Petroleum properties correlations

Equations and property data are included for 39 hydrocarbons, 10 nonhydrocarbons, and petroleum fractions. Petroleum properties are predicted by equations derived from correlations that are in the Technical Data Book of the American Petroleum Institute (1). 

Although crude petroleum contains small amounts of oxygen, nitrogen, and sulfur, its major constituents are hydrocarbons—compounds of carbon and hydrogen. Isolating individual hydrocarbon substances from petroleum mixtures is an industrial process of central importance. Moreover, it provides a fascinating story that illustrates how the structures of molecules determines the properties of substances and the behavior of those substances in particular processes. The next three sections present a brief introduction to this story, emphasizing the structure-property correlations. 

In recent years several studies of the distribution of trace elements in U.S.S.R.petroleums and correlations with geochemical properties have been made. Kotova, et showed that V, Ni, Cu,... 

Several books have been published during the years, dealing with detailed explanations about the physical and chemical characterization of petroleum (Speight, 1999, 2001) as well as methods and correlations for prediction of petroleum properties (Riazi, 2004). Therefore, this section will not describe in detail all the properties of heavy crude oils, but only those relevant issues that need to be taken into consideration when processing these heavy materials. First, a general overview of the most common physical and chemical properties is summarized. And later, more details are given on those properties and how to calculate them that are crucial for heavy petroleum. 

Experience has shown that certain carefully selected physical properties could be correlated with the dominant composition of a petroleum cut or crude oil. 

Seam correlations, measurements of rank and geologic history, interpretation of petroleum (qv) formation with coal deposits, prediction of coke properties, and detection of coal oxidation can be deterrnined from petrographic analysis. Constituents of seams can be observed over considerable distances, permitting the correlation of seam profiles in coal basins. Measurements of vitrinite reflectance within a seam permit mapping of variations in thermal and tectonic histories. Figure 2 indicates the relationship of vitrinite reflectance to maximum temperatures and effective heating time in the seam (11,15). 

Distillation appHcations can be characterized by the type of materials separated, such as petroleum appHcations, gas separations, electrolyte separations, etc. These appHcations have specific characteristics in terms of the way or the correlations by which the physical properties are deterrnined or estimated the special configurations of the process equipment such as having side strippers, multiple product withdrawals, and internal pump arounds the presence of reactions or two Hquid phases etc. Various distillation programs can model these special characteristics of the appHcations to varying degrees and with more or less accuracy and efficiency. 

The difficulties encountered in the Chao-Seader correlation can, at least in part, be overcome by the somewhat different formulation recently developed by Chueh (C2, C3). In Chueh s equations, the partial molar volumes in the liquid phase are functions of composition and temperature, as indicated in Section IV further, the unsymmetric convention is used for the normalization of activity coefficients, thereby avoiding all arbitrary extrapolations to find the properties of hypothetical states finally, a flexible two-parameter model is used for describing the effect of composition and temperature on liquid-phase activity coefficients. The flexibility of the model necessarily requires some binary data over a range of composition and temperature to obtain the desired accuracy, especially in the critical region, more binary data are required for Chueh s method than for that of Chao and Seader (Cl). Fortunately, reliable data for high-pressure equilibria are now available for a variety of binary mixtures of nonpolar fluids, mostly hydrocarbons. Chueh s method, therefore, is primarily applicable to equilibrium problems encountered in the petroleum, natural-gas, and related industries. 

Unfortunately the literature is rampant with data obtained from cyclones of so wide a variety of deviating dimensional ratios and ill defined particle properties, sizes and loadings, that full agreement between designers, theorists and practitioners has not yet been achieved. However, in practice, the enormous number of cyclones installed in identical industrial process applications in the petroleum and petrochemical industries (Zenz, A P I., 1975) throughout the world and spurred by a common interest in economics and environmental regulations, has led to the correlations shown as the solid curves in Figs. 2 and 3. 

Thus, initial inspection of the nature of the petroleum will provide deductions about the most logical means of cleanup and any subsequent enviromnental effects. Indeed, careful evaluation of petroleum from physical property data is a major part of the initial study of any petroleum that has been released to the enviromnent. Proper interpretation of the data resulting from the inspection of crude oil requires an understanding of their significance. Consequently, various standards organizations, such as the American Society for Testing and Materials (ASTM, 2004) in North America and the Institute of Petroleum in the United Kingdom (IP, 2004), have devoted considerable time and effort to the correlation... 

