Enhanced purge effect in gas conduit

The present invention provides a gas transfer apparatus designed for enhanced purging of a pigtail conduit and a process for effecting such purging. The apparatus comprises a surge chamber having a first end, a body and a second end, the first end in communication with the pigtail conduit. A body section of the surge chamber has a cross-section larger than the cross-section of the pigtail conduit. The second end is in communication with a vessel containing a gas source. The apparatus includes a purge gas source for delivery of a purge gas to the pigtail conduit whereby during an alternating cycle of pressurization of the pigtail conduit with the purge gas and depressurization, impurities can be removed from within the pigtail conduit.