System and method of removing thermal degradation products from heat transfer fluids

Abstract

A system and method removes thermal decomposition components from biphenol and/or diphenyl oxide heat-transfer fluids. Light, volatile decomposition components such as benzene, water, hydrogen and phenol are passed out of the system for vapor recovery, chemical adsorption or thermal decomposition. Dimerized and polymerized heavy components such as biphenyl phenyl ether, terphenyl and isomers of each are concentrated and recovered for reprocessing and purification for reuse. The system can be operated as either a continuous, semi-continuous or batch operation. Solar electric plants employing the system can use solar field fluids and heating to operate the system during generator operation hours. A wash system operating at or near atmospheric pressure concentrates heavy thermal decomposition components while allowing light, volatile decomposition components to be removed for separation from the majority of the thermal fluid components. Temperature-controlled condensation of the majority of the thermal fluid components allows collection of the thermal fluid, while allowing light, volatile decomposition components to be removed from the system prior to vent processing.

Dependencies are inferred from the claim text.