Sea Water Intakes
Sea water is frequently required in large quantities for cooling purposes. One of the problems
associated with sea water intakes in marine- or land-based installations is the occurrence of
gross marine fouling of the entry. This may be of soft growth, barnacles or bivalves. Not only
can this restrict the water flow but the marine fouling may be detached from time to time and
cause blockages in heat exchangers or severe mechanical damage to pumps and valves.
Injection of chemicals such as chlorine can be effective against marine fouling organisms.
However, additions must be closely controlled to be effective and even so, may have a
detrimental effect on the installation and the environment near the outflow. Storage of bulk
chlorine can also be hazardous. Adequate control is possible during steady-state running
conditions but this becomes difficult during downtime when flow ceases.
An alternative is to make intakes and intake screens of 90/10 copper-nickel which is resistant to
fouling. The intake pipes themselves may be of copper-nickel or large concrete piping may be
internally lined either by casting the concrete round a formed pipe or by attaching sheet inside
pipes by rivets or adhesive.