Petroleum differences

Heavy oil is another type of petroleum, different from conventional petroleum insofar as the flow properties are reduced. A heavy oil is much more difficult to recover from the subsurface reservoir. These materials have a high viscosity and low API gravity relative to the viscosity and API gravity of conventional petroleum (Fig. 1) (3,4), and recovery of heavy oil usually requires thermal stimulation of the reservoir. 

Exposure of various invertebrate species to high concentrations of petroleum did not induce mixed function oxidase activity. Enzyme activity was stimulated, however, in a number of fish tissues by petroleum. Different permutations can be addressed as to the significance of basal or induced levels of mixed function oxidases and hydrocarbon toxicity. AHH may have a physiological role in enhancing hydrocarbon clearance but may also increase the mutagenic-carcinogenic potential of hydrocarbons. Both of these concepts have been demonstrated in studies with fish (29,30). Induced AHH levels may permit a more rapid oxidative transformation with concomitant "disappearance" of parent hydrocarbons, but potentially toxic metabolites could be retained in tissues for longer periods (31). It is likely that at the enzymic level the... 

This paper presents a survey of our present knowledge of the composition of petroleum. Included in the presentation is a brief discussion of the nonhydrocarbon constituents of petroleum, covering sulfur, nitrogen, oxygen, and metallic constituents, together with more detailed information regarding the hydrocarbon constituents which comprise the bulk of crude petroleum. In addition to a discussion of the hydrocarbon compounds and types of hydrocarbon compounds occurring in one representative petroleum, the problem is considered of how different crude petroleums differ in their composition with respect to the hydrocarbon components. 

Petroleums differ considerably in composition depending on their source. However, a representative petroleum1 on distillation yields the following fractions ... 

The petroleum oil which is found in the Caucasus in the region of the Black Sea and commonly known as Russian petroleum differs from American petroleum in that while the latter contains almost entirely hydrocarbons of the aliphatic series, the former contains hydrocarbons known as naphthenes which are hydrogenated benzene compounds. 

Petroleum differs in its physical and chemical characteristics from deposit to deposit. Some crude oils are extremely thick and viscous, while others are light and volatile. The lighter fractions of petroleum evaporate relatively quickly when spilled into the environment. This leaves behind residues of relatively heavy molecules that are more persistent in terrestrial or aquatic habitats, and cause longer-lasting effects. 

The main drivers of this growth are consumer demand for environment-friendly products and the volatile price of petroleum, different policies enforced in different countries that support the increase use renewable sourced raw materials [e.g.. Lead Market Initiative for Bio-based Products] or directives for sound environment-friendly end of life [e.g., European Directive on waste [2008/98/CE] and packaging and packaging waste [94/62/CE and 2004/12/CE]]. 

Table 8.1 Comparison of Industry and Insurance Spacing Tables Spacing Insurance Petroleum Difference Average...

The complexity of petroleum products raises the question of sample validity is the sample representative of the total flow The problem becomes that much more difficult when dealing with samples of heavy materials or samples coming from separations. The diverse chemical families in a petroleum cut can have very different physical characteristics and the homogeneous nature of the cut is often due to the delicate equilibrium between its components. The equilibrium can be upset by extraction or by addition of certain materials as in the case of the precipitation of asphaltenes by light paraffins. 

Mass spectrometry allows analysis by hydrocarbon family for a variety of petroleum cuts as deep as vacuum distillates since we have seen that the molecules must be vaporized. The study of vacuum residues can be conducted by a method of direct introduction which we will address only briefly because the quantitative aspects are ek r metiy difficult to master. Table 3.6 gives some examples the matrices used differ according to the distillation cut and the chemical content such as the presence or absence of olefins or sulfur. 

Knowledge of physical properties of fluids is essential to the process engineer because it enables him to specify, size or verify the operation of equipment in a production unit. The objective of this chapter is to present a collection of methods used in the calculation of physical properties of mixtures encountered in the petroleum industry, different kinds of hydrocarbon components, and some pure compounds. 

From the analytical results, it is possible to generate a model of the mixture consisting of an number of constituents that are either pure components or petroleum fractions, according to the schematic in Figure 4.1. The real or simulated results of the atmospheric TBP are an obligatory path between the experimental results and the generation of bases for calculation of thermodynamic and thermophysical properties for different cuts. 

This relation is used only for temperatures greater than 0°C. The average error is about 5 kJ/kg. Figure 4.5 gives the enthalpy for petroleum fractions whose is 11.8 as a function of temperature. For K, factors different from 11.8, a correction identical to that used for Cpi is used (to... 

The Reid vapor pressure is generally barely different from the true vapor pressure at 37.8°C if the light gas content —methane, ethane, propane, and butane— of the sample is small, which is usually the case with petroleum products. The differences are greater for those products containing large quantities of dissolved gases such as the crude oils shown in Table 4.13. 

This category comprises conventional LPG (commercial propane and butane), home-heating oil and heavy fuels. All these materials are used to produce thermal energy in equipment whose size varies widely from small heaters or gas stoves to refinery furnaces. Without describing the requirements in detail for each combustion system, we will give the main specifications for each of the different petroleum fuels. 

