At least one refinery ship (of Tauranian registry) escaped the Fall of the Twelve Colonies with the Fleet. Refinery ships process raw minerals and metals gathered by a Mining Ship. Unlike a Mining Ship, a Refinery Ship has large processing and storage facilities, and presumably can serve as a fueling vessel.
A Refinery Ship was used to process the immense reserves of tyllium mined from an asteroid liberated from a Cylon base (The Hand of God).
The Tauranian Refinery Ship refused to continue refining tylium in protest of President Laura Roslin's imprisonment and Col. Tigh's subsequent declaration of martial law ("Resistance").
An unnamed refinery ship, referred to as a "tanker", was damaged in a collision with the Striker under the incompetent oversight of recently promoted Captain George Birch, CAG for Galactica in Lee Adama's absence (Home, Part I).
The Dora Mozu was identified as a refinery ship in the episode "Epiphanies".