Phase Diagram Predictive Model for a Ternary Mixture of Calcium, Sodium, and Potassium Nitrate

Abstract

The development of low-melting mixtures is crucial for the diffusion of sustainable and green alternative energy sources, namely, CSP. Ternary mixtures containing sodium, potassium, and calcium are extremely promising as thermal fluids due to their good thermophysical properties, low toxicity and cost. Most literature studies on ternary mQ4ixtures refer to a particular commercial composition and there are few data regarding ternary phase diagrams. Thus, for improving the current understanding on this topic, further theoretical and experimental investigation on ternary mixtures is of utmost interest. An experimental campaign was conducted to study the binary subsystems of the ternary mixtures and develop a regular solution model for simulating the ternary phase diagram. To validate the model, several data were determined using an innovative experimental rheometric method. The results showed that a ternary contribution in the regular solution model is necessary and an empirical expression for this ternary parameter was proposed and validated.

Development of NaCl–MgCl2–CaCl2 Ternary Salt for High-Temperature Thermal Energy Storage Using Machine Learning

“…In the third-generation CSP roadmap proposed by the U.S. Department of Energy, the existing steam Rankine cycle system for power generation is expected to be replaced by a supercritical CO 2 Brayton cycle system . This new technology requires a working temperature range of 520–720 °C for the heat transfer and storage medium, while the commonly used molten salts internationally, such as Solar Salt and Hitec Salt, have lower working temperatures that cannot meet the requirements. , Chloride salts possess excellent thermal stability and are considered as a promising heat storage medium for future CSP power plants. − In order to provide more comprehensive and accurate thermophysical data for the next-generation CSP, this study employs deep potential molecular dynamics (DPMD) simulations to investigate the local structure and thermal properties of the NaCl–MgCl 2 –CaCl 2 eutectic chloride salt.…”

Phase Equilibria in the KNO3–Ca(NO3)2–H2O System at 25°C

“…The applications of heat storage materials diversify from storage systems and transportation of materials [8,14] through heating and cooling of buildings [15][16][17][18] to the automotive industry [19,20], the textile industry, and medicine [7]. In recent years, high-temperature multicomponent mixtures have been developed for solar energy storage in commercial power plants; they have good thermophysical properties, lower crystallization temperatures, low toxicity, and low costs compared to their analogues [21][22][23].…”