Subsea multiphase fluid separating system and method

A subsurface method for separation of multiphase production fluids from one or more wells drilled below a body of water, comprising:

• positioning separation equipment for said separation below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluids from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids from said one or more wells in the following sequence:
• separating a gas phase and a liquid phase of said multiphase production fluid from said one or more wells;
• subsequently preseparating said liquid phase of said multiphase production fluid;
• thereafter processing said liquid phase for separation of an oil phase and a water phase;
• and
• cleaning oily water of said water phase.

A subsurface method for separation of multiphase production fluids from one or more wells drilled below a body of water, comprising:

• positioning separation equipment for said separation below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluids from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids from said one or more wells in the following sequence:
• preseparating said multiphase production fluid to produce a preprocessed fluid;
• separating an oil phase and a water phase and any residual gas from said preprocessed fluid to produce an oil output an oily water output;
• and
• cleaning of said oily water output to produce a water output and residual oil.

A subsurface method for separation of multiphase production fluids from one or more wells drilled below a body of water, comprising:

• positioning separation equipment for said separation below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluids from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids from said one or more wells in the following sequence:
• separating an oil phase and a water phase and a gas phase from said multiphase production fluids;
• and
• cleaning of oily water from said water phase to produce a water output and residual oil.

A subsurface method for separation of multiphase production fluids from one or more wells drilled below a body of water, comprising:

• positioning separation equipment for said separation below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluids from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids from said one or more wells in the following sequence:
• separating of a gas phase and a liquid phase to produce a gas output and a processed fluid;
• separating an oil phase and water phase and any residual gas from said processed fluid to produce an oil output and a water output.

A subsurface method for separation of multiphase production fluids from one or more wells drilled below a body of water comprising:

• positioning separation equipment for said separation below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluid from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids from said one or more wells in the following s equence:
• separating solids from said multiphase production fluid of said one or more wells to produce solids and a processed fluid;
• and
• separating an oil phase and a water phase and any residual gas from said processed fluid to produce an oil output and a water output.

A subsurface method for separation of multiphase production fluids from one or more wells drilled below a body of water, comprising:

• positioning separation equipment for said separation below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluid from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids from said one or more wells in the following sequence:
• separating solids from said multiphase production fluid of said one or more wells to produce solids;
• and
• separating of a gas phase and a liquid phase to produce a gas output and a processed fluid.

A subsea system for separating a multiphase fluid from one or more subsea wells, comprising:

• a separator system frame for rigidly supporting said subsea system suitable for operation in a subsea environment;
• a first cyclone separator rigidly secured to said separator system frame and being operable for removing solids from said multiphase fluid, said first cyclone separator being adapted for connection with said one or more subsea wells for receiving said multiphase fluid;
• a gravity separator rigidly secured to said separator system frame;
• and
• a first fluid connection downstream from said cyclone separator to said gravity separator.

A subsea system for separating a multiphase fluid from one or more subsea wells, comprising:

• a separator system frame for rigidly supporting said subsea system suitable for operation in a subsea environment;
• at least two of the following five components rigidly secured to said separator system frame consisting of the following:
• a cyclone separator operable for removing solids from said multiphase fluid, a cyclone or augur separator operable for removing a gas phase from a liquid phase, a preseparator liquid-liquid hydrocyclone operable for enhancing separation of an oil phase and a water phase, a gravity separator operable for separating said oil phase and said water phase, and a deoiling liquid-liquid hydrocyclone operable for deoiling oily water;
• said at least two of the following five components being interconnected with each other such that when used each of said at least two of the following five components are arranged in the following order for processing said multiphase fluid:
• said cyclone separator, said cyclone or augur separator, said preseparator liquid-liquid hydrocyclone, said gravity separator, and said deoiling liquid-liquid hydrocyclone.

A subsea method for separation of multiphase production fluids from one or more wells drilled below a body of water, comprising:

• positioning separation equipment for separation of multiphase production fluids below a surface of said body of water and in proximity with said one or more wells;
• connecting said one or more wells to said separation equipment to introduce said multiphase production fluids from said one or more wells to said separation equipment;
• operating said separation equipment for separating phases of said multiphase production fluids such that at least two of the following five processes are provided:
• separating solids from said multiphase fluid, separating a gas phase and a liquid phase, liquid-liquid preseparating to enhance separation of an oil phase and a water phase, gravity separating said oil phase and said water phase, and cleaning oily water to produce water and residual oil;
• and
• each of said at two of the five processes when used being operated in the sequence of operation as follows:
• said step of separating solids from said multiphase fluid, said step of separating said gas phase and said liquid phase, said liquid-liquid preseparating, said step of gravity separating, and said step of cleaning oily water to produce water and residual oil.