Experimental study on seepage flow characteristics of leaked molten salt in foundation fillers in concentrating solar power plants

Abstract

The leakage of molten salt storage tanks in concentrating solar power plants has attracted much attention. This paper focused on seepage and migration characteristics of molten salt in the thermal‐steady foundation fillers with different configurations after leakage occurs through a self‐built experimental system modeling the actual leaking process. The results show that the thermal insulation of light expanded clay aggregate (LECA) as foundation fillers is better than that of sand and gravel. When the operating temperature is 565°C, the average temperatures of each layer of LECA, sand, and gravel are 131.73°C, 141.91°C, and 149.27°C, respectively. And the seepage depths in light expanded clay aggregate, sand, and gravel are 482 mm, 223 mm, and 270 mm, respectively. It is found that the seepage depth of molten salt distinctly increases with higher operating temperature in all kinds of fillers. Nevertheless, the seepage depth of molten salt in the multi‐layer fillers diminishes with the increase of the thickness of the sand or gravel layer. The results obtained from this research would be helpful for the engineering design of storage tank foundations and reduce economic losses and the complexity of accident handling.