To provide a pretreatment apparatus for painting, which can save the space by shortening a treatment process, can reduce equipment cost, can improve the productivity, and can reduce the cost of treatment agents, the number of treatment steps, and a load on waste water treatment.
This pretreatment apparatus for painting comprises a treatment tank 1 filled with a degreasing and chemical conversion treatment liquid, a first spray zone 24 for separating the liquid contained in the treatment tank 1 by vacuum distillation into a polar organic solvent and water and for spraying the separated polar organic solvent onto a coating object, and a second spray zone 25 for spraying water. The pretreatment apparatus further includes a circulation system 11 for circulating the treatment liquid, (1) a dust removal unit 2 for removing dust contained in the treatment liquid, a chemical conversion sludge removal unit 3 for removing chemical conversion sludge, an oil removal unit 4 for removing oil, (2) a treatment liquid supplying tank for supplying a fresh treatment liquid, (3) a water-polar organic solvent separator 5 for returning the separated polar organic solvent component to the circulation system, and (4) an ion removal unit 7 for removing the ion component from the separated water component and for returning the remaining water to the treatment liquid supply tank 6.
