Refinery and Distillation Processes

Phases of processing other than heavy-oil distillation processes are discussed in many chapters, particularly under treating (Chaps. 10-11), dewaxing (Chap. 12), thermal cracking (Chap. 19), chemical manufacture (Chap. 20), catalytic cracking and reforming (Chap. 21), and natural gasoline (Chap. 22). 

High temperatures also result in a loss of heavy lubricating-oil stock. The yield of lubricating oils is often decreased by 10 to 15 per cent by the use of too high temperatures. A mild decomposition takes place in which light lubricating oil and gas oil are produced from the heavy stocks. 

Treated pressure distillate is particularly sensitive to high temperatures. Redistillation should not be conducted at temperatures exceeding 375 F, and many refiners find that a ma-ximum temperature of 275°F is economical because of the reduction in treating costs. 

In the manufacture of asphalt most refiners limit the temperature to 770 F. Nevertheless, the temperature that may be used without ruining the ductility of the product is greatly dependent upon the characteristics of the stock and upon the manner of heating. One refiner has successfully used a temperature of 835 F at the pipestill outlet, but others have 

More material can be vaporized (at a given temperature) by a single flash vaporization than by several flashes, and hence the use of a single multidraw tower (Fig. 7-7) is better in this respect than the series arrangements of Fig. 7-2a and 6. Refer to Chap. 15 for a mathematical discussion of methods of vaporization. 

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One of the most important operations in a refinery is the initial distillation of the crude oil into its various boiling point fractions. Distillation involves the heating, vaporization, fractionation, condensation, and cooling of feedstocks. This subsection discusses the atmospheric and vacuum distillation processes which when used in sequence result in lower costs and higher efficiencies. This subsection also discusses the important first step of desalting the crude oil prior to distillation. 

Extraction (discussed in Chapter 5) uses the selective adsorption of a component in a liquid to separate specific molecules from a stream. In application extraction may be coupled with its cousins, extractive distillation and azeotropic distillation, to improve extraction efficiency. Typical refinery extraction applications involve aromatics recovery (UDEX) and lubricants processing (furfural, NMP). Extractive distillation and azeotropic distillation are rarely employed in a refinery. The only... 

Natural gas and crude oils are the main sources for hydrocarbon intermediates or secondary raw materials for the production of petrochemicals. From natural gas, ethane and LPG are recovered for use as intermediates in the production of olefins and diolefms. Important chemicals such as methanol and ammonia are also based on methane via synthesis gas. On the other hand, refinery gases from different crude oil processing schemes are important sources for olefins and LPG. Crude oil distillates and residues are precursors for olefins and aromatics via cracking and reforming processes. This chapter reviews the properties of the different hydrocarbon intermediates—paraffins, olefins, diolefms, and aromatics. Petroleum fractions and residues as mixtures of different hydrocarbon classes and hydrocarbon derivatives are discussed separately at the end of the chapter. 

Fluid catalytic cracking is one of the most important conversion processes in a petroleum refinery. The process incorporates most phases of chemical engineering fundamentals, such as fluidization, heat/mass transfer, and distillation. The heart of the process is the reactor-regenerator, where most of the innovations have occurred since 1942. 

Unrefined waste-derived fuels and oils Fuels produced at a petroleum refinery from oilbearing hazardous wastes that are introduced into the refining process after the distillation step or that are reintroduced in a process that does not include distillation are exempt if the resulting fuel meets the specifications under the federal recycled used oil standards. Oil that is recovered from hazardous waste at a petroleum refinery and burned as a fuel is also exempt provided it meets the used oil specifications. 

MOGD [Mobil olefine to gasoline and distillate] A process for converting C2- to C10-olefins to high-octane gasoline and other hydrocarbons. Developed by Mobil Corporation and first used at its refinery at Paulsboro, NJ, in 1982. 

Refinery Vacnnm Prodncing Systems, Wastewater Separators, and Process Unit Tnmaronnds SOCMI Air Oxidation Processes SOCMI Distillation Operations and Reactor Processes Tank Trnck Gasoline Loading Terminals Fnels... 

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