某新型蒸汽脉冲式声频清灰器清灰机理及经济性分析

摘要

燃煤锅炉受热面大都存在积灰和结渣现象,使用高灰分和高硫分煤的锅炉积灰问题更为严重.基于对现有清灰器的优缺点分析,本文推出一种新型蒸汽脉冲式声频清灰器.对该清灰器三维流道建模,结合声波清灰原理详细分析清灰过程中流体总压降随开度变化关系以及流场中压力和速度的变化趋势;对比某电厂安装该清灰器运行前后的部分关键数据,计算该清灰器带来的经济效益与环保效益.结果表明:清灰器开度变化时,流体域每一点均会产生压力和速度脉动,将流体的机械能转化为脉冲波振荡,从而实现清灰目的;该清灰器投运某锅炉后,排烟温度平均降低16.35℃,且未发生低温腐蚀,年节煤量与节汽量分别为1650 t和21192 t,CO2与SO2的年减排量为726 t和33 t,此外,每年还可减少约25 t烟尘和429 t灰渣排放,年发电耗煤节约160万元以上,年获益98万元.%The fouling and slagging phenomena usually occur on heating surface of coal-fired boilers, and the problem of fouling becomes more serious when the boiling fires high ash and high sulfur content coal. To solve this problem, the advantages and disadvantages of the existing cleaning devices were analyzed. On this basis, a new type of steam pulsed acoustic dust cleaning device was developed in this paper. The three-dimensional flow path of the cleaning device was built. Combined with the principle of acoustic cleaning, the relationship between the total pressure drop of the fluid and the opening degree as well as the change trend of the pressure and velocity in the flow field were analyzed in detail. Finally, part of the key data of the power plant before and after the new cleaning device was put into service was compared, and the economic and environmental benefits were calculated. The results show that, the pressure and velocity pulsation are generated at each point in the fluid domain when the opening degree of the settler is changed. During this process, the mechanical energy of the fluid is converted into pulsed wave oscillation to realize cleaning. After the cleaning device is installed on the boiler, the exhaust temperature decreases by an average of 16.35℃ and no low temperature corrosion is observed. The annual coal conservation and steam conversation are 1650 t and 21192 t, The annual emission reduction of CO2 and SO2 are 726 t and 33 t respectively. In addition, it can also reduce the soot and slag emission by 25 t and 429 t each year. The money saved due to coal consumption is more than 1.6 million yuan per year and the annual economic benefit is 980000 yuan.