适于温室应用的六水氯化钙的性能研究

Study on Properties of Calcium Chloride Hexahydrate Suitable for Greenhouse Application

六水氯化钙潜热值较高,但过冷严重导致无法充分释放热量。为了解决其过冷现象,以便将其应用于温室,自制了六水氯化钙晶体,加入不同种类、质量的成核剂和增稠剂,通过熔解冷却实验和差示扫描量热法进行热性能测试和分析。实验结果表明:硼砂、氧化铝、九水硅酸钠为六水氯化钙的优良成核剂,CMC为增稠剂;分别向六水氯化钙中加入1%硼砂+1%CMC,1%氧化铝+4%CMC,1%九水硅酸钠+2%CMC可以有效解决六水氯化钙多循环过冷度增大和相变时间缩短现象,200次循环性能稳定;加入适当比例成核剂和增稠剂的六水氯化钙具有较高潜热值和合适相变温度。

The latent heat which could not be released because of the undercooling of calcium chloride hexahydrate was high, so this experiment aimed at resolving the phenomenon in order to apply it to the greenhouse. The self-made calcium chloride hexahydrate added with different types and weights of the nucleating/thickening agents was tested and analyzed by solidification experiments and differential scanning calorimetry （ DSC ）. The experiment showed that the three kinds of nucleating agents and CMC were excellent, so the problem of undercooling and phase separation was solved by adding 1% borax ＋1% CMC or 1% aluminum ＋4% CMC or 1% sodiumsilicate ＋2% CMC to calcium chloride hexahydrate. Calcium chloride hexahydrate has high latent heat and proper transformation temperature by adding different proportions of nucleating agents and thickening agents.