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Excess heat is disposed e.g. by sea water cooling. However
hot seawater is extremely corrosive, so materials with high
resistance to corrosion, such as titanium must be used.

Scrubbers and reboilers
The separated gas may contain mist and other liquid
droplets. Liquid drops of water and hydrocarbons also form when
the gas is cooled in the heat exchanger, and must be removed
before it reaches the compressor. If liquid droplets enter the
compressor they will erode the fast rotating blades. A scrubber is
designed to remove small fractions of liquid from the gas.

Figure 6.3 – Scheme scrubbers and reboilers

Various gas drying equipment is available, but the most
common suction (compressor) scrubber is based on dehydration by
absorption in Tri Ethylene Glycol (TEG). The scrubber consists of
many levels of glycol layers. A large number of gas traps
(enlarged detail) force the gas to bubble through each glycol layer
as it flows from the bottom up each division to the top.
Lean glycol is pumped in at the top, from the holding tank.
It flows from level to level against the gas flow as it spills over the
edge of each trap. During this process it absorbs liquids from the
gas and comes out as rich glycol at the bottom. The holding tank
also functions as a heat exchanger for liquid from and to the
reboilers.

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