Comparative analysis of thermophysical properties of mixed nitrates

doi:10.12028/j.issn.2095-4239.2019.0081

Abstract

Abstract: Molten salt as heat transfer and storage medium has been widely used in solar power generation. Nitrate has been successfully applied in commercial power plants due to its low melting point, low cost and low corrosiveness. In this paper, different characterization techniques including differential scanning calorimetry, thermogravimetric method, DIN method, laser flash method, Archimedes principle and rotation method will be used to measure and compare the melting point, decomposition temperature, specific heat, thermal conductivity, density and viscosity of solar salt (60% NaNO₃+40% KNO₃), Hitec (7% NaNO₃+53% KNO₃+40% NaNO₂), Hitec XL[7% NaNO₃+45% KNO₃+48% Ca(NO₃)₂] and quaternary mixed nitrates(16.67% Ca(NO₃)₂·4H₂O+44.17% KNO₃+5.83% NaNO₃+33.33% NaNO₂) independently developed by our group. The advantages and disadvantages of thermal properties of four kinds of mixed nitrates were analyzed, which provided basic data for engineering application. The results show that among the four kinds of mixed nitrates, the quaternary salt has the lowest melting point, the highest decomposition temperature, the highest average specific heat and thermal conductivity, while the Hitec XL has the highest density and Solar salt has the the lowest viscosity.

Key words: heat storage medium, nitrate, thermal properties

CLC Number:

TM123

HAN Yan, WU Yuting, MA Chongfang. Comparative analysis of thermophysical properties of mixed nitrates[J]. Energy Storage Science and Technology, 2019, 8(6): 1224-1229.

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