METHOD FOR IMPREGNATION TREATMENT IN SUPERCRITICAL CARBON DIOXIDE, IMPREGNATED PRODUCT BY THE METHOD AND IMPREGNATION TREATMENT SYSTEM

摘要

PPROBLEM TO BE SOLVED: To provide a method for impregnation treatment in supercritical carbon dioxide designed to reduce mixing air or moisture into the carbon dioxide when a base material is to be impregnated with an impregnant in the supercritical carbon dioxide. PSOLUTION: The method comprises the following process: After the base material is charged into an impregnation treatment tank 10 in air, a door 11 is closed to seal up the tank 10. Air is evacuated from the tank 10 with a vacuum pump 14 followed by introducing carbon dioxide into the tank 10 and the impregnation treatment is carried out in the supercritical carbon dioxide. After the impregnation treatment, the impregnant is removed in a gas separation tank 31, the carbon dioxide compressed by a compressor 34 is recovered and stored in a storage tank 40. Thereby, air mixing into the recovered carbon dioxide can be reduced. Furthermore, after reaching a specified depressurization degree, harmful effects of moisture present in the impregnation treatment can also be prevented by either heating the base material while continuing the evacuation operation followed by introducing carbon dioxide or charging the tank 10 with the base material subjected to drying treatment in advance. PCOPYRIGHT: (C)2005,JPO&NCIPI