Royal Caribbean has embarked upon an environmental initiative to reduce its cruise ship emissions by 2017, called Advanced Emissions Purification (AEP).
The program is underway and scheduled for completion in 2017 and will see the installation of so-called exhaust “scrubbers” on 13 Royal Caribbean ships.
Put most simply, AEP works by spraying diesel exhaust with fine mist from a ring of water jets. As the mist combines with sulphur dioxide it creates sulphuric acid. In a happy coincidence, seawater is naturally alkaline so it neutralizes the sulphuric acid to a degree that meets strict water discharge standards after the wastewater is centrifuged to remove toxic particulates.
In some of the areas where RCL ships sail, alkaline levels in the seawater are too low to be effective. So the company opted for hybrid AEP systems allowing ships to switch as necessary between an “open loop” of untreated seawater to a “closed loop” system that boosts alkalinity with the addition of caustic soda.
The work will be done on some ships during scheduled drydocks and on others while the ship is in service.
The AEP systems being installed are manufactured by Wärtsilä of Finland and Alfa Laval of Sweden.