440t/h锅炉管式空预器堵灰原因分析与治理

Analysis and Treatment of Ash Plugging of the Shell-and-Tube Air Preheater of the 440 t / h Boiler

对某电厂2台440 t/h锅炉管式空气预热器堵灰问题进行了计算和分析,指出了导致空气预热器堵灰的主要原因为烟气结露、烟气流速低与分布不均等.根据锅炉设计和运行特点,制定了加装围板提高空气预热器末端管壁温度、封堵部分换热管以及增加导流板等可行的技术改造方案,改造后的机组实现了长周期的稳定运行.

The ash plugging and its reasons of the shell-and-tube air preheaters of two 440 t/h boilers are presented and analyzed. The reasons include the condensation, low velocity and uneven distribution of flue gas in the preheaters. According to the boiler design and operation characters, the renovation measures are presented, which are increasing the temperatures at the end of heat exchange tubes, plugging some heat exchange tubes and installing baffles. Finally, satisfactory results are obtained after renovation.