660 MW燃煤电厂SNCR脱硝数值模拟

Numerical Simulation of SNCR Denitration in 660 MW Coal-Fired Power Plant

研究选择性非催化还原脱硝法(SNCR)在大型燃煤电厂运行的影响因素,使用计算流体力学软件CFD模拟炉内喷入以尿素为还原剂的脱硝过程。模拟结果发现锅炉处于满负荷运行时,炉膛顶部满足SCNR脱硝温度窗口的高度为57 m以上,因此使用三区、五区、六区的尿素溶液喷枪。随着氨氮比的增加,脱硝率从25.9%增大到32.2%的同时,烟道出口氨气泄漏量从5μmol/mol增加到46μmol/mol。在氨氮比为1.5时有最理想的脱硝效果,脱硝率为28.3%,烟道出口氨气泄漏量为11.2μmol/mol。

Study on influencing factors of selective non-catalytic reduction denitration(SNCR)operation in large coal-fired power plants,using the CFD to simulate the denitration process with urea as the reducing agent sprayed into the furnace.The calculation results show that when the unit is running at full load,the height of the top of the furnace to meet the SCNR denitration temperature window is more than 57 m,therefore,three,five,and six zone urea solution spray guns are used.With the increase of ammonia-nitrogen ratio,the denitration rate increased from 25.9%to 32.2%,The amount of ammonia leakage at the flue outlet increased from 5μmol/mol to 46μmol/mol.The best denitration effect when the ammonia-nitrogen ratio is 1.0~1.5,The denitration rate was 28.3%,and the amount of ammonia leakage at the flue outlet was 11.2μmol/mol.