MARITIME EXHAUST GAS DENITRATION DEVICE

Provided is a marine-exhaust-gas denitration device with which the fuel consumption by heating means can be suppressed, and the running cost can be reduced. Included are a reducing-agent storage tank (11) that stores a reducing agent; a reducing-agent injection nozzle (13) from which the reducing agent stored in the reducing-agent storage tank (11) is jetted into the exhaust gas; a denitration reactor (14) provided with a catalyst that reduces the nitrogen oxides contained in the exhaust gas; heating means (15), provided on the upstream side of the denitration reactor (14), for increasing the temperature of the exhaust gas to be supplied to the denitration reactor (14); and a control device (16) having functions for activating the heating means (15) when the performance of the denitration reactor (14) drops below a predetermined level to increase the temperature of the exhaust gas to be supplied to the denitration reactor (14) and for stopping the heating means (15) when the performance of the denitration reactor (14) subsequently exceeds the predetermined level to stop an increase in the temperature of the exhaust gas to be supplied to the denitration reactor (14).