METHOD AND SYSTEM FOR VACUUM-PURGING GAS IN EXISTING PIPING OR EXISTING TANK

摘要

A method and a system for vacuum-purging gas in existing piping or an existing tank, characterized in that a vacuum pump and an activated charcoal filling container brought in a vacuum state beforehand and having a capacity capable of sufficiently recovering all gas amount from the existing piping or existing tank are connected to a gas outlet tube from the existing piping or the existing tank, gas is adsorbed and recovered by the activated charcoal filling container until a gas pressure in the existing piping or the existing tank is equal to or less than the atmospheric pressure, the vacuum pump is started to discharge the remaining gas into the activated charcoal filling container, a vacuum treatment is completed when an internal pressure between closed sections at both ends of the existing piping or in the existing tank becomes 0 MPa or near 0 MPa, and purge gas is led between the closed sections at both ends of the existing piping or into the existing tank to perform a purge operation. Thus, the gas purge performed when the existing piping or the existing tank is removed or replaced can be easily, safely, and securely performed.