MOSA

Molten Salt Test Loop for Thermal Energy Systems

This molten salt test loop is a replica of a thermal energy storage system with molten salts and a two-tank configuration. With 40t of molten salts plant, this facility consists basically in:

• Two tanks, one vertical, for hot molten salts, and another horizontal, for cold molten salts.
• A thermal oil loop that can be used for heating the salt up to 380oC and cooling it to 290oC.
• A CO2-molten salt heat exchanger for heating the salt up to 500oC with CO2 supplied by parabolic trough collectors.
• Two flanged sections, where different components for this type of loops (e.g. valves, flow meters, heat trace, pumps…) can be tested.

Being a set up which is a reduced scale of a commercial two-tank molten salt storage system, everything related to this type of systems can be tested in this facility.

For more information see:
M. M. Rodríguez-García, and E. Zarza, “Design and Construction of an Experimental Molten Salt Test Loop”, Proceedings of the 17th International SolarPACES Conference, Granada, 2011.

Applications

• Checking of components (pumps, valves, flowmeters, etc.) for their use in a molten salt medium.
• Optimization of procedures in normal operation for a two-tank system configuration.
• Optimization of procedures in risk situations for a two-tank system configuration. Designing recovery procedures.
• Validation of models and simulation approaches for molten salt thermal systems.
• Characterization of heat exchangers for molten salt/oil.
• Characterization of heat exchangers for molten salt/gas.
• Characterization of thermocline tanks.

BES

Materials and components for molten salt storage systems

Molten salts are becoming not only a standard thermal storage medium, but also a working fluid for central receiver solar plants. However, there are still open questions regarding the durability of components and materials currently available at the market for molten salt circuits. Keeping this in mind, a specific activity line was implemented in the laboratory of Concentrating Solar System Unit for this purpose. The equipment associated to this activity is installed indoor at PSA and it is composed of two test benches, BES-I and BES-II (Figure 14) especially designed and manufactured for testing of valves, pressure transmitters and other molten salts components under real working conditions up to 600ºC and 40 bar. Components with a nominal diameters from 2” up to 6” can be evaluated in these test benches.