Watson factor

This factor is the intermediate parameter employed in numerous calculational methods. For petroleum cuts obtained by distillation from the same crude oil, the Watson factor is generally constant when the boiling points are above 200°C. 

These equations differ from those of [4.20] in that the Watson factor is taken into account. 

This relation should not be applied for temperatures less than 0°C. Its average accuracy is on the order of 5%. For a Watson factor ot 11.8, the C j can be obtained from the curve shown in Figure 4.4. For different K, values, the following correction is used (... 

In order to increase the level of confidence, a number of other statistics in addition to xi should be calculated. These include the standard deviation of the wetted residuals, the mean residual, a skewness of fit parameter, and, especially, the Durbin-Watson factor, DB By using DB, calculated according to (57)... 

Joint design - cylindrical joints C WATSON Factors affecting joint performance specimen calculation... 

Using the 50% point of the TBP, estimate the Watson factor (K ). Set the 50% TBP temperature as an initial guess for the mean-average boiling point (MeABP) (see also Section 1.5). 

If the boiling temperature is not known, it is somewhat risky to estimate it. One could, if the Watson characterization factor is known, use the following... 

Watson characterization factor log = common logarithm (base 10)... 

K y = Watson characterization factor 5 = standard specific gravity... 

Watson characterization factor Tu = normal boiling point... 

The Watson characterization factor has also been used as a measure of the chemical character of a cmde oil or its fractions ... 

When a single technique is employed only local life-cycle cost minimization is achieved. If the global life-cycle cost is to be minimized, a number of techniques have to be applied (Watson et al., 1996). In this case, tools and techniques shouldn t compete with each other, but be complementary in the product development process. The correct positioning of the various off-line tools and techniques in the product development process, therefore, becomes an important consideration in their effective usage. Patterns of application have been proposed by a number of workers over several years (Brown et al., 1989 Jakobsen, 1993 Norell, 1993) and the importance of concurrency has been highlighted as a critical factor in their use (Poolton and Barclay, 1996). 

Another relationship used to indicate the crude type is the Watson characterization factor. The factor also relates the mid-boiling point of the crude or a fraction to the specific gravity. 

The UOP method uses CABP which, for all practical purposes, is the same as VABP as shown in Appendix 2. The factor is more popular than because the VABP data are readily available. The use of MeABP in the Watson method generally results in a lower K value than that of UOP. Example 2-1 illustrates steps to calculate the and factors. 

Hydrocariion Liquid Enthalpies at Various Watson K Factors... 

Figure 5-7. Hydrocarbon liquid enthalpies at various Watson K factors.

In other instances, reaction kinetic data provide an insight into the rate-controlling steps but not the reaction mechanism see, for example, Hougen and Watson s analysis of the kinetics of the hydrogenation of mixed isooctenes (16). Analysis of kinetic data can, however, yield a convenient analytical insight into the relative catalyst activities, and the effects of such factors as catalyst age, temperature, and feed-gas impurities on the catalyst. 

Many theoretical embellishments have been made to the basic model of pore diffusion as presented here. Effectiveness factors have been derived for reaction orders other than first and for Hougen and Watson kinetics. These require a numerical solution of Equation (10.3). Shape and tortuosity factors have been introduced to treat pores that have geometries other than the idealized cylinders considered here. The Knudsen diffusivity or a combination of Knudsen and bulk diffusivities has been used for very small pores. While these studies have theoretical importance and may help explain some observations, they are not yet developed well enough for predictive use. Our knowledge of the internal structure of a porous catalyst is still rather rudimentary and imposes a basic limitation on theoretical predictions. We will give a brief account of Knudsen diffusion. 

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