热泵型烟气冷凝余热回收系统实验研究

Experimental Study on Heat Pump Type Flue Gas Condensation Waste Heat Recovery System

为充分回收燃气锅炉排放烟气中的冷凝余热,本文提出了1种热泵型烟气冷凝余热回收方式.该方式分级回收烟气高温显热与冷凝潜热,搭建了热泵型烟气冷凝余热回收实验台,研究了热网回水温度、热网回水流量对该系统的余热回收效率、余热利用效率、排烟温度、供热水温度与热泵机组制热性能系数的影响.该余热回收系统可实现向热网直接供热与向热网回水预热两种运行模式.在预热运行模式下,当热网回水温度为40.0℃,热网回水流量为11.0 L/min时,热泵型烟气余热回收系统的烟气余热回收效率是11.9%,其余热利用效率可到15.9%,系统的排烟温度可降至19.8℃,热泵机组的制热性能系数为3.3.该热泵型烟气冷凝余热回收方式节能效果显著,具有较好的推广应用前景.

In order to fully recover the waste heat of condensation in the flue gas discharged from the gas-fired boiler,this paper proposed a heat pump type waste gas heat recovery method of condensation. In this way,the high-temperature sensible heat of the flue gas and the latent heat of condensation were recovered in stages. A heat pump-type flue gas condensing waste heat recovery test bench was built to study the influence of return heat temperature and the return flow rate of the heat network on the system’s waste heat recovery efficiency,waste heat utilization efficiency,exhaust temperature,hot water supply temperature and heating performance coefficient of the heat pump unit. This waste heat recovery system can realize two operation modes: direct heating to the heating network and preheating to the heating network. In the preheating operation mode, when the return water temperature of the heating network is 40. 0 ℃ and the return flow rate of the heating network is 11. 0 L/min,the heat recovery efficiency of the flue gas waste heat recovery system of the heat pump flue gas waste heat recovery system is 11. 9%,and the waste heat utilization efficiency can reach 15. 9%,the exhaust temperature of the system can be reduced to 19. 8 ℃,and the heating performance coefficient of the heat pump unit stands at 3. 3. This heat pump type flue gas condensation waste heat recovery method has significant energy-saving effects,and good prospects for popularization and application.