Petroleum fuels ultimate analyses

The computation of maximum volatile nitrogen yield was based upon the ultimate analysis of the chars generated at all drop tube furnace temperatures from 1000 C to 1700 C. Petroleum coke can have significant concentrations of fuel nitrogen measured in g/GJ (lb/10 Btu) as shown in Table 2.3. Further, this nitrogen can be concentrated more heavily in the char than the nitrogen in coal. 

Typically, petroleum residue is characterized by proximate analysis, which only quantifies the fraction of fuel material (FM), ash and moisture, and elemental (ultimate) analysis (C, H, O, N, S). In the proximate analysis, the fuel fraction is usually divided into two parts fixed carbon (FC) and volatile material (VM). For calculation purposes, both fractions are totalized as ash-free dry fuel matter (expressed in weight%). With the elemental analysis (reported in weight% dry basis for each element), it is possible to obtain the condensed formula of the fuel fraction and thus its molecular weight. 

Fuel oil, therefore, in its various categories has an extensive range of applications, and the choice of a standard procedure to be used for assessing or controlling product quality must, of necessity, depend on both the type of fuel and its ultimate use. But first, as for all petroleum analysis and testing, the importance of correct sampling of the fuel oil cannot be overemphasized, because no proper assessment of quality can be made unless the data are obtained on truly representative samples (ASTM D-270, IP 51). 

As regulations regarding the environmental impact of petroleum products like fuels and lubricants become more and more strict, the need for accurate and fast chemical analysis increases. Moreover, accurate and fast chemical analysis also strongly supports the production and ultimately the quality of the end product. The demand to reduce the concentrations of possibly harmfiil elements like sulfur imposes new challenges for detection technology. 

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