How to select the denitration nozzle, the core component of the SNCR denitration system

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As a key component in the SNCR denitration process, the proper selection of denitration nozzles is crucial in order to ensure that the denitration system achieves optimal efficiency. This is the primary consideration when using the SNCR denitration process. When selecting a denitration spray gun, it is necessary to consider the following aspects. I. Material: Since the denitration spray gun requires injecting corrosive reducing agents into the boiler furnace at temperatures of 850°C–1050°C during use, materials that are resistant to corrosion and high temperatures must be employed. Furthermore, the rapid movement of dust in the flue gas during flue gas denitration can cause wear on the denitration nozzles; therefore, the wear resistance of the nozzle material also needs to be taken into consideration. II. Atomization effect: The atomization effect of denitration nozzles mainly includes the particle size of the atomized particles and the coverage area of the atomization. The particle size of the mist generated by the denitration nozzle should be moderate – it cannot be too large nor too small. When the particle size is too large, the spray particles cannot come into sufficient contact with the flue gas, which affects the denitration efficiency; in severe cases, failure to vaporize completely results in the formation of liquid droplets, leading to tube explosions in the furnace ； When the particles are too small, their penetration ability is poor, thereby reducing the denitration efficiency. In addition, the adjustment capability of the denitration nozzle also needs to be considered. Denitration nozzles generally come in two installation types: fixed and telescopic. For denitration systems that are used intermittently, the telescopic installation option can be employed; by retracting the nozzle out of the furnace when it is not in use, its service life can be extended ； For spray guns chosen for fixed installation, a protective cover can be installed on the nozzle section to ensure their long-term effective use.