DEEPWATER PRODUCTION SYSTEM Russian patent published in 2018 - IPC E21B43/01 E21B43/36 

FIELD: oil industry.

SUBSTANCE: invention relates to a system for oil production in remote deep-water areas where conditions may require closing and removal of surface facilities and equipment. Method comprises producing hydrocarbons from one of more subsea wells (36) and introducing the produced hydrocarbons into one or more separation tanks (12) in subsea oil production unit (DPS) (10) resting at the sea bed. Allowing the produced hydrocarbons to separate from associated gas and water in one or more tanks (12) to give a gas phase, an oil phase and a produced water phase. Conducting at least a part of the produced water separated from the oil in DPS (10) to subsea injection well(s) (37) through injection pump (22). Providing a temporary fluid connection between separation tank(s) (12) and production and transport vessel (1) for transporting separated oil from separation tank(s) (12) to vessel (1) and gas and water from vessel (1). Conducting separated oil from storage and separation tank(s) (12) to the vessel. Separating the stream of hydrocarbons into stabilised oil, gas and water in separation system (40) onboard vessel (1). Introducing the separated oil into storage tank(s) (41) onboard the vessel. Returning separated gas and water to DPS (10). Injecting the returned water and/or gas into water and/or gas injection wells (35, 37), respectively, and disconnecting vessel (1) from the fluid contact if disconnection is required. Method further comprises continuing hydrocarbon production from subsea well(s) (36) when DPS (10) and vessel (1) are disconnected until separation tank(s) (12) and/or produced oil storage tank(s) are filled with produced oil. At least a part of the gas returned from vessel(1) to DPS (10) is temporarily stored in separation and storage tank (12) at the top of the oil, or in separate gas tank (2) in DPS (10) before being injected into the gas injection well(s).

EFFECT: technical result is an increase in the efficiency and continuity of oil production.

9 cl, 3 dwg