高温碳酸熔盐的制备及传热蓄热性质  

Preparation and heat transfer and thermal storage property of high-temperature carbonate molten salt

作　　者：廖敏[1] 丁静[2] 魏小兰[3] 杨晓西[1,4] 杨建平[1] 

机构地区：[1]华南理工大学传热强化与过程节能教育部重点实验室,广东广州510640 [2]中山大学工学院 [3]华南理工大学化学与化工学院 [4]东莞理工学院

出　　处：《无机盐工业》2008年第10期15-17,共3页Inorganic Chemicals Industry

基　　金：国家高技术研究发展计划项目(2004AA516010);广东重点科技项目(2004B40401006)

摘　　要：为满足太阳能高温传热、蓄热的要求,根据碳酸盐的相图数据,利用静态熔融的方法制备了碳酸钠-碳酸钾新型熔盐,并对熔盐添加氯化钠、氯化钾、碳酸锂等高熔点物质进行改性,采用差式扫描量热法(DSC)、重量法、电位滴定法和热循环法对混合熔盐的熔点、相变潜热、离子变化、热稳定性等热力学性质进行了表征。实验结果表明,碳酸锂改性后的碳酸熔盐熔点和相变潜热数据较氯化钠、氯化钾改性的优越,但价格较贵,不适合作为太阳能高温传热介质;价格较低的氯化钠改性后的碳酸熔盐具有熔点比二元碳酸熔盐低133℃、相变潜热增加为二元碳酸熔盐的1.9倍和在850℃以下热稳定性好的特点,是一种比较理想的高温热载体。To meet the requirement of high temperature of solar heat transfer and thermal storage, a new type of Na2CO3 - K2CO3 molten salt was prepared by static fusion method according to the phase diagram data of carbonate. It was modified by high melting point additives, such as NaCl, KCl, and Li2CO3. Thermal properities such as the melting point, phase transition latent heat, ion change, and thermal stability of the mixed molten salts were characterized by thermal gravimetric and differential thermal analysis, gravimetric method, potentiometric titration method gand thermal circulation method. Experimental results showed that the modified carbonate molten salt with Li2CO3 had better melting point and phase transition latent heat data than that with NaCl and KCl, but the cost was high. Therefore, it was not suitable to be the solar heat transfer medium. The carbonate molten salt modified by low - cost NaCl is a perfect high - temperature carrier, whose melting point was 133 ℃ lower than that of binary carbonate salt,phase transition latent heat was 1.9 times as large as binary carbonate salt and thermal stability was good under the temperature of 850 ℃.

关 键 词：太阳能 传热蓄热 碳酸熔盐 

分 类 号：TQ127.13[化学工程—无机化工]