Patent ID: 8342248

Claim:
An apparatus for venting an annular space between a liner and a pipeline of a subsea riser for conveying hydrocarbons, said apparatus comprising: permeate recovery apparatus configured for recovering permeate passing through the liner into said annular space; said permeate recovery apparatus comprises a permeate collection vessel; a first vent port in a wall of the pipeline at or adjacent a lower region of the pipeline, a permeate recovery line communicating with the first vent port and configured for defining a flow path between said annular space and said permeate collection vessel; and a second vent port in a wall of said pipeline at or adjacent an upper region of said pipeline; a second permeate recovery line communicating with said second vent port for venting gaseous permeate from said annular space, said permeate collection vessel being connected to said first vent port for collecting primarily liquid permeate from said first vent port.