吸收式湿热空气余热回收系统的模拟分析

Analysis of the Simulation of an Absorption Type Humidified Hot Air Waste Heat Recovery System

通过对典型烘干热力过程的分析,提出了基于溶液除湿和吸收式热泵原理的湿热空气余热回收系统,该系统可以在典型烘干机排气余热和太阳能热水的共同驱动下产生120℃左右饱和蒸汽,用于部分替代烘干热源,实现节能。通过建立热力学模型,对系统方案进行了验证,并讨论了蒸发器温度、发生器温度对系统各性能指标的影响。计算表明:选用溴化锂水溶液作为吸收剂,在蒸发温度80℃,发生器工作温度为63℃的条件下,烘干机可节能33.45%,系统COP为0.43,其中驱动热量中有79%来自湿热废气,吸收液的总喷淋量为排气质量的6.33倍。

Through analyzing the typical drying thermodynamic process,the authors put forward a scheme for a humidified hot air waste heat recovery system based on the principles for dehumidification by solutions and absorption type heat pumps. The system in question produced saturated steam at a temperature of around 120℃ when it was jointly driven by the waste heat from the exhaust gases of a typical dryer and solar energy-produced hot water,partially substituting the drying heat source to realize the energy saving. Through establishing a thermodynamic model,the scheme for the system was verified with the influence of the evaporator temperature and generator temperature on various performance indexes of the system being discussed. The calculation results show that with the lithium bromide solution being chosen as an absorbent,under the condition of the evaporation temperature being 80 ℃ and the working temperature of the generator being 63 ℃,the energy saving of the dryer at an efficiency of 33. 45% can be realized with the COP( coefficient of performance) of the system being 0. 43,among which 79% of the heat quantity serving as the driving force comes from the humidified hot exhaust gas and the total sprinkling quantity of the absorption solution is 6. 33 times of the mass of the exhaust gas.