Vessel exhaust gas denitration system and method of determining nozzle clogging in the same

An exhaust gas vessel denitration system, comprising:

• an exhaust pipe for discharging exhaust gas including nitrogen oxide generated from an engine;
• an urea tank for storing urea;
• an injecting module including a pulse type injector for mixing the urea with heated air to generate a reducing agent and spraying the reducing agent to the exhaust pipe according to a pulse signal;
• a rotation number adjusting-type pump for supplying the urea stored in the urea tank to the injecting module and connected to the injecting module to be operatively associated to the injecting module to control a supply amount of the reducing agent;
• a reducing agent inlet including a pressure transmitter for monitoring pressure of the reducing agent between the injecting module and the pump;
• a reactor for inducing a reduction reaction of exhaust gas mixed with the reducing agent and decomposing nitrogen oxide in the exhaust gas to nitrogen and water vapor to reduce the nitrogen oxide,
• wherein the reducing agent inlet is configured in such a way that the injecting module, the pump, and the pressure transmitter are formed as a module in an integrated dosing unit (IDU) that is one physical space.