【作者】 张晴；

【导师】 刘文斌； 管延文；

【作者基本信息】 华中科技大学 ， 建筑与土木工程， 2014， 硕士

【摘要】 常规壁挂炉排烟温度在120℃以上，排烟中含有大量的烟气显热和水蒸气潜热，若能加以回收，可显著提高壁挂炉热效率。近年来，壁挂炉冷凝技术以其节能环保的特性受到越来越多的关注，是壁挂炉采暖行业发展的新方向。本文结合壁挂炉排烟及热泵运行的特点，提出了热泵回收烟气冷凝热系统，与常规换热器回收烟气余热系统比较，并分析了两种系统的节能与经济性。本文以壁挂炉采暖为研究对象，首先对余热回收方式进行综述，分析了各类方式在壁挂炉采暖中实现的弊端。针对热泵回收烟气冷凝热系统，论述了该系统的组织型式，包括压缩式热泵及吸收式热泵。其次，分析了天然气燃烧特性及排烟热损失的计算方法，以此为基础得到排烟温度及空气相对湿度对热泵回收烟气冷凝热及常规换热器回收烟气余热系统的影响曲线。排烟温度越低，系统越节能；空气湿度越高，连接热泵系统热效率越高。对比两种系统，热泵回收烟气冷凝热系统更节能。最后，在节能性分析的基础上，从投资与收益的角度分析不同排烟温度下的两种系统的静态投资回收期及寿命周期内的累计节省费用。从投资回收期的角度，常规换热器回收烟气余热系统的最佳排烟温度为100℃，此时投资回收期为0.71年；热泵回收烟气冷凝热系统的最佳排烟温度为35℃，此时投资回收期为1.82年。从累计节省费用的角度，两种系统都是排烟温度越低，累计节省费用越高，但增加幅度变缓。更多还原

【Abstract】 The exit flue gas temperature of conventional wall mounted boiler is above120℃.Great amount of sensible heat and latent heat of water vapor is contained in the flue gas,can be recovered by some methods, which will lead to a significant improvement of theboiler thermal efficiency. For the sake of its energy saving and environmental protection,the condensation technology of wall mounted boiler is gaining more and more attention inrecent years, which becomes a new development direction of wall mounted boiler heatingindustry. In this dissertation, according to the characteristics of wall mounted boilerexhaust and heat pump operation, a condensing heat recovery system by heat pump isproposed, and is compared with the waste heat of flue gas recovery system byconventional heat exchanger. Also, the energy saving and economy of the two systems isanalyzed.This thesis takes wall mounted boiler heating as the object. First of all, the methodsof flue gas heat recovering have been reviewed, and the shortcomings about the wallmounted boiler heating are analyzed. For the condensing heat of flue gas recovery systemby heat pump, its organization forms are discussed, including the compression heat pumpand the absorption heat pump.Secondly, the characteristics of natural gas combustion and the calculation methodsof the exit heat loss are analyzed. Therefore, curves how the exit gas temperature and airrelative humidity affect the condensing heat of flue gas recovery system by heat pumpsystem and waste heat of flue gas recovery system by conventional heat exchanger havebeen obtained. Lower the exit gas temperature, higher the system efficiency. And higherthe air relative humidity, higher the efficiency of the combining heat pump system.Compared to the two systems, condensing heat of flue gas recovery system by heat pumpis more energy efficient.Finally, from the perspective of investment and income, the static payback period andcumulative life cycle cost savings of the two systems under different exhaust temperaturesis analyzed on the basis of the energy-saving analysis. From the point view of the paybackperiod, the optimal exhaust gas temperature is100℃for the waste heat of flue gas recovery system by conventional heat exchanger, whose payback period is0.71years.And the optimal exhaust gas temperature is35℃for the condensing heat of flue gasrecovery system by heat pump, whose payback period is1.82years. In the view ofcumulative cost savings, for both systems, lower the exit gas temperature, higher thecumulative cost savings, but the rate of increase slows.更多还原