氯化锰/氨热化学吸附储热的特性

Performance of thermochemical sorption heat storage using manganese chloride/ammonia

热化学吸附储热具有储热损失小、储热密度高、可实现冷热复合储存等优点,近年来得到了广泛的关注。本文以MnCl_(2)/NH_(3)作为吸附储热工质对,基于热化学吸附技术构建了热化学吸附储热实验平台,对MnCl_(2)/NH_(3)热化学吸附系统的储热性能进行了理论分析和实验研究。结果表明:在解吸充热温度、吸附放热温度、冷凝/蒸发温度分别为162℃、45℃和25℃的运行条件下,试验获得的吸附储热密度最大,其值为1296.36kJ/kg MnCl或1101.90kJ/kg固化复合吸附剂。当放热温度从45℃增大到85℃时,热化学吸附储热系统的吸附储热效率从38.98%降低至24.08%。由于传热传质、化学反应动力学等因素的影响,相同运行工况下吸附储热系统实际所获得的储热性能要低于理论值。

Thermochemical sorption heat storage has attracted extensive attention in recent years because of its advantages such as low heat storage loss, high heat storage density and cold and hot composite storage. An experimental test system of thermochemical sorption heat storage was established based on the thermochemical sorption technology. For direct thermal energy storage and release mode of thermochemical sorption heat storage, theoretical analysis and experimental research were conducted by employing the MnCl_(2)/NH_(3) as the working pair. The results showed that the highest thermochemical sorption heat storage density was 1296.36kJ/kg MnCl_(2) or 1101.90kJ/kg consolidated composite sorbent under the charging temperature of 162℃, discharging temperature of 45℃ and condensation/evaporation of 25℃. The thermochemical sorption heat storage efficiency decreased from 38.98% to 24.08% when the discharging temperature increased from 45℃ to 85℃. Due to the influence of heat and mass transfer, chemical reaction kinetics and other factors, the actual heat storage performance of the sorption heat storage system under the same operating conditions was lower than the theoretical value. Thermochemical sorption heat storage was a very promising way for thermal energy storage, which could be used in the efficient recovery and utilization of medium and low temperature thermal energy, such as solar energy and industrial surplus/waste heat. This work could provide the strong technical support and had the important guiding significance for practical industrial application.