Performance evaluation device and performance evaluation method of coal-fired flue gas denitration catalyst

The invention provides a performance evaluation device and a performance evaluation method of a coal-fired flue gas denitration catalyst. The device comprises gas paths I-VI, a pressure reducing valve, a pressure stabilizing valve, a permanent flow valve, a pressure meter, a mass flow meter, a water vapor generator, a check valve, a three-way valve, a tee joint, a cross joint, a gasification chamber, a six-way joint, a quartz reaction pipe, a heating furnace, a thermocouple, a temperature controller, a gas filter, a mass spectrometer and a computer. According to the device, the six-way joint is introduced, so that the modes of purging gas and reaction gas can be conveniently switched, the pretreatment process of a catalyst sample and the mixing and preheating steps of reaction gas can be implemented simultaneously, further the time is saved, and the test efficiency is improved; the mass spectrometer can be used for detecting the full components of the reaction gas and product molecules, information such as N2 selectivity can be effectively given through N element conservation calculation, and the problem of the generation of room-temperature gas N2O due to neglecting can be solved. According to the evaluation method, the contribution of the reaction gas NH3 to N2 can be sufficiently considered.