锅炉排烟余热深度回收利用节能改造工程实测分析

Measurement and analysis of boiler flue gas heat deep recovery in an energy efficiency reformation project

应用防腐型烟气冷凝热回收装置对北京某供暖锅炉房进行了排烟余热深度回收利用节能改造,将烟气作为吸收式热泵的低温热源用于供热。工程跟踪实测表明,采用烟气冷凝热回收装置可将锅炉排烟温度从84～114℃降到27～43℃,提高燃气利用效率(单项节能率)7.2%～13.6%;回收的烟气余热中水蒸气凝结潜热占68%～84%;排烟温度平均每降低10℃,锅炉系统总热效率提高约1.0%～2.3%;单位容量(1t/h)锅炉每天产生0.8～3.0t/d的烟气冷凝水,可回收利用;烟气冷凝水对烟气有显著的净化作用。因此,锅炉低温烟气余热深度利用有较大的节能、节水、减排潜力。

Taking the flue gas as low temperature heat source of absorption heat pumps for heating, performs the energy efficiency reformation using the anti-corrosion type flue gas condensing heat recovery unit in a heating boiler room in Beijing. The field measurement results show that the exhaust gas temperature can be reduced from 84 - 114 ℃ to 27 - 43 ℃ with the efficiency of gas utilization （energy saving） increasing by 7%- 14% ; the latent heat of condensation of water vapor accounts for 68%- 84% of the recovered total heat; the energy saving rate is 1.4% -3.2% for each 10 ℃ dropping of smoke temperature; flue gas condensate water of 0.8 - 3.0 tons for recycling use is produced for 1 t/h of boiler capacity per day; moreover, the condensate water has a significant effect of flue gas purification. Concludes that, there is a huge potential for energy saving, water saving and emission reduction by reusing the waste heat of the low temperature flue gas.