Coker Gas Oil and Petroleum Coke: Vacuum Residue Delayed-Coked at about 920 °F (Gulf, US 3,071,535)

The black residue from the bottom of the vacuum tower still holds gas oil. Heated to about 920 °F and held in a coking drum, it cracks into lighter oils and coke; the coke stays on the drum walls and the oils go to a fractionator. Result (Gulf's example, per day): from 17,000 barrels of vacuum bottoms, 7,890 barrels of coker gas oil boiling above 400 °F, 4,354 of coker naphtha, light gases and 925 tons of petroleum coke. Source: Condrasky & Glazier, US 3,071,535 (Gulf, filed 1959), Table I. Not given: drum size, pressure, cycle time. Hot oil: fire risk. Picture drawn by Youblob.