System and method for compressing and conditioning hydrocarbon gas

Abstract

A system and method captures and processes flare gas so that the gas is usable as compressed natural gas (“CNG”). The flare gas is pressurized by a combination of a booster compressor and a CNG compressor. While interstage and between the booster compressor and the CNG compressor, the gas is treated to remove moisture and to separate out higher molecular weight hydrocarbons. The moisture is removed by contacting the interstage gas with a hygroscopic agent within a dehydration unit. The moisture free hydrocarbon fluid is expanded, and/or externally cooled and directed to a knock out drum. Higher molecular weight hydrocarbons are separated from the fluid in the knock out drum. Gas from the knock out drum is compressed in the CNG compressor.

Dependencies are inferred from the claim text.