Noun
One who, or that which, upgrades.
A facility that upgrades bitumen into synthetic crude oil.
Source: en.wiktionary.orgAHS is a partially upgraded dilbit produced from the Scotford Upgrader. Source: Internet
The start of the turnaround at the Upgrader closely follows the end of the four-week turnaround at the Husky Asphalt Refinery that generated specific economic spinoffs. Source: Internet