Crude oil, properties

As a starting point, the book reviews the general properties of the raw materials. This is followed by the different techniques used to convert these raw materials to the intermediates, which are further reacted to produce the petrochemicals. The first chapter deals with the composition and the treatment techniques of natural gas. It also reviews the properties, composition, and classification of various crude oils. Properties of some naturally occurring carbonaceous substances such as coal and tar sand are briefly noted at the end of the chapter. These materials are targeted as future energy and chemical sources when oil and natural gas are depleted. Chapter 2 summarizes the important properties of hydrocarbon intermediates and petroleum fractions obtained from natural gas and crude oils. 

Crude oil at 22°C enters a 20-ciii-diaineler pipe with an average velocity of 20 cm/s. The avenge pipe wall temperature is 2°C. Crude oil-properties are as given below. Calculate the rate of heat transfer and pipe length if the crude oil outlet tem-pera re is 20°C. 

Table 1.1 Variation in crude oil properties between sources...

Lastly, the impact of demulsifier choices and chemistries on petroleum recovery operations are discussed. We conclude with identification of the need for cooperation between research providers, petroleum operations, and chemical suppliers geared towards an effort for full scientific understanding of demulsifica-tion. Examples of crude-oil properties and demulsifica-tion are drawn from over three decades of published results of researchers worldwide. Examples of demul-sification of bitumen W/O emulsions are excerpted from work performed in the author s own laboratory at CANMET. 

The interfacial tension, y, in the Gibbs adsorption equation is used for equilibrium conditions as bitumen components are adsorbed. Measurement techniques available are extensive. Some of these methods are duNouy ring, maximum bubble pressure, drop volume, Wilmhelmy plate, sessile drop, spinning drop, pendant drop, capillary rise, oscillating jet, and capillary ripples. These and many others are referenced extensively by Malhotra and Wasan (153). These authors also showed that there is no correlation between emulsion stability and interfacial tension. The nature of the film dominates stability. Some relationships between interfacial tensions and crude oil properties follow. 

De Silva et al. (278) correlated the RSN with performance information and crude-oil properties to arrive at a predictive tool for choosing demulsifiers. They attempted to... 

Ferritto, T., Crude Oil Properties and their Effect on Linear Programming , Crude Oil Quality Group Meeting, Denver, CO, February 2, 1999. 

The ideal crude oil assay should be able to provide on-line, instantaneous and detailed determination of all crude oil properties across the boiling range. Unfortunately, such a method is not yet available. However, several efforts have been made to that end. The most successful approach has been the prediction of the physicochemical properties of crude oils by correlating the data obtained by a rapid, surrogate method (usually spectroscopic) to the data... 

Predictions from Measurement of Selected Whole Crude Oil Properties... 

Note Some values in table depend upon crude oil properties. Sources [4,5]. 

To obtain the desired information, two different analytical schemes are commonly used, namely, an inspection assay and a comprehensive assay. Inspection assays usually involve determination of a few key whole crude oil properties such as API gravity, sulfur content, and pour point—principally as a means of determining if major changes in a crude oil stream s characteristics have occurred since the last comprehensive assay was performed. Additional analyses may be performed to help ensure that the cargo or shipment received is that which is expected to ascertain the quantity of impurities such as salt, sediment, and water and to provide other critical refinery-specific information. Inspection assays are routinely performed on all shipments received at a refinery. The comprehensive assay, on the other hand, is complex, costly, and time-consuming and is normally performed only when a new field comes on stream, or when the inspection assay indicates that significant changes in the stream s composition have occurred. Except for these circumstances, a comprehensive assay of a particular crude oil stream may not be updated for several years. 

Uses Emulsion breaker for w/o emulsions dehydration agenL desalting agent for crude oil Properties Liq. 

Various classifications of petroleum are reported in the literature, which take into consideration crude oil properties, distillates properties, chemical structure, origin, etc. Given the great amount of effort that experts around the world have put into these definitions, it is not necessary to generate new criteria. 

The same Maya crude oil was used as feedstock. More details of Maya crude oil properties and its classification respect to other crudes according to the content of metals, sulfur, and API gravity were reported by Rana et al. (2007). The same NiMo/ AI2O3 commercial catalyst, loading and sulfiding procedures, as well as characterization techniques were also used. Other experimental details were reported previously (Ancheyta et al., 2001). Experiments were conducted at the following conditions pressure of 6.9, 8.3, and 9.8 MPa, temperature of 380°C-420°C, 5000 standard cubic feet per barrel of H2/oil ratio, and 1.5,0.5, and 0.33 h EHSV in the same isothermal bench-scale unit mentioned in the previous section. 

Marroquin, G., Ancheyta, J., Ramirez, A., Earfan, E. 2001. Effect of crude oil properties on the hydrodesulfurization of middle distillates over NiMo and CoMo catalysts. Energy Fuels 15 1213-1219. 

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