Hydrogen consumption data

These caluclations of refinery hydrogen requirements are based on hydrogen consumption data summarized in Table 6 for the various processes that consume and produce hydrogen. These hydrogen consumption data allow for the theoretical hydrogen consumption and 20% excess above that required to maintain the desired hydrogen purity in the process. 

Ramachandran and Menon (1998) presented a brief review on the various uses of hydrogen in the industry. They pointed out that in modern refineries, hydrogen requirement is commonly about lwt% of the crude processed. Typical hydrogen consumption data for various refinery processes are presented in Table 12.9. Hydrocracking of vacuum distillates requires a large amount of hydrogen, not only for desulfurization but also for the increase in the hydrogen/carbon ratio of the products relative to the feed (Aitani, 1996). 

Typical Hydrogen Consumption Data for Various Refinery Processes... 

It is possible to produce some liquid hydrocarbons from most coals during conversion (pyrolysis and hydrogenation/ catalytic and via solvent refining)/ but the yield and hydrogen consumption required to achieve this yield can vary widely from coal to coal. The weight of data in the literature indicate that the liquid hydrocarbons are derived from the so-called reactive maceralS/ i.e. the vitrinites and exinites present (7 8 1 9). Thusf for coals of the same rank the yield of liquids during conversion would be expected to vary with the vitrinite plus exinite contents. This leads to the general question of effect of rank on the response of a vitrinite and on the yield of liquid products and/ in the context of Australian bituminous coals, where semi-fusinite is usually abundant/ of the role of this maceral in conversion. 

Clearly, a comprehensive description of catalytic systems is not possible from the hydrogen consumption alone. The reaction sequence represented in Scheme 10.3 already contains 16 rate constants. However, valuable data regarding the catalysis can be obtained from an analysis of the gross hydrogen consumption on the basis of Eq. (13), for various catalytic systems. Some practical examples of this are described in the following section. 

The experimental data analysis shows, that the hydrogen consumption in the Ni-B alloy is lower, than in the Ni coating at the same electrolysis regimes. So, when ik = 4 A/dm2 for Ni film Vh2 — 85 cm3/ 100 g, and for Ni-B - Vh2 — 65 cm3/ 100 g, that is 1,3 times smaller. This phenomenon can be explained by the particularities of the Ni-B alloy formation mechanism. When ik achieves the value higher, than... 

The first run with ICR 106 catalyst (Run 81-4) was a 2000-hr test made in a relatively small pilot plant containing 130 mL of catalyst to determine denitrification kinetics and hydrogen consumption. Activity data are plotted in Figure 1 for 0.2, 0.3, and 0.6 LHSV. A simple first-... 

The relative change in SRC conversion vs. hydrogen consumption is seen in Figure 3 for both 750° and 850°F cut point data. As hydrogen consumption increases, SRC conversion also increases. The intercept for the 750°F cut point data suggests that 0.8 wt % hydrogen addition to the feed is necessary before any conversion of the residue is observed. This type of result also has been observed in our studies on synthetic filtrate. 

Because we find that a linear relationship exists between temperature and hydrogen consumption on the one hand and between temperature and SRC conversion on the other, a linear relation should exist between hydrogen consumption and SRC conversion. Indeed, the plot of data in Figure 10 shows such a relationship. 

A comparison of 850°F+ SRC conversion vs. hydrogen consumption is shown in Figure 10. The efficiency of hydrogen utilization is extremely important in this process where hydrogen costs will be so great. These data show no significant difference in conversion vs. hydrogen consumption. 

This is a multiple input and output problem where there are 20 input and 5 output nodes. The simulated results of the product slate covering hydrogen consumption, naphtha, light kerosene, light diesel, fractionator bottoms and 975°F+ conversion are given in Table 2. The AAD% s for the five set of test run data used to train the model are ranging between 0.292 to 0.56 % which results the mean AAD% less than 0.5 %. The maximum ARD% which appears in the light diesel of the fourth test run data set, is 1.843 %. The reliability of this model is clearly shown. 

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