针对SCR脱硝氨逃逸造成的空气预热器堵塞问题，构建了可反映蓄热板表面飞灰碰撞、粘附与脱离特性的硫酸氢铵（ABS）粘结性积灰计算模型，并对比分析了锅炉在50%~100%最大连续蒸发量工况（BMCR）之间的6种负荷下蓄热板间烟气流速分布及ABS粘结性和松散性积灰的积灰强度、积灰概率等积灰特征量，同时对30% BMCR负荷下蓄热板表面积灰情况进行了预测。结果表明：各负荷下ABS粘结性积灰强度均为松散性积灰强度的4.8倍以上；负荷每增加10%，ABS粘结性积灰与松散性积灰强度分别增加约9.90和2.15 μg/mm2，ABS粘结性积灰强度增加量较大；ABS粘结性积灰区域随负荷增大逐渐减小，当负荷由50%增大到100%时，积灰上限向冷端移动0.07 m；ABS粘结性积灰概率受负荷影响较小，各负荷下均为0.9，而松散性积灰概率为0.2~0.4，且随着飞灰粒径增大而降低。

Aiming at the problem of air preheater blockage caused by the escape of SCR denitrification ammonia,a calculation model of ammonium bisulfate (ABS) cohesive ash accumulation that can reflect the collision,adhesion and detachment characteristics of fly ash on the surface of the regenerative plate was constructed.At the boiler maximum continuous rating (BMCR) of 50% to 100%,the flue gas flow rate distribution between the regenerative plates and the ash accumulation characteristic quantity under six boiler loads,such as ash accumulation intensity and probability of ash accumulation of ABS adhesion and looseness,were analyzed contrastively.Meanwhile,the ash accumulation situation on the surface of the regenerative plate at BMCR of 30% was predicted.The results show that the ABS cohesive ash accumulation intensity is 4.8 times or more than the loose ash accumulation intensity under each load; For every 10% increase in load,the intensities of ABS cohesive ash accumulation and loose ash accumulation are increased by about 9.90 μg/mm2 and 2.15 μg/mm2 respectively,and the increase of ABS cohesive ash accumulation intensity is greater; The cohesive ash accumulation area of ABS gradually decreases with the increase of load.When the load increases from 50% to 100%,the upper limit of cohesive ash accumulation moves 0.07 m towards the cold end; The probability of cohesive ash accumulation of ABS is less affected by the load,which remains 0.9 under each load,while the probability of loose ash accumulation is 0.2 to 0.4,which decreases with the increase of fly ash particle size.

TK224.9