Topping and hydroskimming refineries
The simplest refinery configuration, called a topping refinery, is designed to prepare feedstocks for petrochemical manufacture or for production of industrial fuels in remote oil-production areas. It consists of tankage, a distillation unit, recovery facilities for gases and light hydrocarbons, and the necessary utility systems (steam, power, and water-treatment plants).
Topping refineries produce large quantities of unfinished oils and are highly dependent on local markets, but the addition of hydrotreating and reforming units to this basic configuration results in a more flexible hydroskimming refinery, which can also produce desulfurized distillate fuels and high-octane gasoline. Still, these refineries may produce up to half of their output as residual fuel oil, and they face increasing economic hardship as the demand for high-sulfur fuel oils declines.
The most versatile refinery configuration is known as the conversion refinery. A conversion refinery incorporates all the basic building blocks found in both the topping and hydroskimming refineries, but it also features gas oil conversion plants such as catalytic cracking and hydrocracking units, olefinconversion plants such as alkylation or polymerization units, and, frequently, coking units for sharply reducing or eliminating the production of residual fuels. Modern conversion refineries may produce two-thirds of their output as gasoline, with the balance distributed between high-quality jet fuel, liquefied petroleum gas (LPG), diesel fuel, and a small quantity of petroleum coke. Many such refineries also incorporate solvent extraction processes for manufacturing lubricants and petrochemical units with which to recover high-purity propylene, benzene, toluene, and xylenes for further processing into polymers.
Contact Us to ask a question, provide feedback, or report a problem.