Using molten salt as a heat carrier has real advantages, especially in the temperature range from 120 °C to 550 °C, compared to thermal oils, which are limited to an operating temperature of approximately 400 °C. Salt mixtures are liquid under such operating conditions and have advantages such as low viscosity, high heat capacity and pressureless operation. Self-draining systems also ensure high levels of operational safety. Cooling modules that cool down salt mixtures close to their setting point, accurately to within one degree, can also be fitted as needed. This makes it possible to realize a temperature control system with a unique working temperature range. This is not possible using other heat carriers. Application areas include, for example, aluminum dioxide or melamine production as well as lye evaporation and various high-temperature reactions.
Functional diagram of a temperature control system using liquid salt as a heat carrier
Temperature control systems that use liquid salt as a heat carrier have a heated floor tank equipped with a submersible pump. When the pump is switched off, the salt mixture is fed back into the tank to prevent salt from solidifying in the plant. The salt pump conveys the heat carrier to the heater, which can be an electric heater or a fuel-fired boiler, where the salt mixture is heated to the required temperature. An installed air or water cooler can be used to cool down the heat carrier to any temperature above its solidification point.