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The glycol is recycled by removing the absorbed liquid.
This is done in the reboiler, which is filled with rich glycol and
heated to boil out the liquids at temperature of about 130-180 °C
(260-350°F) for a number of hours. Usually there is a distillation
column on the gas vent to further improve separation of glycol and
other hydrocarbons. For higher capacity there are often two
reboilers which alternate between heating rich glycol and draining
recycled lean glycol.
On a stand-alone unit the heat is supplied from a burner
that uses the recovered vaporized hydrocarbons. In other designs
the heating will use a combination of hot cooling media from other
parts of the process and electric heaters, and recycle the
hydrocarbon liquids to the third stage separator.

Compressor anti surge and performance
Several types of compressors are used for gas compression,
each with different characteristics such as operating power, speed,
pressure and volume:
Compressor that use a piston and cylinder design with 2-2
cylinders are built up to about 30 MW power, around 500-1800
rpm (lower for higher power) with pressure up to 5MPa (500 bars).
Used for lower capacity gas compression and high reservoir
pressure gas injection.
Screw compressors are manufactured up to several MW,
synchronous speed (3000/3600 rpm) and pressure up to about
2.5 MPa (25 bar). Two counter rotating screws with matching
profiles provide positive displacement and a wide operating range.
Typical use is natural gas gathering.
Axial blade and fin type compressors with up to 15 wheels
provide high volumes at relatively low pressure differential
(discharge pressure 3-5 times inlet pressure), speeds of 5000-8000
3
rpm, and inlet flows to 200.000 m /hour. Applications include air
compressors and cooling compression

Gas Treatment
When the gas is exported, many gas trains include
additional equipment for further gas processing, to remove

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