharge water properties.
- Washwater Treatment Unit
- Skid removing solids and dissolved contaminants from scrubber bleed-off.
- Well-to-wake
- Lifecycle accounting boundary used in FuelEU Maritime greenhouse gas intensity.
- Wet Scrubber
- EGCS using liquid contact to remove SOx from the exhaust.
X
- X-flow Demister
- Cross-flow demister arrangement used in some compact scrubber towers.
Y
- Yara Marine Technologies
- Supplier of SCR, scrubbers, and (with BAR) WindWings.
- Yara NOxReducer
- Yara Marine Technologies SCR product line for marine diesel engines.
Z
- Zero discharge mode
- Operation with no discharge to sea.
- Zone Restriction
- Geographic limitation on EGCS operation, fuel sulfur or NOx emissions.