APPARATUS FOR REGENERATING USED COOLANT LIQUID

PROBLEM TO BE SOLVED: To provide a method which, in recovering low-vapor pressure ethylene glycol from a used coolant stock liquid, can remove contaminants of rust preventive materials, iron, and inorganic salts and ions present as a mixture in the stock liquid. SOLUTION: A mixed vapor composed of ethylene glycol and steam ascends from the lower part to the upper part of a fine wire gauze layer. In this case, the mixed vapor is mixed with low-temperature condensate spread from the upper part for heat exchange. Ethylene glycol having a higher boiling point is condensed on the fine wire gauze, is dropped in a recovered liquid tank and is stored. Meanwhile, water having a lower boiling point is vaporized. The ethylene glycol dropped in the recovered liquid tank is heated with a heater b, or the mixed vapor is blown through a submerged nozzle to heat the ethylene glycol, whereby the ethylene glycol is again vaporized, is again allowed to ascend through the fine wire gauze layer to separate water from ethylene glycol. Ethylene glycol is dropped in the recovered liquid tank in the lower part, while water is withdrawn as steam in the upper part. The steam is then passed through an inner tube in a cooler where the water vapor is cooled with cold air fed from a cooling fan and thus is converted to condensed water which is then dropped in a condensate tank. COPYRIGHT: (C)2008,JPO&INPIT