Maritime Glossary
Exhaust Gas Cleaning System
Also known as: EGCS, scrubber, open-loop scrubber, closed-loop scrubber, hybrid scrubber
A shipboard system that removes sulphur oxides from engine exhaust gas, enabling compliance with MARPOL Annex VI sulphur limits while burning HFO.
Full Definition
An EGCS (scrubber) sprays water through the exhaust stream to absorb SOx and particulates. Open-loop scrubbers discharge sulphate-laden washwater overboard (banned in some ECAs and port areas). Closed-loop scrubbers recirculate washwater internally with only a small treated bleed stream discharged. Hybrid scrubbers can operate in either mode. EGCS approval requires compliance with IMO MEPC.259(68) guidelines. Scrubbers allow continued HFO use in ECAs, but washwater quality is subject to increasing port-state scrutiny.