Petroleum refinery crude-residue

Petroleum refinery crude-residue vacuum towers i Flash evaporators used to produce concentrated orange juice... 

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. 

Aquaconversion A process for converting heavy crude petroleum oils and residues into lighter products, which are more easily converted into more valuable products in oil refineries. Intended for use at the well head rather than the oil refinery. Three steps are involved thermal dissociation of aromatics, dissociation of water giving hydrogen atoms, and addition of these hydrogen atoms to the aromatic fragments to prevent their association. Developed by Foster Wheeler USA Corporation, Intevep, and UOP from 1998. First commercialized in Curacao, Peru, in 1996. 

Some heavy residual fractions from petroleum refineries have been added to FCC unit feeds since the late 1970s, when crude oil prices rose sharply. The processing of these more intractable fractions has partly compensated for the higher oil price without the need to process more erode. Although some new units have been designed to be able to cope with 100% residue, it is more usual to add about 30% of residue to gas oil feeds in conventional units (see Table 5.2). 

OCET [Opti-Crude Enhancement Technology] A process for converting residual refinery oil into petroleum distillates and a coal substitute. A pulsed electric field is applied to the oil. Developed by SGI International in 1996 and expected to be commercialized by 1998. 

In 1979 sulfur obtained as a by-product from petroleum refining accounted for 19.7 percent of total sulfur produced in the U.S. The requirement to desulfurize residual fuels or alternatively to refine them to finished transportation fuels will result in a substantial increase in sulfur produced at refineries even if medium sweet crudes continue to be the primary refinery feedstock. However, most experts predict that crudes will become sourer in the future. The contribution from natural gas is an additional uncertainty. Conventional wisdom predicts that natural gas demand will maintain current levels or possibly decline over the next 20 years. The combination of these factors may increase conventional by-product sulfur from petroleum and natural gas by a factor of three or more by the year 2000. This would bring its sulfur contribution up to approximately 12 million tons by 2000, the same as that predicted by the MITRE estimate for synthetic fuels sulfur production. Thus, a possible total contribution of 60 percent of projected sulfur demand could be met by the combination of these by-product sources of sulfur. 

Residual Fuel Oils—Topped crude petroleum or viscous residuums obtained in refinery operations. Commercial grades of burner-fuel oils Nos. 5, and 6 are residual oils and include Bunker fuels. 

Petroleum coke is produced at oil refineries as a method for disposal of very heavy low-value residual fractions of crude oil to... 

Several of the commercial simulation programs offer preconfigured complex column rigorous models for petroleum fractionation. These models include charge heaters, several side strippers, and one or two pump-around loops. These fractionation column models can be used to model refinery distillation operations such as crude oil distillation, vacuum distillation of atmospheric residue oil, fluidized catalytic cracking (FCC) process main columns, and hydrocracker or coker main columns. Aspen Plus also has a shortcut fractionation model, SCFrac, which can be used to configure fractionation columns in the same way that shortcut distillation models are used to initialize multicomponent rigorous distillation models. 

Residual fuel oil is a natural and significant product of crude oil. A yield of 50% residual fuel oil can be derived from typical or average crudes and a yield of 25% remains after mild or moderate petroleum refining. The average residual fuel oil yield in U.S. refineries is 5-6%. The lack of residual fuel oil production in the U.S. is a result of high conversion or severe refinery processing in a complex refinery configura-... 

Sulfur is naturally present in many crude oils and petroleum fractions, most commonly as organic sulfides and heterocyclic compounds. Residual fuel oils are variable products whose sulfur contents depend not only on their crude oil sources but also on the extent of the refinery processing received by the fuel oil blending components. Sulfur, present in these fuel oils in varying amounts up to 4 or 5% w/w, is an undesirable constituent, and many refining steps aim to reduce the sulfur content to improve stability and reduce environmentally harmful emissions. 

---