EGCS

An Exhaust Gas Cleaning System is the IMO term for a marine SOx scrubber, accepted under MARPOL Annex VI Reg.4 as an equivalent means to using low-sulphur fuel. The 2020 EGCS Guidelines (MEPC.340(77)) set washwater discharge criteria on pH, PAH, turbidity, and nitrates, plus continuous monitoring. Open-loop, closed-loop, and hybrid configurations differ in washwater handling. Adoption rose sharply before the 2020 sulphur cap among ships burning high-sulphur fuel, but tightening local discharge bans and the long-term shift to compliant fuels and alternative fuels limit its future role.