EXHAUST GAS DENITRATION SYSTEM, SHIP WITH EXHAUST GAS DENITRATION SYSTEM, AND EXHAUST GAS DENITRATION SYSTEM CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To suppress a change in an exhaust gas flow introduced to an exhaust turbocharger depending on whether to perform denitration.SOLUTION: An exhaust denitration system includes: an exhaust turbocharger 5 driven by exhaust gas from a ship diesel engine 3; a reactor 2 producing ammonia from urea water; a urea-water injection nozzle 32 supplying the urea water into the reactor 2; an SCR catalyst unit 4 provided in an exhaust gas passage downstream of the exhaust gas turbocharger 5, and performing exhaust gas denitration using the ammonia supplied from the reactor 2; an exhaust gas bypass passage B1 introducing exhaust gas obtained by extracting part of the exhaust gas supplied to the exhaust gas turbocharger 5 from the diesel engine 3; and a power turbine passage 71 provided in parallel and switchably to/from the exhaust gas bypass passage B1, and provided with a power turbine 70 driven by the exhaust gas to generate electric power.