The hydrogen content, heat of combustion, specific heat, and thermal conductivity data herein were abstracted from Bureau of Standards Miscellaneous Publication 97, Thermal Properties of Petroleum Products. These data are widely used, although other correlations have appeared, notably that by Linden and Othmer (Chem. Eng. 54[4, 5], April and May, 1947). 

Stenzel H, Rodicker H. 1991. Results of substance groups and structural groups analysis of petroleum fractions and their application in estimating the correlation for predicting properties. Chemische Technik 43 344-346. 

Atlanta,18-21 April 1988,p.733-7. 012 STRUCTURE-PROPERTY RELATIONSHIP AND ITS CORRELATION WITH THERMAL BEHAVIOUR OF CROSSLINKED EXPANDED EVA FORMULATION Hadjiandreou P Zitouni F ALGERIAN INSTITUTE OF PETROLEUM (SPE)... 

The insecticidal efficiency under laboratory conditions of various members of two series of narrow boiling petroleum fractions was determined for adult female California red scale, Aonidiella auranfii (Mask.) and eggs of the citrus red mite, Paratetranychus citri (McG.). Correlations between efficiency and various properties of the fractions such as structural character, molecular weight, and viscosity were observed. These correlations Indicate that conventional spray oils used on citrus in California may contain appreciable amounts of hydrocarbons of low insecticidal activity. The evidence indicates that the insecticidal efficiency of spray oils against citrus insect pests may be considerably improved by proper selection with respect to structural character and molecular size. 

Chapman, Pearce, and Avens (4, 20) investigated the relation between chemical composition and insecticidal efficiency of various dormant and foliage spray oils against several common insect pests of deciduous trees, and found it to be positive. They concluded that an oil which is highly paraffinic in character is the most desirable type. Saturated narrow-cut petroleum fractions were used by Pearce, Chapman, and Frear 21) in a study of the influence of molecular weight and structural constitution on the insecticidal efficiency of such oils to eggs of the oriental fruit moth, Grapholitha molesta (Busck). Correlations between efficiency and various properties were compared on the basis of composition. The value of paraffinicity was illustrated, and the importance of other properties was indicated. 

This chapter describes several properties of dry gases which commonly are normally used by tire petroleum engineer. We will define each property and then give correlations useful for estimating values of the property using normally available information about the gas. 

Later we will see that K-factors are correlated with a property termed convergence pressure. Convergence pressure will be defined in Chapter 14. The set of K-factor correlations in Appendix A is for use with petroleum mixtures having convergence pressures close to 5000 psia. 

The properties of oilfield waters have not been studied as carefully and systematically as the properties of other fluids of interest to petroleum engineers. Therefore, many of the correlations discussed in this chapter are based on limited data. 

Initially, we will be concerned with the physical properties of alkanes and how these properties can be correlated by the important concept of homology. This will be followed by a brief survey of the occurrence and uses of hydrocarbons, with special reference to the petroleum industry. Chemical reactions of alkanes then will be discussed, with special emphasis on combustion and substitution reactions. These reactions are employed to illustrate how we can predict and use energy changes — particularly AH, the heat evolved or absorbed by a reacting system, which often can be estimated from bond energies. Then we consider some of the problems involved in predicting reaction rates in the context of a specific reaction, the chlorination of methane. The example is complex, but it has the virtue that we are able to break the overall reaction into quite simple steps. 

Thus, initial inspection of the nature of the feedstock will provide deductions about the most logical means of refining or correlation of various properties to structural types present and hence attempted classification of the petroleum... 

Measuring the overall solubility parameter of a petroleum fraction is time-consuming. Therefore, it is desirable to have a simpler, less time-consuming measurement that can be made on petroleum fractions that will correlate with the solubility parameter and thus give an alternative continuum in polarity. In fact, the hydrogen-to-carbon atomic ratio and other properties of petroleum fractions that can be correlated with the solubility parameter (Wiehe, 1992, 1995, 1996 Speight, 1994) also provide correlation for the behavior of crude oils. 

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