Exhausting section

Casings. Nozzles D Max. Press. Inlet Section Dsia. Exhaust Section Dsio. Other DSiO... 

Airflow created in the vicinity of local and general exhausts (Section 7.6) ... 

Previous data have concerned rmconfined flame configurations driven by velocity perturbations. These cases are less dependent on the geometry because sound generation is not modified by reflection from boundaries. It is also easier to examine rmconfined flames with optical techniques. However, in many applications, combustion takes place in confined environments and sound radiation takes place from the combustor inlet or exhaust sections. The presence of bormdaries has two main effects ... 

Polycyclic aromatic hydrocarbons (PAHs), constituents of cigarette smoke and diesel exhaust (Section 17.5) Examples of common dmgs that contain an aromatic ring—Zoloft, Valium, Novocain, Viracept, Viagra, and Claritin (Section 17.5)... 

As the other key molecule for reduction NO has been chosen. Environmental constraints require its removal in automotive exhaust (Section 5.3) as well as for stack gas (Section 5.4). In the latter case ammonia as reductant is to be chosen, because of the high oxygen concentration in stack gas. 

In addition, video cameras are positioned on the furnace side, and above the furnace horizontal exhaust section. Image processing is performed on raw video camera data to analyze and quantify flame shape and luminosity. Finally, an electric damper in the chinmey duct controls the furnace pressure to simulate various air-in leakage conditions. 

The point of intersection of the two operating lines will help locate the exhausting-section operating line. This can be established as follows. Subtracting equation (6-20) from (6-15) gives... 

Figure 12.25. Enricher and exhauster sections, (a) Enricher. (t>) Exhauster.

Effective absorption and stripping factors for each component are computed for the enricher and exhauster sections from (12-101) and (12-102) for terminal-stage conditions based on the above calculations. 

FIGURE 8.2 The picture of MTZ motion across the adsorption bed. (a through d) The steps of the MTZ motion across the adsorption bed (black—completely exhausted section, white—section with fresh adsorbent). 

Although not used in this book, other texts refer to the section of the column above the feed tray as the rectifying or the enriching section. In this section the vapour flow is greater than the liquid flow. The lower section is referred to as the stripping or exhausting section. Here the vapour flow is smaller than the liquid flow. 

The feed F splits the column into two sections. The accepted conventions dictate that we refer to the light species and, therefore, that the upper section be called the enriching section and the lower section be called the stripping (exhausting) section. 

Consider a domain encapsulating the bottom of the column and a few plates from the exhausting section. Write that the input is equal to the output ... 

The feed to be fractionated, which can be a liquid, a vapor, or even a combination of both, enters the column at some central location rather tiian at one of the ends of the cascade as had previously been the case. This results in a division of the column into two parts, the rectification or enriching section above the feed tray, and the stripping or exhausting section below it. The upper section serves to enrich the vapor in the more volatile components, a portion of which is ultimately withdrawn as liquid "overhead product" or "distillate." In the lower section, residual volatile components are progressively stripped off the liquid and conveyed upward as vapor, while the downward flow of liquid becomes enriched in fhe heavier or less-volatile components. 

Exhausting Section Reboiled Vapor in Equilibrium with Residue... 

These provide the equation of the exhausting-section operating line,... 

It is convenient before proceeding further to establish how the introduction of the feed influences the change in slope of the operating lines as we pass from the enriching to the exhausting sections of the fractionator. 

The diameter of the tower and the tray design are established through the methods of Chap. 6. Note the substantially different liquid loads in the enriching and exhausting sections. A colunm of constant diameter for all sections is usually desired for simplicity in construction and lower cost. If the discrepancy between liquid or vapor quantities in the two sections is considerable, however, and particularly if expensive alloy or nonferrous metal is used, different diameters for the two sections may be warranted. 

The A-rich layer from the decanter (Fig. 9,47) is sent to the top tray of fractionator II, which contains only a stripping or exhausting section. It is clear from Fig. 9.46 that the residue product composition x can be as nearly pure A as desired (turn the figure upside down to give it its usual appearance). The overhead vapor from tower-II wil be of composition which, when totally condensed as mixture N, produces the same two insoluble liquids as the first distillate. Consequently a common condenser can be used for both towers. 

In practice it will be desirable to cool the distillate below its bubble point to prevent excessive loss of vapor from the vent of the decanter. This changes the compositions j and slightly and provides somewhat larger internal reflux ratios. If the feed itself consists of two insoluble liquids, it can be fed to the decanter, whereupon both fractionators then consist of exhausting sections only. When it is desired to remove the last traces of water from a substance such as a hydrocarbon, it is common practice to use only one tower from which the dry hydrocarbon is removed as the residue product. The hydrocarbon-rich layer from the decanter is returned as reflux, but the water layer, which contains very little hydrocarbon, is normally discarded. 

As an alternative to these methods, calculations can be made analytically using the Kremser equations (5.50) to (5.57) or Fig. 5.16, since even for systems where the McCabe-Thiele assumptions are not generally applicable, the operating lines are straight at the extreme concentrations now under consideration. The exhausting section is considered as a stripper for the more volatile component, whence, for a kettle-type reboiler. 

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