钾明矾/膨胀石墨定形复合相变材料储热性能研究  

Study on Heat Storage Performance of Potassium Alum/Expanded Graphite Form-stable Composite Phase Change Material

作　　者：霍英杰 闫霆 王凯 潘卫国 HUO Yingjie;YAN Ting;WANG Kai;PAN Weiguo(Shanghai University of Electric Power,Shanghai 200090,China;East China Electric Power Design Institute Co.,Ltd.,Shanghai 200063,China)

机构地区：[1]上海电力大学,上海200090 [2]华东电力设计院有限公司,上海200063

出　　处：《上海电力大学学报》2022年第5期450-456,465,共8页Journal of Shanghai University of Electric Power

基　　金：上海市科学技术委员会科技攻关项目(21DZ1207203)。

摘　　要：选用十二水硫酸铝钾(钾明矾)为相变材料,采用化学改性后的膨胀石墨为支撑材料,利用“熔融共混凝固定形”法制备了定型复合相变材料。通过扫描电子显微镜(SEM)、差示扫描量热分析仪(DSC)和热重分析仪(TGA)分别研究了样品的微观形貌、相变焓及其熔化过程。改性膨胀石墨质量分数为20%的样品能够均匀吸附大量相变材料。DSC分析结果表明,其熔点和熔融焓分别为84.39℃和473.52 kJ/kg。经过50次的充放热循环测试,改性膨胀石墨质量分数为20%的样品的熔融焓仅下降7.48%。改性膨胀石墨与钾明矾具有良好的相容性。充放热测试表明,该复合相变材料具有良好的循环稳定性,是一种性能优良的相变热储存材料,在建筑物节能领域和太阳能热利用中具有广阔的应用前景。Aluminum potassium sulfate dodecahydrate(potassium alum)was selected as phase change material,chemically modified expanded graphite was used as supporting material,and the composite phase change material was prepared by the“melt blending-solidification and form-stability”method.The microstructure,melting enthalpy,and melting process of the sample were characterized by SEM,DSC,and TGA,respectively.The sample with a mass fraction of 20%modified expanded graphite can uniformly adsorb a large number of phase change materials.DSC analysis results show that its melting point and enthalpy of are 84.39℃and 473.52 kJ/kg,respectively.After 50 charging-discharging cycles,the phase transition enthalpy of the sample with a mass fraction of 20%modified expanded graphite only decreased by 7.48%.The modified expanded graphite has good compatibility with potassium aluminum sulfate dodecahydrate.The charging-discharging cycle tests indicate that this composite phase change material has good cycle stability and is an excellent phase change heat storage material.It has broad application prospects in the field of building energy saving and solar thermal utilization.

关 键 词：十二水硫酸铝钾 改性膨胀石墨 相变材料 循环稳定性 储热性能 

分 类 号：TK02[动力工程及工程热物理] TK115