为满足规模化太阳能热发电中对传热蓄热的要求,针对储能材料开展探究。以熔融盐热物性及经济性作为筛选条件,选定来源广泛、价格低廉、工作温度范围宽、黏度低、相变潜热大的NaCl、MgCl2和CaCl2三元熔盐体系开展深入研究。应用修正的准化学溶液模型,在子二元系基础上推导计算三元混合熔盐NaCl-MgCl2-CaCl2相图。结果表明,该熔盐混合物共晶点温度为412.45 ℃,NaCl、MgCl2和CaCl2的摩尔分数分别为50.99%、22.78%和26.23%,与已有文献数据相比,误差在3%以内,验证了方法的准确性,为构建熔盐氯化物相图数据库奠定了部分基础。
Abstract
Energy storage materials have been widely studied and used to meet heat transfer requirements and storage in large-scale solar thermal power generation. Taking the thermal physical properties and economy of molten salt as screening conditions, ternary molten salt systems of NaCl, MgCl2, and CaCl2 with wide sources, low price, wide operating temperature range, low viscosity, and large latent heat of phase transition were selected for in-depth study. Based on the sub-binary system., the modified quasi-chemical solution model was used to calculate the phase diagram of ternary mixed molten salt NaCl-MgCl2-CaCl2. The calculated results show that the eutectic point temperature of the molten salt mixture is 412.45 ℃, and the molar fractions of NaCl, MgCl2, and CaCl2 is 50.99%, 22.78%, and 26.23%, respectively. Compared with the existing literature data, the error is less than 3%, which verifies the accuracy of the method. It lays a partial foundation for the construction of a phase diagram database of molten salt chloride.
关键词
太阳能热发电 /
熔盐相平衡 /
三元相图 /
修正的准化学溶液模型
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