SLIDE 25 EGCS Pros Cons Application
Open Loop
- Uses seawater for scrubbing; does not
usually involve storage or handling of hazardous chemical (caustic soda)
- Comparatively simple system; less
equipment/system compared to closed loop
- CAPEX and OPEX relatively low
- Not suitable for low alkalinity water
- Restriction of washwater discharge in certain
coastal/port areas
- Large washwater demand
- Vessels operating most
- f the time in the
- cean/open sea.
- Vessels not entering
areas with washwater discharge restriction.
Closed Loop
- Independent of operation location –
in low alkalinity water; in discharge restricted coastal/port areas
- Effluent is stored onboard for the
duration that the tank volumes will permit
- Complex washwater system
- Additional equipment/system for water treatment
- More space required
- Special care for handling and storage of NaOH
solution, a hazardous substance.
- Operation duration limited by effluent tank
size
- Relatively higher CAPEX
- Relatively higher OPEX due to use of NaOH and
residue handling
constantly in areas with discharge restriction or low alkalinity Water
Hybrid
- Significant flexibility for operating in
all regions regardless of seawater alkalinity or temperature
- Effluent may be stored onboard for
the duration that the tank volumes will permit
- Complicated system with more components
- More space required
- Handling and storage of NaOH, and residue
disposal for closed mode operation
- Highest CAPEX
- Higher OPEX due to use of NaOH and residue
handling
sea and discharge/
areas
EGCS - INTRODUCTION
