FIELD: oil, gas and coke-chemical industries.
SUBSTANCE: group of inventions relates to methods for field preparation of hydrocarbon gases and can be used in oil industry for processing associated petroleum gas. Proposed are four embodiments of the plant, comprising two compressor stations, a recuperative heat exchanger, two separators, three-phase separator, gas drying and/or cleaning unit, dephlegmator with external cold source, as well as reducing devices. In embodiments 3 and 4, the upper part of the dephlegmator is equipped with a heat-mass exchange section. During operation of first embodiment of associated oil gas of first stages of separation is mixed with stabilization gas, compressed in first compressor, is mixed with separation gas from three-phase separator, cooled in heat exchanger and separated in the first separator into residue and gas, which is dried and/or purified and supplied to the bottom of the dephlegmator, the upper end of which is cooled with a cooling agent supplied from the cold source. Reflux gas is withdrawn from the top of the dephlegmator, heated in a heat exchanger and discharged as a dry stripped gas, and reflux is discharged from the bottom of the dephlegmator. Associated oil gas of end separation plant is compressed in second compressor and separated in second separator into gas and residue. Separation residue and reflux are reduced, mixed and directed to three-phase separator, from which water condensate, NGF and stabilization gas are removed. Operation of the second and fourth embodiments of the plant are characterized by recuperative cooling in the heat exchanger of separation gas after the drying and/or cleaning unit. Operation of the third and fourth embodiments of the plant is characterized by additional recuperative cooling of the refluxer top part by means of a heat-mass exchange section.
EFFECT: group of inventions provides reduced metal consumption and reduced power consumption.
4 cl, 4 dwg
