| 摘要 |
<p>A vapor recovery unit (10, 30) comprising a vapor inlet for taking up hydrocarbon vapor/carrier gas mixture from a loading facility or the like, and thereafter alternately allowing the vapor to flow to one of at least two adsorber vessels (12, 14). Each adsorber vessel includes an entry port in the bottom of the adsorber vessel for receiving vapor. Hydrocarbons are retained on activated carbon beds in the adsorber vessels (12, 14), resulting in purified air or other carrier gas which is removed through a discharge port also in the bottom of each adsorber vessel (12, 14) and released through an elevated vent to the atmosphere. Hydrocarbon vapor is desorbed from the adsorber vessel (12, 14) by a vacuum system (30) and directed to a separator/absorber (34, 36) vessel wherein the desorbed vapor which has passed through the vacuum system is brought into contact with a hydrocarbon absorbent liquid or condenser. In use, when one adsorber vessel (34 or 36) is taking in vapor from the vapor inlet, the other adsorber vessel is having its adsorbent bed desorbed or regenerated. When the adsorbent bed is saturated, or if desired on a time cycle, the process will alternate. The adsorber vessels of the present invention do not require any flow lines or vent lines on the top of the adsorber vessels thereby allowing for easier maintenance and installation of the adsorber vessels. The entire system is designed to be fitted to and located on a skid or skids. <IMAGE></p> |
