Absorption design

To decide the most economic water flow-rate, the stripper design should be considered together with the absorption design, but for the purpose of this example the absorption design will be considered alone. Using Figure 11.40 the number of stages required at different water rates will be determined and the optimum rate chosen ... 

Scaling Up from Laboratory Data Laboratory experimental techniques offer an efficient and cost-effective route to develop commercial absorption designs. For example, Ouwerkerk (Hydrocarbon Process., April 1978, 89-94) revealed that both laboratory and small-scale pilot plant data were employed as the basis for the design of an 8.5-m (28-ft) diameter commercial Shell Claus off-gas treating (SCOT) tray-type absorber. Ouwerkerk claimed that the cost of developing comprehensive design procedures can be minimized, especially in the development of a new process, by the use of these modern techniques. 

The gas flows horizontally, contacting by downflowing liquid. The effective driving force for mass transfer is between that for counter- and cocurrent contactors. Crossflow scrubbers have low pressure drop and usually require a lower liquid/gas ratio than either counter- or cocurrent scrubbers. The time of contact between gas and liquid is relatively low, and crossflow units are not reconunended for most chemical absorptions. Design procedures follow a finite-element approach the scrubber volume is divided into cubes, each of which is assumed to reach equilibrium. 

Countercurrent Phase Flow Absorption, Design of Countercurrent Flow Columns... 

The term spedation will be defined here both in an operational and in a more descriptive way (Bernhard et al. 1986). Operational means the use of appropriate analytical separation and detection methods (e.g. filtration, chemical leaching and extraction, chromatographic fractionation, atomic absorption) designed to simulate conditions, which may favor the "extractability" of a particular metal form, association, or binding substrate. 

A main advantage of the virial equation, as compared to the other EoS, is that there is an exact relationship between B mixture) and the B values of the mixture components and their pairs, as we will see in Chapter 11. It finds, thus, extensive application in the description of the vapor phase nonideality in distillation or gas absorption design up to moderate pressures. 

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