| 摘要 |
<p>An apparatus for venting an annular space between a liner and a pipeline of a subsea riser 2 having upper and lower ends for conveying hydrocarbons, said apparatus comprising permeate recovery means for recovering permeate passing through the liner into the annular space. The permeate recovery means comprises a first vent port 10 provided in a wall of the pipeline at a lower region of the pipeline and communicating with a permeate recovery line 11 defining a flow path between the annular space and a permeate collection vessel 12. The permeate collection vessel is provided with a vacuum pump for aiding extraction of liquid permeate from the annular space adjacent the first vent port.</p> |
