活性氧化铝基质新型复合吸附剂的制备和储热性能

Preparation and thermal storage performance of novel composite sorbent with activated alumina matrix

研制了一种以活性氧化铝为基质、CaCl2为吸湿盐的新型复合吸附剂,可用于以水为吸附质的热化学吸附储热系统,并对其内部结构、吸附性能和储热性能进行了研究。利用恒温恒湿箱确定出现溶液泄漏现象的最大含盐量,并对30℃和多种相对湿度工况下的动态和平衡吸附特性进行测量,研究了含盐量和相对湿度对吸附剂的吸附特性的影响,结果表明含盐量和相对湿度越大,复合吸附剂的吸水能力越强。利用全自动比表面积与孔隙度分析仪测量材料的比表面积和孔体积,利用同步热分析仪测试了复合吸附剂的储热密度,其中含盐量最高的复合吸附剂的储热密度最高,质量和体积储热密度分别达到0.51 kW·h/kg和610.2 kW·h/m^3,具有良好的储热性能。

A new type of composite adsorbent based on activated alumina(AA)and CaCl2 as a hygroscopic salt was developed.It can be used in thermochemical adsorption heat storage systems with water as the adsorbent,and its internal structure,adsorption performance and heat storage performance were studied.Samples with different salt contents were fabricated to store low-temperature thermal heat by impregnation methods.Morphologies records,sorption kinetics and thermal energy storage performance of AA/CaCl2 composite sorbent were investigated.The maximum salt content of the solution leakage phenomenon was determined.Sorption kinetics and equilibrium sorption capacity under conditions of 30℃and multi relative humidity were studied by utilizing constant temperature and humidity chamber.Influence of salt content and relative humidity on the sorption performance of AA/CaCl2 composite sorbent was studied.Results showed sorption capacity of AA/CaCl2 composite sorbent increased with increasing salt content and relative humidity.The specific surface area and pore volume were measured by automatic specific surface area and porosity analyzer.Energy storage density was measured by simultaneous thermal analyzer.The sample with highest salt content had the best energy storage performance with 0.51 kW·h/kg mass energy storage density and 610.2 kW·h/m^3 volumetric energy storage density.As a consequence,AA/CaCl2 composite sorbent is promising sorbent in field of chemisorption thermal energy storage.