Hypersorption

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. 

FIG, 16-52 Hypersorption adsorber vessel [Reptinted with permission of AIChE. Reference Berg, Chem. Eng. Progr., 47, 585 590 (1951).]... 

Hypersorption A continuous chromatographic separation process using a moving bed. Invented in 1919 by F. D. Soddy (famed for his work on isotopes) at Oxford and developed commercially for petroleum refinery separations by the Union Oil Company of California in 1946. Six plants were built in the late 1940s, using activated carbon as the adsorbent. The process was abandoned because attrition of the bed particles proved uneconomic. 

Today s petroleum distillation plants are compared with the units in existence in 1925, and a review is presented of the advances during the past 25 years in construction practices and materials, instrumentation, and engineering design, which have made possible the current technology. The theory and application of special processes, such as azeotropic and extractive distillation and Hypersorption, are discussed. The development of molecular distillation and rotary columns is described to indicate possible trends to be expected in the future. 

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. 

Hypersorption. The apphcations of Hypersorption in modern gas processing plants have been outlined by Berg (4). The recovery of ethylene from refinery gas streams is discussed, and analyses of process streams are presented. 

Section, which appears every month. It also has a special section on Patents which lists new patents according to their classification. The Process Issue of the Petroleum Refiner is now carrying a special section on Petrochemical Processes. In the September 1952 issue for example, Extractive Distillation for Aromatic Recovery, Modified SO2 Extraction for Aromatic Recovery, Udex Extraction, Ethylene Manufacture by Cracking, Ethylene Production, Hypersorption, Hydrocol, Dehydrogenation (for butadiene), and Butadiene Process, were described. These descriptions include the main essentials of the process, simplified flow diagrams, and the name of the company offering it. Formerly these processes were described under the Process Section. 

C. Bei g, Recent Trends in Refining Processing. Hypersorption in Modem Gas Processing Plants,... 

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... 

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