Abstract: A system and method removes thermal decomposition components from biphenyl and/or diphenyl oxide-based heat transfer fluids. Light, volatile decomposition components including benzene, water, hydrogen and phenol leave the system for vapor recovery, chemical adsorption or thermal decomposition. Dimerized and polymerized heavy components such as biphenyl phenyl ether, terphenyl and related isomers are concentrated and recovered. The system can be 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 removal of light, volatile decomposition components for separation from the majority of the thermal fluid components.

Abstract: A system and method removes thermal decomposition components from biphenol and/or diphenyl oxide heat-transfer fluids. Light, volatile decomposition components including benzene, water, hydrogen and phenol leave the system for vapor recovery, chemical adsorption or thermal decomposition. Dimerized and polymerized heavy components such as biphenyl phenyl ether, terphenyl and related isomers are concentrated and recovered. The system can be 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 removal of light, volatile decomposition components for separation from the majority of the thermal fluid components.

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.

Abstract: A system is disclosed for reducing the amount of waste water and recovering reusable constituents from a waste stream comprising at least two constituents having different relative volatilities. The system includes a vapor thermocompression evaporator, into which the waste stream is directed, to vaporize one of the constituents within the waste stream without appreciably vaporizing other constituents in the waste stream. The vapor thermocompression evaporator also has a vapor compressor for compressing the vaporized fraction of the first constituent and delivering this compressed vaporized fraction to transfer heat to the waste stream. The system further has a film evaporator in series with the vapor thermocompression evaporator which transfers heat to the stream after it leaves the vapor thermocompression to vaporize substantially all of the first constituent without appreciably vaporizing the second constituent.