The Refinery pulled feed and shut the unit down; the tower and associated equipment was drained and then a push-through with LCO (or Gasoil), followed by a final push with H2O. A brief steam-out is optional. Adaptor spool-pieces were connected and temporary recirculation pipe-work was installed. The tower was filled to 20% of total volume, and heat applied by steam injection to raise the temperature to 70-80 C. TK-121 was added to create a temporary emulsion and then circulated water for 8 to 10 hours recirculation. The emulsion was then drained and the tower filled with a fresh batch of water, with no steam addition to rinse and cool the tower down. The tower was emptied again by draining the rinse water off. The Tower was then ready for man-way opening and LEL/H2S and Benzene gas testing. Safe conditions were confirmed and man-entry proceeded, to commence internal maintenance work.

TOTAL: 28-32 hours