Hypersorption process

Most adsorption systems use stationary-bed adsorbers. However, efforts have been made over the years to develop moving-bed adsorption processes in which the adsorbent is moved from an adsorption chamber to another chamber for regeneration, with countercurrent contacting of gases with the adsorbents in each chamber. Union Oil s Hypersorption Process (90) is an example. However, this process proved uneconomical, primarily because of excessive losses resulting from adsorbent attrition. 

The third and final step in both cases consisted of operating the column or tower continuously with a constant feed and constant draw-off of products. In distillation this step is represented by the large continuous fractionating columns now used in many petroleum and chemical plants. In adsorption it is represented by the Hypersorption process (8, 4, 28, 29). 

Perhaps the hypersorption process (7) of recent years may be thought new and it is new in applying the mechanical principle of continuous operation to charcoal adsorption, but such adsorption on a batch process was in use more than 25 years ago and became obsolete in competition with absorption. Now the continuous hypersorption method appears to be finding a real field of usefulness, especially in making very high recoveries of propane and in recovering substantial amounts of ethane. Recovery of ethane is beginning to be important, in connection with its use as a chemical raw material for the reactions mentioned previously in this paper. 

HYPERSORPTION. Process in w-hiclt activated car lion selectively absorbs the less-volatile components from a gaseous mix. while the more-volatile components pass on unaffected. Particularly applicable to separations of low-boiling mixtures such as hydrogen and methane, ethane from natural gas, ethylene from refinery gas, etc. 

Studies have been made of continuous systems. In the hypersorption process, a vertical column contains a bed of carbon that continuously moves downward. Raw gas enters at a point midway in the column. As the smaller hydrocarbon molecules are less adsorbable they flow upward to be collected and recovered at the top of the column whereas the larger hydrocarbon molecules are adsorbed and are carried with the carbon to the discharge at the bottom. The adsorbed hydrocarbons are recovered at a heating station and the denuded carbon is returned to the top of the column to repeat the cycle.25... 

If several adsorbate components are adsorbed to a different extent by the adsorbent, counterflow fractioning is required for the separation. For example, in a rectisorption or hypersorption process (Fig. 4-18), a gas... 

FIGURE 12.7. Schematic diagram of hypersorption process showing test mass balance, temperatures, and other operating data. 

Many industrial countercurrent fractionation processes for the separation of components operate on the principle of either the three and four section cascade or the simulated moving bed. A summary of simulated moving bed and countercurrent fractionation processes is given in Table S.l. With the exception of the Hypersorption process all are presently operated commercially. 

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