Simulated distillation, boiling point curves

Figure 3. Simulated distillation boiling point curves for virgin bitumen, mal-tenes, and asphaltenes...

Simulated Distillation Results. Important insight concerning the molecular-size distribution of asphaltenes vs. maltenes is gained by the simulated distillation data. The boiling point distribution curves are shown in Figure 3. These curves were drawn as follows. Quantitative simulated distillation data was obtained on the virgin bitumen and the maltenes. Direct information is obtained up to a nominal boiling point of 535°C shown by the vertical dashed line. The area under the curve for the nonvolatile portion is... 

Binary systems are known that form solid solutions over the entire range of composition and which exhibit either a maximum or a minimum in the melting point. The Uquidus-solidus curves have an appearance similar to that of the liquid-vapor curves in systems which f orm azeotropes. The mixture having the composition at the maximum or minimum of the curve melts sharply and simulates a pure substance in this respect just as an azeotrope boils at a definite temperature and distills unchanged. Mixtures having a maximum in the melting-point curve are comparatively rare. 

The physical and an tical data, i. e. melting point, MP, boiling point, BP, average relative particle weight, M, element analysis, and atomic ratio H/C are presented in Table 4-195. The simulated distillation curves (by TGA) are shown in Fig. 4-159. The asphaltenes do not contain any volatile components but do undergo a cracking reaction above 400 °C. The distillation (sublimation) curve of n-hexylpyrene is nearly 100°C-150 C below the corressponding curves of the other substances. 

For our convenience, we also add the D-86 stream correlations to every product stream from the column in Figure 2.46. We may also add other types of distillations (TB P, D2887) from the same menu. The simulator arranges the hypothetical and real components in order of increasing boiling point and generates a TBP curve from the cumulative composition and boibng data. Popular correlations... 

We enter the distillation curve as shown in Figure 2.59. We must enter at least 5 points that include both the initial boiling point and the final point. For this model, we always enter as a 9-point distillation curve. It is also important to make sure that we choose the correct distillation type. As we noted earlier, we corrected all data to follow a D-86 curve. It is possible to use a combination of a D-86, D-1160, SimDist and TBP distillation curves in the assay input. The choice of distillation plays an important role when we create a pseudocomponent list because simulation software converts all distillation curves into a TBP basis. 

Distillation simulated by gas chromatography is a reproducible method for analyzing a petroleum cut it is appiicabie for mixtures whose end point is less than 500°C and the boiling range is greater than 50°C. The results of this test are presented in the form of a curve showing temperature as a function of the weight per cent distilled equivalent to an atmospheric TBP. 

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