There is disclosed a waste treatment process for a fossil-fuel extraction site (18, 40), comprising: processing extracted waste generated by a fossil-fuel extraction process to produce primary waste having a higher calorific value than the extracted waste; mixing the primary waste with secondary waste to generate pyrolysis feedstock, the secondary waste having a lower calorific value than the primary waste; pyrolysing the pyrolysis feedstock in a pyrolysis unit (32) to form pyrolysis char; and gasifying the pyrolysis char in a gasification unit (36) to form syngas and ash.

A subsea fluids storage facility comprises a tank (11) for holding and separating fluids which is equipped with ballast capacity (14) and a separable base (12) to be deployed upon the seabed in shallow or deep water, and the storage facility is connectable to a surface production facility, especially a buoy (24) for processing fluids. In deep water the tank (11) is held at a depth above the base (12) for temperature controlled stabilization of produced oil in the tank (11).

A subsea fluids storage facility comprises a tank (11) for holding and separating fluids which is equipped with ballast capacity (14) and a separable base (12) to be deployed upon the seabed in shallow or deep water, and the storage facility is connectable to a surface production facility, especially a buoy (24) for processing fluids. In deep water the tank (11) is held at a depth above the base (12) for temperature controlled stabilization of produced oil in the tank (11).

A subsea drilling method and system controls drilling fluid pressure in the borehole of a subsea well, and separates gas from the drilling fluid. Drilling fluid is pumped into the borehole through a drill string and returned through an annulus between the drill string and the well bore and between the drill string and a riser. Drilling fluid pressure is controlled by draining fluid out of the riser or a BOP at a level between the seabed and the surface in order to adjust the hydrostatic head of drilling fluid in the riser. The drained drilling fluid and gas is separated in a subsea separator, where the gas is vented to the surface through a vent line, and the fluid is pumped to the surface via a subsea pump. A closing device and a choke line and valve can release pressure after a gas kick in the well.

A subsea drilling method and system controls drilling fluid pressure in the borehole of a subsea well, and separates gas from the drilling fluid. Drilling fluid is pumped into the borehole through a drill string and returned through an annulus between the drill string and the well bore and between the drill string and a riser. Drilling fluid pressure is controlled by draining fluid out of the riser or a BOP at a level between the seabed and the surface in order to adjust the hydrostatic head of drilling fluid in the riser. The drained drilling fluid and gas is separated in a subsea separator, where the gas is vented to the surface through a vent line, and the fluid is pumped to the surface via a subsea pump. A closing device and a choke line and valve can release pressure after a gas kick in the well.

A system includes a fluid injection system. The fluid injection system includes a rotary isobaric pressure exchanger (IPX) configured to receive a first fluid, to receive a second fluid extracted from a source well, to utilize the second fluid to pressurize the first fluid for injection into an injection well, and to inject the pressurized first fluid into the injection well.

A method and apparatus are disclosed for separating a multiphase fluid stream that includes a heavier fluid component and a lighter fluid component. The fluid flows along a first helical flowpath with a first pitch. The first helical flowpath is sufficiently long to establish a stabilised rotating fluid flow pattern for the stream. The uniform rotating fluid also flows along a second helical flowpath, the second helical flowpath having a second pitch greater than the first pitch. The lighter fluid is removed from a radially inner region of the second helical flowpath. The method and apparatus are particularly suitable for the separation of oil droplets from water, especially from water for reinjection into a subterranean formation as part of an oil and gas production operation. The method and apparatus are conveniently applied on a modular basis.

An asphaltenes separation system comprising a flocculant feed system configured to add a flocculant to a production fluid to flocculate asphaltenes in the production fluid, and an asphaltenes separator configured to remove flocculated asphaltenes from the production fluid.

An asphaltenes separation system comprising a flocculant feed system configured to add a flocculant to a production fluid to flocculate asphaltenes in the production fluid, and an asphaltenes separator configured to remove flocculated asphaltenes from the production fluid.

A drilling conductor supported within a suction anchor is installed by lowering the suction anchor through the top of a frame of a subsea processing unit. The base of the frame defines a landing area for the suction anchor and supports a fixing system for fixing the suction anchor to the frame. When the suction anchor has been embedded into the seabed beneath the processing unit, the frame is fixed to the suction anchor to form a structural unit that includes the conductor, the suction anchor and the frame. Additional equipment such as a blow-out presenter or a Christmas tree is lowered through the top of the frame and onto the conductor that is supported by the embedded suction anchor.