Gas absorption equipment

Fixed-bed reactors in the form of gas absorption equipment are used commonly for noncatalytic gas-liquid reactions. Here the packed bed serves only to give good contact between the gas and liquid. Both cocurrent and countercurrent operations are used. Countercurrent operation gives the highest reaction rates. Cocurrent operation is preferred if a short liquid residence time is required. 

Equipment The principal types of gas-absorption equipment may be classified as follows ... 

Of the three categories, the packed column is by far the most commonly used for the absorption of gaseous pollutants. Miscellaneous gas-absorption equipment could include acid gas scrubbers that are commonly classified as either wet or diy. In wet scrubber systems, the absorption tower uses a hme-based sorbent liquor that reacts with the acid gases to form a wet/solid by-product. Diy scrubbers can be grouped into three catagories (1) spray diyers (2) circulating spray diyers and (3) dry injection. Each of these systems yields a diy product that can be captured with a fabric filter baghouse downstream and... 

Adsorption The design of gas-adsorption equipment is in many ways analogous to the design of gas-absorption equipment, with a solid adsorbent replacing the liqiiid solvent (see Secs. 16 and 19). Similarity is evident in the material- and energy-balance equations as well as in the methods employed to determine the column height. The final choice, as one would expect, rests with the overall process economics. 

The fourth example, the use of chemical processing on Mars for producing a propellant, is presented in Section 1.9.7 [106]. The fifth and last example describes the use of distributed systems for global carbon dioxide management, aiming at reducing the greenhouse effect [106]. The main issue here is the installation of gas-absorption equipment for CO2 capture at central, fossil-fuel power plants. 

Measurement of the kinetics of gas-liquid reactions is of great importance in the design of gas absorption equipment. The jet reactor provides a means of determining solubilities and reaction rates for gases which react rapidly with the liquid. A narrow jet of the liquid is passed through a reactive gas into a receiver, from which samples are taken to determine the amount of absorption, Fig. 5.23. 

Free-surface flow with interfacial transport processes is a subject of great interest since its effects can be seen both in nature and practical devices, such as the air-sea interface, ship wakes, and chemical processes like gas-absorption equipment. In many cases, it is necessary to investigate the interaction of the flow and the free surface or correlate the free-surface deformation with the flow characteristics beneath the liquid surface. To this end, PIV technique can be applied to some free-surface flows as a powerful experimental tool. 

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