They are classified apart in this text because their use differs from that of petroleum solvents they are used as raw materials for petrochemicals, particularly as feeds to steam crackers. Naphthas are thus industrial intermediates and not consumer products. Consequently, naphthas are not subject to governmental specifications, but only to commercial specifications that are re-negotiated for each contract. Nevertheless, naphthas are in a relatively homogeneous class and represent a large enough tonnage so that the best known properties to be highlighted here. 

From complex cuts characterized in an overall manner, there is a transition towards mixtures containing only a limited number of hydrocarbon families or even compounds. This development has only just begun. It affects for the moment only certain products and certain geographical zones. It is leading gradually to a different view of both refining and the characterization of petroleum products. 

It should be noted that a capital allowance Is not a cashflow item, but is only calculated to enable the taxable income to be determined. The treatment of capital allowance for this purpose is a petroleum economics approach, which may differ from the accountant s view of depreciation when calculating net book values and profit. 

Crude oil (petroleum), a dark viscous liquid, is a mixture of virtually hundreds of different hydrocarbons. Distillation of the crude oil yields several fractions, which are then used for different purposes. 

It has been known since the early 1950s that butadiene reacts with CO to form aldehydes and ketones that could be treated further to give adipic acid (131). Processes for producing adipic acid from butadiene and carbon monoxide [630-08-0] have been explored since around 1970 by a number of companies, especially ARCO, Asahi, BASF, British Petroleum, Du Pont, Monsanto, and Shell. BASF has developed a process sufficiendy advanced to consider commercialization (132). There are two main variations, one a carboalkoxylation and the other a hydrocarboxylation. These differ in whether an alcohol, such as methanol [67-56-1is used to produce intermediate pentenoates (133), or water is used for the production of intermediate pentenoic acids (134). The former is a two-step process which uses high pressure, >31 MPa (306 atm), and moderate temperatures (100—150°C) (132—135). Butadiene,... 

A comparison of the characteristics associated with propellant burning, explosive detonation, and the performance of conventional fuels (see Coal Gas, NATURAL Petroleum) is shown ia Table 1. The most notable difference is the rate at which energy is evolved. The energy Hberated by explosives and propellants depends on the thermochemical properties of the reactants. As a rough rule of thumb, these materials yield about 1000 cm of gas and 4.2 kj (1000 cal) of heat per gram of material. 

There are many different routes to organic chemicals from biomass because of its high polysaccharide content and reactivity. The practical value of the conversion processes selected for commercial use with biomass will depend strongly on the availabiUty and price of the same chemicals produced from petroleum and natural gas. 

Gas oil fractions (204—565°C) from coal Hquefaction show even greater differences in composition compared to petroleum-derived counterparts than do the naphtha fractions (128). The coal-gas oils consist mostly of aromatics (60%), polar heteroaromatics (25%), asphaltenes (8—15%), and saturated... 

Alternative fuels fall into two general categories. The first class consists of fuels that are made from sources other than cmde oil but that have properties the same as or similar to conventional motor fuels. In this category are fuels made from coal and shale (see Fuels, synthetic). In the second category are fuels that are different from gasoline and diesel fuel and which require redesigned or modified engines. These include methanol (see Alcohol fuels), compressed natural gas (CNG), and Hquefted petroleum gas (LPG). 

Hydrocarbons from petroleum (qv) are still the principal energy source for the United States as shown in Table 1. About 60% of the world s energy is supphed by gas and oil and about 27% from coal (6—8). The annual energy demand for oil in different world areas is given in Table 2. 

The dominant role of petroleum in the chemical industry worldwide is reflected in the landscapes of, for example, the Ruhr Valley in Germany and the U.S. Texas/Louisiana Gulf Coast, where petrochemical plants coimected by extensive and complex pipeline systems dot the countryside. Any movement to a different feedstock would require replacement not only of the chemical plants themselves, but of the expensive infrastmcture which has been built over the last half of the twentieth century. Moreover, because petroleum is a Hquid which can easily be pumped, change to any of the soHd potential feedstocks (like coal and biomass) would require drastic changes in feedstock handling systems. 

Lubricants. Petroleum lubricants continue to be the mainstay for automotive, industrial, and process lubricants. Synthetic oils are used extensively in industry and for jet engines they, of course, are made from hydrocarbons. Since the viscosity index (a measure of the viscosity behavior of a lubricant with change in temperature) of lube oil fractions from different cmdes may vary from +140 to as low as —300, additional refining steps are needed. To improve the viscosity index (VI), lube oil fractions are subjected to solvent extraction, solvent dewaxing, solvent deasphalting, and hydrogenation. Furthermore, automotive lube oils typically contain about 12—14% additives. These additives maybe oxidation inhibitors to prevent formation of gum and varnish, corrosion inhibitors, or detergent dispersants, and viscosity index improvers. The United States consumption of lubricants is shown in Table 7. 

The butane-containing streams in petroleum refineries come from a variety of different process units consequently, varying amounts of butanes in mixtures containing other light alkanes and alkenes are obtained. The most common recovery techniques for these streams are lean oil absorption and fractionation. A typical scheme involves feeding the light hydrocarbon stream to an absorber-stripper where methane is separated from the other hydrocarbons. The heavier fraction is then debutanized, depropanized, and de-ethanized by distillation to produce C, C, and C2 streams, respectively. Most often the stream contains butylenes and other unsaturates which must be removed by additional separation techniques if pure butanes are desired. 

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