EXHAUST GAS PURIFYING SYSTEM FOR VESSEL ENGINE

摘要

A vessel is loaded with a general fuel (C-heavy oil) tank (3) and a low-sulfur fuel (A-heavy oil) tank (4).  In the exhaust line of an engine (1), an SCR catalyst (10) of a urea water spray type is arranged and a bypass exhaust pipe (16) in which the exhaust gas passes not through the SCR catalyst (10) is also arranged.  An automatic vessel-position detecting means (B) and a restriction map are collated to compute the distance to the sea area of a restriction target automatically.  On the arrival at the restriction-target sea area, the function of the SCR catalyst (10) is stopped by changing the fuel automatically from the general fuel to the low-sulfur fuel and by discharging the exhaust gas to the bypass exhaust pipe (16).  The change of the exhaust gas purifying state is automatically made.