Enhanced purge effect in gas conduit

The present invention provides an improved gas transfer apparatus designed for enhanced purging of a pigtail and a process for effecting such purging. The improvement in the apparatus resides in an integrated system of components comprising: a surge chamber having a first end, a body and a second end, said first end in communication with the pigtail conduit, said body section of said surge chamber having a cross-section larger than the cross-section of said pigtail conduit and a second end in communication with said vessel containing said gas source; and, a purge gas source for delivery of a purge gas to said pigtail conduit whereby during an alternating cycle of pressurization of said pigtail with said purge gas and depressurization, optionally with application of vacuum within said pigtail conduit, impurities can be removed from within the pigtail conduit.