Abstract: A vapor recovery system is provided which includes a vapor recovery cycle and a regeneration cycle. The vapor recovery is condensation of the vapors in an air-vapor mixture utilizing a chiller cooled by a refrigerant gas to condense and remove vapor and to vent the air. The refrigerant cooling is provided by a compression-condensation-expansion refrigeration cycle. During the vapor recovery cycle ice tends to build up in the chiller due to the small amounts of water contained in the air-vapor mixture. In the regeneration cycle the hot refrigerant gas from the compressor by-passes the condenser and expansion valve to heat the "chiller", which heats the air-vapor mixture and melts any accumulated ice. During the regeneration cycle there is no venting and the entire air-vapor mixture is recycled to the chiller until the regeneration is completed. In addition to heating and meting ice in the system, the heated air-vapor mixture may be used to dry and regenerate desiccant material in the system.

Abstract: An integrated vapor recovery system is provided in which the absorption oil used is withdrawn from the tank saturated with the vapors. The absorption oil is then chilled to about 35.degree. to 40 .degree. F. to produce a lean oil for the absorption column. The absorption column is operated at substantially or below atmospheric pressure, such that the vapors are recovered substantially by absorption alone with very little condensation. The lower pressures also reduce the likelihoods of explosive mixtures.

Abstract: A vapor recovery system is disclosed wherein the condensable organic compounds e.g., hydrocarbons or chemicals contained in hydrated air mixture are removed by first dehydrating the vapors by refrigeration then desiccation followed by indirect heat exchange with a refrigerant gas at cryogenic temperatures in a chiller. The clean vapors from the system may be used to pre-cool the air mixture prior to contact in the chiller. Additionally, the clean, dry vapors may be used to regenerate the desiccant within the dehydrator. The rehydrated clean vapors may be dehydrated by returning them to the feed to the system.

Abstract: The present invention utilizes a turboexpander coupled with a compressor in place of the Joules-Thomson expansion valve in a conventional refrigeration to achieve higher efficiency. More specifically the refrigeration is used in removing condensable hydrocarbons or chemical vapors from air which has been contaminated during loading and unloading at bulk plants. The more efficient turboexpansion cycle allows the use of saturated lower aliphatic hydrocarbons, such as ethane as refrigerant, the use of which would be precluded from normal Joules-Thomson expansion cycles. The turboexpander work is used to drive a compressor which partially recompresses the expanded refrigerant gas, providing an essentially isentropic expansion. Because the turboexpander and the compressor operate on the same fluid, the mass flows through both are equal thereby alleviating control and loading problems.