基于烟气-空气全热交换的余热回收系统实验研究  

Experimental study on gas-air total heat exchange based waste heat recovery system

作　　者：魏茂林 张世钢 付林[2] 赵玺灵[2] 王静贻 Wei Maolin, Fu Lin ,Zhao Xiling, Zhang Shigang(Department of Energy- Planning ＆ Design;Tsinghua Planning ＆ Design Institut)

机构地区：[1]北京清华同衡规划设计研究院 [2]清华大学

出　　处：《区域供热》2018年第4期6-13,18,共9页District Heating

基　　金：国家自然科学基金青年基金(51706115)

摘　　要：回收燃气烟气中的热量能够显著提高燃气的利用效率。本文提出了一套新型的烟气余热回收系统,该系统通过全热交换,将烟气中的热量传递给锅炉的助燃空气,同时提高空气的温度和湿度,从而提高了锅炉排烟的露点,高湿烟气通过与热网回水的换热,实现余热回收。本文针对一台1.4MW蒸汽锅炉进行了实验研究,结果表明,在热网回水温度为50℃的情况下,锅炉助燃空气被加热到50℃,锅炉排烟露点提高到60℃,最终排烟温度由80℃降低至30℃,回收热量约127k W。同时,实验结果还表明新系统能够降低锅炉污染物排放水平,NOx含量由33ppm降低至24.6ppm。该系统能够达到节能,减排的双重效果。Recycling waste heat from the boiler flue gas can improve the boiler efficiency effectively. A gas-air total heat exchange based waste heat recovery system is built in this paper. The boiler oxidizing air is heated and humidified by the flue gas through a total heat exchange process. Thus the dew point of the boiler outlet flue gas is improved. Then the waste heat can be recovered by the heat pipe return water through a gas-water heat exchanger. The system was built with a 1.4MW gas boiler. According to the experiment results, the exhaust flue gas temperature reduced from 80℃ to 30℃. The recycled heat amount reached over 127kw. Besides of energy saving, the vapor-pump system also can reduce the pollutant emission concentration. The exhaust NOx decreased from 33ppm to 24.6ppm, the reduction was about 25.5%. The system achieves energy saving and emission reduction simultaneously.

关 键 词：烟气 余热回收 空气加湿 减排 燃气锅炉 热交换 

分 类 号：TK223[动力工程及工程热物理—动力机械及工程] X706[环境科学与工程—环境工程]