- FLEXICOKING™ is an Exxon technology
- FLEXICOKING™ is a commercially proven, continuous ﬂuid bed technology that thermally converts heavy oils (such as vacuum resid, atmospheric resid, oil sands bitumen, heavy whole crudes, deasphalter bottoms, or FCC bottoms) to lighter more valuable products. FLEXICOKING is an integrated process that provides greater ﬂexibility when upgrading residuum, producing both clean liquid products as well as a fuel gas or natural gas substitute. FLEXICOKING essentially eliminates petroleum coke production, while providing an economical fuel for reﬁnery furnaces and boilers.
- Feed (typically 1050°F/565°C-plus vacuum resid) enters the scrubber for integrated direct contact heat exchange with reactor overhead efﬂuent vapors.
- The scrubber condenses higher boiling hydrocarbons in the reactor efﬂuent (typically > 975°F/525°C) and recycles these along with the fresh feed to the reactor. Lighter overhead vapors are sent to conventional fractionation and light ends recovery.
- In the reactor, feed is thermally cracked to a full range of liquid products and coke.
- Coke inventory is maintained by transferring bed coke from the reactor to the heater via a transfer line.
- Hot coke from the heater is circulated back to the reactor (through coke transfer line), supplying the heat necessary to maintain reactor temperature and to sustain thermal cracking reactions. Excess coke is sent to the gasiﬁer where the coke reacts with air and steam to produce a clean fuel gas (Flexigas) that can be used in boilers and furnaces, backing out purchased fuel gas.
- Approximately 97% of the coke generated in the reactor is consumed in the process, with a small amount of product coke recovered from the ﬁnes system (5).