热电联产电厂烟气余热回收系统改造实践与分析

对热电联产电厂的烟气余热回收进行了改造实践和分析，提出了2级式氟塑钢换热器改造方案，分析了新型烟气余热回收系统的运行特性，评估了烟气余热回收系统的经济效益。实际运行数据表明，冷凝器的传热系数为174.1 W/（m2·K），是低温省煤器传热系数的约3.7倍。低温省煤器和冷凝器的换热量分别约占余热回收系统热回收量的57%和43%。通过回收系统，实现了年节煤量达9 800 t，年节水量达67 900 t。烟气余热回收系统的投资成本可在1.64 a内收回，随后可实现年净收益540.9万元。

Practice and Analysis of Flue Gas Waste Heat Recovery System in Co-generation Plant

The renovation practice and analysis of the flue gas waste heat recovery were performed for the co-generation plant.A two-stage fluoroplastic steel heat exchanger scheme was proposed, the operation characteristics of the new flue gas waste heat recovery system were analyzed, and its economic benefits were evaluated.Based on the operation data, the heat transfer coefficient of the condenser is 174.1 W/(m2·K), which is 3.7 times of the low temperature economizer.The low-temperature economizer and the condenser account for 57% and 43% of the heat recovery of the waste heat recovery system respectively.Through the flue gas waste heat recovery system, the annual coal saving is 9 800 tons, and the annual water saving is 67 900 tons.The investment cost of the flue gas waste heat recovery system can be recovered within 1.64 years, and then the net present value is up to 5.409 million yuan.