35 t/h燃煤锅炉烟气喷淋降温的数值模拟

Numerical Simulation of Spraying Cooling on a 35 t/h Coal Fired Boiler

喷淋降温是控制燃煤锅炉烟气温度的有效工艺,该研究针对某热电厂的35 t/h燃煤锅炉进行了喷淋降温的建模和模拟计算。首先针对2种自主产权的喷枪、喷枪的分布方式和喷枪的分布位置进行比较研究,研究发现单孔喷枪在Z=3 m处进行分散式分布最为合理。在确定喷淋降温基本参数的基础上,考察了喷淋液滴直径、喷枪用水温度、喷枪水流量对喷淋降温的影响。研究发现喷枪用水温度对喷淋降温影响不大,但喷淋液滴直径和喷枪水流量对喷淋降温则有较大影响。当液滴直径从0.08 mm增加到0.42 mm,进出口烟气的温差从35.55℃下降到20.44℃。当喷枪流量从0.02 kg/s增加到0.07 kg/s,进出口烟气的温差从12.55℃上升到37.82℃。

With the contribution of CFD method,the numerical simulation of spay cooling of a 35 t/h boiler was carried out in this study.Firstly,the effects of different spraying lances,distribution mode of spraying lances and location of spraying lances on the spraying cooling were studied.The results showed that,single-hole spraying lances worked better than two-holes spraying lances did.Moreover,the suitable position of single-hole spraying lances were located at Z=3 m.Based on the above researches,we studied the influences of diameters of the droplets,water temperature and water flow rate on spraying cooling.The results indicated that the water temperature had little effect on spraying cooling.However,the diameters of the droplets and the water flow rate had great effect on spraying cooling.When droplet diameter changed from 0.08 mm to0.42 mm,the temperature drop decreased from 35.55℃to 20.44℃.When water flow changed from 0.02 kg/s to 0.07 kg/s,the temperature drop increased from 12.55℃to 37.82℃.