This paper evaluates a technical new approach to establish the optimum operating conditions of associated gas multistage compression systems. The target is to maximize the total steady-state hydrocarbon (HC) liquids recovery of the surface producing facilities utilizing available resources and without any the need for plant modification. Maximizing liquids removal from associated gas has several benefits to gas-oil separation plants (GOSPs) such as increasing crude oil throughput, exporting leaner gas through pipelines in addition to other advantages that will be highlighted through two implemented case studies: 1. Abu Ali Plant (Arab Extra Light crude oil producing facility). 2. Manifa Central Processing facility (Arab Heavy crude oil producing facility). The concept is basically to raise the after-cooler's operating temperature (minimize cooling) of the lower pressure compression stages, to enable shifting rich/heavier gas to the optimum side where it is more favorable for the HC heavy ends to coalesce and condense. At that point, the after-cooling is maximized to collect the liquids from the discharge knockout (KO) drum of the highest pressure compression stage. This setup, when compared to conventional setup, which is maximizing the cooling across all stages, yields higher overall HC liquid recovery from the associated gas. In case study #1, where condensate removed from the gas compression plant is normally spiked in the crude production, this approach was evaluated and field tested, resulting in gain of 2,000 barrels per day in export crude for the same GOSP feed rate. In addition, 50% drop in export gas water load and 25% drop in the HC's dew point was achieved, which helps mitigating pipeline corrosion and slugging issues in export gas transport, given the unavailability of a gas conditioning system in the facility. In case study #2, where condensate removed from the gas compression plant is segregated and shipped to downstream facilities, this approach was evaluated, field tested and resulted in a gain of approximately 5,000 barrels per day in export condensates for the same GOSP feed rate. This gain resolved a chronic low velocity issue in the export condensate pipeline and helped mitigate water, solids settling and associated corrosion problems in the pipeline as well as downstream facilities upsets.
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