Patent ID: 6893556

Claim:
A pretreatment apparatus for performing pretreatment before a painting process, the pretreatment apparatus comprising: a liquid container section including a treatment section which includes a treatment tank to store a treatment liquid for degreasing and chemical conversion; a circuit section to form a circulation path for circulating the treatment liquid from the treatment tank to the liquid container section; and a purifying section to remove an unwanted constituent from the treatment liquid circulated to the container section through the circulation path, wherein the purifying section is a section to remove dust, chemical sludge and oil, and the purifying section comprises a sludge removing section disposed in the circulation path, and arranged to remove the chemical sludge from the treatment liquid, wherein the liquid container section further comprises a rinse tank disposed at a stage following a stage of the treatment tank, and arranged to store a rinsing liquid, wherein the purifying section comprises: a separating section disposed in the circulation path for circulating the treatment liquid from the treatment tank to the liquid container section, and arranged to receive the treatment liquid and to separate a polar organic solvent and a water content in the treatment liquid, wherein the circuit section comprises a circuit member to form a rise-side circulation path to return the treatment liquid to the rinse tank, and wherein the purifying section further comprises: a dust removing section, disposed in the rise-side circulation path, and arranged to remove dust from the treatment liquid for degreasing and chemical conversion; and an oil removing section disposed in the rise-side circulation path, and arranged to remove an oil content from the treatment liquid.