Heavy crude naphtha

Binuclear aromatic hydrocarbons are found in heavier fractions than naphtha. Trinuclear and polynuclear aromatic hydrocarbons, in combination with heterocyclic compounds, are major constituents of heavy crudes and crude residues. Asphaltenes are a complex mixture of aromatic and heterocyclic compounds. The nature and structure of some of these compounds have been investigated. The following are representative examples of some aromatic compounds found in crude oils ... 

By reforming paraffins and naphtenes present in naphtha into isoparaffins and aromatics the octane number is greatly improved. The main product of the conversion of heavy crude oil fractions in a catalytic cracker is gasoline. 

Catalytic HDT is a fundamental refining process for the upgrading of a wide variety of streams, ranging from straight-run naphtha to vacuum residue (VR) or even heavy and extra-heavy crude oils. The HDT process is commonly employed for... 

One of the important functions of a crude unit is to meet the flashpoint specification for the jet fuel product. This is best done by varying the steam rate to the jet fuel stripper. However, the operators on this crude unit were adjusting the heavy virgin naphtha draw rate to meet the jet fuel flash spec. 

Crude oil distillation column Separates crude oil Into light and heavy components Naphtha, jet fuel, diesel, residue... 

We use a total of 233 different data points containing laboratory measured chemical composition and bulk property information (distillation curve, density, refractive index and viscosity) for light naphtha, heavy naphtha, kerosene, diesel and VGO. These data points come from various plant measurements made over the six-month period of this study and a variety of light and heavy crude assay data (spanning several years) available to the refinery. 

Properly speaking, steam cracking is not a refining process. A key petrochemical process, it has the purpose of producing ethylene, propylene, butadiene, butenes and aromatics (BTX) mainly from light fractions of crude oil (LPG, naphthas), but also from heavy fractions hydrotreated or not (paraffinic vacuum distillates, residue from hydrocracking HOC). 

General Fuel Type True Distillate Naphthas Blended Heavy Distillates Low-Ash Crudes Residuals High-Ash Crude... 

The heavy naphtha-Ught gas oil fractionation zone of a crude tower has to be revamped to handle 25% more capacity. Because trays would be working at high percent flooding, Gempak structured packing is condensed (Figures 9-56A-D). 

Saturated cyclic hydrocarbons, normally known as naphthenes, are also part of the hydrocarbon constituents of crude oils. Their ratio, however, depends on the crude type. The lower members of naphthenes are cyclopentane, cyclohexane, and their mono-substituted compounds. They are normally present in the light and the heavy naphtha fractions. Cyclohexanes, substituted cyclopentanes, and substituted cyclohexanes are important precursors for aromatic hydrocarbons. 

A modern refinery is a complicated collection of conversion processes, each tailored to the properties of the feed it has to convert. The scheme shown in Fig. 9.1 summarizes the most important operations some reasons for these processes are given in Tab. 9.2, along with relevant catalysts. First the crude oil is distilled to separate it into fractions, varying from gases, liquids (naphtha, kerosene and gas oil), to the heavy residue (the so-called bottom of the barrel ) that remains after vacuum distillation. 

The Japanese, who are veiy concerned about air pollution, are investigating floating petroleum refineries. These plants would take on crude oil and produce liquefied petroleum gas (LPG), naphtha, kerosene, and heavy oil while en route to Japan. A conventional tanker would accompany this ship. Both ships would load up with crude and after the refinery ship had processed its own load it would be transferred on the high seas to the tanker, which would transfer its crude to the floating refinery. By the time they reached their destination all the crude would be processed. 17 Any air pollution would occur on the high seas and not directly affect man. 

No. 6 fuel oil (also called bunker C or residual fuel oil) is the residual from crude oil after the light oil, gasoline, naphtha. No. 1 fuel oil, and No. 2 fuel oil have been distilled. No. 6 fuel oil can be blended directly to heavy fuel oil or made into asphalt. It is limited to commercial and industrial uses where sufficient heat is available to fluidize the oil for pumping and combustion. 

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