Reference gas oil

Reference Gas Oil No. 1—A reference sample, that has been analyzed by laboratories participating in the test method cooperative study. Consensus values for the boiling range distribution of this sample are given in Table 3. 

Reference Gas Oil Analysis— The Reference Gas OU No. 1 sample is used to verify both the chromatographic and calculation processes involved in this test method. Perform an analysis of the Gas Oil following the analysis sequence protocol. Collect the area slice data and provide a toiling point distribution report as in Sections 12 and 13. 

Perform this reference gas oil confirmation test at least once per day or as often as required to establish confidence in consistent compliance with 10.4.1. 

The fuel vacuum pipe still is also used to recover cracked gas oil from the tar formed in residuum cracking (visbreaking) processes. In this service, it it frequently referred to as a vacuum, flash unit. Pipe stills designed for the production of asphalt are usually the fuel type of unit. 

Primary separation facilities process the produced fluids and gases into individual streams of gas, oil and water. These facilities are commonly referred to as Gas Oil Separation Plants (GOSP s), Central Processing Facilities (CPF) or if located offshore on drilling, production and quarters platforms (PDQ s). The offshore platform may either float on the sea or be supported on steel or concrete supports secured to the ocean floor, where it is capable of resisting waves, wind, and in Arctic regions ice flows. In some instances surplus oil tankers have been converted into offshore production and storage facilities. 

A plot of boiling temperatures (°F) vs. cumulative percent volume removed from the sample is referred to as a distillation curve. The boiling temperatures for various products range from high to low divided into the following product types residue, heavy gas-oil, light gas-oil, kerosene, naphtha, gasoline, and butanes (Table 4.4). 

Traditional olefin plants have more than one alias. One is even fraudulent. They are variously called ethylene plants after their primary product steam crackers because the feed is usiuilly mixed with steam before it is cracked or whatever aacker, where whatever is the name of the feed (ethane cracker, gas oil cracker, etc.). Olefin plants are sometimes referred to as ethylene crackers, biit only those who don t know any better, use that misnomer. Ethylene is not cracked but rather is the product of cracking. 

Referring to the hardware in Figure 5—4, there are much larger facilities required for heavier liquids cracking than for ethane or propane. As you saw in Table 5—1, the yield of ethylene from the heavier feeds is much lower than from ethane. That means that to produce the same amount of ethylene on a daily basis, the gas-oil furnaces have to handle nearly five times as much feed as ethane furnaces. As the design engineer scales up these volumes, he or she has to worry about the size of the cubes necessary to heat up that much feed, the residence times best for each kind of feed, and the best pressure/temper-ature/steam mixture conditions. 

The fuel oils coming out of olefin plants are also characterized by an abundance of polynuclear aromatic molecules, (Same definition as for Figure 2—1). They are sometimes inaccurately referred to as having a high aromatics content. Nomenclature aside, because of this, the burning characteristics of pyrolysis gas oil and pyrolysis pitch are poor. They are smoky, sooty, and gum formers they rend to be more viscous, and because of their polynuclear aromatic concent, they are suspected carcinogens. They are basically a witchs brew of unsavory hydrocarbons.. ... 

As discussed in Section III, when the sulfur content is lowered from 0.20 to 0.05%, the chemistry of HDS of gas oils is essentially the chemistry of alkyl-substituted dibenzothiophenes. Though gas oils initially contain mostly alkyl-substituted benzothiophenes, these are completely removed by the time 0.20% S is achieved. Thus, this review will deal predominantly with the reaction pathways involved in the HDS of alkyl-substituted dibenzothiophenes. There are many excellent reviews on reaction pathways of the more reactive sulfur species such as thiophenes and benzothiophenes (2, 5, 8, 23, 24), and the reader is referred to those reviews for information on the reaction pathways and mechanisms of HDS for the more reactive... 

The word oil is used in phrases such as gas-oil ratio, stock-tank oil, oil formation volume factor, and oil compressibility because of common usage in the petroleum industry. In this context, oil simply refers to a petroleum liquid which may be the result of the production of reservoir liquid or condensation from the production of reservoir gas. 

The temperature of a gas oil product flowing through a pipe is monitored using a chromel/alumel thermocouple. The measurement junction is inserted into the pipe and the reference junction is placed in the plant control room where the temperature is 20°C. The emf at the thermocouple junction is found to be 6.2 mV by means of a potentiometer connected into the thermocouple circuit adjacent to the reference junction. Find the measured temperature of the gas oil. 

The catalytic cracking unit is often referred to as the gasoline workhorse of a refining unit. As shown in Fig. 18.9, feeds to the catalytic cracking unit are gas oils from the atmospheric and vacuum distillation columns and delayed coker. These heavier fractions also carry metals such as nickel, vanadium, and iron. More important, sulfur compounds concentrate in the heavier product fractions. Table 18.8 lists a typical mass balance for sulfur.25 FCC blend-stocks comprise 36 percent of the volume of the gasoline pool. However, this stream also contributes 98 percent of the sulfur concentration to blended procucts.25 As specifications on sulfur concentrations in diesel and gasoline tighten, more efforts are focused on how feeds and product streams from the FCC are pre- and posttreated for sulfur concentrations. 

Through a series of round robin tests conducted by participating laboratories, ASTM Committee D-32 on Catalysts has characterized a variety of catalyst materials using standard test methods. Materials include fluid cracking catalysts, zeolites, silicas, aluminas, supported metals, and a gas oil feedstock. Properties characterized include surface area, crush strength, catalytic microactivity, particle size, unit cell dimensions and metal content. These materials are available from the National Institute of Standards and Technology as reference materials. 

The test requires the use of a standard batch of gas oil as a feedstock and a set of equilibrium fluid cracking catalysts with consensus mean conversion values assigned in a reactor of specified design. The gas oil and the set of equilibrium cracking catalysts are useful reference materials. Conversion for any equilibrium or laboratory-deactivated fluid cracking catalyst can be measured and compared to a conversion calibration curve. Conversion is measured by the difference between the amount of feed used and the amount of unconverted material. The unconverted material is defined as all liquid product with a boiling point above 216°C. 

As well as naphtha, some operations use gas-oil as the feedstoek. Gas oil is the crude oil fraction boiling typically at 220°C to 360°C, and some processing vacuum gas oils boiling typically at 360°C to 550 C. However, in some instances these crackers have been revamped to use the atmospheric column bottoms (sometimes called long residua) where the crude oil being processed has the appropriate properties of high wax (linear paraffin) content and low metal content (which otherwise promotes excessive coke formation). This material is often referred to as Low Sulphur Waxy Residual Fuel Oil (LSWR). 

In many refineries the atmospheric column bottoms are passed to vacuum distillation. This produces vacuum gas oils used primarily to produce lubricating oils. These boil in the range 350 C to about 550°C. The residua from this coluimi, often referred to as short residua or heavy fuel oil, concentrates all of the contaminant metals. 

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