A shut-off device for a pipe in a pipeline and responsive to ingress of water, has at least two valves for installation in the pipe of the pipeline. Each valve has a valve member supported for movement between an open position when the valve is open for passage of a fluid through the pipe, and a closed position when the valve is closed for preventing passage of the fluid through the valve. The device includes a buoyant member associated with the valve members for causing movement of the valve members to the closed positions upon ingress of water to the buoyant member. The valve members are moved to the closed positions in respective upstream and downstream directions of passage of the fluid through the pipe.

A gas export assembly is provided including a gas production facility adapted to generate pressurized gas for export to a remote facility through a pipeline; a determining an upper humidity threshold for the export gas in the pipeline; a determining, on the basis of the upper humidity threshold, a pipeline inlet humidity for the export gas, which pipeline inlet humidity is lower than the upper humidity threshold; and a regulator stage adapted to adjust the humidity of the export gas to the pipeline inlet humidity.

A system and method for accessing a gas main is provided. The system including a drip riser having an interior portion and a first quick-connect coupler, the first quick-connect coupler being fluidly coupled to the interior portion. A riser attachment device is provided having a second quick-connect coupler, an open end, and a valve disposed between the second quick-connect coupler and the open end. The second quick-connect coupler is configured to removably couple with the first quick-connect coupler. The first quick-connect coupler and second quick-connect coupler cooperate to fluidly couple the open end to the interior portion when the riser attachment device is coupled to the drip riser and the valve is opened.

Disclosed are processes, apparatuses, and systems in natural gas pipelines to significantly reduce pigging and blowdown emissions. In an example, a process involves filtering and/or separating pigging or blowdown emissions. The filtered and/or separated pigging/blowdown products can then be stored in a storage, sent back into the natural gas pipeline at a downstream location, or sent to an adjacent pipeline.

The present invention provides a drain apparatus (200) for use in a subsea pipeline to remove liquid from a multiphase flow in the subsea pipeline. The drain apparatus comprises a first channel (20) for carrying a multiphase flow comprising liquid and gas phases; and liquid extraction means (11, 12, 14, 18) for extracting the liquid phase from the multiphase flow in the first channel (20). The internal diameter of the first channel (20) is substantially the same as an internal diameter of a subsea pipe arranged to carry the multiphase flow in the subsea pipeline, such that a pig travelling along the subsea pipe can pass through the first channel (20). The present invention also provides a subsea pipeline comprising a subsea pipe for transporting a multiphase flow subsea; and at least one drain. The at least one drain is disposed partway along a gradient in the subsea pipe to reduce liquid holdup.

A flowline dewatering system comprising at least one pump and a pig train supported by a gas pressure enabling suction conditions for the pump. A method to dewater a flowline using the system.

Disclosed are processes, apparatuses, and systems in natural gas pipelines to significantly reduce pigging and blowdown emissions. In an example, a process involves filtering and/or separating pigging or blowdown emissions. The filtered and/or separated pigging/blowdown products can then be stored in a storage, sent back into the natural gas pipeline at a downstream location, or sent to an adjacent pipeline.

Disclosed are processes, apparatuses, and systems in natural gas pipelines to significantly reduce pigging and blowdown emissions. In an example, a process involves filtering and/or separating pigging or blowdown emissions. The filtered and/or separated pigging/blowdown products can then be stored in a storage, sent back into the natural gas pipeline at a downstream location, or sent to an adjacent pipeline.

Disclosed are processes, apparatuses, and systems in natural gas pipelines to significantly reduce pigging and blowdown emissions. In an example, a process involves filtering and/or separating pigging or blowdown emissions. The filtered and/or separated pigging/blowdown products can then be stored in a storage, sent back into the natural gas pipeline at a downstream location, or sent to an adjacent pipeline.

The present invention provides a drain apparatus (200) for use in a subsea pipeline to remove liquid from a multiphase flow in the subsea pipeline. The drain apparatus comprises a first channel (20) for carrying a multiphase flow comprising liquid and gas phases; and liquid extraction means (11, 12, 14, 18) for extracting the liquid phase from the multiphase flow in the first channel (20). The internal diameter of the first channel (20) is substantially the same as an internal diameter of a subsea pipe arranged to carry the multiphase flow in the subsea pipeline, such that a pig travelling along the subsea pipe can pass through the first channel (20). The present invention also provides a subsea pipeline comprising a subsea pipe for transporting a multiphase flow subsea; and at least one drain. The at least one drain is disposed partway along a gradient in the subsea pipe to reduce liquid holdup.