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There are many factors that influence the performance of a short-cycle unit. First and foremost, the separator ahead of the unit must remove all liquids and solids in the gas. A slug of liquid into the bed would damage the adsorbent and perhaps necessitate a changeout. The adsorption temperature should be as low as possible without causing hydrates ahead of the unit, to adsorb more of the heavier hydrocarbons. Proper regeneration of the bed is very important. A portion of the process stream is used for this purpose. Regeneration gas temperatures are in the order of 480 to 530°F. The tower should be heated to an outlet gas temperature of 390°F. While adsorbing and desorbing are important, the adequate condensing of the desorbed hydrocarbons is also very important. If the condensing is inefficient, the heavier hydrocarbons have no means of exiting from the gas stream. In warm climates, this is a major problem, requiring that the condenser be conservatively sized. Upon condensing, the liquids must be separated from the lighter hydrocarbons in the regeneration stream. Conservatively-sized vertical separators are usually used in this service. The design of the short-cycle dry desiccant units is usually performed by the seller of the desiccant. The seller develops the computer software and tests the simulation results in actual applications. Thus, the design results from the vendor are quite reliable.