新型低品位热驱动吸收式高效空调系统

New type of energy efficient absorption air conditioning system driven by low-grade heat

针对常规热驱动制冷除湿技术在热源温度低于80℃时能效较低,甚至不能正常工作的问题,通过溶液除湿系统和吸收式制冷系统的有机耦合,提出了一种由低品位热驱动的高效空调系统.通过对比本系统和常规系统内部的热力过程,指出了本系统能效较高的主要原因在于节省了再生空气温升造成的热损失,以及通过热湿独立处理技术提升了蒸发温度.对比结果表明,本系统性能的主要影响因素及变化规律为,热源温度越高,冷却水温度越低,蒸发温度越高,除湿器出口空气含湿量越高,系统能效越高;除湿侧和制冷侧能效不同时,显热负荷占比也对系统性能有影响.当热源温度为75℃、除湿器出口空气含湿量为9.5 g/kg、蒸发温度为14℃时,本系统性能系数可达0.87,比常规系统高出40%.

To solve the problem that conventional heat driven refrigeration and dehumidification technologies have relatively low energy efficiency or even not work normally when the heat source temperature is lower than 80℃,an energy efficient air conditioning system driven by low-grade heat was proposed through the integration of the liquid desiccant dehumidification system and the absorption refrigeration system.By comparing the internal thermodynamic process of the system with that of the conventional system,it was pointed out that the main reason for the high energy efficiency of the system was to save the heat loss caused by the temperature rise of the regeneration air,and to increase the evaporation temperature through the independent heat and humidity treatment technology.The results show that the main influencing factors and changing rules of the system performance are as follows:the higher the heat source temperature,the lower the cooling water temperature,the higher the evaporation temperature,the higher the air humidity ratio at the dehumidifier outlet,and the higher the system energy efficiency.When the energy efficiency of the dehumidification side and the refrigeration side is different,the proportion of sensible heat load also affects the system performance.The coefficient of the system performance can reach 0.87,when the heat source temperature is 75℃,the humidity ratio of the outlet air of dehumidifier is 9.5 g/kg,and the evaporation temperature is 14℃,which is 40%higher than that of the conventional systems.