Sour crude

Since aluminum is not attacked by hydrogen sulfide (HjS) solutions, it is used widely as a material in refineries for the handling of hydrocarbons made from sour crudes. In the strongly oxidizing conditions of manufacturing hydrogen peroxide, aluminum is one of the few materials that does not undergo decomposition. 

Figure 5 Comparison of HNBR with fluoroelastomer (FPM), NBR and XNBR in Sour Crude Oil (sour gas = 20% H2S + 65% CH4 + 15% CO2). Source Bayer AG, Germany.

Coke produced from delayed coking is described as delayed sponge, shot, or needle coke depending on its physical structure. Shot coke is the most common when running the unit under severe conditions with sour crude residues. Needle coke is produced from selected aromatic feedstocks. Sponge coke is more porous and has a high surface area. The properties and markets for petroleum cokes have been reviewed by Dymond. Table 3-4 shows the types of petroleum cokes and their uses. ... 

The ER system has been used successfully in a range of industries for process plant monitoring. As ER can be applied in any liquid or gaseous environment the areas of application are considerable. However, there is a problem with ER if a conductive corrosion product is produced as is the case with sour crude oil or gas due to the deposition of iron sulphide. 

Vosikovsky, O., Macecek, M., and Ross, D.J. Allowable defect sizes in a sour crude oil pipeline for corrosion fatigue conditions, International Journal of Pressure Vessels and Piping, 13,197-226,1983. 

Sour crude oil crude oil containing an abnormally large amount of sulfur compounds. 

Wastewater from crude oil fractionation generally comes from three sources. The first source is the water drawn off from overhead accumulators prior to recirculation or transfer of hydrocarbons to other fractionators. This waste is a major source of sulfides and ammonia, especially when sour crudes are being processed. It also contains significant amounts of oil, chlorides, mercaptans, and phenols. 

Hydrotreating reduces the sulfur content of product streams from sour crudes by 90% or more. Nitrogen removal requires more severe operating conditions, but generally 80% reductions or better are accomplished. 

Hydrogen sulfide and mercaptans Sour crudes formed by decomposition of sulfur compounds during distillation, cracking, reforming, and hydroprocessing... 

The production of domestic sulfur values (elemental recovered sulfur and the sulfur content of acid) will total about 18 million long tons per year by the year 2000. By region (Petroleum Administration for Defense districts), except for the east coast (PAD I), there will be no deficit areas in the U. S. Major contributors are sour natural gas and the refining of heavier, sour, crude oil. Proximate, scenario dependent sources, are electric utilities and coal-based synfuels. Shale oil, domestic tar sands and heavy oil, and unconventional sources of natural gas will be small suppliers. 

All the obstacles in the path of distillation progress, however, were not equipment fabrication and design problems. It was discovered very early in the running of sour crudes that the shell still corroded severely at the vapor-liquid interface line and in that portion of the shell in contact with vapors. At the same time severe corrosion in pipe stills and tube stills, along with overheating and coking, resulted in expensive equipment failures. These problems started metallurgists on a chain of developments which produced the corrosion- and heat-resistant alloys used in modern oil heaters and the alloy liners used in distillation columns. 

Most natural organic materials which have strong odors, either agreeable or disagreeable, contain either mercaptans or alkyl sulfide. Various mercaptans have been found in crude oil, and the odor contributed by small quantities of these materials led to the name sour crude. 

Sour crude oil - [PETROLEUM - REFINERY PROCESSES, SURVEY] (Vol 18)... 

Similarly, sour crudes, heavy residaums, and oilier peiroleuin-huse starting materials can he hydrogenated, sometimes coupled with oilier processes. to sweeten, reduce viscosity, and otherwise impin e the materials for better use as fuels. See also Coal Hydrotreating and Helruleilm. 

Mercaplans—Compounds of sulfur having a strong, repulsive, garliclike odor. A contaminant of "sour crude oil and products. 

Sour Crude—Crude oil which (1) is corrosive when heated. (2) evolves significant amounts of hydrogen sulfide on distillation, or (3) produces light fractions which require sweetening. Sour crudes usually, but not necessarily, have high sulfur content. Examples are most West Texas and Middle East crudes. 

Ci uuc oil—complex, naturally occurring fluid mixture of petroleum hydrocarbons, yellow to black in color, and also containing small amounts of oxygen, nitrogen, and sulfur derivatives and other impurities. Crude oil was formed by the action of bacteria, heat, and pressure on ancient plant and animal remains, and is usually found in layers of porous rock such as limestone or sandstone, capped by an impervious layer of shale or clay that traps the oil (see reservoir). Crude oil varies in appearance and hydrocarbon composition depending on the locality where it occurs, some crudes being predominately naphthenic, some paraffinic, and others asphaltic. Crude is refined to yield petroleum products. See distillation, hydrocarbon, sour crude, sweet crude, asphalt, naphthene, paraffin. 

Sweet crude oil crude oil containing little sulfur see also Sour crude oil. 

The process data can now be translated into refinery processing configurations. Figure 8 is a schematic diagram of a typical sour crude refinery. While we realize that there is no such thing as a typical refinery, and many American refineries are not sour crude refineries, this figure represents what we believe to be a reasonable approximation of the type of refinery that will be operating in the United States in 1990. 

Figure 8. Typical American Sour crude refinery...

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